diff --git a/LCTT翻译规范.md b/LCTT翻译规范.md deleted file mode 100644 index b9a514f115..0000000000 --- a/LCTT翻译规范.md +++ /dev/null @@ -1,4 +0,0 @@ -# Linux中国翻译规范 -1. 翻译中出现的专有名词，可参见Dict.md中的翻译。 -2. 英文人名，如无中文对应译名，一般不译。 -2. 缩写词，一般不须翻译，可考虑旁注中文全名。 \ No newline at end of file diff --git a/README.md b/README.md index 9d0e3e2d77..6590da83cb 100644 --- a/README.md +++ b/README.md @@ -1,8 +1,8 @@ -![待翻译](https://lctt.github.io/TranslateProject/badge/sources.svg) -![翻译中](https://lctt.github.io/TranslateProject/badge/translating.svg) -![待校正](https://lctt.github.io/TranslateProject/badge/translated.svg) -![已发布](https://lctt.github.io/TranslateProject/badge/published.svg) +[![待翻译](https://lctt.github.io/TranslateProject/badge/sources.svg)](https://lctt.github.io/new) +[![翻译中](https://lctt.github.io/TranslateProject/badge/translating.svg)](https://lctt.github.io/translating) 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+![LCTT](https://lctt.github.io/wiki/images/lctt_logo.png) -LCTT 的组成 -------------------------------- - -**选题**，负责选择合适的内容，并将原文转换为 markdown 格式，提交到 LCTT 的 [TranslateProject](https://github.com/LCTT/TranslateProject) 库中。 - -**译者**，负责从选题中选择内容进行翻译。 - -**校对**，负责将初译的文章进行文字润色、技术校对等工作。 - -**发布**，负责将校对后的文章，排版进行发布。 +- LCTT 官网： [https://linux.cn/lctt/](https://linux.cn/lctt/) +- LCTT 状态： [https://lctt.github.io/](https://lctt.github.io/) 加入我们 ------------------------------- -请首先加入翻译组的 QQ 群，群号是：198889102，加群时请说明是“志愿者”。加入后记得修改您的群名片为您的 GitHub 的 ID。 +请首先加入翻译组的 QQ 群，群号是：**198889102**，加群时请说明是“*志愿者*”。 -加入的成员，请先阅读 [WIKI 如何开始](https://github.com/LCTT/TranslateProject/wiki/01-如何开始)。 +加入的成员，请： + +1. 修改你的 QQ 群名片为“译者-您的_GitHub_ID”。 +2. 阅读 [WIKI](http://lctt.github.io/wiki) 了解如何开始。 +3. 遇到不解之处，请在群内发问。 如何开始 ------------------------------- -请阅读 [WIKI](https://github.com/LCTT/TranslateProject/wiki)。 +请阅读 [WIKI](http://lctt.github.io/wiki)。如需要协助，请在群内发问。 历史 ------------------------------- @@ -79,44 +75,52 @@ LCTT 的组成 * 2018/08/17 提升 pityonline 为核心成员，担任校对，并接受他的建议采用 PR 审核模式。 * 2018/09/10 [LCTT 五周年](https://linux.cn/article-9999-1.html)。 * 2018/10/25 重构了 CI，感谢 vizv、lujun9972、bestony。 +* 2018/11/13 [成立了项目管理委员会（PMC）](https://linux.cn/article-10279-1.html)，初始成员为：@wxy （主席）、@oska874、@lujun9972、@bestony、@pityonline、@geekpi、@qhwdw。 -核心成员 + +项目管理委员及核心成员 ------------------------------- -目前 LCTT 核心成员有： +LCTT 现由项目管理委员会（PMC）进行管理，成员如下： -- 组长 @wxy, -- 选题 @oska874, -- 选题 @lujun9972, -- 技术 @bestony, -- 校对 @jasminepeng, -- 校对 @pityonline, -- 钻石译者 @geekpi, -- 钻石译者 @qhwdw, -- 钻石译者 @GOLinux, -- 核心成员 @GHLandy, -- 核心成员 @martin2011qi, -- 核心成员 @ictlyh, -- 核心成员 @strugglingyouth, -- 核心成员 @FSSlc, -- 核心成员 @zpl1025, -- 核心成员 @runningwater, -- 核心成员 @bazz2, -- 核心成员 @Vic020, -- 核心成员 @alim0x, -- 核心成员 @tinyeyeser, -- 核心成员 @Locez, -- 核心成员 @ucasFL, -- 核心成员 @rusking, -- 核心成员 @MjSeven -- 前任选题 @DeadFire, -- 前任校对 @reinoir222, -- 前任校对 @PurlingNayuki, -- 前任校对 @carolinewuyan, -- 功勋成员 @vito-L, -- 功勋成员 @willqian, -- 功勋成员 @vizv, -- 功勋成员 @dongfengweixiao, +- 🎩 主席 @wxy +- 🎩 选题 @oska874 +- 🎩 选题 @lujun9972 +- 🎩 技术 @bestony +- 🎩 校对 @pityonline +- 🎩 译者 @geekpi +- 🎩 译者 @qhwdw + +目前 LCTT 核心成员有： + +- ❤️ 核心成员 @vizv +- ❤️ 核心成员 @zpl1025 +- ❤️ 核心成员 @runningwater +- ❤️ 核心成员 @FSSlc +- ❤️ 核心成员 @Vic020 +- ❤️ 核心成员 @alim0x +- ❤️ 核心成员 @martin2011qi +- ❤️ 核心成员 @Locez +- ❤️ 核心成员 @ucasFL +- ❤️ 核心成员 @MjSeven + +曾经做出了巨大贡献的核心成员，被列入荣誉榜： + +- 🏆 前任选题 @DeadFire +- 🏆 前任校对 @reinoir222 +- 🏆 前任校对 @PurlingNayuki +- 🏆 前任校对 @carolinewuyan +- 🏆 前任校对 @jasminepeng +- 🏆 功勋成员 @tinyeyeser +- 🏆 功勋成员 @vito-L +- 🏆 功勋成员 @willqian +- 🏆 功勋成员 @GOLinux +- 🏆 功勋成员 @bazz2 +- 🏆 功勋成员 @ictlyh +- 🏆 功勋成员 @dongfengweixiao +- 🏆 功勋成员 @strugglingyouth +- 🏆 功勋成员 @GHLandy +- 🏆 功勋成员 @rusking 全部成员列表请参见： https://linux.cn/lctt-list/ 。 diff --git a/published/20180307 Protecting Code Integrity with PGP - Part 4- Moving Your Master Key to Offline Storage.md b/published/20180307 Protecting Code Integrity with PGP - Part 4- Moving Your Master Key to Offline Storage.md new file mode 100644 index 0000000000..666c661806 --- /dev/null +++ b/published/20180307 Protecting Code Integrity with PGP - Part 4- Moving Your Master Key to Offline Storage.md @@ -0,0 +1,154 @@ +用 PGP 保护代码完整性（四）：将主密钥移到离线存储中 +====== +> 如果开发者的 PGP 密钥被偷了，危害非常大。了解一下如何更安全。 + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/industry-1920.jpg?itok=gI3QraS8) + +在本系列教程中，我们为使用 PGP 提供了一个实用指南。你可以从下面的链接中查看前面的文章： + +- [第一部分：基本概念和工具][1] +- [第二部分：生成你的主密钥][2] +- [第三部分：生成 PGP 子密钥][3] + +这是本系列教程的第四部分，我们继续本教程，我们将谈一谈如何及为什么要将主密钥从你的家目录移到离线存储中。现在开始我们的教程。 + +#### 清单 + + * 准备一个加密的可移除的存储（必要） + * 备份你的 GnuPG 目录（必要） + * 从你的家目录中删除主密钥（推荐） + * 从你的家目录中删除吊销证书（推荐） + +#### 考虑事项 + +为什么要从你的家目录中删除你的主 [C] 密钥 ？这样做的主要原因是防止你的主密钥失窃或意外泄露。对于心怀不轨的人来说，私钥对他们具有很大的诱惑力 —— 我们知道有几个恶意软件成功地实现了扫描用户的家目录并将发现的私钥内容上传。 + +对于开发者来说，私钥失窃是非常危险的事情 —— 在自由软件的世界中，这无疑是身份证明失窃。从你的家目录中删除私钥将帮你防范这类事件的发生。 + +#### 备份你的 GnuPG 目录 + +**!!!绝对不要跳过这一步!!!** + +备份你的 PGP 密钥将让你在需要的时候很容易地恢复它们，这很重要！（这与我们做的使用 paperkey 的灾难级备份是不一样的）。 + +#### 准备可移除的加密存储 + +我们从取得一个（最好是两个）小型的 USB “拇指“ 驱动器（可加密 U 盘）开始，我们将用它来做备份。你首先需要去加密它们： + +加密密码可以使用与主密钥相同的密码。 + +#### 备份你的 GnuPG 目录 + +加密过程结束之后，重新插入 USB 驱动器并确保它能够正常挂载。你可以通过运行 `mount` 命令去找到设备挂载点的完全路径。（在 Linux 下，外置介质一般挂载在 `/media/disk` 下，Mac 一般在它的 `/Volumes` 下） + +你知道了挂载点的全路径后，将你的整个 GnuPG 的目录复制进去： + +``` +$ cp -rp ~/.gnupg [/media/disk/name]/gnupg-backup +``` + +（注意：如果出现任何套接字不支持的错误，没有关系，直接忽略它们。） + +现在，用如下的命令去测试一下，确保它们能够正常地工作： + +``` +$ gpg --homedir=[/media/disk/name]/gnupg-backup --list-key [fpr] +``` + +如果没有出现任何错误，说明一切正常。弹出这个 USB 驱动器并给它粘上一个明确的标签，以便于你下次需要它时能够很快找到它。接着，将它放到一个安全的 —— 但不要太远 —— 的地方，因为从现在起，你需要偶尔使用它来做一些像编辑身份信息、添加或吊销子证书、或签署其它人的密钥这样的事情。 + +#### 删除主密钥 + +我们家目录中的文件并没有像我们所想像的那样受到保护。它们可能会通过许多不同的方式被泄露或失窃： + + * 通过快速复制来配置一个新工作站时的偶尔事故 + * 通过系统管理员的疏忽或恶意操作 + * 通过安全性欠佳的备份 + * 通过桌面应用中的恶意软件（浏览器、pdf 查看器等等） + * 通过跨境胁迫 + +使用一个很好的密码来保护你的密钥是降低上述风险的一个很好方法，但是密码能够通过键盘记录器、背后窥视、或其它方式被发现。基于以上原因，我们建议去配置一个从你的家目录上可移除的主密钥，将它保存在一个离线存储中。 + +##### 删除你的主密钥 + +**请查看前面的节，确保你有完整的你的 GnuPG 目录的一个备份。如果你没有一个可用的备份，下面所做的操作将会使你的主密钥失效！！！** + +首先，识别你的主密钥的 keygrip： + +``` +$ gpg --with-keygrip --list-key [fpr] +``` + +它的输出应该像下面这样： + +``` +pub rsa4096 2017-12-06 [C] [expires: 2019-12-06] + 111122223333444455556666AAAABBBBCCCCDDDD + Keygrip = AAAA999988887777666655554444333322221111 +uid [ultimate] Alice Engineer +uid [ultimate] Alice Engineer +sub rsa2048 2017-12-06 [E] + Keygrip = BBBB999988887777666655554444333322221111 +sub rsa2048 2017-12-06 [S] + Keygrip = CCCC999988887777666655554444333322221111 +``` + +找到 `pub` 行下方的 `Keygrip` 条目（就在主密钥指纹的下方）。它与你的家目录下 `.gnupg` 目录下的一个文件是一致的： + +``` +$ cd ~/.gnupg/private-keys-v1.d +$ ls +AAAA999988887777666655554444333322221111.key +BBBB999988887777666655554444333322221111.key +CCCC999988887777666655554444333322221111.key +``` + +现在你做的全部操作就是简单地删除与主密钥 keygrip 一致的 `.key` 文件： + +``` +$ cd ~/.gnupg/private-keys-v1.d +$ rm AAAA999988887777666655554444333322221111.key +``` + +现在，如果运行 `--list-secret-keys` 命令将出现问题，它将显示主密钥丢失（`#` 表示不可用）： + +``` +$ gpg --list-secret-keys +sec# rsa4096 2017-12-06 [C] [expires: 2019-12-06] + 111122223333444455556666AAAABBBBCCCCDDDD +uid [ultimate] Alice Engineer +uid [ultimate] Alice Engineer +ssb rsa2048 2017-12-06 [E] +ssb rsa2048 2017-12-06 [S] +``` + +#### 删除吊销证书 + +你应该去删除的另一个文件是吊销证书（**删除之前，确保你的备份中有它**），它是使用你的主密钥自动创建的。吊销证书允许一些人去永久标记你的证书为吊销状态，这意味着它无论在任何用途中将不再被使用或信任。一般是使用它来吊销由于某些原因不再受控的一个密钥 —— 比如，你丢失了密钥密码。 + +与使用主密钥一样，如果一个吊销证书泄露到恶意者手中，他们能够使用它去破坏你的开发者数字身份，因此，最好是从你的家目录中删除它。 + +``` +cd ~/.gnupg/openpgp-revocs.d +rm [fpr].rev +``` + +在下一篇文章中，你将学习如何保护你的子密钥。敬请期待。 + +从来自 Linux 基金会和 edX 的免费课程 [“Linux 入门”][4] 中学习更多 Linux 知识。 + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage + +作者：[Konstantin Ryabitsev][a] +译者：[qhwdw](https://github.com/qhwdw) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.linux.com/users/mricon +[1]:https://linux.cn/article-9524-1.html +[2]:https://linux.cn/article-9529-1.html +[3]:https://linux.cn/article-9607-1.html +[4]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/published/20140114 Caffeinated 6.828：Lab 2 Memory Management.md b/published/201811/20140114 Caffeinated 6.828：Lab 2 Memory Management.md similarity index 100% rename from published/20140114 Caffeinated 6.828：Lab 2 Memory Management.md rename to published/201811/20140114 Caffeinated 6.828：Lab 2 Memory Management.md diff --git a/published/20160627 9 Best Free Video Editing Software for Linux In 2017.md b/published/201811/20160627 9 Best Free Video Editing Software for Linux In 2017.md similarity index 100% rename from published/20160627 9 Best Free Video Editing Software for Linux In 2017.md rename to published/201811/20160627 9 Best Free Video Editing Software for Linux In 2017.md diff --git a/published/20170928 A 3-step process for making more transparent decisions.md b/published/201811/20170928 A 3-step process for making more transparent decisions.md similarity index 100% rename from published/20170928 A 3-step process for making more transparent decisions.md rename to published/201811/20170928 A 3-step process for making more transparent decisions.md diff --git a/published/20171002 Three Alternatives for Enabling Two Factor Authentication For SSH On Ubuntu 16.04 And Debian Jessie.md b/published/201811/20171002 Three Alternatives for Enabling Two Factor Authentication For SSH On Ubuntu 16.04 And Debian Jessie.md similarity index 100% rename from published/20171002 Three Alternatives for Enabling Two Factor Authentication For SSH On Ubuntu 16.04 And Debian Jessie.md rename to published/201811/20171002 Three Alternatives for Enabling Two Factor Authentication For SSH On Ubuntu 16.04 And Debian Jessie.md diff --git a/published/20171027 Scout out code problems with SonarQube.md b/published/201811/20171027 Scout out code problems with SonarQube.md similarity index 100% rename from published/20171027 Scout out code problems with SonarQube.md rename to published/201811/20171027 Scout out code problems with SonarQube.md diff --git a/published/20171116 How to use a here documents to write data to a file in bash script.md b/published/201811/20171116 How to use a here documents to write data to a file in bash script.md similarity index 100% rename from published/20171116 How to use a here documents to write data to a file in bash script.md rename to published/201811/20171116 How to use a here documents to write data to a file in bash script.md diff --git a/published/20171202 Simulating the Altair.md b/published/201811/20171202 Simulating the Altair.md similarity index 100% rename from published/20171202 Simulating the Altair.md rename to published/201811/20171202 Simulating the Altair.md diff --git a/published/20171229 Excellent Free Roguelike Games.md b/published/201811/20171229 Excellent Free Roguelike Games.md similarity index 100% rename from published/20171229 Excellent Free Roguelike Games.md rename to published/201811/20171229 Excellent Free Roguelike Games.md diff --git a/published/20180101 Manage Your Games Using Lutris In Linux.md b/published/201811/20180101 Manage Your Games Using Lutris In Linux.md similarity index 100% rename from published/20180101 Manage Your Games Using Lutris In Linux.md rename to published/201811/20180101 Manage Your Games Using Lutris In Linux.md diff --git a/published/20180110 Using Your Own Private Registry with Docker Enterprise Edition.md b/published/201811/20180110 Using Your Own Private Registry with Docker Enterprise Edition.md similarity index 100% rename from published/20180110 Using Your Own Private Registry with Docker Enterprise Edition.md rename to published/201811/20180110 Using Your Own Private Registry with Docker Enterprise Edition.md diff --git a/published/20180127 Write Dumb Code.md b/published/201811/20180127 Write Dumb Code.md similarity index 100% rename from published/20180127 Write Dumb Code.md rename to published/201811/20180127 Write Dumb Code.md diff --git a/published/20180215 Build a bikesharing app with Redis and Python.md b/published/201811/20180215 Build a bikesharing app with Redis and Python.md similarity index 100% rename from published/20180215 Build a bikesharing app with Redis and Python.md rename to published/201811/20180215 Build a bikesharing app with Redis and Python.md diff --git a/published/201811/20180227 Emacs -1- Ditching a bunch of stuff and moving to Emacs and org-mode.md b/published/201811/20180227 Emacs -1- Ditching a bunch of stuff and moving to Emacs and org-mode.md new file mode 100644 index 0000000000..9f2b5512ca --- /dev/null +++ b/published/201811/20180227 Emacs -1- Ditching a bunch of stuff and moving to Emacs and org-mode.md @@ -0,0 +1,78 @@ +Emacs 系列（一）：抛掉一切，投入 Emacs 和 Org 模式的怀抱 +====== + +我必须承认，在使用了几十年的 vim 后， 我被 [Emacs][1] 吸引了。 + +长期以来，我一直对如何组织安排事情感到沮丧。我也有用过 [GTD][2] 和 [ZTD][3] 之类的方法，但是像邮件或是大型文件这样的事务真的很难来组织安排。 + +我一直在用 Asana 处理任务，用 Evernote 做笔记，用 Thunderbird 处理邮件，把 ikiwiki 和其他的一些项目组合作为个人知识库，而且还在电脑的归档了各种文件。当我的新工作需要将 Slack 也加入进来时，我终于忍无可忍了。 + +许多 TODO 管理工具与电子邮件集成的很差。当你想做“提醒我在一周内回复这个邮件”之类的事时，很多时候是不可能的，因为这个工具不能以一种能够轻松回复的方式存储邮件。而这个问题在 Slack 上更为严重。 + +就在那时，我偶然发现了 [Carsten Dominik 在 Google Talk 上关于 Org 模式的讲话][4]。Carsten 是 Org 模式的作者，即便是这个讲话已经有 10 年了，但它仍然很具有参考价值。 + +我之前有用过 [Org 模式][5]，但是每次我都没有真正的深入研究它， +因为我当时的反应是“一个大纲编辑器？但我需要的是待办事项列表”。我就这么错过了它。但实际上 Org 模式就是我所需要的。 + +### 什么是 Emacs？什么是 Org 模式？ + +Emacs 最初是一个文本编辑器，现在依然是一个文本编辑器，而且这种传统无疑贯穿始终。但是说 Emacs 是个编辑器是很不公平的。 + +Emacs 更像一个平台或是工具包。你不仅可以用它来编辑源代码，而且配置 Emacs 本身也是编程，里面有很多模式。就像编写一个 Firefox 插件一样简单，只要几行代码，然后，模式里的操作就改变了。 + +Org 模式也一样。确实，它是一个大纲编辑器，但它真正所包含的不止如此。它是一个信息组织平台。它的网站上写着，“你可以用纯文本来记录你的生活：你可以用 Org 模式来记笔记，处理待办事项，规划项目和使用快速有效的纯文本系统编写文档。” + +### 捕获 + +如果你读过基于 GTD 的生产力指南，那么他们强调的一件事就是毫不费力地获取项目。这个想法是，当某件事突然出现在你的脑海里时，把它迅速输入一个受信任的系统，这样你就可以继续做你正在做的事情。Org 模式有一个专门的捕获系统。我可以在 Emacs 的任何地方按下 `C-c c` 键，它就会空出一个位置来记录我的笔记。最关键的是，自动嵌入到笔记中的链接可以链接到我按下 `C-c c` 键时正在编辑的那一行。如果我正在编辑文件，它会链回到那个文件和我所在的行。如果我正在浏览邮件，它就会链回到那封邮件（通过邮件的 Message-Id，这样它就可以在任何一个文件夹中找到邮件）。聊天时也一样，甚至是当你在另一个 Org 模式中也可也这样。 + +这样我就可以做一个笔记，它会提醒我在一周内回复某封邮件，当我点击这个笔记中的链接时，它会在我的邮件阅读器中弹出这封邮件 —— 即使我随后将它从收件箱中存档。 + +没错，这正是我要找的！ + +### 工具套件 + +一旦你开始使用 Org 模式，很快你就会想将所有的事情都集成到里面。有可以从网络上捕获内容的浏览器插件，也有多个 Emacs 邮件或新闻阅读器与之集成，ERC（IRC 客户端）也不错。所以我将自己从 Thunderbird 和 mairix + mutt （用于邮件归档）换到了 mu4e，从 xchat + slack 换到了 ERC。 + +你可能不明白，我喜欢这些基于 Emacs 的工具，而不是具有相同功能的单独的工具。 + +一个小花絮：我又在使用离线 IMAP 了！我甚至在很久以前就用过 GNUS。 + +### 用一个 Emacs 进程来管理 + +我以前也经常使用 Emacs，那时，Emacs 是一个“大”的程序（现在显示电源状态的小程序占用的内存要比 Emacs 多）。当时存在在启动时间过长的问题，但是现在已经有连接到一个正在运行的 Emacs 进程的解决方法。 + +我喜欢用 Mod-p（一个 [xmonad][6] 中 [dzen][7] 菜单栏的快捷方式，但是在大多数传统的桌面环境中该功能的快捷键是 `Alt-F2`）来启动程序（LCTT 译注：xmonad 是一种平铺桌面；dzen 是 X11 窗口下管理消息、提醒和菜单的程序）。这个设置在不运行多个[emacs 们](https://www.emacswiki.org/emacs/Emacsen)emacsen时很方便，因为这样就不会在试图捕获另一个打开的文件时出问题。这中方法很简单：创建一个叫 `em` 的脚本并将它放到我自己的环境变量中。就像这样： + +``` +#!/bin/bash exec emacsclient -c -a "" "$@" +``` + +如果没有 emacs 进程存在的话，就会创建一个新的 emacs 进程，否则的话就直接使用已存在的进程。这样做还有一个好处：`-nw` 之类的参数工作的很好，它实际上就像在 shell 提示符下输入 `emacs` 一样。它很适合用于设置 `EDITOR` 环境变量。 + +### 下一篇 + +接下来我将讨论我的使用情况，并展示以下的配置： + + * Org 模式，包括计算机之间的同步、捕获、日程和待办事项、文件、链接、关键字和标记、各种导出（幻灯片）等。 + * mu4e，用于电子邮件，包括多个账户，bbdb 集成 + * ERC，用于 IRC 和即时通讯 + +-------------------------------------------------------------------------------- + +via: http://changelog.complete.org/archives/9861-emacs-1-ditching-a-bunch-of-stuff-and-moving-to-emacs-and-org-mode + +作者：[John Goerzen][a] +译者：[oneforalone](https://github.com/oneforalone) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:http://changelog.complete.org/archives/author/jgoerzen +[1]:https://www.gnu.org/software/emacs/ +[2]:https://gettingthingsdone.com/ +[3]:https://zenhabits.net/zen-to-done-the-simple-productivity-e-book/ +[4]:https://www.youtube.com/watch?v=oJTwQvgfgMM +[5]:https://orgmode.org/ +[6]:https://wiki.archlinux.org/index.php/Xmonad_(%E7%AE%80%E4%BD%93%E4%B8%AD%E6%96%87) +[7]:http://robm.github.io/dzen/ diff --git a/published/20180305 Getting started with Python for data science.md b/published/201811/20180305 Getting started with Python for data science.md similarity index 100% rename from published/20180305 Getting started with Python for data science.md rename to published/201811/20180305 Getting started with Python for data science.md diff --git a/translated/talk/20180308 20 questions DevOps job candidates should be prepared to answer.md b/published/201811/20180308 20 questions DevOps job candidates should be prepared to answer.md similarity index 51% rename from translated/talk/20180308 20 questions DevOps job candidates should be prepared to answer.md rename to published/201811/20180308 20 questions DevOps job candidates should be prepared to answer.md index c236b5fef4..b675b5764b 100644 --- a/translated/talk/20180308 20 questions DevOps job candidates should be prepared to answer.md +++ b/published/201811/20180308 20 questions DevOps job candidates should be prepared to answer.md @@ -1,26 +1,34 @@ -DevOps应聘者应该准备回答的20个问题 +DevOps 应聘者应该准备回答的 20 个问题 ====== +> 想要建立一个积极，富有成效的工作环境？ 在招聘过程中要专注于寻找契合点。 + ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/hire-job-career.png?itok=SrZo0QJ3) -聘请一个不合适的人代价是很高的。根据Link人力资源的首席执行官Jörgen Sundberg的统计，招聘，雇佣一名新员工将会花费公司$240,000之多，当你进行了一次不合适的招聘： - * 你失去了他们所知道的。 - * 你失去了他们认识的人 + +聘请一个不合适的人[代价是很高的][1]。根据 Link 人力资源的首席执行官 Jörgen Sundberg 的统计，招聘、雇佣一名新员工将会花费公司$240,000 之多，当你进行了一次不合适的招聘： + + * 你失去了他们的知识技能。 + * 你失去了他们的人脉。 * 你的团队将可能进入到一个组织发展的震荡阶段 * 你的公司将会面临组织破裂的风险 -当你失去一名员工的时候，你就像丢失了公司图谱中的一块。同样值得一提的是另一端的疼痛。应聘到一个错误工作岗位的员工会感受到很大的压力以及整个身心的不满意，甚至是健康问题。 +当你失去一名员工的时候，你就像丢失了公司版图中的一块。同样值得一提的是另一端的痛苦。应聘到一个错误工作岗位的员工会感受到很大的压力以及整个身心的不满意，甚至是健康问题。 + 另外一方面，当你招聘到合适的人时，新的员工将会： - * 丰富公司现有的文化，使你的组织成为一个更好的工作场所。研究表明一个积极的工作文化能够帮助驱动一个更长久的财务业绩，而且如果你在一个欢快的环境中工 作，你更有可能在生活中做的更好。 + + * 丰富公司现有的文化，使你的组织成为一个更好的工作场所。研究表明一个积极的工作文化能够帮助更长久推动财务业绩增长，而且如果你在一个欢快的环境中工作，你更有可能在生活中做的更好。 * 热爱和你的组织在一起工作。当人们热爱他们所在做的，他们会趋向于做的更好。 -招聘适合的或者加强现有的文化在DevOps和敏捷团多中是必不可少的。也就是说雇佣到一个能够鼓励积极合作的人，以便来自不同背景，有着不同目标和工作方式的团队能够在一起有效的工作。你新雇佣的员工因应该能够帮助团队合作来充分发挥放大他们的价值同时也能够增加员工的满意度以及平衡组织目标的冲突。他或者她应该能够通过明智的选择工具和工作流来促进你的组织，文化就是一切。 +招聘以适合或加强现有的文化在 DevOps 和敏捷团多中是必不可少的。也就是说雇佣到一个能够鼓励积极合作的人，以便来自不同背景，有着不同目标和工作方式的团队能够在一起有效的工作。你新雇佣的员工应该能够帮助团队合作来充分发挥放大他们的价值，同时也能够增加员工的满意度以及平衡组织目标的冲突。他或者她应该能够通过明智的选择工具和工作流来促进你的组织，文化就是一切。 + +作为我们 2017 年 11 月发布的一篇文章 [DevOps 的招聘经理应该准备回答的 20 个问题][4] 的回应，这篇文章将会重点关注在如何招聘最适合的人。 -作为我们2017年11月发布的一篇文章，[DevOps的招聘经理应该准备回答的20个问题][4],这篇文章将会重点关注在如何招聘最适合的人。 ### 为什么招聘走错了方向 -很多公司现在在用的典型的雇佣策略是基于人才过剩的基础上： - * 职位公告栏。 - * 关注和所需才能符合的应聘者。 +很多公司现在用的典型的雇佣策略是基于人才过剩的基础上： + + * 在职位公告栏发布招聘。 + * 关注具有所需才能的应聘者。 * 尽可能找多的候选者。 * 通过面试淘汰弱者。 * 通过正式的面试淘汰更多的弱者。 @@ -30,37 +38,48 @@ DevOps应聘者应该准备回答的20个问题 ![](https://opensource.com/sites/default/files/styles/panopoly_image_original/public/images/life-uploads/hiring_graphic.png?itok=1udGbkhB) 职位公告栏是有成千上万失业者人才过剩的经济大萧条时期发明的。在今天的求职市场上已经没有人才过剩了，然而我们仍然在使用基于此的招聘策略。 + ![](https://opensource.com/sites/default/files/styles/panopoly_image_original/public/images/life-uploads/732px-unemployed_men_queued_outside_a_depression_soup_kitchen_opened_in_chicago_by_al_capone_02-1931_-_nara_-_541927.jpg?itok=HSs4NjCN) ### 雇佣最合适的人员：运用文化和情感 -在人才过剩雇佣策略背后的思想是去设计工作岗位然后将人员安排进去。 -相反，做相反的事情：寻找将会积极融入你的商业文化的人才，然后为他们寻找他们热爱的最合适的岗位。要想如此实现，你必须能够围绕他们热情为他们创造工作岗位。 -**谁正在寻找一份工作？** 根据一份2016年对美国50，000名开发者的调查显示，[85.7%的受访对象][5]要么对新的机会不感兴趣，要么对于寻找新工作没有积极性。在寻找工作的那部分中，有将近[28.3%的求职者][5]来自于朋友的推荐。如果你只是在那些在找工作的人中寻找人才，你将会错过高端的人才。 -**运用团队力量去发现和寻找潜力的雇员**。列如，戴安娜是你的团队中的一名开发者，她所提供的机会即使她已经从事编程很多年而且在期间已经结识了很多从事热爱他们所从事的工作的人。难道你不认为她所推荐的潜在员工在技能，知识和智慧上要比HR所寻找的要优秀吗？在要求戴安娜分享她同伴之前，通知她即将到来的使命任务，向她阐明你要雇佣潜在有探索精神的团队，描述在将来会需要的知识领域。 -**雇员想要什么？**一份来自千禧年，婴儿潮实时期出生的人的对比综合性研究显示，20% 的人所想要的是相同的： + +在人才过剩雇佣策略背后的思想是设计工作岗位然后将人员安排进去。 + +反而应该反过来：寻找将会积极融入你的商业文化的人才，然后为他们寻找他们热爱的最合适的岗位。要想实现这样的目标，你必须能够围绕他们热情为他们创造工作岗位。 + +**谁正在寻找一份工作？** 根据一份 2016 年对美国 50000 名开发者的调查显示，[85.7% 的受访对象][5]要么对新的机会不感兴趣，要么对于寻找新工作没有积极性。在寻找工作的那部分中，有将近 [28.3% 的求职者][5]来自于朋友的推荐。如果你只是在那些在找工作的人中寻找人才，你将会错过高端的人才。 + +**运用团队力量去发现和寻找潜力的雇员**。例如，戴安娜是你的团队中的一名开发者，她所能提供的机会是，她已经[从事编程很多年][6]而且在期间已经结识了很多从事热爱他们所从事的工作的人。难道你不认为她所推荐的潜在员工在技能、知识和智慧上要比 HR 所寻找的要优秀吗？在要求戴安娜分享她同伴之前，通知她即将到来的使命任务，向她阐明你要雇佣潜在有探索精神的团队，描述在将来会需要的知识领域。 + +**雇员想要什么？**一份来自千禧年婴儿潮时期出生的人的对比综合性研究显示，20% 的人所想要的是相同的： + 1. 对组织产生积极的影响 2. 帮助解决社交或者环境上的挑战 3. 和一群有动力的人一起工作 ### 面试的挑战 -面试应该是招聘者和应聘者双方为了寻找最合适的人才进行的一次双方之间的对话。将面试聚焦在企业文化和情感对话两个问题上：这个应聘者将会丰富你的企业文化并且会热爱和你在一起工作吗？你能够在工作中帮他们取得成功吗？ -**对于招聘经理来说：** 每一次的面试都是你学习如何将自己的组织变得对未来的团队成员更有吸引力，并且每次积极的面试多都可能是你发现人才（即使你不会雇佣）的机会。每个人都将会记得积极有效的面试的经历。即使他们不会被雇佣，他们将会和他们的朋友谈论这次经历，你竟会得到一个被推荐的机会。这又很大的好处：如果你无法吸引到这个人才，你也将会从中学习吸取经验并且改善。 -**对面试者来说**：每次的面试都是你释放激情的机会 -### 助你释放潜在雇员激情的20个问题 +面试应该是招聘者和应聘者双方为了寻找最合适的人才进行的一次双方之间的对话。将面试聚焦在企业文化和情感对话两个问题上：这个应聘者将会丰富你的企业文化并且会热爱和你在一起工作吗？你能够在工作中帮他们取得成功吗？ + +**对于招聘经理来说：** 每一次的面试都是你学习如何将自己的组织变得对未来的团队成员更有吸引力，并且每次积极的面试都可能是你发现人才（即使你不会雇佣）的机会。每个人都将会记得积极有效的面试的经历。即使他们不会被雇佣，他们将会和他们的朋友谈论这次经历，你会得到一个被推荐的机会。这有很大的好处：如果你无法吸引到这个人才，你也将会从中学习吸取经验并且改善。 + +**对面试者来说**：每次的面试都是你释放激情的机会。 + +### 助你释放潜在雇员激情的 20 个问题 + 1. 你热爱什么？ - 2. “今天早晨我已经迫不及待的要去工作”你怎么看待这句话？ + 2. “今天早晨我已经迫不及待的要去工作”，你怎么看待这句话？ 3. 你曾经最快乐的是什么？ 4. 你曾经解决问题的最典型的例子是什么，你是如何解决的？ 5. 你如何看待配对学习？ 6. 你到达办公室和离开办公室心里最先想到的是什么？ - 7. 你如果你有一次改变你之前或者现在的共工作的一件事的机会，将会是什么事？ - 8. 当你在这工作的时候，你最兴奋去学习什么？ + 7. 你如果你有一次改变你之前或者现在的工作中的一件事的机会，将会是什么事？ + 8. 当你在工作的时候，你最乐于去学习什么？ 9. 你的梦想是什么，你如何去实现？ 10. 你在学会如何去实现你的追求的时候想要或者需要什么？ 11. 你的价值观是什么？ 12. 你是如何坚守自己的价值观的？ - 13. 平衡在你的生活中意味着什么？ + 13. 在你的生活中平衡意味着什么？ 14. 你最引以为傲的工作交流能力是什么？为什么？ 15. 你最喜欢营造什么样的环境？ 16. 你喜欢别人怎样对待你？ @@ -70,14 +89,13 @@ DevOps应聘者应该准备回答的20个问题 20. 如果你正在雇佣我，你将会问我什么问题？ - -------------------------------------------------------------------------------- via: https://opensource.com/article/18/3/questions-devops-employees-should-answer 作者：[Catherine Louis][a] 译者：[FelixYFZ](https://github.com/FelixYFZ) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20180403 17 Ways To Check Size Of Physical Memory (RAM) In Linux.md b/published/201811/20180403 17 Ways To Check Size Of Physical Memory (RAM) In Linux.md similarity index 100% rename from published/20180403 17 Ways To Check Size Of Physical Memory (RAM) In Linux.md rename to published/201811/20180403 17 Ways To Check Size Of Physical Memory (RAM) In Linux.md diff --git a/published/201811/20180409 5 steps to building a cloud that meets your users- needs.md b/published/201811/20180409 5 steps to building a cloud that meets your users- needs.md new file mode 100644 index 0000000000..b3f44aea92 --- /dev/null +++ b/published/201811/20180409 5 steps to building a cloud that meets your users- needs.md @@ -0,0 +1,101 @@ +构建满足用户需求的云环境的五个步骤 +====== +> 在投入时间和资金开发你的云环境之前，确认什么是你的用户所需要的。 + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/rh_003601_05_mech_osyearbook2016_cloud_cc.png?itok=XSV7yR9e) + +无论你如何定义，云就是你的用户展现其在组织中的价值的另一个工具。当谈论新的范例或者技术（云是两者兼有）的时候很容易被它的新特性所分心。由一系列无止境的问题引发的对话能够很快的被发展为功能愿景清单，所有下面的这些都是你可能已经考虑到的： + + * 是公有云、私有云还是混合云？ + * 会使用虚拟机还是容器，或者是两者？ + * 会提供自助服务吗？ + * 从开发到生产是完全自动的，还是它将需要手动操作？ + * 我们能以多块的速度做到？ + * 关于某某工具？ + +这样的清单还可以列举很多。 + +当开始 IT 现代化，或者数字转型，无论你是如何称呼的，通常方法是开始回答更高管理层的一些高层次问题，这种方法的结果是可以预想到的：失败。经过大范围的调研并且花费了数月的时间（如果不是几年的话）部署了这个最炫的新技术，而这个新的云技术却从未被使用过，而且陷入了荒废，直到它最终被丢弃或者遗忘在数据中心的一角和预算之中。 + +这是因为无论你交付的是什么工具，都不是用户所想要或者需要的。更加糟糕的是，它可能是一个单一的工具，而用户真正需要的是一系列工具 —— 能够随着时间推移，更换升级为更新的、更漂亮的工具，以更好地满足其需求。 + +### 专注于重要的事情 + +问题在于关注，传统上一直是关注于工具。但工具并不是要增加到组织价值中的东西；终端用户利用它做什么才是目的。你需要将你的注意力从创建云（例如技术和工具）转移到你的人员和用户身上。 + +事实上，除了使用工具的用户（而不是工具本身）是驱动价值的因素之外，聚焦注意力在用户身上也是有其它原因的。工具是给用户使用去解决他们的问题并允许他们创造价值的，所以这就导致了如果那些工具不能满足那些用户的需求，那么那些工具将不会被使用。如果你交付给你的用户的工具并不是他们喜欢的，他们将不会使用，这就是人类的人性行为。 + +数十年来，IT 产业只为用户提供一种解决方案，因为仅有一个或两个选择，用户是没有权力去改变的。现在情况已经不同了。我们现在生活在一个技术选择的世界中。不给用户一个选择的机会的情况将不会被接受的；他们在个人的科技生活中有选择，同时希望在工作中也有选择。现在的用户都是受过教育的并且知道将会有比你所提供的更好选择。 + +因此，在物理上的最安全的地点之外，没有能够阻止他们只做他们自己想要的东西的方法，我们称之为“影子 IT”。如果你的组织有如此严格的安全策略和承诺策略而不允许影子 IT，许多员工将会感到灰心丧气并且会离职去其他能提供更好机会的公司。 + +基于以上所有的原因，你必须牢记要首先和你的最终用户设计你的昂贵又费时的云项目。 + +### 创建满足用户需求的云五个步骤的过程 + +既然我们已经知道了为什么，接下来我们来讨论一下怎么做。你如何去为终端用户创建一个云？你怎样重新将你的注意力从技术转移到使用技术的用户身上？ + +根据以往的经验，我们知道最好的方法中包含两件重要的事情：从你的用户中得到及时的反馈，在创建中和用户进行更多的互动。 + +你的云环境将继续随着你的组织不断发展。下面的五个步骤将会帮助你创建满足用户需求的云环境。 + +#### 1、识别谁将是你的用户 + +在你开始询问用户问题之前，你首先必须识别谁将是你的新的云环境的用户。他们可能包括将在云上创建开发应用的开发者；也可能是运营、维护或者或者创建该云的运维团队；还可能是保护你的组织的安全团队。在第一次迭代时，将你的用户数量缩小至人数较少的小组防止你被大量的反馈所淹没，让你识别的每个小组指派两个代表（一个主要的一个辅助的）。这将使你的第一次交付在规模和时间上都很小。 + +#### 2、和你的用户面对面的交谈来收获有价值的输入。 + +获得反馈的最佳途径是和用户直接交谈。群发的邮件会自行挑选出受访者——如果你能收到回复的话。小组讨论会很有帮助的，但是当人们有个私密的、专注的对话者时，他们会比较的坦诚。 + +和你的第一批用户安排个面对面的个人的会谈，并且向他们询问以下的问题： + + * 为了完成你的任务，你需要什么？ + * 为了完成你的任务，你想要什么？ + * 你现在最头疼的技术痛点是什么？ + * 你现在最头疼的政策或者流程痛点是哪个？ + * 关于解决你的需求、希望或痛点，你有什么建议？ + +这些问题只是指导性的，并不一定适合每个组织。你不应该只询问这些问题，他们应该导向更深层次的讨论。确保告诉用户他们任何所说的和被问的都被视作反馈，所有的反馈都是有帮助的，无论是消极的还是积极的。这些对话将会帮助你设置你的开发优先级。 + +收集这种个性化的反馈是保持初始用户群较小的另一个原因：这将会花费你大量的时间来和每个用户交流，但是我们已经发现这是相当值得付出的投入。 + +#### 3、设计并交付你的解决方案的第一个版本 + +一旦你收到初始用户的反馈，就是时候开始去设计并交付一部分的功能了。我们不推荐尝试一次性交付整个解决方案。设计和交付的时期要短；这可以避免你花费一年的时间去构建一个你*认为*正确的解决方案，而只会让你的用户拒绝它，因为对他们来说毫无用处。创建你的云所需要的工具取决于你的组织和它的特殊需求。只需确保你的解决方案是建立在用户的反馈的基础上的，你将功能小块化的交付并且要经常的去征求用户的反馈。 + +#### 4、询问用户对第一个版本的反馈 + +太棒了，现在你已经设计并向你的用户交付了你的炫酷的新的云环境的第一个版本！你并不是花费一整年去完成它而是将它处理成小的模块。为什么将其分为小的模块如此重要呢？因为你要回到你的用户组并且向他们收集关于你的设计和交付的功能。他们喜欢什么？不喜欢什么？你正确的处理了他们所关注的吗？是技术功能上很厉害，但系统进程或者策略方面仍然欠缺吗？ + +再重申一次，你要问的问题取决于你的组织；这里的关键是继续前一个阶段的讨论。毕竟你正在为用户创建云环境，所以确保它对用户来说是有用的并且能够有效利用每个人的时间。 + +#### 5、回到第一步。 + +这是一个迭代的过程。你的首次交付应该是快速而小规模的，而且以后的迭代也应该是这样的。不要期待仅仅按照这个流程完成了一次、两次甚至是三次就能完成。一旦你持续的迭代，你将会吸引更多的用户从而能够在这个过程中得到更好的回报。你将会从用户那里得到更多的支持。你能够迭代的更迅速并且更可靠。到最后，你将会通过改变你的流程来满足用户的需求。 + +用户是这个过程中最重要的一部分，但迭代是第二重要的因为它让你能够回到用户中进行持续沟通从而得到更多有用的信息。在每个阶段，记录哪些是有效的哪些没有起到应有的效果。要自省，要对自己诚实。我们所花费的时间提供了最有价值的了吗？如果不是，在下一个阶段尝试些不同的。在每次循环中不要花费太多时间的最重要的部分是，如果某部分在这次不起作用，你能够很容易的在下一次中调整它，直到你找到能够在你组织中起作用的方法。 + +### 这仅仅是开始 + +通过许多客户约见，从他们那里收集反馈，以及在这个领域的同行的经验，我们一次次的发现在创建云的时候最重要事就是和你的用户交谈。这似乎是很明显的，但很让人惊讶的是很多组织却偏离了这个方向去花费数月或者数年的时间去创建，然后最终发现它对终端用户甚至一点用处都没有。 + +现在你已经知道为什么你需要将你的注意力集中到终端用户身上并且在中心节点和用户一起的互动创建云。剩下的是我们所喜欢的部分，你自己去做的部分。 + +这篇文章是基于一篇作者在 [Red Hat Summit 2018][3] 上发表的文章“[为终端用户设计混合云，要么失败]”。 + + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/4/5-steps-building-your-cloud-correctly + +作者：[Cameron Wyatt][a], [Ian Teksbury][1] +选题：[lujun9972](https://github.com/lujun9972) +译者：[FelixYFZ](https://github.com/FelixYFZ) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/cameronmwyatt +[1]:https://opensource.com/users/itewk +[2]:https://agenda.summit.redhat.com/SessionDetail.aspx?id=154225 +[3]:https://www.redhat.com/en/summit/2018 diff --git a/published/20180409 How to create LaTeX documents with Emacs.md b/published/201811/20180409 How to create LaTeX documents with Emacs.md similarity index 100% rename from published/20180409 How to create LaTeX documents with Emacs.md rename to published/201811/20180409 How to create LaTeX documents with Emacs.md diff --git a/published/201811/20180417 How To Browse Stack Overflow From Terminal.md b/published/201811/20180417 How To Browse Stack Overflow From Terminal.md new file mode 100644 index 0000000000..03d4c9df5f --- /dev/null +++ b/published/201811/20180417 How To Browse Stack Overflow From Terminal.md @@ -0,0 +1,139 @@ +如何在终端中浏览 Stack Overflow +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/04/how2-720x340.png) + +前段时间，我们写了一篇关于 [SoCLI][1] 的文章，它是一个从命令行搜索和浏览 Stack Overflow 网站的 python 脚本。今天，我们将讨论一个名为 “how2” 的类似工具。它是一个命令行程序，可以从终端浏览 Stack Overflow。你可以如你在 [Google 搜索][2]中那样直接用英语查询，然后它会使用 Google 和 Stackoverflow API 来搜索给定的查询。它是使用 NodeJS 编写的自由开源程序。 + +### 使用 how2 从终端浏览 Stack Overflow + +由于 `how2` 是一个 NodeJS 包，我们可以使用 Npm 包管理器安装它。如果你尚未安装 Npm 和 NodeJS，请参考以下指南。 + +在安装 Npm 和 NodeJS 后，运行以下命令安装 how2。 + +``` +$ npm install -g how2 +``` + +现在让我们看下如何使用这个程序浏览 Stack Overflow。使用 `how2` 搜索 Stack Overflow 站点的典型用法是： + +``` +$ how2 +``` + +例如，我将搜索如何创建 tgz 存档。 + +``` +$ how2 create archive tgz +``` + +哎呀！我收到以下错误。 + +``` +/home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/transport.js:59 +Transport.prototype.__proto__ = EventEmitter.prototype; + ^ + + TypeError: Cannot read property 'prototype' of undefined + at Object. (/home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/transport.js:59:46) + at Module._compile (internal/modules/cjs/loader.js:654:30) + at Object.Module._extensions..js (internal/modules/cjs/loader.js:665:10) + at Module.load (internal/modules/cjs/loader.js:566:32) + at tryModuleLoad (internal/modules/cjs/loader.js:506:12) + at Function.Module._load (internal/modules/cjs/loader.js:498:3) + at Module.require (internal/modules/cjs/loader.js:598:17) + at require (internal/modules/cjs/helpers.js:11:18) + at Object. (/home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/stream.js:8:17) + at Module._compile (internal/modules/cjs/loader.js:654:30) + +``` + +我可能遇到了一个 bug。我希望它在未来版本中得到修复。但是，我在[这里][3]找到了一个临时方法。 + + +要临时修复此错误，你需要使用以下命令编辑 `transport.js`： + +``` +$ vi /home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/transport.js +``` + +此文件的实际路径将显示在错误输出中。用你自己的文件路径替换上述文件路径。然后找到以下行： + +``` +var EventEmitter = process.EventEmitter; +``` + +并用以下行替换它： + +``` +var EventEmitter = require('events'); +``` + +按 `ESC` 并输入 `:wq` 以保存并退出文件。 + +现在再次搜索查询。 + +``` +$ how2 create archive tgz +``` + +这是我的 Ubuntu 系统的示例输出。 + +![][5] + +如果你要查找的答案未显示在上面的输出中，请按**空格键**键开始交互式搜索，你可以通过它查看 Stack Overflow 站点中的所有建议问题和答案。 + +![][6] + +使用向上/向下箭头在结果之间移动。得到正确的答案/问题后，点击空格键或回车键在终端中打开它。 + +![][7] + +要返回并退出，请按 `ESC`。 + +**搜索特定语言的答案** + +如果你没有指定语言，它**默认为 Bash** unix 命令行，并立即为你提供最可能的答案。你还可以将结果缩小到特定语言，例如 perl、python、c、Java 等。 + +例如，使用 `-l` 标志仅搜索与 “Python” 语言相关的查询，如下所示。 + +``` +$ how2 -l python linked list +``` + +![][8] + +要获得快速帮助，请输入： + +``` +$ how2 -h +``` + +### 总结 + +`how2` 是一个基本的命令行程序，它可以快速搜索 Stack Overflow 中的问题和答案，而无需离开终端，并且它可以很好地完成这项工作。但是，它只是 Stack overflow 的 CLI 浏览器。对于一些高级功能，例如搜索投票最多的问题，使用多个标签搜索查询，彩色界面，提交新问题和查看问题统计信息等，**SoCLI** 做得更好。 + +就是这些了。希望这篇文章有用。我将很快写一篇新的指南。在此之前，请继续关注！ + +干杯! + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/how-to-browse-stack-overflow-from-terminal/ + +作者：[SK][a] +选题：[lujun9972](https://github.com/lujun9972) +译者：[geekpi](https://github.com/wxy) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.ostechnix.com/author/sk/ +[1]:https://www.ostechnix.com/search-browse-stack-overflow-website-commandline/ +[2]:https://www.ostechnix.com/google-search-navigator-enhance-keyboard-navigation-in-google-search/ +[3]:https://github.com/santinic/how2/issues/79 +[4]:data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[5]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-1.png +[6]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-2.png +[7]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-3.png +[8]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-4.png diff --git a/published/20180417 What developers need to know about security.md b/published/201811/20180417 What developers need to know about security.md similarity index 100% rename from published/20180417 What developers need to know about security.md rename to published/201811/20180417 What developers need to know about security.md diff --git a/published/20180502 9 ways to improve collaboration between developers and designers.md b/published/201811/20180502 9 ways to improve collaboration between developers and designers.md similarity index 100% rename from published/20180502 9 ways to improve collaboration between developers and designers.md rename to published/201811/20180502 9 ways to improve collaboration between developers and designers.md diff --git a/published/20180530 How To Add, Enable And Disable A Repository In Linux.md b/published/201811/20180530 How To Add, Enable And Disable A Repository In Linux.md similarity index 100% rename from published/20180530 How To Add, Enable And Disable A Repository In Linux.md rename to published/201811/20180530 How To Add, Enable And Disable A Repository In Linux.md diff --git a/published/20180615 Complete Sed Command Guide [Explained with Practical Examples].md b/published/201811/20180615 Complete Sed Command Guide [Explained with Practical Examples].md similarity index 100% rename from published/20180615 Complete Sed Command Guide [Explained with Practical Examples].md rename to published/201811/20180615 Complete Sed Command Guide [Explained with Practical Examples].md diff --git a/published/20180618 What-s all the C Plus Fuss- Bjarne Stroustrup warns of dangerous future plans for his C.md b/published/201811/20180618 What-s all the C Plus Fuss- Bjarne Stroustrup warns of dangerous future plans for his C.md similarity index 100% rename from published/20180618 What-s all the C Plus Fuss- Bjarne Stroustrup warns of dangerous future plans for his C.md rename to published/201811/20180618 What-s all the C Plus Fuss- Bjarne Stroustrup warns of dangerous future plans for his C.md diff --git a/published/20180626 8 great pytest plugins.md b/published/201811/20180626 8 great pytest plugins.md similarity index 100% rename from published/20180626 8 great pytest plugins.md rename to published/201811/20180626 8 great pytest plugins.md diff --git a/translated/tech/20180709 Anbox- How To Install Google Play Store And Enable ARM (libhoudini) Support, The Easy Way.md b/published/201811/20180709 Anbox- How To Install Google Play Store And Enable ARM (libhoudini) Support, The Easy Way.md similarity index 68% rename from translated/tech/20180709 Anbox- How To Install Google Play Store And Enable ARM (libhoudini) Support, The Easy Way.md rename to published/201811/20180709 Anbox- How To Install Google Play Store And Enable ARM (libhoudini) Support, The Easy Way.md index 16b2bb8d18..2a8ec9139c 100644 --- a/translated/tech/20180709 Anbox- How To Install Google Play Store And Enable ARM (libhoudini) Support, The Easy Way.md +++ b/published/201811/20180709 Anbox- How To Install Google Play Store And Enable ARM (libhoudini) Support, The Easy Way.md @@ -1,38 +1,38 @@ -Anbox：如何方便地安装 Google Play 商店以及启用 ARM（libhoudini） 支持 +如何在 Anbox 上安装 Google Play 商店及启用 ARM 支持 ====== ![](https://4.bp.blogspot.com/-xBysI_ar5UU/W0NxTe42FkI/AAAAAAAAA2c/KTRtA4C2yYYN9aaMwwAwTXe8deXF4LdNgCLcBGAs/s1600/anbox-google-play-store.png) -**[Anbox][1] 或称为 Anroid in a Box 是一个免费的开源工具，它允许在 Linux 上运行 Android 应用程序**。它的工作原理是在 LXC 容器中运行 Android 运行时环境，重新创建 Android 的目录结构作为可挂载的 loop 镜像，同时使用本机 Linux 内核来执行应用。 +[Anbox][1] （Anroid in a Box）是一个自由开源工具，它允许你在 Linux 上运行 Android 应用程序。它的工作原理是在 LXC 容器中运行 Android 运行时环境，重新创建 Android 的目录结构作为可挂载的 loop 镜像，同时使用本机 Linux 内核来执行应用。 据其网站所述，它的主要特性是安全性、性能、集成和趋同（不同外形尺寸缩放）。 -**使用 Anbox，每个 Android 应用或游戏就像系统应用一样都在一个单独的窗口中启动**，它们的行为或多或少类似于常规窗口，显示在启动器中，可以平铺等等。 +使用 Anbox，每个 Android 应用或游戏就像系统应用一样都在一个单独的窗口中启动，它们的行为或多或少类似于常规窗口，显示在启动器中，可以平铺等等。 -默认情况下，Anbox 没有 Google Play 商店或 ARM 应用支持。要安装应用，你必须下载每个应用 APK 并使用 adb 手动安装。此外，默认情况下不能使用 Anbox 安装 ARM 应用或游戏 - 尝试安装 ARM 应用会显示以下错误： +默认情况下，Anbox 没有 Google Play 商店或 ARM 应用支持。要安装应用，你必须下载每个应用的 APK 并使用 `adb` 手动安装。此外，默认情况下不能使用 Anbox 安装 ARM 应用或游戏 —— 尝试安装 ARM 应用会显示以下错误： ``` Failed to install PACKAGE.NAME.apk: Failure [INSTALL_FAILED_NO_MATCHING_ABIS: Failed to extract native libraries, res=-113] ``` -你可以在 Anbox 中手动设置 Google Play 商店和 ARM 应用支持（通过 libhoudini），但这是一个非常复杂的过程。**为了更容易地在 Anbox 上安装 Google Play 商店和 Google Play 服务，并让它支持 ARM 应用程序和游戏（使用 libhoudini），[geeks-r-us.de][2]（文章是德语）上的人创建了一个自动执行这些任务的脚本**。 +你可以在 Anbox 中手动设置 Google Play 商店和 ARM 应用支持（通过 libhoudini），但这是一个非常复杂的过程。为了更容易地在 Anbox 上安装 Google Play 商店和 Google Play 服务，并让它支持 ARM 应用程序和游戏（使用 libhoudini），[geeks-r-us.de][2]（文章是德语）上的人创建了一个自动执行这些任务的脚本。 在使用之前，我想明确指出，即使在集成 libhoudini 来支持 ARM 后，也并非所有 Android 应用和游戏都能在 Anbox 中运行。某些 Android 应用和游戏可能根本不会出现在 Google Play 商店中，而一些应用和游戏可能可以安装但无法使用。此外，某些应用可能无法使用某些功能。 -### 安装 Google Play 商店并在 Anbox 上启用 ARM 应用/游戏支持（Android in a Box） +### 安装 Google Play 商店并在 Anbox 上启用 ARM 应用/游戏支持 如果你的 Linux 桌面上尚未安装 Anbox，这些说明显然不起作用。如果你还没有，请按照[此处][7]的安装说明安装 Anbox。此外，请确保在安装 Anbox 之后，使用此脚本之前至少运行一次 `anbox.appmgr`，以避免遇到问题。另外，确保在执行下面的脚本时 Anbox 没有运行（我怀疑这是导致评论中提到的这个[问题][8]的原因）。 -1\. 安装所需的依赖项（wget、lzip、unzip 和 squashfs-tools）。 +1、 安装所需的依赖项（wget、lzip、unzip 和 squashfs-tools）。 在 Debian、Ubuntu 或 Linux Mint 中，使用此命令安装所需的依赖项： + ``` sudo apt install wget lzip unzip squashfs-tools - ``` -2\. 下载并运行脚本，在 Anbox 上自动下载并安装 Google Play商店（和 Google Play 服务）和 libhoudini（用于 ARM 应用/游戏支持）。 +2、 下载并运行脚本，在 Anbox 上自动下载并安装 Google Play 商店（和 Google Play 服务）和 libhoudini（用于 ARM 应用/游戏支持）。 **警告：永远不要在不知道它做什么的情况下运行不是你写的脚本。在运行此脚本之前，请查看其[代码][4]。** @@ -42,25 +42,23 @@ sudo apt install wget lzip unzip squashfs-tools wget https://raw.githubusercontent.com/geeks-r-us/anbox-playstore-installer/master/install-playstore.sh chmod +x install-playstore.sh sudo ./install-playstore.sh - ``` -3\. 要让 Google Play 商店在 Anbox 中运行，你需要启用 Google Play 商店和 Google Play 服务的所有权限 +3、要让 Google Play 商店在 Anbox 中运行，你需要启用 Google Play 商店和 Google Play 服务的所有权限 为此，请运行Anbox： ``` anbox.appmgr - ``` -然后进入`设置>应用> Google Play 服务>权限`并启用所有可用权限。对 Google Play 商店也一样！ +然后进入“设置 > 应用 > Google Play 服务 > 权限”并启用所有可用权限。对 Google Play 商店也一样！ ![](https://4.bp.blogspot.com/-_eNBaOz1RFs/W0NySoRZ5qI/AAAAAAAAA2s/tJseV74r-3Y3M6dnUBmMo9mDfQLqNK7YwCLcBGAs/s1600/anbox-google-play-services-permissions.png) 你现在应该可以使用 Google 帐户登录 Google Play 商店了。 -如果未启用 Google Play 商店和 Google Play 服务的所有权限，你可能会在尝试登录 Google 帐户时可能会遇到问题，并显示以下错误消息：“_Couldn't sign in. There was a problem communicating with Google servers. Try again later_ “，如你在下面的截图中看到的那样： +如果未启用 Google Play 商店和 Google Play 服务的所有权限，你可能会在尝试登录 Google 帐户时可能会遇到问题，并显示以下错误消息：“Couldn't sign in. There was a problem communicating with Google servers. Try again later“，如你在下面的截图中看到的那样： ![](https://4.bp.blogspot.com/-00ffP4iLTT4/W0NyBGECDLI/AAAAAAAAA2k/re7YRgzeU6M6ccVnODlYGak0UsdImrJ_ACLcBGAs/s1600/anbox-google-play-error-login-problem-google-servers.png) @@ -68,23 +66,18 @@ anbox.appmgr **如果你在 Anbox 上登录 Google 帐户时遇到一些连接问题**，请确保 `anbox-bride.sh` 正在运行： - * 启动它： - +启动它： ``` sudo /snap/anbox/current/bin/anbox-bridge.sh start - ``` - - * 重启它： - +重启它： ``` sudo /snap/anbox/current/bin/anbox-bridge.sh restart - ``` -根据[此][9]用户的说法，如果 Anbox 仍然存在连接问题，你可能还需要安装 dnsmasq 包。但是在我的 Ubuntu 18.04 桌面上不需要这样做。 +根据[此用户][9]的说法，如果 Anbox 仍然存在连接问题，你可能还需要安装 dnsmasq 包。但是在我的 Ubuntu 18.04 桌面上不需要这样做。 -------------------------------------------------------------------------------- @@ -94,7 +87,7 @@ via: https://www.linuxuprising.com/2018/07/anbox-how-to-install-google-play-stor 作者：[Logix][a] 选题：[lujun9972](https://github.com/lujun9972) 译者：[geekpi](https://github.com/geekpi) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 @@ -107,4 +100,4 @@ via: https://www.linuxuprising.com/2018/07/anbox-how-to-install-google-play-stor [6]:https://github.com/anbox/anbox/issues/118#issuecomment-295270113 [7]:https://github.com/anbox/anbox/blob/master/docs/install.md [8]:https://www.linuxuprising.com/2018/07/anbox-how-to-install-google-play-store.html?showComment=1533506821283#c4415289781078860898 -[9]:https://github.com/anbox/anbox/issues/118#issuecomment-295270113 \ No newline at end of file +[9]:https://github.com/anbox/anbox/issues/118#issuecomment-295270113 diff --git a/published/20180716 How To Find The Mounted Filesystem Type In Linux.md b/published/201811/20180716 How To Find The Mounted Filesystem Type In Linux.md similarity index 100% rename from published/20180716 How To Find The Mounted Filesystem Type In Linux.md rename to published/201811/20180716 How To Find The Mounted Filesystem Type In Linux.md diff --git a/published/20180723 Setting Up a Timer with systemd in Linux.md b/published/201811/20180723 Setting Up a Timer with systemd in Linux.md similarity index 100% rename from published/20180723 Setting Up a Timer with systemd in Linux.md rename to published/201811/20180723 Setting Up a Timer with systemd in Linux.md diff --git a/published/20180730 A single-user, lightweight OS for your next home project - Opensource.com.md b/published/201811/20180730 A single-user, lightweight OS for your next home project - Opensource.com.md similarity index 100% rename from published/20180730 A single-user, lightweight OS for your next home project - Opensource.com.md rename to published/201811/20180730 A single-user, lightweight OS for your next home project - Opensource.com.md diff --git a/published/20180801 5 of the Best Linux Games to Play in 2018.md b/published/201811/20180801 5 of the Best Linux Games to Play in 2018.md similarity index 100% rename from published/20180801 5 of the Best Linux Games to Play in 2018.md rename to published/201811/20180801 5 of the Best Linux Games to Play in 2018.md diff --git a/published/20180803 SDKMAN - A CLI Tool To Easily Manage Multiple Software Development Kits.md b/published/201811/20180803 SDKMAN - A CLI Tool To Easily Manage Multiple Software Development Kits.md similarity index 100% rename from published/20180803 SDKMAN - A CLI Tool To Easily Manage Multiple Software Development Kits.md rename to published/201811/20180803 SDKMAN - A CLI Tool To Easily Manage Multiple Software Development Kits.md diff --git a/published/201811/20180807 5 reasons the i3 window manager makes Linux better.md b/published/201811/20180807 5 reasons the i3 window manager makes Linux better.md new file mode 100644 index 0000000000..b9df0f4509 --- /dev/null +++ b/published/201811/20180807 5 reasons the i3 window manager makes Linux better.md @@ -0,0 +1,109 @@ +i3 窗口管理器使 Linux 更美好 +====== + +> 通过键盘操作的 i3 平铺窗口管理器使用 Linux 桌面。 + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/cloud-windows.png?itok=jd5sBNQH) + +Linux（和一般的开源软件）最美好的一点是自由 —— 可以在不同的替代方案中进行选择以满足我们的需求。 + +我使用 Linux 已经很长时间了，但我从来没有对可选用的桌面环境完全满意过。直到去年，[Xfce][1] 还是我认为在功能和性能之间的平和最接近满意的一个桌面环境。然后我发现了 [i3][2]，这是一个改变了我的生活的惊人的软件。 + +i3 是一个平铺窗口管理器。窗口管理器的目标是控制窗口系统中窗口的外观和位置。窗口管理器通常用作功能齐全的桌面环境 (如 GONME 或 Xfce ) 的一部分，但也有一些可以用作独立的应用程序。 + +平铺式窗口管理器会自动排列窗口，以不重叠的方式占据整个屏幕。其他流行的平铺式窗口管理器还有 [wmii][3] 和 [xmonad][4] 。 + +![i3 tiled window manager screenshot][6] + +*带有三个的 i3 屏幕截图* + +为了获得更好的 Linux 桌面体验，以下是我使用和推荐 i3 窗口管理器的五个首要原因。 + +### 1、极简艺术 + +i3 速度很快。它既不冗杂、也不花哨。它的设计简单而高效。作为开发人员，我重视这些功能，因为我可以使用更多的功能以丰富我最喜欢的开发工具，或者使用容器或虚拟机在本地测试内容。 + +此外， i3 是一个窗口管理器，与功能齐全的桌面环境不同，它并不规定您应该使用的应用程序。您是否想使用 Xfce 的 Thunar 作为文件管理器？GNOME 的 gedit 去编辑文本? i3 并不在乎。选择对您的工作流最有意义的工具，i3 将以相同的方式管理它们。 + +### 2、屏幕实际使用面积 + +作为平铺式窗口管理器，i3 将自动 “平铺”，以不重叠的方式定位窗口，类似于在墙上放置瓷砖。因为您不需要担心窗口定位，i3 一般会更好地利用您的屏幕空间。它还可以让您更快地找到您需要的东西。 + +对于这种情况有很多有用的例子。例如，系统管理员可以打开多个终端来同时监视或在不同的远程系统上工作；开发人员可以使用他们最喜欢的 IDE 或编辑器和几个终端来测试他们的程序。 + +此外，i3 具有灵活性。如果您需要为特定窗口提供更多空间，请启用全屏模式或切换到其他布局，如堆叠或选项卡式（标签式）。 + +### 3、键盘式工作流程 + +i3 广泛使用键盘快捷键来控制环境的不同方面。其中包括打开终端和其他程序、调整大小和定位窗口、更改布局，甚至退出 i3。当您开始使用 i3 时，您需要记住其中的一些快捷方式才能使用，随着时间的推移，您会使用更多的快捷方式。 + +主要好处是，您不需要经常在键盘和鼠标之间切换。通过练习，您将提高工作流程的速度和效率。 + +例如， 要打开新的终端，请按 `+`。由于窗口是自动定位的，您可以立即开始键入命令。结合一个很好的终端文本编辑器（如 Vim）和一个以面向键盘的浏览器，形成一个完全由键盘驱动的工作流程。 + +在 i3 中，您可以为所有内容定义快捷方式。下面是一些示例： + + * 打开终端 + * 打开浏览器 + * 更改布局 + * 调整窗口大小 + * 控制音乐播放器 + * 切换工作区 + +现在我已经习惯了这个工作形式，我已无法回到了常规的桌面环境。 + +### 4、灵活 + +i3 力求极简，使用很少的系统资源，但这并不意味着它不能变漂亮。i3 是灵活且可通过多种方式进行自定义以改善视觉体验。因为 i3 是一个窗口管理器，所以它没有提供启用自定义的工具，你需要外部工具来实现这一点。一些例子： + + * 用 `feh` 定义桌面的背景图片。 + * 使用合成器管理器，如 `compton` 以启用窗口淡入淡出和透明度等效果。 + * 用 `dmenu` 或 `rofi` 以启用可从键盘快捷方式启动的可自定义菜单。 + * 用 `dunst` 用于桌面通知。 + +i3 是可完全配置的，您可以通过更新默认配置文件来控制它的各个方面。从更改所有键盘快捷键，到重新定义工作区的名称，再到修改状态栏，您都可以使 i3 以任何最适合您需要的方式运行。 + +![i3 with rofi menu and dunst desktop notifications][8] + +*i3 与 `rofi` 菜单和 `dunst` 桌面通知。* + +最后，对于更高级的用户，i3 提供了完整的进程间通信（[IPC][9]）接口，允许您使用偏好的语言来开发脚本或程序，以实现更多的自定义选项。 + +### 5、工作空间 + +在 i3 中，工作区是对窗口进行分组的一种简单方法。您可以根据您的工作流以不同的方式对它们进行分组。例如，您可以将浏览器放在一个工作区上，终端放在另一个工作区上，将电子邮件客户端放在第三个工作区上等等。您甚至可以更改 i3 的配置，以便始终将特定应用程序分配给它们自己的工作区。 + +切换工作区既快速又简单。像 i3 中的惯例，使用键盘快捷方式执行此操作。按 `+num` 切换到工作区 `num` 。如果您养成了始终将应用程序组的窗口分配到同一个工作区的习惯，则可以在它们之间快速切换，这使得工作区成为非常有用的功能。 + +此外，还可以使用工作区来控制多监视器环境，其中每个监视器都有个初始工作区。如果切换到该工作区，则切换到该监视器，而无需让手离开键盘。 + +最后，i3 中还有另一种特殊类型的工作空间：the scratchpad（便笺簿）。它是一个不可见的工作区，通过按快捷方式显示在其他工作区的中间。这是一种访问您经常使用的窗口或程序的方便方式，如电子邮件客户端或音乐播放器。 + +### 尝试一下吧 + +如果您重视简洁和效率，并且不惮于使用键盘，i3 就是您的窗口管理器。有人说是为高级用户准备的，但情况不一定如此。你需要学习一些基本的快捷方式来度过开始的阶段，不久就会越来越自然并且不假思索地使用它们。 + +这篇文章只是浅浅谈及了 i3 能做的事情。欲了解更多详情，请参阅 [i3 的文档][10]。 + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/8/i3-tiling-window-manager + +作者：[Ricardo Gerardi][a] +选题：[lujun9972](https://github.com/lujun9972) +译者：[lixinyuxx](https://github.com/lixinyuxx) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/rgerardi +[1]:https://xfce.org/ +[2]:https://i3wm.org/ +[3]:https://code.google.com/archive/p/wmii/ +[4]:https://xmonad.org/ +[5]:/file/406476 +[6]:https://opensource.com/sites/default/files/uploads/i3_screenshot.png "i3 tiled window manager screenshot" +[7]:/file/405161 +[8]:https://opensource.com/sites/default/files/uploads/rofi_dunst.png "i3 with rofi menu and dunst desktop notifications" +[9]:https://i3wm.org/docs/ipc.html +[10]:https://i3wm.org/docs/userguide.html diff --git a/published/20180810 How To Quickly Serve Files And Folders Over HTTP In Linux.md b/published/201811/20180810 How To Quickly Serve Files And Folders Over HTTP In Linux.md similarity index 100% rename from published/20180810 How To Quickly Serve Files And Folders Over HTTP In Linux.md rename to published/201811/20180810 How To Quickly Serve Files And Folders Over HTTP In Linux.md diff --git a/published/20180811 Dropbox To End Sync Support For All Filesystems Except Ext4 on Linux.md b/published/201811/20180811 Dropbox To End Sync Support For All Filesystems Except Ext4 on Linux.md similarity index 100% rename from published/20180811 Dropbox To End Sync Support For All Filesystems Except Ext4 on Linux.md rename to published/201811/20180811 Dropbox To End Sync Support For All Filesystems Except Ext4 on Linux.md diff --git a/published/20180814 Top Linux developers- recommended programming books.md b/published/201811/20180814 Top Linux developers- recommended programming books.md similarity index 100% rename from published/20180814 Top Linux developers- recommended programming books.md rename to published/201811/20180814 Top Linux developers- recommended programming books.md diff --git a/translated/tech/20180816 An introduction to the Django Python web app framework.md b/published/201811/20180816 An introduction to the Django Python web app framework.md similarity index 56% rename from translated/tech/20180816 An introduction to the Django Python web app framework.md rename to published/201811/20180816 An introduction to the Django Python web app framework.md index dc9fd20449..1946f2bb6b 100644 --- a/translated/tech/20180816 An introduction to the Django Python web app framework.md +++ b/published/201811/20180816 An introduction to the Django Python web app framework.md @@ -1,141 +1,113 @@ Python Web 应用程序 Django 框架简介 ===== +> 在这个比较 Python 框架的最后一篇中，让我们看看 Django。 ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/web-spider-frame-framework.png?itok=Rl2AG2Dc) -在本系列（由四部分组成）的前三篇文章中，我们讨论了 [Pyramid][1], [Flask][2] 和 [Tornado][3] 这 3 个 Web 框架。我们已经构建了三次相同的应用程序，最终我们遇到了 [Django][4]。总的来说，Django 是目前 Python 开发人员使用的主要 Web 框架，并且不难看出原因。它擅长隐藏大量的配置逻辑，让你专注于能过够快速构建大型应用程序。 +在本系列（由四部分组成）的前三篇文章中，我们讨论了 [Pyramid][1]、[Flask][2] 和 [Tornado][3] 这 3 个 Web 框架。我们已经构建了三次相同的应用程序，最终我们遇到了 [Django][4]。总的来说，Django 是目前 Python 开发人员使用的主要 Web 框架，并且原因显而易见。它擅长隐藏大量的配置逻辑，让你专注于能够快速构建大型应用程序。 也就是说，当涉及到小型项目时，比如我们的待办事项列表应用程序，Django 可能有点像用消防水管来进行水枪大战。让我们来看看它们是如何结合在一起的。 ### 关于 Django -Django 将自己定位为“一个高级的 Python Web 框架，它鼓励快速开发和干净，实用的设计。它由经验丰富的开发人员构建，解决了 Web 开发的很多麻烦，因此你可以专注于编写应用程序而无需重新发明轮子”。它真的做到了！这个庞大的 Web 框架附带了非常多的工具，通常在开发过程中，如何将所有内容组合在一起协同工作可能是个谜。 +Django 将自己定位为“一个鼓励快速开发和整洁、实用的设计的高级 Python Web 框架。它由经验丰富的开发人员构建，解决了 Web 开发的很多麻烦，因此你可以专注于编写应用程序而无需重新发明轮子”。而且它确实做到了！这个庞大的 Web 框架附带了非常多的工具，以至于在开发过程中，如何将所有内容组合在一起协同工作可能是个谜。 -除了框架本身很大，Django 社区也是非常庞大的。事实上，它非常庞大和活跃，以至于有[一个网站][5]致力于为人们收集第三方包，这些第三方包可集成进 Django 来做一大堆事情。包括从身份验证和授权到完全基于 Django 的内容管理系统，电子商务附加组件以及与 Stripe（译注：美版“支付宝”）集成的所有内容。关于不要重新发明轮子：如果你想用 Django 完成一些事情，有人可能已经做过了，你只需将它集成进你的项目就行。 +除了框架本身很大，Django 社区也是非常庞大的。事实上，它非常庞大和活跃，以至于有[一个网站][5]专门用于为人们收集第三方包，这些第三方包可集成进 Django 来做一大堆事情。包括从身份验证和授权到完全基于 Django 的内容管理系统，电子商务附加组件以及与 Stripe（LCTT 译注：美版“支付宝”）集成的所有内容。至于不要重新发明轮子：如果你想用 Django 完成一些事情，有人可能已经做过了，你只需将它集成进你的项目就行。 -为此，我们希望使用 Django 构建 REST API，因此我们将利用流行的 [Django REST framework][6]。它的工作是将 Django 框架（Django 使用自己的模板引擎构建 HTML 页面）转换为专门用于有效地处理 REST 交互的系统。让我们开始吧。 +为此，我们希望使用 Django 构建 REST API，因此我们将使用流行的 [Django REST 框架][6]。它的工作是将 Django 框架（Django 使用自己的模板引擎构建 HTML 页面）转换为专门用于有效地处理 REST 交互的系统。让我们开始吧。 ### Django 启动和配置 ``` $ mkdir django_todo - $ cd django_todo - $ pipenv install --python 3.6 - $ pipenv shell - (django-someHash) $ pipenv install django djangorestframework - ``` 作为参考，我们使用的是 `django-2.0.7` 和 `djangorestframework-3.8.2`。 -与 Flask, Tornado 和 Pyramid 不同，我们不需要自己编写 `setup.py` 文件，我们并不是在做一个可安装的 Python 发行版。像很多事情一样，Django 以自己的方式处理这个问题。我们仍然需要一个 `requirements.txt` 文件来跟踪我们在其它地方部署的所有必要安装。但是，就 Django 项目中的目标模块而言，Django 会让我们列出我们想要访问的子目录，然后允许我们从这些目录中导入，就像它们是已安装的包一样。 +与 Flask, Tornado 和 Pyramid 不同，我们不需要自己编写 `setup.py` 文件，我们并不是在做一个可安装的 Python 发布版。像很多事情一样，Django 以自己的方式处理这个问题。我们仍然需要一个 `requirements.txt` 文件来跟踪我们在其它地方部署的所有必要安装。但是，就 Django 项目中的目标模块而言，Django 会让我们列出我们想要访问的子目录，然后允许我们从这些目录中导入，就像它们是已安装的包一样。 首先，我们必须创建一个 Django 项目。 -当我们安装了 Django 后，我们还安装了命令行脚本 `django-admin`。它的工作是管理所有与 Django 相关的命令，这些命令有助于我们将项目整合在一起，并在我们继续开发的过程中对其进行维护。`django-admin` 并不是让我们从头开始构建整个 Django 生态系统，而是让我们开始使用标准 Django 项目所需的所有必要文件（以及更多）。 +当我们安装了 Django 后，我们还安装了命令行脚本 `django-admin`。它的工作是管理所有与 Django 相关的命令，这些命令有助于我们将项目整合在一起，并在我们继续开发的过程中对其进行维护。`django-admin` 并不是让我们从头开始构建整个 Django 生态系统，而是让我们从标准 Django 项目所需的所有必要文件（以及更多）的基础上开始。 调用 `django-admin` 的 `start-project` 命令的语法是 `django-admin startproject <项目名称> <存放目录>`。我们希望文件存于当前的工作目录中，所以： + ``` (django-someHash) $ django-admin startproject django_todo . - ``` 输入 `ls` 将显示一个新文件和一个新目录。 + ``` (django-someHash) $ ls - manage.py   django_todo - ``` -`manage.py` 是一个可执行命令行 Python 文件，它最终成为 `django-admin` 的装饰器（to 校正：这里装饰器只是一个语义上的称呼，与 Python 的装饰器不同）。因此，它的工作与 `django-admin` 是一样的：帮助我们管理项目。因此得名 `manage.py`。 +`manage.py` 是一个可执行命令行 Python 文件，它最终成为 `django-admin` 的封装。因此，它的工作与 `django-admin` 是一样的：帮助我们管理项目。因此得名 `manage.py`。 它在 `django_todo` 目录里创建了一个新目录 `django_todo`，其代表了我们项目的配置根目录。现在让我们深入研究一下。 ### 配置 Django -可以将 `django_todo` 目录称为“配置根”，我们的意思是这个目录包含了通常配置 Django 项目所需的文件。几乎所有这个目录之外的内容都只关注与项目模型，视图，路由等相关的“业务逻辑”。所有连接项目的点都将在这里出现。 +可以将 `django_todo` 目录称为“配置根目录”，我们的意思是这个目录包含了通常配置 Django 项目所需的文件。几乎所有这个目录之外的内容都只关注与项目模型、视图、路由等相关的“业务逻辑”。所有连接项目的点都将在这里出现。 在 `django_todo` 目录中调用 `ls` 会显示以下四个文件： + ``` (django-someHash) $ cd django_todo - (django-someHash) $ ls - __init__.py settings.py urls.py     wsgi.py - ``` * `__init__.py` 文件为空，之所以存在是为了将此目录转换为可导入的 Python 包。 - * `settings.py` 是设置大多数配置项的地方。例如项目是否处于 DEBUG 模式，正在使用哪些数据库，Django 应该定位文件的位置等等。它是配置根目录的“主要配置”部分，我们将在一会深入研究。 - * `urls.py` 顾名思义就是设置 URL 的地方。虽然我们不必在此文件中显式写入项目的每个 URL，但我们需要让此文件知道在其他任何地方已声明的 URL。如果此文件未指向其它 URL，则那些 URL 就不存在。 - - * `wsgi.py` 用于在生产环境中提供应用程序。就像 Pyramid, Tornado 和 Flask 暴露了一些 “app” 对象一样，它们用来提供配置好的应用程序，Django 也必须暴露一个，就是在这里完成的。它可以和 [Gunicorn][7], [Waitress][8] 或者 [uWSGI][9] 一起配合来提供服务。 + * `wsgi.py` 用于在生产环境中提供应用程序。就像 Pyramid、 Tornado 和 Flask 暴露了一些 “app” 对象一样，它们用来提供配置好的应用程序，Django 也必须暴露一个，就是在这里完成的。它可以和 [Gunicorn][7]、[Waitress][8] 或者 [uWSGI][9] 一起配合来提供服务。 #### 设置 settings -看一看 `settings.py`，它里面有大量的配置项，那些只是默认值！这甚至不包括数据库，静态文件，媒体文件，任何集成的钩子，或者可以配置 Django 项目的任何其它几种方式。让我们从上到下看看有什么： - - * `BASE_DIR` 设置目录的绝对路径，或者是 `manage.py` 所在的目录。这对于定位文件非常有用。 - - * `SECRET_KEY` 是用于 Django 项目中加密签名的密钥。在实际中，它用于会话，cookie，CSRF 保护和身份验证令牌等。最好在第一次提交之前，尽快应该更改 `SECRET_KEY` 的值并将其放置到环境变量中。 - - * `DEBUG` 告诉 Django 是以开发模式还是生产模式运行项目。这是一个非常关键的区别。 - - * 在开发模式下，当弹出一个错误时，Django 将显示导致错误的完整堆栈跟踪，以及运行项目所涉及的所有设置和配置。如果在生产环境中将 `DEBUG` 设置为 `True`，这可能是一个巨大的安全问题。 +看一看 `settings.py`，它里面有大量的配置项，那些只是默认值！这甚至不包括数据库、静态文件、媒体文件、任何集成的钩子，或者可以配置 Django 项目的任何其它几种方式。让我们从上到下看看有什么： +* `BASE_DIR` 设置目录的绝对路径，或者是 `manage.py` 所在的目录。这对于定位文件非常有用。 +* `SECRET_KEY` 是用于 Django 项目中加密签名的密钥。在实际中，它用于会话、cookie、CSRF 保护和身份验证令牌等。最好在第一次提交之前，尽快应该更改 `SECRET_KEY` 的值并将其放置到环境变量中。 +* `DEBUG` 告诉 Django 是以开发模式还是生产模式运行项目。这是一个非常关键的区别。 + * 在开发模式下，当弹出一个错误时，Django 将显示导致错误的完整堆栈跟踪，以及运行项目所涉及的所有设置和配置。如果在生产环境中将 `DEBUG` 设置为 `True`，这可能成为一个巨大的安全问题。 * 在生产模式下，当出现问题时，Django 会显示一个简单的错误页面，即除错误代码外不提供任何信息。 - * 保护我们项目的一个简单方法是将 `DEBUG` 设置为环境变量，如 `bool(os.environ.get('DEBUG', ''))`。 - * `ALLOWED_HOSTS` 是应用程序提供服务的主机名的列表。在开发模式中，这可能是空的，但是在生产中，如果为项目提供服务的主机不在 ALLOWED_HOSTS 列表中，Django 项目将无法运行。这是设置为环境变量的另一种情况。 - - * `INSTALLED_APPS` 是我们的 Django 项目可以访问的 Django "apps" 列表（将它们视为子目录，稍后会详细介绍）。默认情况下，它将提供： - * 内置的 Django admin 网站 +* `ALLOWED_HOSTS` 是应用程序提供服务的主机名的列表。在开发模式中，这可能是空的；但是在生产环境中，如果为项目提供服务的主机不在 `ALLOWED_HOSTS` 列表中，Django 项目将无法运行。这是设置为环境变量的另一种情况。 +* `INSTALLED_APPS` 是我们的 Django 项目可以访问的 Django “apps” 列表（将它们视为子目录，稍后会详细介绍）。默认情况下，它将提供： + * 内置的 Django 管理网站 * Django 的内置认证系统 * Django 的数据模型通用管理器 * 会话管理 * Cookie 和基于会话的消息传递 - * 站点固有的静态文件的用法，比如 `css` 文件，`js` 文件，任何属于我们网站设计的图片等。 - - * `MIDDLEWARE` 顾名思义：帮助 Django 项目运行的中间件。其中很大一部分用于处理各种类型的安全，尽管我们可以根据需要添加其它中间件。 - - * `ROOT_URLCONF` 设置基本 URL 配置文件的导入路径。还记得我们之前见过的那个 `urls.py` 吗？默认情况下，Django 指向该文件以此来收集所有的 URL。如果我们想让 Django 在其它地方寻找，我们将在这里设置 URL 位置的导入路径。 - - * `TEMPLATES` 是 Django 用于我们网站前端的模板引擎列表，假如我们依靠 Django 来构建我们的 HTML。我们在这里不需要，那就无关紧要了。 - - * `WSGI_APPLICATION` 设置我们的 WSGI 应用程序的导入路径 - 在生产环境下使用的东西。默认情况下，它指向 `wsgi.py` 中的 `application` 对象。这很少（如果有的话）需要修改。 - - * `DATABASES` 设置 Django 项目将访问那些数据库。必须设置 `default` 数据库。我们可以通过名称设置别的数据库，只要我们提供 `HOST`, `USER`, `PASSWORD`, `PORT`, 数据库名称 `NAME` 和合适的 `ENGINE`。可以想象，这些都是敏感的信息，因此最好将它们隐藏在环境变量中。[查看 Django 文档][10]了解更多详情。 - - * 注意：如果不是提供数据库的单个部分，而是提供完整的数据库 URL，请查看 [dj_database_url][11]。 - - * `AUTH_PASSWORD_VALIDATORS` 实际上是运行以检查输入密码的函数列表。默认情况下我们有一些，但是如果我们有其它更复杂的验证需求：不仅仅是检查密码是否与用户的属性匹配，是否超过最小长度，是否是 1000 个最常用的密码之一，或者密码完全是数字，我们可以在这里列出它们。 - - * `LANGUAGE_CODE` 设置网站的语言。默认情况下它是美国英语，但我们可以将其切换为其它语言。 - - * `TIME_ZONE` 是我们 Django 项目后中自动生成的时间戳的时区。我强调坚持使用 UTC 并在其它地方执行任何特定于时区的处理，而不是尝试重新配置此设置。正如[这篇文章][12] 所述，UTC 是所有时区的共同点，因为不需要担心偏移。如果偏移很重要，我们可以根据需要使用与 UTC 的适当偏移来计算它们。 - - * `USE_I18N` 将让 Django 使用自己的翻译服务来为前端翻译字符串。I18N = 国际化（“i” 和 “n” 之间的 18 个字符）。 - - * `USE_L10N` (L10N = 本地化[在 "l" 和 "n" 之间有 10 个字符]) 如果设置为 `True`，那么将使用数据的公共本地格式。一个很好的例子是日期：在美国它是 MM-DD-YYYY。在欧洲，日期往往写成 DD-MM-YYYY。 - - * `STATIC_URL` 是用于提供静态文件的大量设置的一部分。我们将构建一个 REST API，因此我们不需要担心静态文件。通常，这会为每个静态文件的域名设置根路径。所以，如果我们有一个徽标图像，那就是 `http:////logo.gif`。 + * 站点固有的静态文件的用法，比如 `css` 文件、`js` 文件、任何属于我们网站设计的图片等。 +* `MIDDLEWARE` 顾名思义：帮助 Django 项目运行的中间件。其中很大一部分用于处理各种类型的安全，尽管我们可以根据需要添加其它中间件。 +* `ROOT_URLCONF` 设置基本 URL 配置文件的导入路径。还记得我们之前见过的那个 `urls.py` 吗？默认情况下，Django 指向该文件以此来收集所有的 URL。如果我们想让 Django 在其它地方寻找，我们将在这里设置 URL 位置的导入路径。 +* `TEMPLATES` 是 Django 用于我们网站前端的模板引擎列表，假如我们依靠 Django 来构建我们的 HTML。我们在这里不需要，那就无关紧要了。 +* `WSGI_APPLICATION` 设置我们的 WSGI 应用程序的导入路径 —— 在生产环境下使用的东西。默认情况下，它指向 `wsgi.py` 中的 `application` 对象。这很少（如果有的话）需要修改。 +* `DATABASES` 设置 Django 项目将访问那些数据库。必须设置 `default` 数据库。我们可以通过名称设置别的数据库，只要我们提供 `HOST`、`USER`、`PASSWORD`、`PORT`、数据库名称 `NAME` 和合适的 `ENGINE`。可以想象，这些都是敏感的信息，因此最好将它们隐藏在环境变量中。[查看 Django 文档][10]了解更多详情。 + * 注意：如果不是提供数据库的每个单个部分，而是提供完整的数据库 URL，请查看 [dj_database_url][11]。 +* `AUTH_PASSWORD_VALIDATORS` 实际上是运行以检查输入密码的函数列表。默认情况下我们有一些，但是如果我们有其它更复杂的验证需求：不仅仅是检查密码是否与用户的属性匹配，是否超过最小长度，是否是 1000 个最常用的密码之一，或者密码完全是数字，我们可以在这里列出它们。 +* `LANGUAGE_CODE` 设置网站的语言。默认情况下它是美国英语，但我们可以将其切换为其它语言。 +* `TIME_ZONE` 是我们 Django 项目后中自动生成的时间戳的时区。我强调坚持使用 UTC 并在其它地方执行任何特定于时区的处理，而不是尝试重新配置此设置。正如[这篇文章][12] 所述，UTC 是所有时区的共同点，因为不需要担心偏移。如果偏移很重要，我们可以根据需要使用与 UTC 的适当偏移来计算它们。 +* `USE_I18N` 将让 Django 使用自己的翻译服务来为前端翻译字符串。I18N = 国际化（internationalization，“i” 和 “n” 之间共 18 个字符）。 +* `USE_L10N` L10N = 本地化（localization，在 "l" 和 "n" 之间共 10 个字符) 。如果设置为 `True`，那么将使用数据的公共本地格式。一个很好的例子是日期：在美国它是 MM-DD-YYYY。在欧洲，日期往往写成 DD-MM-YYYY。 +* `STATIC_URL` 是用于提供静态文件的主体部分。我们将构建一个 REST API，因此我们不需要考虑静态文件。通常，这会为每个静态文件的域名设置根路径。所以，如果我们有一个 Logo 图像，那就是 `http:////logo.gif`。 默认情况下，这些设置已准备就绪。我们必须改变的一个选项是 `DATABASES` 设置。首先，我们创建将要使用的数据库： + ``` (django-someHash) $ createdb django_todo - ``` -我们想要像使用 Flask, Pyramid 和 Tornado 一样使用 PostgreSQL 数据库，这意味着我们必须更改 `DATABASES` 设置以允许我们的服务器访问 PostgreSQL 数据库。首先是引擎。默认情况下，数据库引擎是 `django.db.backends.sqlite3`，我们把它改成 `django.db.backends.postgresql`。 +我们想要像使用 Flask、Pyramid 和 Tornado 一样使用 PostgreSQL 数据库，这意味着我们必须更改 `DATABASES` 设置以允许我们的服务器访问 PostgreSQL 数据库。首先是引擎。默认情况下，数据库引擎是 `django.db.backends.sqlite3`，我们把它改成 `django.db.backends.postgresql`。 -有关 Django 可用引擎的更多信息，[查看文档][13]。请注意，尽管技术上可以将 NoSQL 解决方案整合到 Django 项目中，但为了开箱即用，Django 强烈偏向于 SQL 解决方案。 +有关 Django 可用引擎的更多信息，[请查看文档][13]。请注意，尽管技术上可以将 NoSQL 解决方案整合到 Django 项目中，但为了开箱即用，Django 强烈偏向于 SQL 解决方案。 接下来，我们必须为连接参数的不同部分指定键值对。 @@ -145,90 +117,65 @@ __init__.py settings.py urls.py     wsgi.py * `HOST` 是数据库的主机。当我们在本地开发时，`localhost` 或 `127.0.0.1` 都将起作用。 * `PORT` 是我们为 Postgres 开放的端口，它通常是 `5432`。 -`settings.py` 希望我们为每个键提供字符串值。但是，这是高度敏感的信息。这对任何负责任的开发人员都不起作用。有几种方法可以解决这个问题，一种是我们需要设置环境变量。 +`settings.py` 希望我们为每个键提供字符串值。但是，这是高度敏感的信息。任何负责任的开发人员都不应该这样做。有几种方法可以解决这个问题，一种是我们需要设置环境变量。 + ``` DATABASES = { -     'default': { -         'ENGINE': 'django.db.backends.postgresql', -         'NAME': os.environ.get('DB_NAME', ''), -         'USER': os.environ.get('DB_USER', ''), -         'PASSWORD': os.environ.get('DB_PASS', ''), -         'HOST': os.environ.get('DB_HOST', ''), -         'PORT': os.environ.get('DB_PORT', ''), -     } - } - ``` -在继续之前，请确保设置环境变量或 Django 不起作用（to 校正：这里不清楚原文的意思，什么叫 django 不起作用）。此外，我们需要在此环境中安装 `psycopg2`，以便我们可以与数据库通信。 +在继续之前，请确保设置环境变量，否则 Django 将无法工作。此外，我们需要在此环境中安装 `psycopg2`，以便我们可以与数据库通信。 ### Django 路由和视图 -让我们在这个项目中实现一些函数。我们将使用 Django REST Framework 来构建 REST API，所以我们必须确保在 `settings.py` 中将 `rest_framework` 添加到 `INSTALLED_APPS` 的末尾。 +让我们在这个项目中实现一些函数。我们将使用 Django REST 框架来构建 REST API，所以我们必须确保在 `settings.py` 中将 `rest_framework` 添加到 `INSTALLED_APPS` 的末尾。 + ``` INSTALLED_APPS = [ -     'django.contrib.admin', -     'django.contrib.auth', -     'django.contrib.contenttypes', -     'django.contrib.sessions', -     'django.contrib.messages', -     'django.contrib.staticfiles', -     'rest_framework' - ] - ``` -虽然 Django REST Framework 并不专门需要基于类的视图（如 Tornado）来处理传入的请求，但类是编写视图的首选方法。让我们来定义一个类视图。 +虽然 Django REST 框架并不专门需要基于类的视图（如 Tornado）来处理传入的请求，但类是编写视图的首选方法。让我们来定义一个类视图。 + +让我们在 `django_todo` 创建一个名为 `views.py` 的文件。在 `views.py` 中，我们将创建 “Hello, world!” 视图。 -让我们在 `django_todo` 创建一个名为 `views.py` 的文件。在 `views.py` 中，我们将创建 "Hello, world!" 视图。 ``` -# django_todo/views.py - +# in django_todo/views.py from rest_framework.response import JsonResponse - from rest_framework.views import APIView - class HelloWorld(APIView): - -    def get(self, request, format=None): - -        """Print 'Hello, world!' as the response body.""" - -        return JsonResponse("Hello, world!") - + def get(self, request, format=None): + """Print 'Hello, world!' as the response body.""" + return JsonResponse("Hello, world!") ``` -每个 Django REST Framework 基于类的视图都直接或间接地继承自 `APIView`。`APIView` 处理大量的东西，但为了达到我们的目的，它做了以下特定的事情： +每个 Django REST 框架基于类的视图都直接或间接地继承自 `APIView`。`APIView` 处理大量的东西，但针对我们的用途，它做了以下特定的事情： - * 根据 HTTP 方法（例如 GET, POST, PUT, DELETE）来设置引导对应请求所需的方法 - + * 根据 HTTP 方法（例如 GET、POST、PUT、DELETE）来设置引导对应请求所需的方法 * 用我们需要的所有数据和属性来填充 `request` 对象，以便解析和处理传入的请求 + * 采用 `Response` 或 `JsonResponse`，每个调度方法（即名为 `get`、`post`、`put`、`delete` 的方法）返回并构造格式正确的 HTTP 响应。 - * 采用 `Response` 或 `JsonResponse`，每个调度方法（即名为 `get`, `post`, `put`, `delete` 的方法）返回并构造格式正确的 HTTP 响应。 - -终于，我们有一个视图了!它本身没有任何作用，我们需要将它连接到路由。 +终于，我们有一个视图了！它本身没有任何作用，我们需要将它连接到路由。 如果我们跳转到 `django_todo/urls.py`，我们会到达默认的 URL 配置文件。如前所述：如果 Django 项目中的路由不包含在此处，则它不存在。 -我们在给定的 `urlpatterns` 列表中添加所需的 URL。默认情况下，我们有一个 url，它里面包含一整套 URL 用于 Django 的内置管理后端系统，但是我们会删除它。 +我们在给定的 `urlpatterns` 列表中添加所需的 URL。默认情况下，我们有一整套 URL 用于 Django 的内置管理后端系统。我们会完全删除它。 我们还得到一些非常有用的文档字符串，它告诉我们如何向 Django 项目添加路由。我们需要调用 `path()`，伴随三个参数： @@ -236,76 +183,63 @@ class HelloWorld(APIView): * 处理该路由的视图函数（只能有一个函数！） * 在 Django 项目中路由的名称 -让我们导入 `HelloWorld` 视图并将其附加到主路径 `"/"` 。我们可以从 `urlpatterns` 中删除 `admin` 的路径，因为我们不会使用它。 +让我们导入 `HelloWorld` 视图并将其附加到主路径 `/` 。我们可以从 `urlpatterns` 中删除 `admin` 的路径，因为我们不会使用它。 ``` # django_todo/urls.py, after the big doc string - from django.urls import path - from django_todo.views import HelloWorld - - urlpatterns = [ -     path('', HelloWorld.as_view(), name="hello"), - ] - ``` -好吧，这里有一点不同。我们指定的路由只是一个空白字符串，为什么它会工作？Django 假设我们声明的每个路由都以一个前导斜杠开头，我们只是在初始域名后指定资源路由。如果一条路由没有去往一个特定的资源，而只是一个主页，那么该路由是 `""`，或者实际上是“没有资源”。 +好吧，这里有一点不同。我们指定的路由只是一个空白字符串，为什么它会工作？Django 假设我们声明的每个路由都以一个前导斜杠开头，我们只是在初始域名后指定资源路由。如果一条路由没有去往一个特定的资源，而只是一个主页，那么该路由是 `''`，实际上是“没有资源”。 `HelloWorld` 视图是从我们刚刚创建的 `views.py` 文件导入的。为了执行此导入，我们需要更新 `settings.py` 中的 `INSTALLED_APPS` 列表使其包含 `django_todo`。是的，这有点奇怪。以下是一种理解方式。 `INSTALLED_APPS` 指的是 Django 认为可导入的目录或包的列表。它是 Django 处理项目的各个组件的方式，比如安装了一个包，而不需要经过 `setup.py` 的方式。我们希望将 `django_todo` 目录视为可导入的包，因此我们将该目录包含在 `INSTALLED_APPS` 中。现在，在该目录中的任何模块也是可导入的。所以我们得到了我们的视图。 -`path` 函数只将视图函数作为第二个参数，而不仅仅是基于类的视图。幸运的是，所有有效的基于 Django 类的视图都包含 `.as_view()` 方法。它的工作是将基于类的视图的所有优点汇总到一个视图函数中并返回该视图函数。所以，我们永远不必担心转换的工作。相反，我们只需要考虑业务逻辑，让 Django 和 Django REST Framework 处理剩下的事情。 +`path` 函数只将视图函数作为第二个参数，而不仅仅是基于类的视图。幸运的是，所有有效的基于 Django 类的视图都包含 `.as_view()` 方法。它的工作是将基于类的视图的所有优点汇总到一个视图函数中并返回该视图函数。所以，我们永远不必担心转换的工作。相反，我们只需要考虑业务逻辑，让 Django 和 Django REST 框架处理剩下的事情。 让我们在浏览器中打开它！ Django 提供了自己的本地开发服务器，可通过 `manage.py` 访问。让我们切换到包含 `manage.py` 的目录并输入： + ``` (django-someHash) $ ./manage.py runserver Performing system checks... System check identified no issues (0 silenced). - August 01, 2018 - 16:47:24 - Django version 2.0.7, using settings 'django_todo.settings' - Starting development server at http://127.0.0.1:8000/ - Quit the server with CONTROL-C. - ``` -当 `runserver` 执行时，Django 会检查以确保项目（或多或少）正确连接在一起。这不是万无一失的，但确实会发现一些明显的问题。如果我们的数据库与代码不同步，它会通知我们。毫无遗问，因为我们没有将任何应用程序的东西提交到我们的数据库，但现在这样做还是可以的。让我们访问 `http://127.0.0.1:8000` 来查看 `HelloWorld` 视图的输出。 +当 `runserver` 执行时，Django 会检查以确保项目（或多或少）正确连接在一起。这不是万无一失的，但确实会发现一些明显的问题。如果我们的数据库与代码不同步，它会通知我们。毫无疑问，因为我们没有将任何应用程序的东西提交到我们的数据库，但现在这样做还是可以的。让我们访问 `http://127.0.0.1:8000` 来查看 `HelloWorld` 视图的输出。 -咦？这不是我们在 Pyramid, Flask 和 Tornado 中看到的明文数据。当使用 Django REST Framework 时，HTTP 响应（在浏览器中查看时）是这样呈现的 HTML，以红色显示我们的实际 JSON 响应。 +咦？这不是我们在 Pyramid、Flask 和 Tornado 中看到的明文数据。当使用 Django REST 框架时，HTTP 响应（在浏览器中查看时）是这样呈现的 HTML，以红色显示我们的实际 JSON 响应。 但不要担心！如果我们在命令行中使用 `curl` 快速访问 `http://127.0.0.1:8000`，我们就不会得到任何花哨的 HTML，只有内容。 + ``` # 注意：在不同的终端口窗口中执行此操作，在虚拟环境之外 - $ curl http://127.0.0.1:8000 - "Hello, world!" - ``` 棒极了！ -Django REST Framework 希望我们在使用浏览器浏览时拥有一个人性化的界面。这是有道理的，如果在浏览器中查看 JSON，通常是因为人们想要检查它是否正确，或者在设计一些消费者 API 时想要了解 JSON 响应。这很像你从 [Postman][14] 中获得的东西。 +Django REST 框架希望我们在使用浏览器浏览时拥有一个人性化的界面。这是有道理的，如果在浏览器中查看 JSON，通常是因为人们想要检查它是否正确，或者在设计一些消费者 API 时想要了解 JSON 响应。这很像你从 [Postman][14] 中获得的东西。 无论哪种方式，我们都知道我们的视图工作了！酷！让我们概括一下我们做过的事情： 1. 使用 `django-admin startproject <项目名称>` 开始一个项目 - 2. 使用环境变量来更新 `django_todo/settings.py` 中的 `DEBUG`, `SECRET_KEY`，还有 `DATABASES` 字典 - 3. 安装 `Django REST Framework`，并将它添加到 `INSTALLED_APPS` - 4. 创建 `django_todo/views.py` 来包含我们的第一个类视图，它返回响应 "Hello, world!" + 2. 使用环境变量来更新 `django_todo/settings.py` 中的 `DEBUG`、`SECRET_KEY`，还有 `DATABASES` 字典 + 3. 安装 Django REST 框架，并将它添加到 `INSTALLED_APPS` + 4. 创建 `django_todo/views.py` 来包含我们的第一个类视图，它返回响应 “Hello, world!” 5. 更新 `django_todo/urls.py`，其中包含我们的根路由 6. 在 `django_todo/settings.py` 中更新 `INSTALLED_APPS` 以包含 `django_todo` 包 @@ -313,115 +247,88 @@ Django REST Framework 希望我们在使用浏览器浏览时拥有一个人性 现在让我们来创建数据模型吧。 -Django 项目的整个基础架构都是围绕数据模型构建的，它是这样编写的，因此每个数据模型够可以拥有自己的小天地，拥有自己的视图，自己与其资源相关的 URL 集合，甚至是自己的测试（如果我们需要（to 校正：这里？？？））。 +Django 项目的整个基础架构都是围绕数据模型构建的，它是这样编写的，每个数据模型够可以拥有自己的小天地，拥有自己的视图，自己与其资源相关的 URL 集合，甚至是自己的测试（如果我们想要的话）。 -如果我们想构建一个简单的 Django 项目，我们可以通过在 `django_todo` 目录中编写我们自己的 `models.py` 文件并将其导入我们的视图来避免这种情况。但是，我们试图以“正确”的方式编写 Django 项目，因此我们应该尽可能地将模型分成 Django 方式的包（to 校正：这里 Django Way™ 有点懵）。 +如果我们想构建一个简单的 Django 项目，我们可以通过在 `django_todo` 目录中编写我们自己的 `models.py` 文件并将其导入我们的视图来避免这种情况。但是，我们想以“正确”的方式编写 Django 项目，因此我们应该尽可能地将模型拆分成符合 Django Way™（Django 风格）的包。 -Django Way 涉及创建所谓的 Django “apps”，它本身并不是单独的应用程序，它们没有自己的设置和诸如此类的东西（虽然它们也可以）。但是，它们可以拥有一个人们可能认为属于独立应用程序的东西： +Django Way 涉及创建所谓的 Django “应用程序”，它本身并不是单独的应用程序，它们没有自己的设置和诸如此类的东西（虽然它们也可以）。但是，它们可以拥有一个人们可能认为属于独立应用程序的东西： - * 一组自包含的 URL - * 一组自包含的 HTML 模板（如果我们想要提供 HTML） + * 一组自建的 URL + * 一组自建的 HTML 模板（如果我们想要提供 HTML） * 一个或多个数据模型 - * 一套自包含的视图 - * 一套自包含的测试 + * 一套自建的视图 + * 一套自建的测试 -它们是独立的，因此可以像独立应用程序一样轻松共享。实际上，Django REST Framework 是 Django app 的一个例子。它包含自己的视图和 HTML 模板，用于提供我们的 JSON。我们只是利用这个 Django app 将我们的项目变成一个全面的 RESTful API 而不用那么麻烦。 +它们是独立的，因此可以像独立应用程序一样轻松共享。实际上，Django REST 框架是 Django 应用程序的一个例子。它包含自己的视图和 HTML 模板，用于提供我们的 JSON。我们只是利用这个 Django 应用程序将我们的项目变成一个全面的 RESTful API 而不用那么麻烦。 + +要为我们的待办事项列表项创建 Django 应用程序，我们将要使用 `manage.py` 的 `startapp` 命令。 -要为我们的待办事项列表项创建 Django app，我们将要使用 `manage.py` 伴随参数 `startapp`。 ``` (django-someHash) $ ./manage.py startapp todo - ``` `startapp` 命令成功执行后没有输出。我们可以通过使用 `ls` 来检查它是否完成它应该做的事情。 + ``` (django-someHash) $ ls - Pipfile      Pipfile.lock django_todo  manage.py    todo - ``` 看看：我们有一个全新的 `todo` 目录。让我们看看里面! + ``` (django-someHash) $ ls todo - __init__.py admin.py    apps.py     migrations  models.py   tests.py    views.py - ``` 以下是 `manage.py startapp` 创建的文件： - * `__init__.py` 是空文件。它之所以存在是因为此目录可看作是模型，视图等的有效导入路径。 - - * `admin.py` 不是空文件。它用于在 Django admin 中格式化（to 校正：格式化可能欠妥）这个应用程序的模型，我们在本文中没有涉及到它。 - - * `apps.py` 这里基本不起作用。它有助于格式化 Django admin 的模型。 - - * `migrations` 是一个包含我们数据模型快照的目录。它用于更新数据库。这是内置数据库管理的少数几个框架之一，其中一部分允许我们更新数据库，而不必拆除它并重建它以更改模式。 - + * `__init__.py` 是空文件。它之所以存在是因为此目录可看作是模型、视图等的有效导入路径。 + * `admin.py` 不是空文件。它用于在 Django admin 中规范化这个应用程序的模型，我们在本文中没有涉及到它。 + * `apps.py` 这里基本不起作用。它有助于规范化 Django admin 的模型。 + * `migrations` 是一个包含我们数据模型快照的目录。它用于更新数据库。这是少数几个内置了数据库管理的框架之一，其中一部分允许我们更新数据库，而不必拆除它并重建它以更改 Schema。 * `models.py` 是数据模型所在。 - * `tests.py` 是测试所在的地方，如果我们需要写测试。 + * `views.py` 用于我们编写的与此应用程序中的模型相关的视图。它们不是一定得写在这里。例如，我们可以在 `django_todo/views.py` 中写下我们所有的视图。但是，它在这个应用程序中更容易将我们的概念理清。在覆盖了许多概念的扩展应用程序的关系之间会变得更加密切。 - * `views.py` 用于我们编写的与此 app 中的模型相关的视图。它们不是一定得写在这里。例如，我们可以在 `django_todo/views.py` 中写下我们所有的视图。但是，它在这个 app 中更容易将我们的问题分开。这与覆盖许多概念空间的扩展应用程序之间的关系更加密切。 +它并没有为这个应用程序创建 `urls.py` 文件，但我们可以自己创建。 -它并没有为这个 app 创建 `urls.py` 文件，但我们可以自己创建。 ``` (django-someHash) $ touch todo/urls.py - ``` 在继续之前，我们应该帮自己一个忙，将这个新 Django 应用程序添加到 `django_todo/settings.py` 中的 `INSTALLED_APPS` 列表中。 + ``` # settings.py - INSTALLED_APPS = [ -     'django.contrib.admin', -     'django.contrib.auth', -     'django.contrib.contenttypes', -     'django.contrib.sessions', -     'django.contrib.messages', -     'django.contrib.staticfiles', -     'rest_framework', -     'django_todo', -     'todo' # <--- 添加了这行 - ] - ``` -检查 `todo / models.py` 发现 `manage.py` 已经为我们编写了一些代码。不同于在 Flask, Tornado 和 Pyramid 实现中创建模型的方式，Django 不利用第三方来管理数据库会话或构建其对象实例。它全部归入 Django 的 `django.db.models` 子模块。 +检查 `todo/models.py` 发现 `manage.py` 已经为我们编写了一些代码。不同于在 Flask、Tornado 和 Pyramid 实现中创建模型的方式，Django 不利用第三方来管理数据库会话或构建其对象实例。它全部归入 Django 的 `django.db.models` 子模块。 然而，建立模型的方式或多或少是相同的。要在 Django 中创建模型，我们需要构建一个继承自 `models.Model` 的 `class`，将应用于该模型实例的所有字段都应视为类属性。我们不像过去那样从 SQLAlchemy 导入列和字段类型，而是直接从 `django.db.models` 导入。 + ``` # todo/models.py - from django.db import models - class Task(models.Model): -     """Tasks for the To Do list.""" -     name = models.CharField(max_length=256) -     note = models.TextField(blank=True, null=True) -     creation_date = models.DateTimeField(auto_now_add=True) -     due_date = models.DateTimeField(blank=True, null=True) -     completed = models.BooleanField(default=False) - ``` 虽然 Django 的需求和基于 SQLAlchemy 的系统之间存在一些明显的差异，但总体内容和结构或多或少相同。让我们来指出这些差异。 @@ -436,204 +343,140 @@ class Task(models.Model): `DateTime` 字段增加了一些属性，并且能够为我们做一些工作，使得我们不必修改类的 `__init__` 方法。对于 `creation_date` 字段，我们指定 `auto_now_add = True`。在实际意义上意味着，当创建一个新模型实例时，Django 将自动记录现在的日期和时间作为该字段的值。这非常方便！ -当 `auto_now_add` 及其类似属性 `auto_now` 都没被设置为 `True`时，`DateTimeField` 会像其它字段一样期待数据。它需要提供一个适当的 `datetime` 对象才能生效。`due_date` 列的 `blank` 和 `null` 属性都设置为 `True`，这样待办事项列表中的项目就可以成为将来某个时间点完成，没有确定的日期或时间。 +当 `auto_now_add` 及其类似属性 `auto_now` 都没被设置为 `True` 时，`DateTimeField` 会像其它字段一样需要预期的数据。它需要提供一个适当的 `datetime` 对象才能生效。`due_date` 列的 `blank` 和 `null` 属性都设置为 `True`，这样待办事项列表中的项目就可以成为将来某个时间点完成，没有确定的日期或时间。 `BooleanField` 最终可以取两个值：`True` 或 `False`。这里，默认值设置为 `False`。 #### 管理数据库 -如前所述，Django 有自己的数据库管理方式。我们可以利用 Django 提供的 `manage.py` 脚本，而不必编写任何关于数据库的代码。它不仅可以管理我们数据库的表格构建，还可以管理我们希望对这些表格进行的任何更新，而不必将整个事情搞砸！ +如前所述，Django 有自己的数据库管理方式。我们可以利用 Django 提供的 `manage.py` 脚本，而不必编写任何关于数据库的代码。它不仅可以管理我们数据库的表的构建，还可以管理我们希望对这些表进行的任何更新，而不必将整个事情搞砸！ + +因为我们构建了一个新模型，所以我们需要让数据库知道它。首先，我们需要将与此模型对应的模式放入代码中。`manage.py` 的 `makemigrations` 命令对我们构建的模型类及其所有字段进行快照。它将获取该信息并将其打包成一个 Python 脚本，该脚本将存在于特定 Django 应用程序的 `migrations` 目录中。永远没有理由直接运行这个迁移脚本。它的存在只是为了让 Django 可以使用它作为更新数据库表的基础，或者在我们更新模型类时继承信息。 -因为我们构建了一个新模型，所以我们需要让数据库知道它。首先，我们需要将与此模型对应的模式放入代码中。`manage.py` 的 `makemigrations` 命令对我们构建的模型类及其所有字段进行快照。它将获取该信息并将其打包成一个 Python 脚本，该脚本将存在于特定 Django app 的 `migrations` 目录中。永远不会有理由直接运行这个迁移脚本。它的存在只是为了让 Django 可以使用它作为更新数据库表的基础，或者在我们更新模型类时继承信息。 ``` (django-someHash) $ ./manage.py makemigrations - Migrations for 'todo': -   todo/migrations/0001_initial.py -     - Create model Task - ``` -这将查看 `INSTALLED_APPS` 中列出的每个应用程序，并检查这些应用程序中存在的模型。然后，它将检查相应的 `migrations` 目录中的迁移文件，并将它们与每个 `INSTALLED_APPS` 中的模型进行比较。如果模型升级已超出最新迁移所应存在的范围，则将创建一个继承自最新迁移文件的新迁移文件，它将自动命名，并且还会显示一条消息，说明自上次迁移以来发生了哪些更改。 +这将查找 `INSTALLED_APPS` 中列出的每个应用程序，并检查这些应用程序中存在的模型。然后，它将检查相应的 `migrations` 目录中的迁移文件，并将它们与每个 `INSTALLED_APPS` 中的模型进行比较。如果模型已经升级超出最新迁移所应存在的范围，则将创建一个继承自最新迁移文件的新迁移文件，它将自动命名，并且还会显示一条消息，说明自上次迁移以来发生了哪些更改。 -如果你上次处理 Django 项目已经有一段时间了，并且不记得模型是否与迁移同步，那么你无需担心。`makemigrations` 是一个幂等操作。无论你运行 `makemigrations` 一次还是 20 次，`migrations` 目录只有一个与当前模型配置的副本。还有更棒的，当我们运行 `./manage.py runserver` 时，Django 检测到我们的模型与迁移不同步，它会用彩色文本告诉我们以便我们可以做出适当的选择。 +如果你上次处理 Django 项目已经有一段时间了，并且不记得模型是否与迁移同步，那么你无需担心。`makemigrations` 是一个幂等操作。无论你运行 `makemigrations` 一次还是 20 次，`migrations` 目录只有一个与当前模型配置的副本。更棒的是，当我们运行 `./manage.py runserver` 时，Django 检测到我们的模型与迁移不同步，它会用彩色文本告诉我们以便我们可以做出适当的选择。 -下一个要点是至少让每个人访问一次：创建一个迁移文件不会立即影响我们的数据库。当我们运行 `makemigrations` 时，我们准备了 Django 项目来定义如何创建给定的表并最终查找。我们仍在将这些更改应用于数据库。这就是 `migrate` 命令的用途。 +下一个要点是至少让每个人访问一次：创建一个迁移文件不会立即影响我们的数据库。当我们运行 `makemigrations` 时，我们布置我们的 Django 项目定义了给定的表应该如何创建和最终查找。我们仍要将这些更改应用于数据库。这就是 `migrate` 命令的用途。 ``` (django-someHash) $ ./manage.py migrate - Operations to perform: - -  Apply all migrations: admin, auth, contenttypes, sessions, todo - + Apply all migrations: admin, auth, contenttypes, sessions, todo Running migrations: - -  Applying contenttypes.0001_initial... OK - -  Applying auth.0001_initial... OK - -  Applying admin.0001_initial... OK - -  Applying admin.0002_logentry_remove_auto_add... OK - -  Applying contenttypes.0002_remove_content_type_name... OK - -  Applying auth.0002_alter_permission_name_max_length... OK - -  Applying auth.0003_alter_user_email_max_length... OK - -  Applying auth.0004_alter_user_username_opts... OK - -  Applying auth.0005_alter_user_last_login_null... OK - -  Applying auth.0006_require_contenttypes_0002... OK - -  Applying auth.0007_alter_validators_add_error_messages... OK - -  Applying auth.0008_alter_user_username_max_length... OK - -  Applying auth.0009_alter_user_last_name_max_length... OK - -  Applying sessions.0001_initial... OK - -  Applying todo.0001_initial... OK - + Applying contenttypes.0001_initial... OK + Applying auth.0001_initial... OK + Applying admin.0001_initial... OK + Applying admin.0002_logentry_remove_auto_add... OK + Applying contenttypes.0002_remove_content_type_name... OK + Applying auth.0002_alter_permission_name_max_length... OK + Applying auth.0003_alter_user_email_max_length... OK + Applying auth.0004_alter_user_username_opts... OK + Applying auth.0005_alter_user_last_login_null... OK + Applying auth.0006_require_contenttypes_0002... OK + Applying auth.0007_alter_validators_add_error_messages... OK + Applying auth.0008_alter_user_username_max_length... OK + Applying auth.0009_alter_user_last_name_max_length... OK + Applying sessions.0001_initial... OK + Applying todo.0001_initial... OK ``` -当我们应用迁移时，Django 首先检查其他 `INSTALLED_APPS` 是否有要应用的迁移，它大致按照列出的顺序检查它们。我们希望我们的应用程序最后列出，因为我们希望确保，如果我们的模型依赖于任何 Django 的内置模型，我们所做的数据库更新不会受到依赖性问题的影响。 +当我们应用这些迁移时，Django 首先检查其他 `INSTALLED_APPS` 是否有需要应用的迁移，它大致按照列出的顺序检查它们。我们希望我们的应用程序最后列出，因为我们希望确保，如果我们的模型依赖于任何 Django 的内置模型，我们所做的数据库更新不会受到依赖性问题的影响。 -我们还有另一个要构建的模型：User 模型。但是，自从我们使用 Django 以来，游戏发生了一些变化。许多应用程序需要某种类型的用户模型，Django 的 `django.contrib.auth` 包构建了自己的用户模型供我们使用。如果它不是我们用户需要的身份验证令牌，我们可以继续使用它而不是重新发明轮子。 +我们还有另一个要构建的模型：`User` 模型。但是，因为我们正在使用 Django，事情有一些变化。许多应用程序需要某种类型的用户模型，Django 的 `django.contrib.auth` 包构建了自己的用户模型供我们使用。如果无需用户所需要的身份验证令牌，我们可以继续使用它而不是重新发明轮子。 但是，我们需要那个令牌。我们可以通过两种方式来处理这个问题。 - * 继承自 Django 的 `User` 对象，我们自己的对象通过添加 `token` 字段来扩展它 - * 创建一个与 Django 的 `User` 对象一对一关系的新对象，其唯一目的是持有一个令牌 +* 继承 Django 的 `User` 对象，我们自己的对象通过添加 `token` 字段来扩展它 +* 创建一个与 Django 的 `User` 对象一对一关系的新对象，其唯一目的是持有一个令牌 我习惯于建立对象关系，所以让我们选择第二种选择。我们称之为 `Owner`，因为它基本上具有与 `User` 类似的内涵，这就是我们想要的。 出于纯粹的懒惰，我们可以在 `todo/models.py` 中包含这个新的 `Owner` 对象，但是不要这样做。`Owner` 没有明确地与任务列表上的项目的创建或维护有关。从概念上讲，`Owner` 只是任务的所有者。甚至有时候我们想要扩展这个 `Owner` 以包含与任务完全无关的其他数据。 为了安全起见，让我们创建一个 `owner` 应用程序，其工作是容纳和处理这个 `Owner` 对象。 + ``` (django-someHash) $ ./manage.py startapp owner - ``` 不要忘记在 `settings.py` 文件中的 `INSTALLED_APPS` 中添加它。 ``` INSTALLED_APPS = [     'django.contrib.admin', -     'django.contrib.auth', -     'django.contrib.contenttypes', -     'django.contrib.sessions', -     'django.contrib.messages', -     'django.contrib.staticfiles', -     'rest_framework', -     'django_todo', -     'todo', -     'owner' ] - ``` 如果我们查看 Django 项目的根目录，我们现在有两个 Django 应用程序： + ``` (django-someHash) $ ls - Pipfile      Pipfile.lock django_todo  manage.py    owner        todo - ``` 在 `owner/models.py` 中，让我们构建这个 `Owner` 模型。如前所述，它与 Django 的内置 `User` 对象有一对一的关系。我们可以用 Django 的 `models.OneToOneField` 强制实现这种关系。 + ``` # owner/models.py - from django.db import models - from django.contrib.auth.models import User - import secrets - class Owner(models.Model): -     """The object that owns tasks.""" -     user = models.OneToOneField(User, on_delete=models.CASCADE) -     token = models.CharField(max_length=256) - -     def __init__(self, *args, **kwargs): -         """On construction, set token.""" -         self.token = secrets.token_urlsafe(64) -         super().__init__(*args, **kwargs) - ``` 这表示 `Owner` 对象对应到 `User` 对象，每个 `user` 实例有一个 `owner` 实例。`on_delete = models.CASCADE` 表示如果相应的 `User` 被删除，它所对应的 `Owner` 实例也将被删除。让我们运行 `makemigrations` 和 `migrate` 来将这个新模型放入到我们的数据库中。 + ``` (django-someHash) $ ./manage.py makemigrations - Migrations for 'owner': -   owner/migrations/0001_initial.py -     - Create model Owner - (django-someHash) $ ./manage.py migrate - Operations to perform: -   Apply all migrations: admin, auth, contenttypes, owner, sessions, todo - Running migrations: -   Applying owner.0001_initial... OK - ``` 现在我们的 `Owner` 需要拥有一些 `Task` 对象。它与上面看到的 `OneToOneField` 非常相似，只不过我们会在 `Task` 对象上贴一个 `ForeignKey` 字段指向 `Owner`。 ``` # todo/models.py - from django.db import models - from owner.models import Owner - class Task(models.Model): -     """Tasks for the To Do list.""" -     name = models.CharField(max_length=256) -     note = models.TextField(blank=True, null=True) -     creation_date = models.DateTimeField(auto_now_add=True) -     due_date = models.DateTimeField(blank=True, null=True) -     completed = models.BooleanField(default=False) -     owner = models.ForeignKey(Owner, on_delete=models.CASCADE) - ``` 每个待办事项列表任务只有一个可以拥有多个任务的所有者。删除该所有者后，他们拥有的任务都会随之删除。 @@ -642,120 +485,80 @@ class Task(models.Model): ``` (django-someHash) django $ ./manage.py makemigrations - You are trying to add a non-nullable field 'owner' to task without a default; we can't do that (the database needs something to populate existing rows). - Please select a fix: -  1) Provide a one-off default now (will be set on all existing rows with a null value for this column) -  2) Quit, and let me add a default in models.py - ``` 不好了！出现了问题！发生了什么？其实，当我们创建 `Owner` 对象并将其作为 `ForeignKey` 添加到 `Task` 时，要求每个 `Task` 都需要一个 `Owner`。但是，我们为 `Task` 对象进行的第一次迁移不包括该要求。因此，即使我们的数据库表中没有数据，Django 也会对我们的迁移进行预先检查，以确保它们兼容，而我们提议的这种新迁移不是。 有几种方法可以解决这类问题： - 1. 退出当前迁移并构建一个包含当前模型配置的新迁移 -  2. 将一个默认值添加到 `Task` 对象的 `owner` 字段 -  3. 允许任务为 `owner` 字段设置 `NULL` 值 - -方案 2 在这里没有多大意义。我们建议，任何创建的 `Task`，默认情况下都会对应到某个默认所有者，尽管不一定存在。（to 校正：后面这句发意义在哪里？既然它已经说了方案 2 没有意义） +1. 退出当前迁移并构建一个包含当前模型配置的新迁移 +2. 将一个默认值添加到 `Task` 对象的 `owner` 字段 +3. 允许任务为 `owner` 字段设置 `NULL` 值 +方案 2 在这里没有多大意义。我们建议，默认情况下，任何创建的 `Task` 都会对应到某个默认所有者，尽管默认所有者不一定存在。 方案 1 要求我们销毁和重建我们的迁移，而我们应该把它们留下。 -让我们考虑选项 3。在这种情况下，如果我们允许 `Task` 表为所有者提供空值，它不会很糟糕。从这一点开始创建的任何任务都必然拥有一个所有者。如果你的数据库表不是一个可重新架构的情况下，请删除迁移，删除表并重建迁移。 +让我们考虑选项 3。在这种情况下，如果我们允许 `Task` 表为所有者提供空值，它不会很糟糕。从这一点开始创建的任何任务都必然拥有一个所有者。如果你的数据库表并非不能接受重新架构，请删除该迁移、删除表并重建迁移。 + ``` # todo/models.py - from django.db import models - from owner.models import Owner - class Task(models.Model): -     """Tasks for the To Do list.""" -     name = models.CharField(max_length=256) -     note = models.TextField(blank=True, null=True) -     creation_date = models.DateTimeField(auto_now_add=True) -     due_date = models.DateTimeField(blank=True, null=True) -     completed = models.BooleanField(default=False) -     owner = models.ForeignKey(Owner, on_delete=models.CASCADE, null=True) - (django-someHash) $ ./manage.py makemigrations - Migrations for 'todo': -   todo/migrations/0002_task_owner.py -     - Add field owner to task - (django-someHash) $ ./manage.py migrate - Operations to perform: -   Apply all migrations: admin, auth, contenttypes, owner, sessions, todo - Running migrations: -   Applying todo.0002_task_owner... OK - ``` 酷！我们有模型了！欢迎使用 Django 声明对象的方式。 -为了更好地衡量，让我们确保无论何时制作 `User`，它都会自动与新的 `Owner` 对象对应。我们可以使用 Django 的 `signals` 系统来做到这一点。基本上，我们确切地表达了意图：“当我们得到一个新的 `User` 被构造的信号时，构造一个新的 `Owner` 并将新的 `User` 设置为 `Owner` 的 `user` 字段。”在实践中看起来像这样： +出于更好的权衡，让我们确保无论何时制作 `User`，它都会自动与新的 `Owner` 对象对应。我们可以使用 Django 的 `signals` 系统来做到这一点。基本上，我们确切地表达了意图：“当我们得到一个新的 `User` 被构造的信号时，构造一个新的 `Owner` 并将新的 `User` 设置为 `Owner` 的 `user` 字段。”在实践中看起来像这样： + ``` # owner/models.py - from django.contrib.auth.models import User - from django.db import models - from django.db.models.signals import post_save - from django.dispatch import receiver import secrets class Owner(models.Model): + """The object that owns tasks.""" + user = models.OneToOneField(User, on_delete=models.CASCADE) + token = models.CharField(max_length=256) -    """The object that owns tasks.""" - -    user = models.OneToOneField(User, on_delete=models.CASCADE) - -    token = models.CharField(max_length=256) - - -    def __init__(self, *args, **kwargs): - -        """On construction, set token.""" - -        self.token = secrets.token_urlsafe(64) - -        super().__init__(*args, **kwargs) + def __init__(self, *args, **kwargs): + """On construction, set token.""" + self.token = secrets.token_urlsafe(64) + super().__init__(*args, **kwargs) @receiver(post_save, sender=User) def link_user_to_owner(sender, **kwargs): - -    """If a new User is saved, create a corresponding Owner.""" - -    if kwargs['created']: - -        owner = Owner(user=kwargs['instance']) - -        owner.save() - + """If a new User is saved, create a corresponding Owner.""" + if kwargs['created']: + owner = Owner(user=kwargs['instance']) + owner.save() ``` 我们设置了一个函数，用于监听从 Django 中内置的 `User` 对象发送的信号。它正在等待 `User` 对象被保存之后的情况。这可以来自新的 `User` 或对现有 `User` 的更新。我们在监听功能中辨别出两种情况。 @@ -764,425 +567,307 @@ def link_user_to_owner(sender, **kwargs): 现在让我们谈谈我们将如何访问数据。 - ### 访问模型数据 -在 Flask, Pyramid 和 Tornado 框架中，我们通过对某些数据库会话运行查询来访问模型数据。也许它被附加到 `request` 对象，也许它是一个独立的 `session` 对象。无论如何，我们必须建立与数据库的实时连接并在该连接上进行查询。 +在 Flask、Pyramid 和 Tornado 框架中，我们通过对某些数据库会话运行查询来访问模型数据。也许它被附加到 `request` 对象，也许它是一个独立的 `session` 对象。无论如何，我们必须建立与数据库的实时连接并在该连接上进行查询。 这不是 Django 的工作方式。默认情况下，Django 不利用任何第三方对象关系映射（ORM）与数据库进行通信。相反，Django 允许模型类维护自己与数据库的对话。 从 `django.db.models.Model` 继承的每个模型类都会附加一个 `objects` 对象。这将取代我们熟悉的 `session` 或 `dbsession`。让我们打开 Django 给我们的特殊 shell，并研究这个 `objects` 对象是如何工作的。 + ``` (django-someHash) $ ./manage.py shell - Python 3.7.0 (default, Jun 29 2018, 20:13:13) [Clang 9.1.0 (clang-902.0.39.2)] on darwin Type "help", "copyright", "credits" or "license" for more information. (InteractiveConsole) - >>> - ``` -Django shell 与普通的 Python shell 不同，因为它知道我们正在构建的 Django 项目，可以轻松导入我们的模型，视图，设置等，而不必担心安装包。我们可以通过简单的 `import` 访问我们的模型。 +Django shell 与普通的 Python shell 不同，因为它知道我们正在构建的 Django 项目，可以轻松导入我们的模型、视图、设置等，而不必担心安装包。我们可以通过简单的 `import` 访问我们的模型。 + ``` >>> from owner.models import Owner - >>> Owner - - ``` 目前，我们没有 `Owner` 实例。我们可以通过 `Owner.objects.all()` 查询它们。 + ``` >>> Owner.objects.all() - - ``` -无论何时我们在 ` .objects` 对象上运行查询方法，我们都会得到 `QuerySet`。为了我们的目的，它实际上是一个 `list`，这个 `list` 向我们显示它是空的。让我们通过创建一个 `User` 来创建一个 `Owner`。 +无论何时我们在 ` .objects` 对象上运行查询方法，我们都会得到 `QuerySet`。为了我们的目的，它实际上是一个列表，这个列表向我们显示它是空的。让我们通过创建一个 `User` 来创建一个 `Owner`。 + ``` >>> from django.contrib.auth.models import User - >>> new_user = User(username='kenyattamurphy', email='kenyatta.murphy@gmail.com') - >>> new_user.set_password('wakandaforever') - >>> new_user.save() - ``` 如果我们现在查询所有的 `Owner`，我们应该会找到 Kenyatta。 + ``` >>> Owner.objects.all() - ]> - ``` 棒极了！我们得到了数据！ ### 序列化模型 -我们将在 “Hello World” 之外来回传递数据。因此，我们希望看到某种类似于 JSON 类型的输出，它可以很好地表示数据。获取该对象的数据并将其转换为 JSON 对象以通过 HTTP 提交是数据序列化的一种方式。在序列化数据时，我们正在获取我们目前拥有的数据并重新格式化以适应一些标准的，更易于理解的形式。 +我们将在 “Hello World” 之外来回传递数据。因此，我们希望看到某种类似于 JSON 类型的输出，它可以很好地表示数据。获取该对象的数据并将其转换为 JSON 对象以通过 HTTP 提交是数据序列化的一种方式。在序列化数据时，我们正在获取我们目前拥有的数据并重新格式化以适应一些标准的、更易于理解的形式。 -如果我用 Flask, Pyramid 和 Tornado 这样做，我会在每个模型上创建一个新方法，让用户可以直接调用 `to_json()`。`to_json()` 的唯一工作是返回一个 JSON 可序列化的（即数字，字符串，列表，词典）字典，其中包含我想要为所讨论的对象显示的任何字段。 +如果我用 Flask、Pyramid 和 Tornado 这样做，我会在每个模型上创建一个新方法，让用户可以直接调用 `to_json()`。`to_json()` 的唯一工作是返回一个 JSON 可序列化的（即数字、字符串、列表、字典）字典，其中包含我想要为所讨论的对象显示的任何字段。 对于 `Task` 对象，它可能看起来像这样： + ``` class Task(Base): + ...all the fields... -    ...all the fields... - -    def to_json(self): - -        """Convert task attributes to a JSON-serializable dict.""" - -        return { - -            'id': self.id, - -            'name': self.name, - -            'note': self.note, - -            'creation_date': self.creation_date.strftime('%m/%d/%Y %H:%M:%S'), - -            'due_date': self.due_date.strftime('%m/%d/%Y %H:%M:%S'), - -            'completed': self.completed, - -            'user': self.user_id - -        } - + def to_json(self): + """Convert task attributes to a JSON-serializable dict.""" + return { + 'id': self.id, + 'name': self.name, + 'note': self.note, + 'creation_date': self.creation_date.strftime('%m/%d/%Y %H:%M:%S'), + 'due_date': self.due_date.strftime('%m/%d/%Y %H:%M:%S'), + 'completed': self.completed, + 'user': self.user_id + } ``` 这不花哨，但它确实起到了作用。 -然而，Django REST Framework 为我们提供了一个对象，它不仅可以为我们这样做，还可以在我们想要创建新对象实例或更新现有实例时验证输入,它被称为 [ModelSerializer][15]。 +然而，Django REST 框架为我们提供了一个对象，它不仅可以为我们这样做，还可以在我们想要创建新对象实例或更新现有实例时验证输入，它被称为 [ModelSerializer][15]。 -Django REST Framework 的 `ModelSerializer` 是我们模型的有效文档。如果没有附加模型，它们就没有自己的生命（因为那里有 [Serializer][16] 类）。它们的主要工作是准确地表示我们的模型，并在我们的模型数据需要序列化并通过线路发送时，将其转换为 JSON。 +Django REST 框架的 `ModelSerializer` 是我们模型的有效文档。如果没有附加模型，它们就没有自己的生命（因为那里有 [Serializer][16] 类）。它们的主要工作是准确地表示我们的模型，并在我们的模型数据需要序列化并通过线路发送时，将其转换为 JSON。 + +Django REST 框架的 `ModelSerializer` 最适合简单对象。举个例子，假设我们在 `Task` 对象上没有 `ForeignKey`。我们可以为 `Task` 创建一个序列化器，它将根据需要将其字段值转换为 JSON，声明如下： -Django REST Framework 的 `ModelSerializer` 最适合简单对象。举个例子，假设我们在 `Task` 对象上没有 `ForeignKey`。我们可以为 `Task` 创建一个序列化器，它将根据需要将其字段值转换为 JSON，声明如下： ``` # todo/serializers.py - from rest_framework import serializers - from todo.models import Task - class TaskSerializer(serializers.ModelSerializer): -     """Serializer for the Task model.""" -     class Meta: -         model = Task -         fields = ('id', 'name', 'note', 'creation_date', 'due_date', 'completed') - ``` -在我们新的 `TaskSerializer` 中，我们创建了一个 `Meta` 类。`Meta` 的工作就是保存关于我们试图序列化的东西的信息（或元数据）。然后，我们会注意到要显示的特定字段。如果我们想要显示所有字段，我们可以简化过程并使用`'__all __'`。或者，我们可以使用 `exclude` 关键字而不是 `fields` 来告诉 Django REST Framework 我们想要除了少数几个字段以外的每个字段。我们可以拥有尽可能多的序列化器，所以也许我们想要一个用于一小部分字段而一个用于所有字段？在这里都可以。 +在我们新的 `TaskSerializer` 中，我们创建了一个 `Meta` 类。`Meta` 的工作就是保存关于我们试图序列化的东西的信息（或元数据）。然后，我们会注意到要显示的特定字段。如果我们想要显示所有字段，我们可以简化过程并使用 `__all __`。或者，我们可以使用 `exclude` 关键字而不是 `fields` 来告诉 Django REST 框架我们想要除了少数几个字段以外的每个字段。我们可以拥有尽可能多的序列化器，所以也许我们想要一个用于一小部分字段，而另一个用于所有字段？在这里都可以。 + +在我们的例子中，每个 `Task` 和它的所有者 `Owner` 之间都有一个关系，必须在这里反映出来。因此，我们需要借用 `serializers.PrimaryKeyRelatedField` 对象来指定每个 `Task` 都有一个 `Owner`，并且该关系是一对一的。它的所有者将从已有的全部所有者的集合中找到。我们通过对这些所有者进行查询并返回我们想要与此序列化程序关联的结果来获得该集合：`Owner.objects.all()`。我们还需要在字段列表中包含 `owner`，因为我们总是需要一个与 `Task` 相关联的 `Owner`。 -在我们的例子中，每个 `Task` 和它的所有者 `Owner` 之间都有一个关系，必须在这里反映出来。因此，我们需要借用 `serializers.PrimaryKeyRelatedField` 对象来指定每个 `Task` 都有一个 `Owner`，并且该关系是一对一的。它的 owner 将从存在的所有 owners 的集合中找到。我们通过对这些 owners 进行查询并返回我们想要与此序列化程序关联的结果来获得该集合：`Owner.objects.all()`。我们还需要在字段列表中包含 `owner`，因为我们总是需要一个与 `Task` 相关联的 `Owner`。 ``` # todo/serializers.py - from rest_framework import serializers - from todo.models import Task - from owner.models import Owner - class TaskSerializer(serializers.ModelSerializer): -     """Serializer for the Task model.""" -     owner = serializers.PrimaryKeyRelatedField(queryset=Owner.objects.all()) -     class Meta: -         model = Task -         fields = ('id', 'name', 'note', 'creation_date', 'due_date', 'completed', 'owner') - ``` 现在构建了这个序列化器，我们可以将它用于我们想要为我们的对象做的所有 CRUD 操作： - * 如果我们想要 `GET` 一个特定的 `Task` 的 JSON 类型版本，我们可以做 `TaskSerializer((some_task).data` - * 如果我们想接受带有适当数据的 `POST` 来创建一个新的 `Task`，我们可以使用 `TaskSerializer(data = new_data).save()` - - * 如果我们想用 `PUT` 更新一些现有数据，我们可以用 `TaskSerializer(existing_task, data = data).save()` +* 如果我们想要 `GET` 一个特定的 `Task` 的 JSON 类型版本，我们可以做 `TaskSerializer((some_task).data` +* 如果我们想接受带有适当数据的 `POST` 来创建一个新的 `Task`，我们可以使用 `TaskSerializer(data = new_data).save()` +* 如果我们想用 `PUT` 更新一些现有数据，我们可以用 `TaskSerializer(existing_task, data = data).save()` 我们没有包括 `delete`，因为我们不需要对 `delete` 操作做任何事情。如果你可以删除一个对象，只需使用 `object_instance.delete()`。 以下是一些序列化数据的示例： + ``` >>> from todo.models import Task - >>> from todo.serializers import TaskSerializer - >>> from owner.models import Owner - >>> from django.contrib.auth.models import User - >>> new_user = User(username='kenyatta', email='kenyatta@gmail.com') - >>> new_user.save_password('wakandaforever') - >>> new_user.save() # creating the User that builds the Owner - >>> kenyatta = Owner.objects.first() # 找到 kenyatta 的所有者 - >>> new_task = Task(name="Buy roast beef for the Sunday potluck", owner=kenyatta) - >>> new_task.save() - >>> TaskSerializer(new_task).data - {'id': 1, 'name': 'Go to the supermarket', 'note': None, 'creation_date': '2018-07-31T06:00:25.165013Z', 'due_date': None, 'completed': False, 'owner': 1} - ``` 使用 `ModelSerializer` 对象可以做更多的事情，我建议查看[文档][17]以获得更强大的功能。否则，这就是我们所需要的。现在是时候深入视图了。 ### 查看视图 -我们已经构建了模型和序列化器，现在我们需要为我们的应用程序设置视图和 URL。毕竟，对于没有视图的应用程序，我们无法做任何事情。我们已经看到了上面的 `HelloWorld` 视图的示例。然而，这总是一个人为的，概念验证的例子，并没有真正展示 Django REST Framework 的视图可以做些什么。让我们清除 `HelloWorld` 视图和 URL，这样我们就可以从我们的视图重新开始。 +我们已经构建了模型和序列化器，现在我们需要为我们的应用程序设置视图和 URL。毕竟，对于没有视图的应用程序，我们无法做任何事情。我们已经看到了上面的 `HelloWorld` 视图的示例。然而，这总是一个人为的、概念验证的例子，并没有真正展示 Django REST 框架的视图可以做些什么。让我们清除 `HelloWorld` 视图和 URL，这样我们就可以从我们的视图重新开始。 + +我们要构建的第一个视图是 `InfoView`。与之前的框架一样，我们只想打包并发送一个我们用到的路由的字典。视图本身可以存在于 `django_todo.views` 中，因为它与特定模型无关（因此在概念上不属于特定应用程序）。 -我们要构建的第一个视图是 `InfoView`。与之前的框架一样，我们只想打包并发送一个字典到正确的路由。视图本身可以存在于 `django_todo.views` 中，因为它与特定模型无关（因此在概念上不属于特定应用程序）。 ``` # django_todo/views.py - from rest_framework.response import JsonResponse - from rest_framework.views import APIView - class InfoView(APIView): - -    """List of routes for this API.""" - -    def get(self, request): - -        output = { - -            'info': 'GET /api/v1', - -            'register': 'POST /api/v1/accounts', - -            'single profile detail': 'GET /api/v1/accounts/', - -            'edit profile': 'PUT /api/v1/accounts/', - -            'delete profile': 'DELETE /api/v1/accounts/', - -            'login': 'POST /api/v1/accounts/login', - -            'logout': 'GET /api/v1/accounts/logout', - -            "user's tasks": 'GET /api/v1/accounts//tasks', - -            "create task": 'POST /api/v1/accounts//tasks', - -            "task detail": 'GET /api/v1/accounts//tasks/', - -            "task update": 'PUT /api/v1/accounts//tasks/', - -            "delete task": 'DELETE /api/v1/accounts//tasks/' - -        } - -        return JsonResponse(output) - + """List of routes for this API.""" + def get(self, request): + output = { + 'info': 'GET /api/v1', + 'register': 'POST /api/v1/accounts', + 'single profile detail': 'GET /api/v1/accounts/', + 'edit profile': 'PUT /api/v1/accounts/', + 'delete profile': 'DELETE /api/v1/accounts/', + 'login': 'POST /api/v1/accounts/login', + 'logout': 'GET /api/v1/accounts/logout', + "user's tasks": 'GET /api/v1/accounts//tasks', + "create task": 'POST /api/v1/accounts//tasks', + "task detail": 'GET /api/v1/accounts//tasks/', + "task update": 'PUT /api/v1/accounts//tasks/', + "delete task": 'DELETE /api/v1/accounts//tasks/' + } + return JsonResponse(output) ``` -这与我们在 Tornado 中所拥有的完全相同。让我们将它放置到合适的路由并继续前行。为了更好的测试，我们还将删除 `admin/` 路由，因为我们不会在这里使用 Django 管理后端。 +这与我们在 Tornado 中所拥有的完全相同。让我们将它放置到合适的路由并继续。为了更好的测试，我们还将删除 `admin/` 路由，因为我们不会在这里使用 Django 管理后端。 + ``` # in django_todo/urls.py - from django_todo.views import InfoView - from django.urls import path - urlpatterns = [ -     path('api/v1', InfoView.as_view(), name="info"), - ] - ``` #### 连接模型与视图 让我们弄清楚下一个 URL，它将是创建新的 `Task` 或列出用户现有任务的入口。这应该存在于 `todo` 应用程序的 `urls.py` 中，因为它必须专门处理 `Task `对象而不是整个项目的一部分。 + ``` # in todo/urls.py - from django.urls import path - from todo.views import TaskListView - urlpatterns = [ -     path('', TaskListView.as_view(), name="list_tasks") - ] - ``` 这个路由处理的是什么？我们根本没有指定特定用户或路径。由于会有一些路由需要基本路径 `/api/v1/accounts//tasks`，为什么我们只需写一次就能一次又一次地写它？ -Django 允许我们获取一整套 URL 并将它们导入 `django_todo/urls.py` 文件。然后，我们可以为这些导入的 URL 中的每一个提供相同的基本路径，只关心可变部分，你知道它们是不同的。 +Django 允许我们用一整套 URL 并将它们导入 `django_todo/urls.py` 文件。然后，我们可以为这些导入的 URL 中的每一个提供相同的基本路径，只关心可变部分，你知道它们是不同的。 + ``` # in django_todo/urls.py - from django.urls import include, path - from django_todo.views import InfoView - urlpatterns = [ -     path('api/v1', InfoView.as_view(), name="info"), -     path('api/v1/accounts//tasks', include('todo.urls')) - ] - ``` 现在，来自 `todo/urls.py` 的每个 URL 都将以路径 `api/v1/accounts//tasks` 为前缀。 让我们在 `todo/views.py` 中构建视图。 + ``` # todo/views.py - from django.shortcuts import get_object_or_404 - from rest_framework.response import JsonResponse - from rest_framework.views import APIView - from owner.models import Owner - from todo.models import Task - from todo.serializers import TaskSerializer class TaskListView(APIView): - -    def get(self, request, username, format=None): - -        """Get all of the tasks for a given user.""" - -        owner = get_object_or_404(Owner, user__username=username) - -        tasks = Task.objects.filter(owner=owner).all() - -        serialized = TaskSerializer(tasks, many=True) - -        return JsonResponse({ - -            'username': username, - -            'tasks': serialized.data - -        }) - + def get(self, request, username, format=None): + """Get all of the tasks for a given user.""" + owner = get_object_or_404(Owner, user__username=username) + tasks = Task.objects.filter(owner=owner).all() + serialized = TaskSerializer(tasks, many=True) + return JsonResponse({ + 'username': username, + 'tasks': serialized.data + }) ``` -这里有很多代码，让我们来看看吧。 +这里一点代码里面有许多要说明的，让我们来看看吧。 我们从与我们一直使用的 `APIView` 的继承开始，为我们的视图奠定基础。我们覆盖了之前覆盖的相同 `get` 方法，添加了一个参数，允许我们的视图从传入的请求中接收 `username`。 然后我们的 `get` 方法将使用 `username` 来获取与该用户关联的 `Owner`。这个 `get_object_or_404` 函数允许我们这样做，添加一些特殊的东西以方便使用。 -如果无法找到指定的用户，那么查找任务是没有意义的。实际上，我们想要返回 404 错误。`get_object_or_404` 根据我们传入的任何条件获取单个对象，并返回该对象或引发 [Http404 异常][18]。我们可以根据对象的属性设置该条件。`Owner` 对象都通过 `user` 属性附加到 `User`。但是，我们没有要搜索的 `User` 对象，我们只有一个 `username`。所以，当你寻找一个 `Owner` 时，我们对 `get_object_or_404` 说：通过指定 `user__username` 来检查附加到它的 `User` 是否具有我想要的 `username`。这是两个下划线。通过 QuerySet 过滤时，这两个下划线表示“此嵌套对象的属性”。这些属性可以根据需要进行深度嵌套。 +如果无法找到指定的用户，那么查找任务是没有意义的。实际上，我们想要返回 404 错误。`get_object_or_404` 根据我们传入的任何条件获取单个对象，并返回该对象或引发 [Http 404 异常][18]。我们可以根据对象的属性设置该条件。`Owner` 对象都通过 `user` 属性附加到 `User`。但是，我们没有要搜索的 `User` 对象，我们只有一个 `username`。所以，当你寻找一个 `Owner` 时，我们对 `get_object_or_404` 说：通过指定 `user__username`（这是两个下划线）来检查附加到它的 `User` 是否具有我想要的 `username`。通过 `QuerySet` 过滤时，这两个下划线表示 “此嵌套对象的属性”。这些属性可以根据需要进行深度嵌套。 -我们现在拥有与给定用户名相对应的 `Owner`。我们使用 `Owner` 来过滤所有任务，只用 `Task.objects.filter` 检索它拥有的任务。我们可以使用与 `get_object_or_404` 相同的嵌套属性模式来钻入连接到 `Tasks` 的 `Owner` 的 `User`(`tasks = Task.objects.filter(owner__user__username = username)).all()`)但是没有必要那么宽松。 +我们现在拥有与给定用户名相对应的 `Owner`。我们使用 `Owner` 来过滤所有任务，只用 `Task.objects.filter` 检索它拥有的任务。我们可以使用与 `get_object_or_404` 相同的嵌套属性模式来钻入连接到 `Tasks` 的 `Owner` 的 `User`（`tasks = Task.objects.filter(owner__user__username = username)).all()`），但是没有必要那么宽松。 -`Task.objects.filter(owner = owner).all()` 将为我们提供与我们的查询匹配的所有 `Task` 对象的`QuerySet`。大。然后，`TaskSerializer` 将获取 `QuerySet` 及其所有数据以及 `many = True` 标志，将其通知为项目集合而不是仅仅一个项目，并返回一系列序列化结果。实际上是一个词典列表。最后，我们使用 JSON 序列化数据和用于查询的用户名提供传出响应。 +`Task.objects.filter(owner = owner).all()` 将为我们提供与我们的查询匹配的所有 `Task` 对象的`QuerySet`。很棒。然后，`TaskSerializer` 将获取 `QuerySet` 及其所有数据以及 `many = True` 标志，以通知其为项目集合而不是仅仅一个项目，并返回一系列序列化结果。实际上是一个词典列表。最后，我们使用 JSON 序列化数据和用于查询的用户名提供传出响应。 #### 处理 POST 请求 `post` 方法看起来与我们之前看到的有些不同。 + ``` # still in todo/views.py - # ...other imports... - from rest_framework.parsers import JSONParser - from datetime import datetime - class TaskListView(APIView): + def get(self, request, username, format=None): + ... -    def get(self, request, username, format=None): + def post(self, request, username, format=None): + """Create a new Task.""" + owner = get_object_or_404(Owner, user__username=username) + data = JSONParser().parse(request) + data['owner'] = owner.id + if data['due_date']: + data['due_date'] = datetime.strptime(data['due_date'], '%d/%m/%Y %H:%M:%S') -        ... - - -    def post(self, request, username, format=None): - -        """Create a new Task.""" - -        owner = get_object_or_404(Owner, user__username=username) - -        data = JSONParser().parse(request) - -        data['owner'] = owner.id - -        if data['due_date']: - -            data['due_date'] = datetime.strptime(data['due_date'], '%d/%m/%Y %H:%M:%S') - - -        new_task = TaskSerializer(data=data) - -        if new_task.is_valid(): - -            new_task.save() - -            return JsonResponse({'msg': 'posted'}, status=201) - - -        return JsonResponse(new_task.errors, status=400) + new_task = TaskSerializer(data=data) + if new_task.is_valid(): + new_task.save() + return JsonResponse({'msg': 'posted'}, status=201) + return JsonResponse(new_task.errors, status=400) ``` 当我们从客户端接收数据时，我们使用 `JSONParser().parse(request)` 将其解析为字典。我们将所有者添加到数据中并格式化任务的 `due_date`（如果存在）。 -我们的 `TaskSerializer` 完成了繁重的任务。它首先接收传入的数据并将其转换为我们在模型上指定的字段。然后验证该数据以确保它适合指定的字段。如果附加到新 `Task` 的数据有效，它将使用该数据构造一个新的 `Task` 对象并将其提交给数据库。然后我们发回适当的“耶！我们做了一件新事!”响应。如果没有，我们收集 `TaskSerializer` 生成的错误，并将这些错误发送回客户端，并返回 `400 Bad Request` 状态代码。 +我们的 `TaskSerializer` 完成了繁重的任务。它首先接收传入的数据并将其转换为我们在模型上指定的字段。然后验证该数据以确保它适合指定的字段。如果附加到新 `Task` 的数据有效，它将使用该数据构造一个新的 `Task` 对象并将其提交给数据库。然后我们发回适当的“耶！我们做了一件新东西！”响应。如果没有，我们收集 `TaskSerializer` 生成的错误，并将这些错误发送回客户端，并返回 `400 Bad Request` 状态代码。 -如果我们要构建 `put` 视图来更新 `Task`，它看起来会非常相似。主要区别在于，当我们实例化 `TaskSerializer` 时，我们将传递旧对象和该对象的新数据，如 `TaskSerializer(existing_task，data = data)`。我们仍然会进行有效性检查并发回我们想要发回的回复。 +如果我们要构建 `put` 视图来更新 `Task`，它看起来会非常相似。主要区别在于，当我们实例化 `TaskSerializer` 时，我们将传递旧对象和该对象的新数据，如 `TaskSerializer(existing_task，data = data)`。我们仍然会进行有效性检查并发回我们想要发回的响应。 ### 总结 -Django 作为一个框架是高度可定制的，每个人都有自己的方式拼接 Django 项目。我在这里写出来的方式不一定是 Django 建立项目的确切方式。它只是 a) 我熟悉的方式，以及 b) 利用 Django 的管理系统。当你将概念分成他们自己的小筒仓时，Django 项目的复杂性会增加。这样做是为了让多个人更容易为整个项目做出贡献，而不会麻烦彼此。 +Django 作为一个框架是高度可定制的，每个人都有自己打造 Django 项目的方式。我在这里写出来的方式不一定是 Django 建立项目的确切方式。它只是 a) 我熟悉的方式，以及 b) 利用 Django 的管理系统。当你将概念切分到不同的小块时，Django 项目的复杂性会增加。这样做是为了让多个人更容易为整个项目做出贡献，而不会麻烦彼此。 -然而，作为 Django 项目的大量文件映射并不能使其更高效或自然地偏向于微服务架构。相反，它很容易成为一个令人困惑的巨石，这可能对你的项目仍然有用，它也可能使你的项目难以管理，尤其是随着项目的增长。 +然而，作为 Django 项目的大量文件映射并不能使其更高效或自然地偏向于微服务架构。相反，它很容易成为一个令人困惑的独石应用，这可能对你的项目仍然有用，它也可能使你的项目难以管理，尤其是随着项目的增长。 仔细考虑你的需求并使用合适的工具来完成正确的工作。对于像这样的简单项目，Django 可能不是合适的工具。 -Django 旨在处理多种模型，这些模型涵盖了不同的项目领域，但它们可能有一些共同点。这个项目是一个小型的双模型项目，有一些路由。如果我们要构建更多，我们只有七条路由，但仍然是相同的两个模型。这还不足以证明一个完整的 Django 项目。 +Django 旨在处理多种模型，这些模型涵盖了不同的项目领域，但它们可能有一些共同点。这个项目是一个小型的双模型项目，有一些路由。即便我们把它构建更复杂，也只有七条路由，而仍然只是相同的两个模型。这还不足以证明一个完整的 Django 项目。 -如果我们期望这个项目能够扩展，那将是一个很好的选择。这不是其中一个项目。这是选择一个点燃蜡烛的火焰喷射器。这是绝对的矫枉过正。（to 校正：这里有点迷糊） +如果我们期望这个项目能够拓展，那么将会是一个很好的选择。这不是那种项目。这就是使用火焰喷射器来点燃蜡烛，绝对是大材小用了。 -尽管如此，Web 框架仍然是一个 Web 框架，无论你使用哪个框架。它都可以接收请求并做出任何响应，因此你可以按照自己的意愿进行操作。只需要注意你选择的框架所带来的开销。 +尽管如此，Web 框架就是一个 Web 框架，无论你使用哪个框架。它都可以接收请求并做出任何响应，因此你可以按照自己的意愿进行操作。只需要注意你选择的框架所带来的开销。 就是这样！我们已经到了这个系列的最后！我希望这是一次启发性的冒险。当你在考虑如何构建你的下一个项目时，它将帮助你做出的不仅仅是最熟悉的选择。请务必阅读每个框架的文档，以扩展本系列中涉及的任何内容（因为它没有那么全面）。每个人都有一个广阔的世界。愉快地写代码吧！ @@ -1194,7 +879,7 @@ via: https://opensource.com/article/18/8/django-framework 作者：[Nicholas Hunt-Walker][a] 选题：[lujun9972](https://github.com/lujun9972) 译者：[MjSeven](https://github.com/MjSeven) -校对：[校对者ID](https://github.com/校对者ID) +校对：[Bestony](https://github.com/bestony), [wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20180820 How To Disable Ads In Terminal Welcome Message In Ubuntu Server.md b/published/201811/20180820 How To Disable Ads In Terminal Welcome Message In Ubuntu Server.md similarity index 100% rename from published/20180820 How To Disable Ads In Terminal Welcome Message In Ubuntu Server.md rename to published/201811/20180820 How To Disable Ads In Terminal Welcome Message In Ubuntu Server.md diff --git a/published/20180824 Joplin- Encrypted Open Source Note Taking And To-Do Application.md b/published/201811/20180824 Joplin- Encrypted Open Source Note Taking And To-Do Application.md similarity index 100% rename from published/20180824 Joplin- Encrypted Open Source Note Taking And To-Do Application.md rename to published/201811/20180824 Joplin- Encrypted Open Source Note Taking And To-Do Application.md diff --git a/published/20180827 Top 10 Raspberry Pi blogs to follow.md b/published/201811/20180827 Top 10 Raspberry Pi blogs to follow.md similarity index 100% rename from published/20180827 Top 10 Raspberry Pi blogs to follow.md rename to published/201811/20180827 Top 10 Raspberry Pi blogs to follow.md diff --git a/translated/tech/20180831 Test containers with Python and Conu.md b/published/201811/20180831 Test containers with Python and Conu.md similarity index 52% rename from translated/tech/20180831 Test containers with Python and Conu.md rename to published/201811/20180831 Test containers with Python and Conu.md index dbf9fa090b..286ebf116b 100644 --- a/translated/tech/20180831 Test containers with Python and Conu.md +++ b/published/201811/20180831 Test containers with Python and Conu.md @@ -3,11 +3,12 @@ ![](https://fedoramagazine.org/wp-content/uploads/2018/08/conu-816x345.jpg) -越来越多的开发人员使用容器开发和部署他们的应用。这意味着可以轻松地测试容器也变得很重要。[Conu][1] (container utilities 的简写) 是一个Python库，让你编写容器测试变得简单。本文向你介绍如何使用它测试容器。 +越来越多的开发人员使用容器开发和部署他们的应用。这意味着可以轻松地测试容器也变得很重要。[Conu][1] (container utilities 的简写) 是一个 Python 库，让你编写容器测试变得简单。本文向你介绍如何使用它测试容器。 ### 开始吧 -首先，你需要一个容器程序来测试。为此，以下命令创建一个包含一个容器 Dockerfile 和一个被容器伺服的 Flask 应用程序的文件夹。 +首先，你需要一个容器程序来测试。为此，以下命令创建一个包含一个容器的 Dockerfile 和一个被容器伺服的 Flask 应用程序的文件夹。 + ```bash $ mkdir container_test $ cd container_test @@ -15,22 +16,24 @@ $ touch Dockerfile $ touch app.py ``` -将以下代码复制到 app.py 文件中。这是惯常的基本 Flask 应用，它返回字符串“Hello Container World！”。 +将以下代码复制到 `app.py` 文件中。这是惯常的基本 Flask 应用，它返回字符串 “Hello Container World！”。 + ```python from flask import Flask app = Flask(__name__) @app.route('/') def hello_world(): - return 'Hello Container World!' + return 'Hello Container World!' if __name__ == '__main__': - app.run(debug=True,host='0.0.0.0') + app.run(debug=True,host='0.0.0.0') ``` ### 创建和构建测试容器 为了构建测试容器，将以下指令添加到 Dockerfile。 + ```dockerfile FROM registry.fedoraproject.org/fedora-minimal:latest RUN microdnf -y install python3-flask && microdnf clean all @@ -39,6 +42,7 @@ CMD ["python3", "/srv/app.py"] ``` 然后使用 Docker CLI 工具构建容器。 + ```bash $ sudo dnf -y install docker $ sudo systemctl start docker @@ -48,6 +52,7 @@ $ sudo docker build . -t flaskapp_container 提示：只有在系统上未安装 Docker 时才需要前两个命令。 构建之后使用以下命令运行容器。 + ```bash $ sudo docker run -p 5000:5000 --rm flaskapp_container * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit) @@ -56,17 +61,19 @@ $ sudo docker run -p 5000:5000 --rm flaskapp_container * Debugger PIN: 473-505-51 ``` -最后，使用 curl 检查 Flask 应用程序是否在容器内正确运行： +最后，使用 `curl` 检查 Flask 应用程序是否在容器内正确运行： + ```bash $ curl http://127.0.0.1:5000 Hello Container World! ``` -现在，flaskapp_container 正在运行并准备好进行测试，你可以使用 Ctrl+C 将其停止。 +现在，flaskapp_container 正在运行并准备好进行测试，你可以使用 `Ctrl+C` 将其停止。 ### 创建测试脚本 -在编写测试脚本之前，必须安装 conu。在先前创建的 container_test 目录中，运行以下命令。 +在编写测试脚本之前，必须安装 `conu`。在先前创建的 `container_test` 目录中，运行以下命令。 + ```bash $ python3 -m venv .venv $ source .venv/bin/activate @@ -75,48 +82,48 @@ $ source .venv/bin/activate $ touch test_container.py ``` -然后将以下脚本复制并保存在 test_container.py 文件中。 +然后将以下脚本复制并保存在 `test_container.py` 文件中。 + ```python import conu PORT = 5000 with conu.DockerBackend() as backend: - image = backend.ImageClass("flaskapp_container") - options = ["-p", "5000:5000"] - container = image.run_via_binary(additional_opts=options) + image = backend.ImageClass("flaskapp_container") + options = ["-p", "5000:5000"] + container = image.run_via_binary(additional_opts=options) + + try: + # Check that the container is running and wait for the flask application to start. + assert container.is_running() + container.wait_for_port(PORT) + + # Run a GET request on / port 5000. + http_response = container.http_request(path="/", port=PORT) + + # Check the response status code is 200 + assert http_response.ok + + # Get the response content + response_content = http_response.content.decode("utf-8") - try: - # Check that the container is running and wait for the flask application to start. - assert container.is_running() - container.wait_for_port(PORT) + # Check that the "Hello Container World!" string is served. + assert "Hello Container World!" in response_content - # Run a GET request on / port 5000. - http_response = container.http_request(path="/", port=PORT) - - # Check the response status code is 200 - assert http_response.ok - - # Get the response content - response_content = http_response.content.decode("utf-8") - - # Check that the "Hello Container World!" string is served. - assert "Hello Container World!" in response_content - - # Get the logs from the container - logs = [line for line in container.logs()] - # Check the the Flask application saw the GET request. - assert b'"GET / HTTP/1.1" 200 -' in logs[-1] - - finally: - container.stop() - container.delete() + # Get the logs from the container + logs = [line for line in container.logs()] + # Check the the Flask application saw the GET request. + assert b'"GET / HTTP/1.1" 200 -' in logs[-1] + finally: + container.stop() + container.delete() ``` #### 测试设置 -这个脚本首先设置 conu 使用 Docker 作为后端来运行容器。然后它设置容器镜像以使用你在本教程第一部分中构建的 flaskapp_container。 +这个脚本首先设置 `conu` 使用 Docker 作为后端来运行容器。然后它设置容器镜像以使用你在本教程第一部分中构建的 flaskapp_container。 下一步是配置运行容器所需的选项。在此示例中，Flask 应用在端口5000上提供内容。于是你需要暴露此端口并将其映射到主机上的同一端口。 @@ -124,13 +131,13 @@ with conu.DockerBackend() as backend: #### 测试方法 -在测试容器之前，检查容器是否正在运行并准备就绪。示范脚本使用 container.is_running 和 container.wait_for_port。这些方法可确保容器正在运行，并且服务在预设端口上可用。 +在测试容器之前，检查容器是否正在运行并准备就绪。示范脚本使用 `container.is_running` 和 `container.wait_for_port`。这些方法可确保容器正在运行，并且服务在预设端口上可用。 -container.http_request 是 [request][2] 库的包装器，可以方便地在测试期间发送 HTTP 请求。这个方法返回[requests.Responseobject][3]，因此可以轻松地访问响应的内容以进行测试。 +`container.http_request` 是 [request][2] 库的包装器，可以方便地在测试期间发送 HTTP 请求。这个方法返回[requests.Responseobject][3]，因此可以轻松地访问响应的内容以进行测试。 -Conu 还可以访问容器日志。又一次，这在测试期间非常有用。在上面的示例中，container.logs 方法返回容器日志。你可以使用它们断言打印了特定日志，或者，例如在测试期间没有异常被引发。 +`conu` 还可以访问容器日志。又一次，这在测试期间非常有用。在上面的示例中，`container.logs` 方法返回容器日志。你可以使用它们断言打印了特定日志，或者，例如在测试期间没有异常被引发。 -Conu 提供了许多与容器接合的有用方法。[文档][4]中提供了完整的 API 列表。你还可以参考 [GitHub][5] 上提供的示例。 +`conu` 提供了许多与容器接合的有用方法。[文档][4]中提供了完整的 API 列表。你还可以参考 [GitHub][5] 上提供的示例。 运行本教程所需的所有代码和文件也可以在 [GitHub][6] 上获得。 对于想要进一步采用这个例子的读者，你可以看看使用 [pytest][7] 来运行测试并构建一个容器测试套件。 @@ -141,7 +148,7 @@ via: https://fedoramagazine.org/test-containers-python-conu/ 作者：[Clément Verna][a] 选题：[lujun9972](https://github.com/lujun9972) 译者：[GraveAccent](https://github.com/GraveAccent) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20180901 Flameshot - A Simple, Yet Powerful Feature-rich Screenshot Tool.md b/published/201811/20180901 Flameshot - A Simple, Yet Powerful Feature-rich Screenshot Tool.md similarity index 100% rename from published/20180901 Flameshot - A Simple, Yet Powerful Feature-rich Screenshot Tool.md rename to published/201811/20180901 Flameshot - A Simple, Yet Powerful Feature-rich Screenshot Tool.md diff --git a/published/20180903 A Cross-platform High-quality GIF Encoder.md b/published/201811/20180903 A Cross-platform High-quality GIF Encoder.md similarity index 100% rename from published/20180903 A Cross-platform High-quality GIF Encoder.md rename to published/201811/20180903 A Cross-platform High-quality GIF Encoder.md diff --git a/published/20180905 How To Run MS-DOS Games And Programs In Linux.md b/published/201811/20180905 How To Run MS-DOS Games And Programs In Linux.md similarity index 100% rename from published/20180905 How To Run MS-DOS Games And Programs In Linux.md rename to published/201811/20180905 How To Run MS-DOS Games And Programs In Linux.md diff --git a/published/20180907 6 open source tools for writing a book.md b/published/201811/20180907 6 open source tools for writing a book.md similarity index 100% rename from published/20180907 6 open source tools for writing a book.md rename to published/201811/20180907 6 open source tools for writing a book.md diff --git a/published/201811/20180907 6.828 lab tools guide.md b/published/201811/20180907 6.828 lab tools guide.md new file mode 100644 index 0000000000..936ce535f8 --- /dev/null +++ b/published/201811/20180907 6.828 lab tools guide.md @@ -0,0 +1,222 @@ +Caffeinated 6.828：实验工具指南 +====== + +熟悉你的环境对高效率的开发和调试来说是至关重要的。本文将为你简单概述一下 JOS 环境和非常有用的 GDB 和 QEMU 命令。话虽如此，但你仍然应该去阅读 GDB 和 QEMU 手册，来理解这些强大的工具如何使用。 + +### 调试小贴士 + +#### 内核 + +GDB 是你的朋友。使用 `qemu-gdb target`（或它的变体 `qemu-gdb-nox`）使 QEMU 等待 GDB 去绑定。下面在调试内核时用到的一些命令，可以去查看 GDB 的资料。 + +如果你遭遇意外的中断、异常、或三重故障，你可以使用 `-d` 参数要求 QEMU 去产生一个详细的中断日志。 + +调试虚拟内存问题时，尝试 QEMU 的监视命令 `info mem`（提供内存高级概述）或 `info pg`（提供更多细节内容）。注意，这些命令仅显示**当前**页表。 + +（在实验 4 以后）去调试多个 CPU 时，使用 GDB 的线程相关命令，比如 `thread` 和 `info threads`。 + +#### 用户环境（在实验 3 以后） + +GDB 也可以去调试用户环境，但是有些事情需要注意，因为 GDB 无法区分开多个用户环境或区分开用户环境与内核环境。 + +你可以使用 `make run-name`（或编辑 `kern/init.c` 目录）来指定 JOS 启动的用户环境，为使 QEMU 等待 GDB 去绑定，使用 `run-name-gdb` 的变体。 + +你可以符号化调试用户代码，就像调试内核代码一样，但是你要告诉 GDB，哪个符号表用到符号文件命令上，因为它一次仅能够使用一个符号表。提供的 `.gdbinit` 用于加载内核符号表 `obj/kern/kernel`。对于一个用户环境，这个符号表在它的 ELF 二进制文件中，因此你可以使用 `symbol-file obj/user/name` 去加载它。不要从任何 `.o` 文件中加载符号，因为它们不会被链接器迁移进去（库是静态链接进 JOS 用户二进制文件中的，因此这些符号已经包含在每个用户二进制文件中了）。确保你得到了正确的用户二进制文件；在不同的二进制文件中，库函数被链接为不同的 EIP，而 GDB 并不知道更多的内容！ + +（在实验 4 以后）因为 GDB 绑定了整个虚拟机，所以它可以将时钟中断看作为一种控制转移。这使得从底层上不可能实现步进用户代码，因为一个时钟中断无形中保证了片刻之后虚拟机可以再次运行。因此可以使用 `stepi` 命令，因为它阻止了中断，但它仅可以步进一个汇编指令。断点一般来说可以正常工作，但要注意，因为你可能在不同的环境（完全不同的一个二进制文件）上遇到同一个 EIP。 + +### 参考 + +#### JOS makefile + +JOS 的 GNUmakefile 包含了在各种方式中运行的 JOS 的许多假目标。所有这些目标都配置 QEMU 去监听 GDB 连接（`*-gdb` 目标也等待这个连接）。要在运行中的 QEMU 上启动它，只需要在你的实验目录中简单地运行 `gdb ` 即可。我们提供了一个 `.gdbinit` 文件，它可以在 QEMU 中自动指向到 GDB、加载内核符号文件、以及在 16 位和 32 位模式之间切换。退出 GDB 将关闭 QEMU。 + + * `make qemu` + + 在一个新窗口中构建所有的东西并使用 VGA 控制台和你的终端中的串行控制台启动 QEMU。想退出时，既可以关闭 VGA 窗口，也可以在你的终端中按 `Ctrl-c` 或 `Ctrl-a x`。 + * `make qemu-nox` + + 和 `make qemu` 一样，但仅使用串行控制台来运行。想退出时，按下 `Ctrl-a x`。这种方式在通过 SSH 拨号连接到 Athena 上时非常有用，因为 VGA 窗口会占用许多带宽。 + * `make qemu-gdb` + + 和 `make qemu` 一样，但它与任意时间被动接受 GDB 不同，而是暂停第一个机器指令并等待一个 GDB 连接。 + * `make qemu-nox-gdb` + + 它是 `qemu-nox` 和 `qemu-gdb` 目标的组合。 + * `make run-nam` + + （在实验 3 以后）运行用户程序 _name_。例如，`make run-hello` 运行 `user/hello.c`。 + * `make run-name-nox`,`run-name-gdb`, `run-name-gdb-nox` + + （在实验 3 以后）与 `qemu` 目标变量对应的 `run-name` 的变体。 + +makefile 也接受几个非常有用的变量： + + * `make V=1 …` + + 详细模式。输出正在运行的每个命令，包括参数。 + * `make V=1 grade` + + 在评级测试失败后停止，并将 QEMU 的输出放入 `jos.out` 文件中以备检查。 + * `make QEMUEXTRA=' _args_ ' …` + + 指定传递给 QEMU 的额外参数。 + +#### JOS obj/ + +在构建 JOS 时，makefile 也产生一些额外的输出文件，这些文件在调试时非常有用： + + * `obj/boot/boot.asm`、`obj/kern/kernel.asm`、`obj/user/hello.asm`、等等。 + + 引导加载器、内核、和用户程序的汇编代码列表。 + * `obj/kern/kernel.sym`、`obj/user/hello.sym`、等等。 + + 内核和用户程序的符号表。 + * `obj/boot/boot.out`、`obj/kern/kernel`、`obj/user/hello`、等等。 + + 内核和用户程序链接的 ELF 镜像。它们包含了 GDB 用到的符号信息。 + +#### GDB + +完整的 GDB 命令指南请查看 [GDB 手册][1]。下面是一些在 6.828 课程中非常有用的命令，它们中的一些在操作系统开发之外的领域几乎用不到。 + + * `Ctrl-c` + + 在当前指令处停止机器并打断进入到 GDB。如果 QEMU 有多个虚拟的 CPU，所有的 CPU 都会停止。 + * `c`（或 `continue`） + + 继续运行，直到下一个断点或 `Ctrl-c`。 + * `si`（或 `stepi`） + + 运行一个机器指令。 + * `b function` 或 `b file:line`（或 `breakpoint`） + + 在给定的函数或行上设置一个断点。 + * `b * addr`（或 `breakpoint`） + + 在 EIP 的 addr 处设置一个断点。 + * `set print pretty` + + 启用数组和结构的美化输出。 + * `info registers` + + 输出通用寄存器 `eip`、`eflags`、和段选择器。更多更全的机器寄存器状态转储，查看 QEMU 自己的 `info registers` 命令。 + * `x/ N x addr` + + 以十六进制显示虚拟地址 addr 处开始的 N 个词的转储。如果 N 省略，默认为 1。addr 可以是任何表达式。 + * `x/ N i addr` + + 显示从 addr 处开始的 N 个汇编指令。使用 `$eip` 作为 addr 将显示当前指令指针寄存器中的指令。 + * `symbol-file file` + + （在实验 3 以后）切换到符号文件 file 上。当 GDB 绑定到 QEMU 后，它并不是虚拟机中进程边界内的一部分，因此我们要去告诉它去使用哪个符号。默认情况下，我们配置 GDB 去使用内核符号文件 `obj/kern/kernel`。如果机器正在运行用户代码，比如是 `hello.c`，你就需要使用 `symbol-file obj/user/hello` 去切换到 hello 的符号文件。 + +QEMU 将每个虚拟 CPU 表示为 GDB 中的一个线程，因此你可以使用 GDB 中所有的线程相关的命令去查看或维护 QEMU 的虚拟 CPU。 + + * `thread n` + + GDB 在一个时刻只关注于一个线程（即：CPU）。这个命令将关注的线程切换到 n，n 是从 0 开始编号的。 + * `info threads` + + 列出所有的线程（即：CPU），包括它们的状态（活动还是停止）和它们在什么函数中。 + + +#### QEMU + +QEMU 包含一个内置的监视器，它能够有效地检查和修改机器状态。想进入到监视器中，在运行 QEMU 的终端中按入 `Ctrl-a c` 即可。再次按下 `Ctrl-a c` 将切换回串行控制台。 + +监视器命令的完整参考资料，请查看 [QEMU 手册][2]。下面是 6.828 课程中用到的一些有用的命令： + + * `xp/ N x paddr` + + 显示从物理地址 paddr 处开始的 N 个词的十六进制转储。如果 N 省略，默认为 1。这是 GDB 的 `x` 命令模拟的物理内存。 + * `info registers` + + 显示机器内部寄存器状态的一个完整转储。实践中，对于段选择器，这将包含机器的 _隐藏_ 段状态和局部、全局、和中断描述符表加任务状态寄存器。隐藏状态是在加载段选择器后，虚拟的 CPU 从 GDT/LDT 中读取的信息。下面是实验 1 中 JOS 内核处于运行中时的 CS 信息和每个字段的含义： + + ```c + CS =0008 10000000 ffffffff 10cf9a00 DPL=0 CS32 [-R-] + ``` + + * `CS =0008` + + 代码选择器可见部分。我们使用段 0x8。这也告诉我们参考全局描述符表（0x8&4=0），并且我们的 CPL（当前权限级别）是 0x8&3=0。 + * `10000000` + + 这是段基址。线性地址 = 逻辑地址 + 0x10000000。 + * `ffffffff` + + 这是段限制。访问线性地址 0xffffffff 以上将返回段违规异常。 + * `10cf9a00` + + 段的原始标志，QEMU 将在接下来的几个字段中解码这些对我们有用的标志。 + * `DPL=0` + + 段的权限级别。一旦代码以权限 0 运行，它将就能够加载这个段。 + * `CS32` + + 这是一个 32 位代码段。对于数据段（不要与 DS 寄存器混淆了），另外的值还包括 `DS`，而对于本地描述符表是 `LDT`。 + * `[-R-]` + + 这个段是只读的。 + + * `info mem` + + （在实验 2 以后）显示映射的虚拟内存和权限。比如： + + ``` + ef7c0000-ef800000 00040000 urw + efbf8000-efc00000 00008000 -rw + ``` + + 这告诉我们从 0xef7c0000 到 0xef800000 的 0x00040000 字节的内存被映射为读取/写入/用户可访问，而映射在 0xefbf8000 到 0xefc00000 之间的内存权限是读取/写入，但是仅限于内核可访问。 + + * `info pg` + + （在实验 2 以后）显示当前页表结构。它的输出类似于 `info mem`，但与页目录条目和页表条目是有区别的，并且为每个条目给了单独的权限。重复的 PTE 和整个页表被折叠为一个单行。例如： + + ``` +VPN range Entry Flags Physical page +[00000-003ff] PDE[000] -------UWP + [00200-00233] PTE[200-233] -------U-P 00380 0037e 0037d 0037c 0037b 0037a .. +[00800-00bff] PDE[002] ----A--UWP + [00800-00801] PTE[000-001] ----A--U-P 0034b 00349 + [00802-00802] PTE[002] -------U-P 00348 + ``` + + 这里各自显示了两个页目录条目、虚拟地址范围 0x00000000 到 0x003fffff 以及 0x00800000 到 0x00bfffff。 所有的 PDE 都存在于内存中、可写入、并且用户可访问，而第二个 PDE 也是可访问的。这些页表中的第二个映射了三个页、虚拟地址范围 0x00800000 到 0x00802fff，其中前两个页是存在于内存中的、可写入、并且用户可访问的，而第三个仅存在于内存中，并且用户可访问。这些 PTE 的第一个条目映射在物理页 0x34b 处。 + +QEMU 也有一些非常有用的命令行参数，使用 `QEMUEXTRA` 变量可以将参数传递给 JOS 的 makefile。 + + * `make QEMUEXTRA='-d int' ...` + + 记录所有的中断和一个完整的寄存器转储到 `qemu.log` 文件中。你可以忽略前两个日志条目、“SMM: enter” 和 “SMM: after RMS”，因为这些是在进入引导加载器之前生成的。在这之后的日志条目看起来像下面这样： + + ``` + 4: v=30 e=0000 i=1 cpl=3 IP=001b:00800e2e pc=00800e2e SP=0023:eebfdf28 EAX=00000005 +EAX=00000005 EBX=00001002 ECX=00200000 EDX=00000000 +ESI=00000805 EDI=00200000 EBP=eebfdf60 ESP=eebfdf28 +... +``` + + 第一行描述了中断。`4:` 只是一个日志记录计数器。`v` 提供了十六进程的向量号。`e` 提供了错误代码。`i=1` 表示它是由一个 `int` 指令（相对一个硬件产生的中断而言）产生的。剩下的行的意思很明显。对于一个寄存器转储而言，接下来看到的就是寄存器信息。 + + 注意：如果你运行的是一个 0.15 版本之前的 QEMU，日志将写入到 `/tmp` 目录，而不是当前目录下。 + + + +-------------------------------------------------------------------------------- + +via: https://pdos.csail.mit.edu/6.828/2018/labguide.html + +作者：[csail.mit][a] +选题：[lujun9972][b] +译者：[qhwdw](https://github.com/qhwdw) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://pdos.csail.mit.edu +[b]: https://github.com/lujun9972 +[1]: http://sourceware.org/gdb/current/onlinedocs/gdb/ +[2]: http://wiki.qemu.org/download/qemu-doc.html#pcsys_005fmonitor diff --git a/published/20180911 Tools Used in 6.828.md b/published/201811/20180911 Tools Used in 6.828.md similarity index 100% rename from published/20180911 Tools Used in 6.828.md rename to published/201811/20180911 Tools Used in 6.828.md diff --git a/published/20180914 Convert files at the command line with Pandoc.md b/published/201811/20180914 Convert files at the command line with Pandoc.md similarity index 100% rename from published/20180914 Convert files at the command line with Pandoc.md rename to published/201811/20180914 Convert files at the command line with Pandoc.md diff --git a/translated/talk/20180921 IssueHunt- A New Bounty Hunting Platform for Open Source Software.md b/published/201811/20180921 IssueHunt- A New Bounty Hunting Platform for Open Source Software.md similarity index 68% rename from translated/talk/20180921 IssueHunt- A New Bounty Hunting Platform for Open Source Software.md rename to published/201811/20180921 IssueHunt- A New Bounty Hunting Platform for Open Source Software.md index 3d4c9a2702..d04ccd34c7 100644 --- a/translated/talk/20180921 IssueHunt- A New Bounty Hunting Platform for Open Source Software.md +++ b/published/201811/20180921 IssueHunt- A New Bounty Hunting Platform for Open Source Software.md @@ -1,34 +1,35 @@ IssueHunt：一个新的开源软件打赏平台 ====== -许多开源开发者和公司都在努力解决的问题之一就是资金问题。社区中有一种假想，甚至是期望，必须免费提供自由和开源软件。但即使是 FOSS 也需要资金来继续开发。如果我们不建立让软件持续开发的系统，我们怎能期待更高质量的软件？ -我们已经写了一篇关于[开源资金平台][1]的文章来试图解决这个缺点，截至今年 7 月，市场上出现了一个新的竞争者，旨在帮助填补这个空白：[IssueHunt][2] 。 +![IssueHunt][4] + +许多开源开发者和公司都在努力解决的问题之一就是资金问题。社区中有一种假想，甚至是期望，必须免费提供自由开源软件（FOSS）。但即使是 FOSS 也需要资金来继续开发。如果我们不建立让软件持续开发的系统，我们怎能期待更高质量的软件？ + +我们已经写了一篇关于[开源资金平台][1]的文章来试图解决这个缺点，截至今年 7 月，市场上出现了一个新的竞争者，旨在帮助填补这个空白：[IssueHunt][2]。 ### IssueHunt: 开源软件打赏平台 ![IssueHunt website][3] -IssueHunt 提供了一种服务，支付自由开发者对开源代码的贡献。它通过所谓的赏金来实现：给予解决特定问题的任何人财务奖励。这些奖励的资金来自任何愿意捐赠以修复任何特定 bug 或添加功能的人。 +IssueHunt 提供了一种服务，对自由开发者的开源代码贡献进行支付。它通过所谓的赏金来实现：给予解决特定问题的任何人财务奖励。这些奖励的资金来自任何愿意捐赠以修复任何特定 bug 或添加功能的人。 如果你想修复的某个开源软件存在问题，你可以根据自己选择的方式提供奖励金额。 想要自己的产品被争抢解决么？在 IssueHunt 上向任何解决问题的人提供奖金就好了。就这么简单。 -如果你是程序员，则可以浏览未解决的问题。解决这个问题（如果你可以的话），在 GitHub 存储库上提交 pull request，如果你的 pull request 被合并，那么你就会得到了钱。 +如果你是程序员，则可以浏览未解决的问题。解决这个问题（如果你可以的话），在 GitHub 存储库上提交拉取请求，如果你的拉取请求被合并，那么你就会得到了钱。 #### IssueHunt 最初是 Boostnote 的内部项目 -![IssueHunt][4] - 当笔记应用 [Boostnote][5] 背后的开发人员联系社区为他们的产品做出贡献时，该产品出现了。 在使用 IssueHunt 的前两年，Boostnote 通过数百名贡献者和压倒性的捐款收到了超过 8,400 个 Github star。 该产品非常成功，团队决定将其开放给社区的其他成员。 -今天，[列表中在使用这个服务的项目][6]提供了数千美元的赏金。 +如今，[列表中在使用这个服务的项目][6]提供了数千美元的赏金。 -Boostnote 号称有 [$2,800 的总赏金] [7]，而 Settings Sync，以前称为 Visual Studio Code Settings Sync，提供了[超过 $1,600 的赏金][8]。 +Boostnote 号称有 [$2,800 的总赏金][7]，而 Settings Sync，以前称为 Visual Studio Code Settings Sync，提供了[超过 $1,600 的赏金][8]。 还有其他服务提供类似于 IssueHunt 在此提供的内容。也许最引人注目的是 [Bountysource][9]，它提供与 IssueHunt 类似的赏金服务，同时还提供类似于 [Librepay][10] 的订阅支付处理。 @@ -36,7 +37,7 @@ Boostnote 号称有 [$2,800 的总赏金] [7]，而 Settings Sync，以前称为 在撰写本文时，IssueHunt 还处于起步阶段，但我非常高兴看到这个项目在这些年里的成果。 -我不了解你，但我非常乐意为 FOSS 付款。如果产品质量高，并为我的生活增添价值，那么我很乐意向开发者支付产品费用。特别是 FOSS 的开发者正在创造尊重我自由的产品。 +我不知道你会怎么看，但我非常乐意为 FOSS 付款。如果产品质量高，并为我的生活增添价值，那么我很乐意向开发者支付产品费用。特别是 FOSS 的开发者正在创造尊重我自由的产品。 话虽如此，我一定会关注 IssueHunt 的继续前进，我可以用自己的钱或者在需要贡献的地方传播这个它来支持社区。 @@ -49,15 +50,15 @@ via: https://itsfoss.com/issuehunt/ 作者：[Phillip Prado][a] 选题：[lujun9972](https://github.com/lujun9972) 译者：[geekpi](https://github.com/geekpi) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 [a]: https://itsfoss.com/author/phillip/ [1]: https://itsfoss.com/open-source-funding-platforms/ [2]: https://issuehunt.io -[3]: https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/09/issuehunt-website.png -[4]: https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/09/issuehunt.jpg +[3]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/09/issuehunt-website.png?w=799&ssl=1 +[4]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/09/issuehunt.jpg?w=800&ssl=1 [5]: https://itsfoss.com/boostnote-linux-review/ [6]: https://issuehunt.io/repos [7]: https://issuehunt.io/repos/53266139 diff --git a/published/20180928 Using Grails with jQuery and DataTables.md b/published/201811/20180928 Using Grails with jQuery and DataTables.md similarity index 100% rename from published/20180928 Using Grails with jQuery and DataTables.md rename to published/201811/20180928 Using Grails with jQuery and DataTables.md diff --git a/published/20180928 What containers can teach us about DevOps.md b/published/201811/20180928 What containers can teach us about DevOps.md similarity index 100% rename from published/20180928 What containers can teach us about DevOps.md rename to published/201811/20180928 What containers can teach us about DevOps.md diff --git a/translated/tech/20181001 Turn your book into a website and an ePub using Pandoc.md b/published/201811/20181001 Turn your book into a website and an ePub using Pandoc.md similarity index 73% rename from translated/tech/20181001 Turn your book into a website and an ePub using Pandoc.md rename to published/201811/20181001 Turn your book into a website and an ePub using Pandoc.md index 54a92afd88..734ac021cb 100644 --- a/translated/tech/20181001 Turn your book into a website and an ePub using Pandoc.md +++ b/published/201811/20181001 Turn your book into a website and an ePub using Pandoc.md @@ -1,13 +1,13 @@ 使用 Pandoc 将你的书转换成网页和电子书 ====== -通过 Markdown 和 Pandoc，可以做到编写一次，发布两次。 +> 通过 Markdown 和 Pandoc，可以做到编写一次，发布两次。 ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/email_paper_envelope_document.png?itok=uPj_kouJ) -Pandoc 是一个命令行工具，用于将文件从一种标记语言转换为另一种标记语言。在我的 [Pandoc 简介][1] 一文中，我演示了如何把 Markdown 编写的文本转换为网页、幻灯片和 PDF。 +Pandoc 是一个命令行工具，用于将文件从一种标记语言转换为另一种标记语言。在我 [对 Pandoc 的简介][1] 一文中，我演示了如何把 Markdown 编写的文本转换为网页、幻灯片和 PDF。 -在这篇后续文章中，我将深入探讨 [Pandoc][2]，展示如何从同一 Markdown 源文件生成网页和 ePub 格式的电子书。我将使用我即将发布的电子书-- [面向对象思想的 GRASP 原则][3] 为例进行讲解，这本电子书正是通过以下过程创建的。 +在这篇后续文章中，我将深入探讨 [Pandoc][2]，展示如何从同一个 Markdown 源文件生成网页和 ePub 格式的电子书。我将使用我即将发布的电子书《[面向对象思想的 GRASP 原则][3]》为例进行讲解，这本电子书正是通过以下过程创建的。 首先，我将解释这本书使用的文件结构，然后介绍如何使用 Pandoc 生成网页并将其部署在 GitHub 上；最后，我演示了如何生成对应的 ePub 格式电子书。 @@ -15,7 +15,7 @@ Pandoc 是一个命令行工具，用于将文件从一种标记语言转换为 ### 设置图书结构 -我用 Markdown 语法完成了所有的写作，你也可以使用 HTML，但是当 Pandoc 将 Markdown 转换为 ePub 文档时，引入的 HTML 越多，出现问题的风险就越高。我的书按照每章一个文件的形式进行组织，用 Markdown 的 `H1` 标记（`＃`）声明每章的标题。你也可以在每个文件中放置多个章节，但将它们放在单独的文件中可以更轻松地查找内容并在以后进行更新。 +我用 Markdown 语法完成了所有的写作，你也可以使用 HTML 标记，但是当 Pandoc 将 Markdown 转换为 ePub 文档时，引入的 HTML 标记越多，出现问题的风险就越高。我的书按照每章一个文件的形式进行组织，用 Markdown 的 `H1` 标记（`＃`）声明每章的标题。你也可以在每个文件中放置多个章节，但将它们放在单独的文件中可以更轻松地查找内容并在以后进行更新。 元信息遵循类似的模式，每种输出格式都有自己的元信息文件。元信息文件定义有关文档的信息，例如要添加到 HTML 中的文本或 ePub 的许可证。我将所有 Markdown 文档存储在名为 `parts` 的文件夹中（这对于用来生成网页和 ePub 的 Makefile 非常重要）。下面以一个例子进行说明，让我们看一下目录，前言和关于本书（分为 `toc.md`、`preface.md` 和 `about.md` 三个文件）这三部分，为清楚起见，我们将省略其余的章节。 @@ -48,60 +48,60 @@ author: Kiko Fernandez-Reyes rights: 2017 Kiko Fernandez-Reyes, CC-BY-NC-SA 4.0 International header-includes: - | -  \```{=html} -  -  -  \``` + ```{=html} + + + ``` include-before: - | -  \```{=html} - 

If you like this book, please consider -      spreading the word or -      -        buying me a coffee -      - 

-  \``` + ```{=html} +

If you like this book, please consider + spreading the word or + + buying me a coffee + +

+ ``` include-after: - | -  ```{=html} - 
-   
-   
-        -   
- 
-  \``` ----： + ```{=html} +
+
+
+ +
+
+ ``` +--- ``` 下面几个变量需要注意一下： - `header-includes` 变量包含将要嵌入 `` 标签的 HTML 文本。 -- 调用变量后的下一行必须是 `- |`。再往下一行必须以与`|`对齐的三个反引号开始，否则 Pandoc 将无法识别。`{= html}` 告诉 Pandoc 其中的内容是原始文本，不应该作为 Markdown 处理。（为此，需要检查 Pandoc 中的 `raw_attribute` 扩展是否已启用。要进行此检查，键入 `pandoc --list-extensions | grep raw` 并确保返回的列表包含名为 `+ raw_html` 的项目，加号表示已启用。） -- 变量 `include-before` 在网页开头添加一些 HTML 文本，此处我要求读者帮忙宣传我的书或给我打赏。 +- 调用变量后的下一行必须是 `- |`。再往下一行必须以与 `|` 对齐的三个反引号开始，否则 Pandoc 将无法识别。`{= html}` 告诉 Pandoc 其中的内容是原始文本，不应该作为 Markdown 处理。（为此，需要检查 Pandoc 中的 `raw_attribute` 扩展是否已启用。要进行此检查，键入 `pandoc --list-extensions | grep raw` 并确保返回的列表包含名为 `+ raw_html` 的项目，加号表示已启用。） +- 变量 `include-before` 在网页开头添加一些 HTML 文本，此处我请求读者帮忙宣传我的书或给我打赏。 - `include-after` 变量在网页末尾添加原始 HTML 文本，同时显示我的图书许可证。 这些只是其中一部分可用的变量，查看 HTML 中的模板变量（我的文章 [Pandoc简介][1] 中介绍了如何查看 LaTeX 的模版变量，查看 HTML 模版变量的过程是相同的）对其余变量进行了解。 #### 将网页分成多章 -网页可以作为一个整体生成，这会产生一个包含所有内容的长页面；也可以分成多章，我认为这样会更容易阅读。 我将解释如何将网页划分为多章，以便读者不会被长网页吓到。 +网页可以作为一个整体生成，这会产生一个包含所有内容的长页面；也可以分成多章，我认为这样会更容易阅读。我将解释如何将网页划分为多章，以便读者不会被长网页吓到。 为了使网页易于在 GitHub Pages 上部署，需要创建一个名为 `docs` 的根文件夹（这是 GitHub Pages 默认用于渲染网页的根文件夹）。然后我们需要为 `docs` 下的每一章创建文件夹，将 HTML 内容放在各自的文件夹中，将文件内容放在名为 `index.html` 的文件中。 例如，`about.md` 文件将转换成名为 `index.html` 的文件，该文件位于名为 `about`（`about/index.html`）的文件夹中。这样，当用户键入 `http:///about/` 时，文件夹中的 `index.html` 文件将显示在其浏览器中。 -下面的 Makefile 将执行上述所有操作： +下面的 `Makefile` 将执行上述所有操作： ``` # Your book files @@ -149,6 +149,7 @@ clean: ``` make ``` + 根文件夹现在应该包含如下所示的文件结构： ``` @@ -200,7 +201,7 @@ stylesheet: assets/epub.css ... ``` -将以下内容添加到之前的 Makefile 中： +将以下内容添加到之前的 `Makefile` 中： ``` epub: @@ -208,7 +209,7 @@ epub:         $(addprefix parts/, $(DEPENDENCIES:=.md)) -o $(DOCS)/assets/book.epub ``` -用于产生 ePub 格式图书的命令从 HTML 版本获取所有依赖项（每章的名称），向它们添加 Markdown 扩展，并在它们前面加上每一章的文件夹路径，以便让 Pandoc 知道如何进行处理。例如，如果 `$（DEPENDENCIES` 变量只包含 “前言” 和 “关于本书” 两章，那么 Makefile 将会这样调用： +用于产生 ePub 格式图书的命令从 HTML 版本获取所有依赖项（每章的名称），向它们添加 Markdown 扩展，并在它们前面加上每一章的文件夹路径，以便让 Pandoc 知道如何进行处理。例如，如果 `$（DEPENDENCIES` 变量只包含 “前言” 和 “关于本书” 两章，那么 `Makefile` 将会这样调用： ``` @pandoc -s --toc epub-meta.yaml \ @@ -226,18 +227,17 @@ Pandoc 将提取这两章的内容，然后进行组合，最后生成 ePub 格 - HTML 图书： - 使用 Markdown 语法创建每章内容 - 添加元信息 - - 创建一个 Makefile 将各个部分组合在一起 + - 创建一个 `Makefile` 将各个部分组合在一起 - 设置 GitHub Pages - 部署 - ePub 电子书： - 使用之前创建的每一章内容 - 添加新的元信息文件 - - 创建一个 Makefile 以将各个部分组合在一起 + - 创建一个 `Makefile` 以将各个部分组合在一起 - 设置 GitHub Pages - 部署 - ------ via: https://opensource.com/article/18/10/book-to-website-epub-using-pandoc @@ -245,12 +245,12 @@ via: https://opensource.com/article/18/10/book-to-website-epub-using-pandoc 作者：[Kiko Fernandez-Reyes][a] 选题：[lujun9972](https://github.com/lujun9972) 译者：[jlztan](https://github.com/jlztan) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 [a]: https://opensource.com/users/kikofernandez -[1]: https://opensource.com/article/18/9/intro-pandoc +[1]: https://linux.cn/article-10228-1.html [2]: https://pandoc.org/ [3]: https://www.programmingfightclub.com/ [4]: https://github.com/kikofernandez/programmingfightclub diff --git a/published/20181002 4 open source invoicing tools for small businesses.md b/published/201811/20181002 4 open source invoicing tools for small businesses.md similarity index 100% rename from published/20181002 4 open source invoicing tools for small businesses.md rename to published/201811/20181002 4 open source invoicing tools for small businesses.md diff --git a/translated/tech/20181002 Greg Kroah-Hartman Explains How the Kernel Community Is Securing Linux.md b/published/201811/20181002 Greg Kroah-Hartman Explains How the Kernel Community Is Securing Linux.md similarity index 67% rename from translated/tech/20181002 Greg Kroah-Hartman Explains How the Kernel Community Is Securing Linux.md rename to published/201811/20181002 Greg Kroah-Hartman Explains How the Kernel Community Is Securing Linux.md index a110960a9f..58996654e5 100644 --- a/translated/tech/20181002 Greg Kroah-Hartman Explains How the Kernel Community Is Securing Linux.md +++ b/published/201811/20181002 Greg Kroah-Hartman Explains How the Kernel Community Is Securing Linux.md @@ -1,42 +1,42 @@ -Greg Kroah-Hartman 解释内核社区如何保护 Linux -============================================================ +Greg Kroah-Hartman 解释内核社区是如何使 Linux 安全的 +============ ![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/kernel-security_0.jpg?itok=hOaTQwWV) -内核维护者 Greg Kroah-Hartman 谈论内核社区如何保护 Linux 不遭受损害。[Creative Commons Zero][2] -由于 Linux 使用量持续扩大，内核社区去提高全世界最广泛使用的技术 — Linux 内核的安全性的重要程序越来越高。安全不仅对企业客户很重要，它对消费者也很重要，因为 80% 的移动设备都使用了 Linux。在本文中，Linux 内核维护者 Greg Kroah-Hartman 带我们了解内核社区如何应对威胁。 +> 内核维护者 Greg Kroah-Hartman 谈论内核社区如何保护 Linux 不遭受损害。 + +由于 Linux 使用量持续扩大，内核社区去提高这个世界上使用最广泛的技术 —— Linux 内核的安全性的重要性越来越高。安全不仅对企业客户很重要，它对消费者也很重要，因为 80% 的移动设备都使用了 Linux。在本文中，Linux 内核维护者 Greg Kroah-Hartman 带我们了解内核社区如何应对威胁。 ### bug 不可避免 - ![Greg Kroah-Hartman](https://www.linux.com/sites/lcom/files/styles/floated_images/public/greg-k-h.png?itok=p4fREYuj "Greg Kroah-Hartman") -Greg Kroah-Hartman [Linux 基金会][1] +*Greg Kroah-Hartman [Linux 基金会][1]* -正如 Linus Torvalds 曾经说过，大多数安全问题都是 bug 造成的，而 bug 又是软件开发过程的一部分。是个软件就有 bug。 +正如 Linus Torvalds 曾经说过的，大多数安全问题都是 bug 造成的，而 bug 又是软件开发过程的一部分。是软件就有 bug。 -Kroah-Hartman 说：“就算是 bug ，我们也不知道它是安全的 bug 还是不安全的 bug。我修复的一个著名 bug，在三年后才被 Red Hat 认定为安全漏洞“。 +Kroah-Hartman 说：“就算是 bug，我们也不知道它是安全的 bug 还是不安全的 bug。我修复的一个著名 bug，在三年后才被 Red Hat 认定为安全漏洞“。 在消除 bug 方面，内核社区没有太多的办法，只能做更多的测试来寻找 bug。内核社区现在已经有了自己的安全团队，它们是由熟悉内核核心的内核开发者组成。 -Kroah Hartman 说：”当我们收到一个报告时，我们就让参与这个领域的核心开发者去修复它。在一些情况下，他们可能是同一个人，让他们进入安全团队可以更快地解决问题“。但他也强调，内核所有部分的开发者都必须清楚地了解这些问题，因为内核是一个可信环境，它必须被保护起来。 +Kroah-Hartman 说：”当我们收到一个报告时，我们就让参与这个领域的核心开发者去修复它。在一些情况下，他们可能是同一个人，让他们进入安全团队可以更快地解决问题“。但他也强调，内核所有部分的开发者都必须清楚地了解这些问题，因为内核是一个可信环境，它必须被保护起来。 -Kroah Hartman 说：”一旦我们修复了它，我们就将它放到我们的栈分析规则中，以便于以后不再重新出现这个 bug。“ +Kroah-Hartman 说：”一旦我们修复了它，我们就将它放到我们的栈分析规则中，以便于以后不再重新出现这个 bug。“ -除修复 bug 之外，内核社区也不断加固内核。Kroah Hartman 说：“我们意识到，我们需要一些主动的缓减措施。因此我们需要加固内核。” +除修复 bug 之外，内核社区也不断加固内核。Kroah-Hartman 说：“我们意识到，我们需要一些主动的缓减措施，因此我们需要加固内核。” -Kees Cook 和其他一些人付出了巨大的努力，带来了一直在内核之外的加固特性，并将它们合并或适配到内核中。在每个内核发行后，Cook 都对所有新的加固特性做一个总结。但是只加固内核是不够的，供应商必须要启用这些新特性来让它们充分发挥作用。但他们并没有这么做。 +Kees Cook 和其他一些人付出了巨大的努力，带来了一直在内核之外的加固特性，并将它们合并或适配到内核中。在每个内核发行后，Cook 都对所有新的加固特性做一个总结。但是只加固内核是不够的，供应商们必须要启用这些新特性来让它们充分发挥作用，但他们并没有这么做。 -Kroah-Hartman [每周发布一个稳定版内核][5]，而为了长周期的支持，公司只从中挑选一个，以便于设备制造商能够利用它。但是，Kroah-Hartman 注意到，除了 Google Pixel 之外，大多数 Android 手机并不包含这些额外的安全加固特性，这就意味着，所有的这些手机都是有漏洞的。他说：“人们应该去启用这些加固特性”。 +Kroah-Hartman [每周发布一个稳定版内核][5]，而为了长期的支持，公司们只从中挑选一个，以便于设备制造商能够利用它。但是，Kroah-Hartman 注意到，除了 Google Pixel 之外，大多数 Android 手机并不包含这些额外的安全加固特性，这就意味着，所有的这些手机都是有漏洞的。他说：“人们应该去启用这些加固特性”。 -Kroah-Hartman 说：“我购买了基于 Linux 内核 4.4 的所有旗舰级手机，去查看它们中哪些确实升级了新特性。结果我发现只有一家公司升级了它们的内核”。“我在整个供应链中努力去解决这个问题，因为这是一个很棘手的问题。它涉及许多不同的组织 — SoC 制造商、运营商、等等。关键点是，需要他们把我们辛辛苦苦设计的内核去推送给大家。 +Kroah-Hartman 说：“我购买了基于 Linux 内核 4.4 的所有旗舰级手机，去查看它们中哪些确实升级了新特性。结果我发现只有一家公司升级了它们的内核。……我在整个供应链中努力去解决这个问题，因为这是一个很棘手的问题。它涉及许多不同的组织 —— SoC 制造商、运营商等等。关键点是，需要他们把我们辛辛苦苦设计的内核去推送给大家。” -好消息是，与消息电子产品不一样，像 Red Hat 和 SUSE 这样的大供应商，在企业环境中持续对内核进行更新。使用容器、pod、和虚拟化的现代系统做到这一点更容易了。无需停机就可以毫不费力地更新和重启。事实上，现在来保证系统安全相比过去容易多了。 +好消息是，与消费电子产品不一样，像 Red Hat 和 SUSE 这样的大供应商，在企业环境中持续对内核进行更新。使用容器、pod 和虚拟化的现代系统做到这一点更容易了。无需停机就可以毫不费力地更新和重启。事实上，现在来保证系统安全相比过去容易多了。 ### Meltdown 和 Spectre -没有任何一个关于安全的讨论能够避免提及 Meltdown 和 Spectre。内核社区一直致力于修改新发现的和已查明的安全漏洞。不管怎样，Intel 已经因为这些事情改变了它们的策略。 +没有任何一个关于安全的讨论能够避免提及 Meltdown 和 Spectre 缺陷。内核社区一直致力于修改新发现的和已查明的安全漏洞。不管怎样，Intel 已经因为这些事情改变了它们的策略。 Kroah-Hartman 说：“他们已经重新研究如何处理安全 bug，以及如何与社区合作，因为他们知道他们做错了。内核已经修复了几乎所有大的 Spectre 问题，但是还有一些小问题仍在处理中”。 @@ -57,7 +57,7 @@ via: https://www.linux.com/blog/2018/10/greg-kroah-hartman-explains-how-kernel-c 作者：[SWAPNIL BHARTIYA][a] 选题：[oska874][b] 译者：[qhwdw](https://github.com/qhwdw) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20181004 Functional programming in Python- Immutable data structures.md b/published/201811/20181004 Functional programming in Python- Immutable data structures.md similarity index 100% rename from published/20181004 Functional programming in Python- Immutable data structures.md rename to published/201811/20181004 Functional programming in Python- Immutable data structures.md diff --git a/published/20181005 Terminalizer - A Tool To Record Your Terminal And Generate Animated Gif Images.md b/published/201811/20181005 Terminalizer - A Tool To Record Your Terminal And Generate Animated Gif Images.md similarity index 100% rename from published/20181005 Terminalizer - A Tool To Record Your Terminal And Generate Animated Gif Images.md rename to published/201811/20181005 Terminalizer - A Tool To Record Your Terminal And Generate Animated Gif Images.md diff --git a/published/20181006 LinuxBoot for Servers - Enter Open Source, Goodbye Proprietary UEFI.md b/published/201811/20181006 LinuxBoot for Servers - Enter Open Source, Goodbye Proprietary UEFI.md similarity index 100% rename from published/20181006 LinuxBoot for Servers - Enter Open Source, Goodbye Proprietary UEFI.md rename to published/201811/20181006 LinuxBoot for Servers - Enter Open Source, Goodbye Proprietary UEFI.md diff --git a/published/20181008 3 areas to drive DevOps change.md b/published/201811/20181008 3 areas to drive DevOps change.md similarity index 100% rename from published/20181008 3 areas to drive DevOps change.md rename to published/201811/20181008 3 areas to drive DevOps change.md diff --git a/published/20181008 KeeWeb - An Open Source, Cross Platform Password Manager.md b/published/201811/20181008 KeeWeb - An Open Source, Cross Platform Password Manager.md similarity index 100% rename from published/20181008 KeeWeb - An Open Source, Cross Platform Password Manager.md rename to published/201811/20181008 KeeWeb - An Open Source, Cross Platform Password Manager.md diff --git a/translated/tech/20181008 Play Windows games on Fedora with Steam Play and Proton.md b/published/201811/20181008 Play Windows games on Fedora with Steam Play and Proton.md similarity index 56% rename from translated/tech/20181008 Play Windows games on Fedora with Steam Play and Proton.md rename to published/201811/20181008 Play Windows games on Fedora with Steam Play and Proton.md index 26d315f64b..c0859f1dc1 100644 --- a/translated/tech/20181008 Play Windows games on Fedora with Steam Play and Proton.md +++ b/published/201811/20181008 Play Windows games on Fedora with Steam Play and Proton.md @@ -3,7 +3,7 @@ ![](https://fedoramagazine.org/wp-content/uploads/2018/09/steam-proton-816x345.jpg) -几周前，Steam 宣布要给 Steam Play 增加一个新组件，用于支持在 Linux 平台上使用 Proton 来玩 Windows 的游戏，这个组件是 WINE 的一个分支。这个功能仍然处于测试阶段，且并非对所有游戏都有效。这里有一些关于 Steam 和 Proton 的细节。 +之前，Steam [宣布][1]要给 Steam Play 增加一个新组件，用于支持在 Linux 平台上使用 Proton 来玩 Windows 的游戏，这个组件是 WINE 的一个分支。这个功能仍然处于测试阶段，且并非对所有游戏都有效。这里有一些关于 Steam 和 Proton 的细节。 据 Steam 网站称，测试版本中有以下这些新功能： @@ -13,29 +13,27 @@ * 改进了对游戏控制器的支持，游戏自动识别所有 Steam 支持的控制器，比起游戏的原始版本，能够获得更多开箱即用的控制器兼容性。 * 和 vanilla WINE 比起来，游戏的多线程性能得到了极大的提高。 - - ### 安装 如果你有兴趣，想尝试一下 Steam 和 Proton。请按照下面这些简单的步骤进行操作。（请注意，如果你已经安装了最新版本的 Steam，可以忽略启用 Steam 测试版这个第一步。在这种情况下，你不再需要通过 Steam 测试版来使用 Proton。） -打开 Steam 并登陆到你的帐户，这个截屏示例显示的是在使用 Proton 之前仅支持22个游戏。 +打开 Steam 并登陆到你的帐户，这个截屏示例显示的是在使用 Proton 之前仅支持 22 个游戏。 ![][3] -现在点击客户端顶部的 Steam 选项，这会显示一个下拉菜单。然后选择设置。 +现在点击客户端顶部的 “Steam” 选项，这会显示一个下拉菜单。然后选择“设置”。 ![][4] -现在弹出了设置窗口，选择账户选项，并在 Beta participation 旁边，点击更改。 +现在弹出了设置窗口，选择“账户”选项，并在 “参与 Beta 测试” 旁边，点击“更改”。 ![][5] -现在将 None 更改为 Steam Beta Update。 +现在将 “None” 更改为 “Steam Beta Update”。 ![][6] -点击确定，然后系统会提示你重新启动。 +点击“确定”，然后系统会提示你重新启动。 ![][7] @@ -43,11 +41,11 @@ ![][8] -在重新启动之后，返回到上面的设置窗口。这次你会看到一个新选项。确定有为提供支持的游戏使用 Stream Play 这个复选框，让所有的游戏都使用 Steam Play 进行运行，而不是 steam 中游戏特定的选项。兼容性工具应该是 Proton。 +在重新启动之后，返回到上面的设置窗口。这次你会看到一个新选项。确定勾选了“为提供支持的游戏使用 Stream Play” 、“让所有的游戏都使用 Steam Play 运行”，“使用这个工具替代 Steam 中游戏特定的选项”。这个兼容性工具应该就是 Proton。 ![][9] -Steam 客户端会要求你重新启动，照做，然后重新登陆你的 Steam 账户，你的 Linux 的游戏库就能得到扩展了。 +Steam 客户端会要求你重新启动，照做，然后重新登录你的 Steam 账户，你的 Linux 的游戏库就能得到扩展了。 ![][10] @@ -69,7 +67,7 @@ Steam 客户端会要求你重新启动，照做，然后重新登陆你的 Stea ![][16] -一些游戏可能会受到 Proton 测试性质的影响，在下面这个叫 Chantelise 游戏中，没有了声音并且帧率很低。请记住这个功能仍然在测试阶段，Fedora 不会对结果负责。如果你想要了解更多，社区已经创建了一个 Google 文档，这个文档里有已经测试过的游戏的列表。 +一些游戏可能会受到 Proton 测试性质的影响，在这个叫 Chantelise 游戏中，没有了声音并且帧率很低。请记住这个功能仍然在测试阶段，Fedora 不会对结果负责。如果你想要了解更多，社区已经创建了一个 Google 文档，这个文档里有已经测试过的游戏的列表。 -------------------------------------------------------------------------------- @@ -79,25 +77,25 @@ via: https://fedoramagazine.org/play-windows-games-steam-play-proton/ 作者：[Francisco J. Vergara Torres][a] 选题：[lujun9972](https://github.com/lujun9972) 译者：[hopefully2333](https://github.com/hopefully2333) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 [a]: https://fedoramagazine.org/author/patxi/ [1]: https://steamcommunity.com/games/221410/announcements/detail/1696055855739350561 [2]: https://fedoramagazine.org/third-party-repositories-fedora/ -[3]: https://fedoramagazine.org/wp-content/uploads/2018/09/listOfGamesLinux-300x197.png -[4]: https://fedoramagazine.org/wp-content/uploads/2018/09/1-300x169.png -[5]: https://fedoramagazine.org/wp-content/uploads/2018/09/2-300x196.png -[6]: https://fedoramagazine.org/wp-content/uploads/2018/09/4-300x272.png -[7]: https://fedoramagazine.org/wp-content/uploads/2018/09/6-300x237.png -[8]: https://fedoramagazine.org/wp-content/uploads/2018/09/7-300x126.png -[9]: https://fedoramagazine.org/wp-content/uploads/2018/09/10-300x237.png -[10]: https://fedoramagazine.org/wp-content/uploads/2018/09/12-300x196.png -[11]: https://fedoramagazine.org/wp-content/uploads/2018/09/13-300x196.png -[12]: https://fedoramagazine.org/wp-content/uploads/2018/09/14-300x195.png -[13]: https://fedoramagazine.org/wp-content/uploads/2018/09/15-300x196.png -[14]: https://fedoramagazine.org/wp-content/uploads/2018/09/16-300x195.png -[15]: https://fedoramagazine.org/wp-content/uploads/2018/09/Screenshot-from-2018-08-30-15-14-59-300x169.png -[16]: https://fedoramagazine.org/wp-content/uploads/2018/09/Screenshot-from-2018-08-30-15-19-34-300x169.png +[3]: https://fedoramagazine.org/wp-content/uploads/2018/09/listOfGamesLinux-768x505.png +[4]: https://fedoramagazine.org/wp-content/uploads/2018/09/1-768x432.png +[5]: https://fedoramagazine.org/wp-content/uploads/2018/09/2-768x503.png +[6]: https://fedoramagazine.org/wp-content/uploads/2018/09/4.png +[7]: https://fedoramagazine.org/wp-content/uploads/2018/09/6.png +[8]: https://fedoramagazine.org/wp-content/uploads/2018/09/7.png +[9]: https://fedoramagazine.org/wp-content/uploads/2018/09/10.png +[10]: https://fedoramagazine.org/wp-content/uploads/2018/09/12-768x503.png +[11]: https://fedoramagazine.org/wp-content/uploads/2018/09/13-768x501.png +[12]: https://fedoramagazine.org/wp-content/uploads/2018/09/14-768x498.png +[13]: https://fedoramagazine.org/wp-content/uploads/2018/09/15-768x501.png +[14]: https://fedoramagazine.org/wp-content/uploads/2018/09/16-768x500.png +[15]: https://fedoramagazine.org/wp-content/uploads/2018/09/Screenshot-from-2018-08-30-15-14-59-768x432.png +[16]: https://fedoramagazine.org/wp-content/uploads/2018/09/Screenshot-from-2018-08-30-15-19-34-768x432.png [17]: https://docs.google.com/spreadsheets/d/1DcZZQ4HL_Ol969UbXJmFG8TzOHNnHoj8Q1f8DIFe8-8/edit#gid=1003113831 diff --git a/published/20181010 5 alerting and visualization tools for sysadmins.md b/published/201811/20181010 5 alerting and visualization tools for sysadmins.md similarity index 100% rename from published/20181010 5 alerting and visualization tools for sysadmins.md rename to published/201811/20181010 5 alerting and visualization tools for sysadmins.md diff --git a/published/20181010 An introduction to using tcpdump at the Linux command line.md b/published/201811/20181010 An introduction to using tcpdump at the Linux command line.md similarity index 100% rename from published/20181010 An introduction to using tcpdump at the Linux command line.md rename to published/201811/20181010 An introduction to using tcpdump at the Linux command line.md diff --git a/published/20181014 How Lisp Became God-s Own Programming Language.md b/published/201811/20181014 How Lisp Became God-s Own Programming Language.md similarity index 94% rename from published/20181014 How Lisp Became God-s Own Programming Language.md rename to published/201811/20181014 How Lisp Became God-s Own Programming Language.md index 4666cad45e..017a67799f 100644 --- a/published/20181014 How Lisp Became God-s Own Programming Language.md +++ b/published/201811/20181014 How Lisp Became God-s Own Programming Language.md @@ -30,6 +30,8 @@ Lisp 是怎么成为上帝的编程语言的 > 我知道，上帝偏爱那一门 > 名字是四个字母的语言。 + +（LCTT 译注：参见 “四个字母”，参见：[四字神名](https://zh.wikipedia.org/wiki/%E5%9B%9B%E5%AD%97%E7%A5%9E%E5%90%8D)，致谢 [no1xsyzy](https://github.com/LCTT/TranslateProject/issues/11320)） 以下这句话我实在不好在人前说；不过，我还是觉得，这样一种 “Lisp 是奥术魔法”的文化模因实在是有史以来最奇异、最迷人的东西。Lisp 是象牙塔的产物，是人工智能研究的工具；因此，它对于编程界的俗人而言总是陌生的，甚至是带有神秘色彩的。然而，当今的程序员们[开始怂恿彼此，“在你死掉之前至少试一试 Lisp”][4]，就像这是一种令人恍惚入迷的致幻剂似的。尽管 Lisp 是广泛使用的编程语言中第二古老的（只比 Fortran 年轻一岁）[^1] ，程序员们也仍旧在互相怂恿。想象一下，如果你的工作是为某种组织或者团队推广一门新的编程语言的话，忽悠大家让他们相信你的新语言拥有神力难道不是绝佳的策略吗？—— 但你如何能够做到这一点呢？或者，换句话说，一门编程语言究竟是如何变成人们口中“隐晦知识的载体”的呢？ @@ -83,7 +85,7 @@ SICP 究竟有多奇怪这一点值得好好说；因为我认为，时至今日 *SICP 封面上的画作。* -说真的，这上面画的究竟是怎么一回事？为什么桌子会长着动物的腿？为什么这个女人指着桌子？墨水瓶又是干什么用的？我们是不是该说，这位巫师已经破译了宇宙的隐藏奥秘，而所有这些奥秘就蕴含在 eval/apply 循环和 Lambda 微积分之中？看似就是如此。单单是这张图片，就一定对人们如今谈论 Lisp 的方式产生了难以计量的影响。 +说真的，这上面画的究竟是怎么一回事？为什么桌子会长着动物的腿？为什么这个女人指着桌子？墨水瓶又是干什么用的？我们是不是该说，这位巫师已经破译了宇宙的隐藏奥秘，而所有这些奥秘就蕴含在 eval/apply 循环和 Lambda 演算之中？看似就是如此。单单是这张图片，就一定对人们如今谈论 Lisp 的方式产生了难以计量的影响。 然而，这本书的内容通常并不比封面正常多少。SICP 跟你读过的所有计算机科学教科书都不同。在引言中，作者们表示，这本书不只教你怎么用 Lisp 编程 —— 它是关于“现象的三个焦点：人的心智、复数的计算机程序，和计算机”的作品 [^19]。在之后，他们对此进行了解释，描述了他们对如下观点的坚信：编程不该被当作是一种计算机科学的训练，而应该是“程序性认识论procedural epistemology”的一种新表达方式 [^20]。程序是将那些偶然被送入计算机的思想组织起来的全新方法。这本书的第一章简明地介绍了 Lisp，但是之后的绝大部分都在讲述更加抽象的概念。其中包括了对不同编程范式的讨论，对于面向对象系统中“时间”和“一致性”的讨论；在书中的某一处，还有关于通信的基本限制可能会如何带来同步问题的讨论 —— 而这些基本限制在通信中就像是光速不变在相对论中一样关键 [^21]。都是些高深难懂的东西。 @@ -97,7 +99,7 @@ SICP 究竟有多奇怪这一点值得好好说；因为我认为，时至今日 理所当然地，确定人们对 Lisp 重新燃起热情的具体时间并不可能；但这多半是保罗·格雷厄姆发表他那几篇声称 Lisp 是首选入门语言的短文之后的事了。保罗·格雷厄姆是 Y-Combinator 的联合创始人和《Hacker News》的创始者，他这几篇短文有很大的影响力。例如，在短文《[胜于平庸][20]Beating the Averages》中，他声称 Lisp 宏使 Lisp 比其它语言更强。他说，因为他在自己创办的公司 Viaweb 中使用 Lisp，他得以比竞争对手更快地推出新功能。至少，[一部分程序员][21]被说服了。然而，庞大的主流程序员群体并未换用 Lisp。 -实际上出现的情况是，Lisp 并未流行，但越来越多 Lisp 式的特性被加入到广受欢迎的语言中。Python 有了列表理解。C# 有了 Linq。Ruby……嗯，[Ruby 是 Lisp 的一种][22]。就如格雷厄姆之前在 2001 年提到的那样，“在一系列常用语言中所体现出的‘默认语言’正越发朝着 Lisp 的方向演化” [^23]。尽管其它语言变得越来越像 Lisp，Lisp 本身仍然保留了其作为“很少人了解但是大家都该学的神秘语言”的特殊声望。在 1980 年，Lisp 的诞生二十周年纪念日上，麦卡锡写道，Lisp 之所以能够存活这么久，是因为它具备“编程语言领域中的某种近似局部最优” [^24]。这句话并未充分地表明 Lisp 的真正影响力。Lisp 能够存活超过半个世纪之久，并非因为程序员们一年年地勉强承认它就是最好的编程工具；事实上，即使绝大多数程序员根本不用它，它还是存活了下来。多亏了它的起源和它的人工智能研究用途，说不定还要多亏 SICP 的遗产，Lisp 一直都那么让人着迷。在我们能够想象上帝用其它新的编程语言创造世界之前，Lisp 都不会走下神坛。 +实际上出现的情况是，Lisp 并未流行，但越来越多 Lisp 式的特性被加入到广受欢迎的语言中。Python 有了列表推导式。C# 有了 Linq。Ruby……嗯，[Ruby 是 Lisp 的一种][22]。就如格雷厄姆之前在 2001 年提到的那样，“在一系列常用语言中所体现出的‘默认语言’正越发朝着 Lisp 的方向演化” [^23]。尽管其它语言变得越来越像 Lisp，Lisp 本身仍然保留了其作为“很少人了解但是大家都该学的神秘语言”的特殊声望。在 1980 年，Lisp 的诞生二十周年纪念日上，麦卡锡写道，Lisp 之所以能够存活这么久，是因为它具备“编程语言领域中的某种近似局部最优” [^24]。这句话并未充分地表明 Lisp 的真正影响力。Lisp 能够存活超过半个世纪之久，并非因为程序员们一年年地勉强承认它就是最好的编程工具；事实上，即使绝大多数程序员根本不用它，它还是存活了下来。多亏了它的起源和它的人工智能研究用途，说不定还要多亏 SICP 的遗产，Lisp 一直都那么让人着迷。在我们能够想象上帝用其它新的编程语言创造世界之前，Lisp 都不会走下神坛。 -------------------------------------------------------------------------------- diff --git a/published/20181015 How to Enable or Disable Services on Boot in Linux Using chkconfig and systemctl Command.md b/published/201811/20181015 How to Enable or Disable Services on Boot in Linux Using chkconfig and systemctl Command.md similarity index 100% rename from published/20181015 How to Enable or Disable Services on Boot in Linux Using chkconfig and systemctl Command.md rename to published/201811/20181015 How to Enable or Disable Services on Boot in Linux Using chkconfig and systemctl Command.md diff --git a/published/20181015 Kali Linux- What You Must Know Before Using it - FOSS Post.md b/published/201811/20181015 Kali Linux- What You Must Know Before Using it - FOSS Post.md similarity index 100% rename from published/20181015 Kali Linux- What You Must Know Before Using it - FOSS Post.md rename to published/201811/20181015 Kali Linux- What You Must Know Before Using it - FOSS Post.md diff --git a/published/20181017 Browsing the web with Min, a minimalist open source web browser.md b/published/201811/20181017 Browsing the web with Min, a minimalist open source web browser.md similarity index 100% rename from published/20181017 Browsing the web with Min, a minimalist open source web browser.md rename to published/201811/20181017 Browsing the web with Min, a minimalist open source web browser.md diff --git a/published/20181017 Chrony - An Alternative NTP Client And Server For Unix-like Systems.md b/published/201811/20181017 Chrony - An Alternative NTP Client And Server For Unix-like Systems.md similarity index 100% rename from published/20181017 Chrony - An Alternative NTP Client And Server For Unix-like Systems.md rename to published/201811/20181017 Chrony - An Alternative NTP Client And Server For Unix-like Systems.md diff --git a/published/20181017 Design faster web pages, part 2- Image replacement.md b/published/201811/20181017 Design faster web pages, part 2- Image replacement.md similarity index 100% rename from published/20181017 Design faster web pages, part 2- Image replacement.md rename to published/201811/20181017 Design faster web pages, part 2- Image replacement.md diff --git a/published/20181017 How To Determine Which System Manager Is Running On Linux System.md b/published/201811/20181017 How To Determine Which System Manager Is Running On Linux System.md similarity index 100% rename from published/20181017 How To Determine Which System Manager Is Running On Linux System.md rename to published/201811/20181017 How To Determine Which System Manager Is Running On Linux System.md diff --git a/published/20181019 Edit your videos with Pitivi on Fedora.md b/published/201811/20181019 Edit your videos with Pitivi on Fedora.md similarity index 100% rename from published/20181019 Edit your videos with Pitivi on Fedora.md rename to published/201811/20181019 Edit your videos with Pitivi on Fedora.md diff --git a/published/20181019 How to use Pandoc to produce a research paper.md b/published/201811/20181019 How to use Pandoc to produce a research paper.md similarity index 100% rename from published/20181019 How to use Pandoc to produce a research paper.md rename to published/201811/20181019 How to use Pandoc to produce a research paper.md diff --git a/translated/talk/20181019 What is an SRE and how does it relate to DevOps.md b/published/201811/20181019 What is an SRE and how does it relate to DevOps.md similarity index 83% rename from translated/talk/20181019 What is an SRE and how does it relate to DevOps.md rename to published/201811/20181019 What is an SRE and how does it relate to DevOps.md index 80700d6fb9..03bd773fa7 100644 --- a/translated/talk/20181019 What is an SRE and how does it relate to DevOps.md +++ b/published/201811/20181019 What is an SRE and how does it relate to DevOps.md @@ -1,15 +1,15 @@ 什么是 SRE？它和 DevOps 是怎么关联的？ ===== -大型企业里 SRE 角色比较常见，不过小公司也需要 SRE。 +> 大型企业里 SRE 角色比较常见，不过小公司也需要 SRE。 ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/toolbox-learn-draw-container-yearbook.png?itok=xDbwz1pP) -虽然站点可靠性工程师（SRE）角色在近几年变得流行起来，但是很多人 —— 甚至是软件行业里的 —— 还不知道 SRE 是什么或者 SRE 都干些什么。为了搞清楚这些问题，这篇文章解释了 SRE 的含义，还有 SRE 怎样关联 DevOps，以及在工程师团队规模不大的组织里 SRE 该如何工作。 +虽然站点可靠性工程师site reliability engineer（SRE）角色在近几年变得流行起来，但是很多人 —— 甚至是软件行业里的 —— 还不知道 SRE 是什么或者 SRE 都干些什么。为了搞清楚这些问题，这篇文章解释了 SRE 的含义，还有 SRE 怎样关联 DevOps，以及在工程师团队规模不大的组织里 SRE 该如何工作。 ### 什么是站点可靠性工程？ -谷歌的几个工程师写的《 [SRE：谷歌运维解密][1]》被认为是站点可靠性工程的权威书籍。谷歌的工程副总裁 Ben Treynor Sloss 在二十一世纪初[创造了这个术语][2]。他是这样定义的：“当你让软件工程师设计运维功能时，SRE 就产生了。” +谷歌的几个工程师写的《[SRE：谷歌运维解密][1]》被认为是站点可靠性工程的权威书籍。谷歌的工程副总裁 Ben Treynor Sloss 在二十一世纪初[创造了这个术语][2]。他是这样定义的：“当你让软件工程师设计运维功能时，SRE 就产生了。” 虽然系统管理员从很久之前就在写代码，但是过去的很多时候系统管理团队是手动管理机器的。当时他们管理的机器可能有几十台或者上百台，不过当这个数字涨到了几千甚至几十万的时候，就不能简单的靠人去解决问题了。规模如此大的情况下，很明显应该用代码去管理机器（以及机器上运行的软件）。 @@ -19,13 +19,13 @@ ### SRE 和 DevOps -站点可靠性工程的核心，就是对 DevOps 范例的实践。[DevOps 的定义][3]有很多种方式。开发团队（“devs”）和运维（“ops”）团队相互分离的传统模式下，写代码的团队在服务交付给用户使用之后就不再对服务状态负责了。开发团队“把代码扔到墙那边”让运维团队去部署和支持。 +站点可靠性工程的核心，就是对 DevOps 范例的实践。[DevOps 的定义][3]有很多种方式。开发团队（“dev”）和运维（“ops”）团队相互分离的传统模式下，写代码的团队在将服务交付给用户使用之后就不再对服务状态负责了。开发团队“把代码扔到墙那边”让运维团队去部署和支持。 这种情况会导致大量失衡。开发和运维的目标总是不一致 —— 开发希望用户体验到“最新最棒”的代码，但是运维想要的是变更尽量少的稳定系统。运维是这样假定的，任何变更都可能引发不稳定，而不做任何变更的系统可以一直保持稳定。（减少软件的变更次数并不是避免故障的唯一因素，认识到这一点很重要。例如，虽然你的 web 应用保持不变，但是当用户数量涨到十倍时，服务可能就会以各种方式出问题。） DevOps 理念认为通过合并这两个岗位就能够消灭争论。如果开发团队时刻都想把新代码部署上线，那么他们也必须对新代码引起的故障负责。就像亚马逊的 [Werner Vogels 说的][4]那样，“谁开发，谁运维”（生产环境）。但是开发人员已经有一大堆问题了。他们不断的被推动着去开发老板要的产品功能。再让他们去了解基础设施，包括如何部署、配置还有监控服务，这对他们的要求有点太多了。所以就需要 SRE 了。 -开发一个 web 应用的时候经常是很多人一起参与。有用户界面设计师，图形设计师，前端工程师，后端工程师，还有许多其他工种（视技术选型的具体情况而定）。如何管理写好的代码也是需求之一（例如部署，配置，监控）—— 这是 SRE 的专业领域。但是，就像前端工程师受益于后端领域的知识一样（例如从数据库获取数据的方法），SRE 理解部署系统的工作原理，知道如何满足特定的代码或者项目的具体需求。 +开发一个 web 应用的时候经常是很多人一起参与。有用户界面设计师、图形设计师、前端工程师、后端工程师，还有许多其他工种（视技术选型的具体情况而定）。如何管理写好的代码也是需求之一（例如部署、配置、监控）—— 这是 SRE 的专业领域。但是，就像前端工程师受益于后端领域的知识一样（例如从数据库获取数据的方法），SRE 理解部署系统的工作原理，知道如何满足特定的代码或者项目的具体需求。 所以 SRE 不仅仅是“写代码的运维工程师”。相反，SRE 是开发团队的成员，他们有着不同的技能，特别是在发布部署、配置管理、监控、指标等方面。但是，就像前端工程师必须知道如何从数据库中获取数据一样，SRE 也不是只负责这些领域。为了提供更容易升级、管理和监控的产品，整个团队共同努力。 @@ -37,7 +37,7 @@ DevOps 理念认为通过合并这两个岗位就能够消灭争论。如果开 让开发人员做 SRE 最显著的优点是，团队规模变大的时候也能很好的扩展。而且，开发人员将会全面地了解应用的特性。但是，许多初创公司的基础设施包含了各种各样的 SaaS 产品，这种多样性在基础设施上体现的最明显，因为连基础设施本身也是多种多样。然后你们在某个基础设施上引入指标系统、站点监控、日志分析、容器等等。这些技术解决了一部分问题，也增加了复杂度。开发人员除了要了解应用程序的核心技术（比如开发语言），还要了解上述所有技术和服务。最终，掌握所有的这些技术让人无法承受。 -另一种方案是聘请专家专职做 SRE。他们专注于发布部署、配置管理、监控和指标，可以节省开发人员的时间。这种方案的缺点是，SRE 的时间必须分配给多个不同的应用（就是说 SRE 需要贯穿整个工程部门）。 这可能意味着 SRE 没时间对任何应用深入学习，然而他们可以站在一个能看到服务全貌的高度，知道各个部分是怎么组合在一起的。 这个“ 三万英尺高的视角”可以帮助 SRE 从系统整体上考虑，哪些薄弱环节需要优先修复。 +另一种方案是聘请专家专职做 SRE。他们专注于发布部署、配置管理、监控和指标，可以节省开发人员的时间。这种方案的缺点是，SRE 的时间必须分配给多个不同的应用（就是说 SRE 需要贯穿整个工程部门）。 这可能意味着 SRE 没时间对任何应用深入学习，然而他们可以站在一个能看到服务全貌的高度，知道各个部分是怎么组合在一起的。 这个“三万英尺高的视角”可以帮助 SRE 从系统整体上考虑，哪些薄弱环节需要优先修复。 有一个关键信息我还没提到：其他的工程师。他们可能很渴望了解发布部署的原理，也很想尽全力学会使用指标系统。而且，雇一个 SRE 可不是一件简单的事儿。因为你要找的是一个既懂系统管理又懂软件工程的人。（我之所以明确地说软件工程而不是说“能写代码”，是因为除了写代码之外软件工程还包括很多东西，比如编写良好的测试或文档。） @@ -54,7 +54,7 @@ via: https://opensource.com/article/18/10/sre-startup 作者：[Craig Sebenik][a] 选题：[lujun9972][b] 译者：[BeliteX](https://github.com/belitex) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20181022 5 tips for choosing the right open source database.md b/published/201811/20181022 5 tips for choosing the right open source database.md similarity index 100% rename from published/20181022 5 tips for choosing the right open source database.md rename to published/201811/20181022 5 tips for choosing the right open source database.md diff --git a/published/20181022 How to set up WordPress on a Raspberry Pi.md b/published/201811/20181022 How to set up WordPress on a Raspberry Pi.md similarity index 100% rename from published/20181022 How to set up WordPress on a Raspberry Pi.md rename to published/201811/20181022 How to set up WordPress on a Raspberry Pi.md diff --git a/published/20181023 Getting started with functional programming in Python using the toolz library.md b/published/201811/20181023 Getting started with functional programming in Python using the toolz library.md similarity index 100% rename from published/20181023 Getting started with functional programming in Python using the toolz library.md rename to published/201811/20181023 Getting started with functional programming in Python using the toolz library.md diff --git a/published/20181024 4 cool new projects to try in COPR for October 2018.md b/published/201811/20181024 4 cool new projects to try in COPR for October 2018.md similarity index 100% rename from published/20181024 4 cool new projects to try in COPR for October 2018.md rename to published/201811/20181024 4 cool new projects to try in COPR for October 2018.md diff --git a/published/20181024 Get organized at the Linux command line with Calcurse.md b/published/201811/20181024 Get organized at the Linux command line with Calcurse.md similarity index 100% rename from published/20181024 Get organized at the Linux command line with Calcurse.md rename to published/201811/20181024 Get organized at the Linux command line with Calcurse.md diff --git a/published/20181025 Monitoring database health and behavior- Which metrics matter.md b/published/201811/20181025 Monitoring database health and behavior- Which metrics matter.md similarity index 100% rename from published/20181025 Monitoring database health and behavior- Which metrics matter.md rename to published/201811/20181025 Monitoring database health and behavior- Which metrics matter.md diff --git a/published/20181025 Understanding Linux Links- Part 2.md b/published/201811/20181025 Understanding Linux Links- Part 2.md similarity index 100% rename from published/20181025 Understanding Linux Links- Part 2.md rename to published/201811/20181025 Understanding Linux Links- Part 2.md diff --git a/translated/talk/20181025 What breaks our systems- A taxonomy of black swans.md b/published/201811/20181025 What breaks our systems- A taxonomy of black swans.md similarity index 83% rename from translated/talk/20181025 What breaks our systems- A taxonomy of black swans.md rename to published/201811/20181025 What breaks our systems- A taxonomy of black swans.md index 22d2bdd3df..e3aa38e75a 100644 --- a/translated/talk/20181025 What breaks our systems- A taxonomy of black swans.md +++ b/published/201811/20181025 What breaks our systems- A taxonomy of black swans.md @@ -1,27 +1,27 @@ 让系统崩溃的黑天鹅分类 ====== -在严重的故障发生之前，找到引起问题的异常事件，并修复它。 +> 在严重的故障发生之前，找到引起问题的异常事件，并修复它。 ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/black-swan-pair_0.png?itok=MkshwqVg) -黑天鹅用来比喻造成严重影响的小概率事件（比如 2008 年的金融危机）。在生产环境的系统中，黑天鹅是指这样的事情：它引发了你不知道的问题，造成了重大影响，不能快速修复或回滚，也不能用值班说明书上的其他标准响应来解决。它是事发几年后你还在给新人说起的事件。 +黑天鹅Black swan用来比喻造成严重影响的小概率事件（比如 2008 年的金融危机）。在生产环境的系统中，黑天鹅是指这样的事情：它引发了你不知道的问题，造成了重大影响，不能快速修复或回滚，也不能用值班说明书上的其他标准响应来解决。它是事发几年后你还在给新人说起的事件。 从定义上看，黑天鹅是不可预测的，不过有时候我们能找到其中的一些模式，针对有关联的某一类问题准备防御措施。 -例如，大部分故障的直接原因是变更（代码、环境或配置）。虽然这种方式触发的 bug 是独特的，不可预测的，但是常见的金丝雀发布对避免这类问题有一定的作用，而且自动回滚已经成了一种标准止损策略。 +例如，大部分故障的直接原因是变更（代码、环境或配置）。虽然这种方式触发的 bug 是独特的、不可预测的，但是常见的金丝雀发布对避免这类问题有一定的作用，而且自动回滚已经成了一种标准止损策略。 随着我们的专业性不断成熟，一些其他的问题也正逐渐变得容易理解，被归类到某种风险并有普适的预防策略。 ### 公布出来的黑天鹅事件 -所有科技公司都有生产环境的故障，只不过并不是所有公司都会分享他们的事故分析。那些公开讨论事故的公司帮了我们的忙。下列事故都描述了某一类问题，但它们绝对不是只属于一个类别。我们的系统中都有黑天鹅在潜伏着，只是有些人还不知道而已。 +所有科技公司都有生产环境的故障，只不过并不是所有公司都会分享他们的事故分析。那些公开讨论事故的公司帮了我们的忙。下列事故都描述了某一类问题，但它们绝对不是只一个孤例。我们的系统中都有黑天鹅在潜伏着，只是有些人还不知道而已。 #### 达到上限 达到任何类型的限制都会引发严重事故。这类问题的一个典型例子是 2017 年 2 月 [Instapaper 的一次服务中断][1]。我把这份事故报告给任何一个运维工作者看，他们读完都会脊背发凉。Instapaper 生产环境的数据库所在的文件系统有 2 TB 的大小限制，但是数据库服务团队并不知情。在没有任何报错的情况下，数据库不再接受任何写入了。完全恢复需要好几天，而且还得迁移数据库。 -资源限制有各式各样的触发场景。Sentry 遇到了 [Postgres 的最大事务 ID 限制][2]。Platform.sh 遇到了[管道缓冲区大小限制][3]。SparkPost [触发了 AWS 的 DDos 保护][4]。Foursquare 在他们的一个 [MongoDB 耗尽内存][5]时遭遇了性能骤降。 +资源限制有各式各样的触发场景。Sentry 遇到了 [Postgres 的最大事务 ID 限制][2]。Platform.sh 遇到了[管道缓冲区大小限制][3]。SparkPost [触发了 AWS 的 DDoS 保护][4]。Foursquare 在他们的一个 [MongoDB 耗尽内存][5]时遭遇了性能骤降。 提前了解系统限制的一个办法是定期做测试。好的压力测试（在生产环境的副本上做）应该包含写入事务，并且应该把每一种数据存储都写到超过当前生产环境的容量。压力测试时很容易忽略的是次要存储（比如 Zookeeper）。如果你是在测试时遇到了资源限制，那么你还有时间去解决问题。鉴于这种资源限制问题的解决方案可能涉及重大的变更（比如数据存储拆分），所以时间是非常宝贵的。 @@ -32,7 +32,7 @@ #### 扩散的慢请求 > “这个世界的关联性远比我们想象中更大。所以我们看到了更多 Nassim Taleb 所说的‘黑天鹅事件’ —— 即罕见事件以更高的频率离谱地发生了，因为世界是相互关联的” -> — [Richard Thaler][6] +> —— [Richard Thaler][6] HostedGraphite 的负载均衡器并没有托管在 AWS 上，却[被 AWS 的服务中断给搞垮了][7]，他们关于这次事故原因的分析报告很好地诠释了分布式计算系统之间存在多么大的关联。在这个事件里，负载均衡器的连接池被来自 AWS 上的客户访问占满了，因为这些连接很耗时。同样的现象还会发生在应用的线程、锁、数据库连接上 —— 任何能被慢操作占满的资源。 @@ -40,7 +40,7 @@ HostedGraphite 的负载均衡器并没有托管在 AWS 上，却[被 AWS 的服 重试的间隔应该用指数退避来限制一下，并加入一些时间抖动。Square 有一次服务中断是 [Redis 存储的过载][9]，原因是有一段代码对失败的事务重试了 500 次，没有任何重试退避的方案，也说明了过度重试的潜在风险。另外，针对这种情况，[断路器][10]设计模式也是有用的。 -应该设计出监控仪表盘来清晰地展示所有资源的[使用率，饱和度和报错][11]，这样才能快速发现问题。 +应该设计出监控仪表盘来清晰地展示所有资源的[使用率、饱和度和报错][11]，这样才能快速发现问题。 #### 突发的高负载 @@ -48,7 +48,7 @@ HostedGraphite 的负载均衡器并没有托管在 AWS 上，却[被 AWS 的服 在预定时刻同时发生的事件并不是突发大流量的唯一原因。Slack 经历过一次短时间内的[多次服务中断][12]，原因是非常多的客户端断开连接后立即重连，造成了突发的大负载。 CircleCI 也经历过一次[严重的服务中断][13]，当时 Gitlab 从故障中恢复了，所以数据库里积累了大量的构建任务队列，服务变得饱和而且缓慢。 -几乎所有的服务都会受突发的高负载所影响。所以对这类可能出现的事情做应急预案——并测试一下预案能否正常工作——是必须的。客户端退避和[减载][14]通常是这些方案的核心。 +几乎所有的服务都会受突发的高负载所影响。所以对这类可能出现的事情做应急预案 —— 并测试一下预案能否正常工作 —— 是必须的。客户端退避和[减载][14]通常是这些方案的核心。 如果你的系统必须不间断地接收数据，并且数据不能被丢掉，关键是用可伸缩的方式把数据缓冲到队列中，后续再处理。 @@ -57,7 +57,7 @@ HostedGraphite 的负载均衡器并没有托管在 AWS 上，却[被 AWS 的服 > “复杂的系统本身就是有风险的系统” > —— [Richard Cook, MD][15] -过去几年里软件的运维操作趋势是更加自动化。任何可能降低系统容量的自动化操作（比如擦除磁盘，退役设备，关闭服务）都应该谨慎操作。这类自动化操作的故障（由于系统有 bug 或者有不正确的调用）能很快地搞垮你的系统，而且可能很难恢复。 +过去几年里软件的运维操作趋势是更加自动化。任何可能降低系统容量的自动化操作（比如擦除磁盘、退役设备、关闭服务）都应该谨慎操作。这类自动化操作的故障（由于系统有 bug 或者有不正确的调用）能很快地搞垮你的系统，而且可能很难恢复。 谷歌的 Christina Schulman 和 Etienne Perot 在[用安全规约协助保护你的数据中心][16]的演讲中给了一些例子。其中一次事故是将谷歌整个内部的内容分发网络（CDN）提交给了擦除磁盘的自动化系统。 @@ -69,11 +69,11 @@ Schulman 和 Perot 建议使用一个中心服务来管理规约，限制破坏 ### 防止黑天鹅事件 -可能在等着击垮系统的黑天鹅可不止上面这些。有很多其他的严重问题是能通过一些技术来避免的，像金丝雀发布，压力测试，混沌工程，灾难测试和模糊测试——当然还有冗余性和弹性的设计。但是即使用了这些技术，有时候你的系统还是会有故障。 +可能在等着击垮系统的黑天鹅可不止上面这些。有很多其他的严重问题是能通过一些技术来避免的，像金丝雀发布、压力测试、混沌工程、灾难测试和模糊测试 —— 当然还有冗余性和弹性的设计。但是即使用了这些技术，有时候你的系统还是会有故障。 -为了确保你的组织能有效地响应，在服务中断期间，请保证关键技术人员和领导层有办法沟通协调。例如，有一种你可能需要处理的烦人的事情，那就是网络完全中断。拥有故障时仍然可用的通信通道非常重要，这个通信通道要完全独立于你们自己的基础设施和基础设施的依赖。举个例子，假如你使用 AWS，那么把故障时可用的通信服务部署在 AWS 上就不明智了。在和你的主系统无关的地方，运行电话网桥或 IRC 服务器是比较好的方案。确保每个人都知道这个通信平台，并练习使用它。 +为了确保你的组织能有效地响应，在服务中断期间，请保证关键技术人员和领导层有办法沟通协调。例如，有一种你可能需要处理的烦人的事情，那就是网络完全中断。拥有故障时仍然可用的通信通道非常重要，这个通信通道要完全独立于你们自己的基础设施及对其的依赖。举个例子，假如你使用 AWS，那么把故障时可用的通信服务部署在 AWS 上就不明智了。在和你的主系统无关的地方，运行电话网桥或 IRC 服务器是比较好的方案。确保每个人都知道这个通信平台，并练习使用它。 -另一个原则是，确保监控和运维工具对生产环境系统的依赖尽可能的少。将控制平面和数据平面分开，你才能在系统不健康的时候做变更。不要让数据处理和配置变更或监控使用同一个消息队列，比如——应该使用不同的消息队列实例。在 [SparkPost: DNS 挂掉的那一天][4] 这个演讲中，Jeremy Blosser 讲了一个这类例子，很关键的工具依赖了生产环境的 DNS 配置，但是生产环境的 DNS 出了问题。 +另一个原则是，确保监控和运维工具对生产环境系统的依赖尽可能的少。将控制平面和数据平面分开，你才能在系统不健康的时候做变更。不要让数据处理和配置变更或监控使用同一个消息队列，比如，应该使用不同的消息队列实例。在 [SparkPost: DNS 挂掉的那一天][4] 这个演讲中，Jeremy Blosser 讲了一个这类例子，很关键的工具依赖了生产环境的 DNS 配置，但是生产环境的 DNS 出了问题。 ### 对抗黑天鹅的心理学 @@ -83,7 +83,7 @@ Schulman 和 Perot 建议使用一个中心服务来管理规约，限制破坏 ### 了解更多 -关于黑天鹅（或者以前的黑天鹅）事件以及应对策略，还有很多其他的事情可以说。如果你想了解更多，我强烈推荐你去看这两本书，它们是关于生产环境中的弹性和稳定性的：Susan Fowler 写的[生产微服务][19]，还有 Michael T. Nygard 的 [Release It!][20]。 +关于黑天鹅（或者以前的黑天鹅）事件以及应对策略，还有很多其他的事情可以说。如果你想了解更多，我强烈推荐你去看这两本书，它们是关于生产环境中的弹性和稳定性的：Susan Fowler 写的《[生产微服务][19]》，还有 Michael T. Nygard 的 《[Release It!][20]》。 -------------------------------------------------------------------------------- @@ -92,7 +92,7 @@ via: https://opensource.com/article/18/10/taxonomy-black-swans 作者：[Laura Nolan][a] 选题：[lujun9972][b] 译者：[BeliteX](https://github.com/belitex) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/translated/tech/20181026 An Overview of Android Pie.md b/published/201811/20181026 An Overview of Android Pie.md similarity index 81% rename from translated/tech/20181026 An Overview of Android Pie.md rename to published/201811/20181026 An Overview of Android Pie.md index 9eb3ea5206..7aae6a1f0f 100644 --- a/translated/tech/20181026 An Overview of Android Pie.md +++ b/published/201811/20181026 An Overview of Android Pie.md @@ -1,40 +1,38 @@ Android 9.0 概览 ====== +> 第九代 Android 带来了更令人满意的用户体验。 + ![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/android-pie.jpg?itok=Sx4rbOWY) -我们来谈论一下 Android。尽管 Android 只是一款内核经过修改的 Linux，但经过多年的发展，Android 开发者们（或许包括正在阅读这篇文章的你）已经为这个平台的演变做出了很多值得称道的贡献。当然，可能很多人都已经知道，但我们还是要说，Android 并不完全开源，当你使用 Google 服务的时候，就已经接触到闭源的部分了。Google Play 商店就是其中之一，它不是一个开放的服务，不过这与 Android 是否开源没有太直接的联系，而是为了让你享用到美味、营养、高效、省电的馅饼（注：Android 9.0 代号为 Pie）。 +我们来谈论一下 Android。尽管 Android 只是一款内核经过修改的 Linux，但经过多年的发展，Android 开发者们（或许包括正在阅读这篇文章的你）已经为这个平台的演变做出了很多值得称道的贡献。当然，可能很多人都已经知道，但我们还是要说，Android 并不完全开源，当你使用 Google 服务的时候，就已经接触到闭源的部分了。Google Play 商店就是其中之一，它不是一个开放的服务。不过无论 Android 开源与否，这就是一个美味、营养、高效、省电的馅饼（LCTT 译注：Android 9.0 代号为 Pie）。 -我在我的 Essential PH-1 手机上运行了 Android 9.0（我真的很喜欢这款手机，也很了解这家公司的境况并不好）。在我自己体验了一段时间之后，我认为它是会被大众接受的。那么 Android 9.0 到底好在哪里呢？下面我们就来深入探讨一下。我们的出发点是用户的角度，而不是开发人员的角度，因此我也不会深入探讨太底层的方面。 +我在我的 Essential PH-1 手机上运行了 Android 9.0（我真的很喜欢这款手机，也知道这家公司的境况并不好）。在我自己体验了一段时间之后，我认为它是会被大众接受的。那么 Android 9.0 到底好在哪里呢？下面我们就来深入探讨一下。我们的出发点是用户的角度，而不是开发人员的角度，因此我也不会深入探讨太底层的方面。 ### 手势操作 Android 系统在新的手势操作方面投入了很多，但实际体验却不算太好。这个功能确实引起了我的兴趣。在这个功能发布之初，大家都对它了解甚少，纷纷猜测它会不会让用户使用多点触控的手势来浏览 Android 界面？又或者会不会是一个完全颠覆人们认知的东西？ -实际上，手势操作比大多数人设想的要更加微妙和简单，因为很多功能都浓缩到了 Home 键上。打开手势操作功能之后，Recent 键的功能就合并到 Home 键上了。因此，如果需要查看最近打开的应用程序，就不能简单地通过 Recent 键来查看，而应该从 Home 键向上轻扫一下。（图1） +实际上，手势操作比大多数人设想的要更加微妙而简单，因为很多功能都浓缩到了 Home 键上。打开手势操作功能之后，Recent 键的功能就合并到 Home 键上了。因此，如果需要查看最近打开的应用程序，就不能简单地通过 Recent 键来查看，而应该从 Home 键向上轻扫一下。（图 1） ![Android Pie][2] -图 1：Android 9.0 中的”最近的应用程序“界面。 +*图 1：Android 9.0 中的”最近的应用程序“界面。* 另一个不同的地方是 App Drawer。类似于查看最近打开的应用，需要在 Home 键向上滑动才能打开 App Drawer。 -而后退按钮则没有去掉。在应用程序需要用到后退功能时，它就会出现在屏幕的左下方。有时候即使应用程序自己带有后退按钮，Android 的后退按钮也会出现。 +而后退按钮则没有去掉。在应用程序需要用到后退功能时，它就会出现在主屏幕的左下方。有时候即使应用程序自己带有后退按钮，Android 的后退按钮也会出现。 当然，如果你不喜欢使用手势操作，也可以禁用这个功能。只需要按照下列步骤操作： - 1. 打开”设置“ - - 2. 向下滑动并进入 系统 > 手势 - + 2. 向下滑动并进入“系统 > 手势” 3. 从 Home 键向上滑动 - - 4. 将 On/Off 滑块（图2）滑动至 Off 位置 + 4. 将 On/Off 滑块（图 2）滑动至 Off 位置 ![](https://www.linux.com/sites/lcom/files/styles/floated_images/public/pie_2.png?itok=cs2tqZut) -图 2：关闭手势操作。 +*图 2：关闭手势操作。* ### 电池寿命 @@ -42,25 +40,19 @@ Android 系统在新的手势操作方面投入了很多，但实际体验却不 对于这个功能的唯一一个警告是，如果人工智能出现问题并导致电池电量过早耗尽，就只能通过恢复出厂设置来解决这个问题了。尽管有这样的缺陷，在电池续航时间方面，Android 9.0 也比 Android 8.0 有所改善。 -### 分屏功能 +### 分屏功能的变化 分屏对于 Android 来说不是一个新功能，但在 Android 9.0 上，它的使用方式和以往相比略有不同，而且只对于手势操作有影响，不使用手势操作的用户不受影响。要在 Android 9.0 上使用分屏功能，需要按照下列步骤操作： + 1. 从 Home 键向上滑动，打开“最近的应用程序”。 + 2. 找到需要放置在屏幕顶部的应用程序。 + 3. 长按应用程序顶部的图标以显示新的弹出菜单。（图 3） + 4. 点击分屏，应用程序会在屏幕的上半部分打开。 + 5. 找到要打开的第二个应用程序，然后点击它添加到屏幕的下半部分。 + ![Adding an app][5] -图 3：在 Android 9.0 上将应用添加到分屏模式中。 - -[Used with permission][3] - - 1. 从 Home 键向上滑动，打开“最近的应用程序”。 - - 2. 找到需要放置在屏幕顶部的应用程序。 - - 3. 长按应用程序顶部的图标以显示新的弹出菜单。（图 3） - - 4. 点击分屏，应用程序会在屏幕的上半部分打开。 - - 5. 找到要打开的第二个应用程序，然后点击它添加到屏幕的下半部分。 +*图 3：在 Android 9.0 上将应用添加到分屏模式中。* 使用分屏功能关闭应用程序的方法和原来保持一致。 @@ -72,7 +64,7 @@ Android 系统在新的手势操作方面投入了很多，但实际体验却不 ![Actions][7] -图 4：Android 应用操作。 +*图 4：Android 应用操作。* ### 声音控制 @@ -82,17 +74,17 @@ Android 9.0 这次优化针对的是设备上快速控制声音的按钮。如 ![Sound control][9] -图 5：Android 9.0 上的声音控制。 +*图 5：Android 9.0 上的声音控制。* ### 屏幕截图 -由于我要撰写关于 Android 的文章，所以我会常常需要进行屏幕截图。而 Android 9.0 有意向我最喜欢的更新，就是分享屏幕截图。Android 9.0 可以在截取屏幕截图后，直接共享、编辑，或者删除不喜欢的截图，而不需要像以前一样打开 Google 相册、找到要共享的屏幕截图、打开图像然后共享图像。 +由于我要撰写关于 Android 的文章，所以我会常常需要进行屏幕截图。而 Android 9.0 有一项我最喜欢的更新，就是分享屏幕截图。Android 9.0 可以在截取屏幕截图后，直接共享、编辑，或者删除不喜欢的截图，而不需要像以前一样打开 Google 相册、找到要共享的屏幕截图、打开图像然后共享图像。 + +如果你想分享屏幕截图，只需要在截图后等待弹出菜单，点击分享（图 6），从标准的 Android 分享菜单中分享即可。 ![Sharing ][11] -图 6：共享屏幕截图变得更加容易。 - -如果你想分享屏幕截图，只需要在截图后等待弹出菜单，点击分享（图 6），从标准的 Android 分享菜单中分享即可。 +*图 6：共享屏幕截图变得更加容易。* ### 更令人满意的 Android 体验 @@ -105,7 +97,7 @@ via: https://www.linux.com/learn/2018/10/overview-android-pie 作者：[Jack Wallen][a] 选题：[lujun9972][b] 译者：[HankChow](https://github.com/HankChow) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20181026 Ultimate Plumber - Writing Linux Pipes With Instant Live Preview.md b/published/201811/20181026 Ultimate Plumber - Writing Linux Pipes With Instant Live Preview.md similarity index 100% rename from published/20181026 Ultimate Plumber - Writing Linux Pipes With Instant Live Preview.md rename to published/201811/20181026 Ultimate Plumber - Writing Linux Pipes With Instant Live Preview.md diff --git a/published/20181027 Design faster web pages, part 3- Font and CSS tweaks.md b/published/201811/20181027 Design faster web pages, part 3- Font and CSS tweaks.md similarity index 100% rename from published/20181027 Design faster web pages, part 3- Font and CSS tweaks.md rename to published/201811/20181027 Design faster web pages, part 3- Font and CSS tweaks.md diff --git a/published/20181029 4 open source Android email clients.md b/published/201811/20181029 4 open source Android email clients.md similarity index 100% rename from published/20181029 4 open source Android email clients.md rename to published/201811/20181029 4 open source Android email clients.md diff --git a/published/20181029 Machine learning with Python- Essential hacks and tricks.md b/published/201811/20181029 Machine learning with Python- Essential hacks and tricks.md similarity index 100% rename from published/20181029 Machine learning with Python- Essential hacks and tricks.md rename to published/201811/20181029 Machine learning with Python- Essential hacks and tricks.md diff --git a/published/20181030 How Do We Find Out The Installed Packages Came From Which Repository.md b/published/201811/20181030 How Do We Find Out The Installed Packages Came From Which Repository.md similarity index 100% rename from published/20181030 How Do We Find Out The Installed Packages Came From Which Repository.md rename to published/201811/20181030 How Do We Find Out The Installed Packages Came From Which Repository.md diff --git a/published/20181030 How To Analyze And Explore The Contents Of Docker Images.md b/published/201811/20181030 How To Analyze And Explore The Contents Of Docker Images.md similarity index 100% rename from published/20181030 How To Analyze And Explore The Contents Of Docker Images.md rename to published/201811/20181030 How To Analyze And Explore The Contents Of Docker Images.md diff --git a/published/20181031 8 creepy commands that haunt the terminal - Opensource.com.md b/published/201811/20181031 8 creepy commands that haunt the terminal - Opensource.com.md similarity index 100% rename from published/20181031 8 creepy commands that haunt the terminal - Opensource.com.md rename to published/201811/20181031 8 creepy commands that haunt the terminal - Opensource.com.md diff --git a/published/20181101 KRS- A new tool for gathering Kubernetes resource statistics.md b/published/201811/20181101 KRS- A new tool for gathering Kubernetes resource statistics.md similarity index 100% rename from published/20181101 KRS- A new tool for gathering Kubernetes resource statistics.md rename to published/201811/20181101 KRS- A new tool for gathering Kubernetes resource statistics.md diff --git a/translated/tech/20181102 How To Create A Bootable Linux USB Drive From Windows OS 7,8 and 10.md b/published/201811/20181102 How To Create A Bootable Linux USB Drive From Windows OS 7,8 and 10.md similarity index 83% rename from translated/tech/20181102 How To Create A Bootable Linux USB Drive From Windows OS 7,8 and 10.md rename to published/201811/20181102 How To Create A Bootable Linux USB Drive From Windows OS 7,8 and 10.md index b51fbd8221..ef04dc33dd 100644 --- a/translated/tech/20181102 How To Create A Bootable Linux USB Drive From Windows OS 7,8 and 10.md +++ b/published/201811/20181102 How To Create A Bootable Linux USB Drive From Windows OS 7,8 and 10.md @@ -1,10 +1,11 @@ -如何从 Windows OS 7、8 和 10 创建可启动的 Linux USB 盘？ +如何从 Windows 7、8 和 10 创建可启动的 Linux USB 盘？ ====== + 如果你想了解 Linux，首先要做的是在你的系统上安装 Linux 系统。 它可以通过两种方式实现，使用 Virtualbox、VMWare 等虚拟化应用，或者在你的系统上安装 Linux。 -如果你倾向从 Windows 系统迁移到 Linux 系统或计划在备用机上安装 Linux 系统，那么你须为此创建可启动的 USB 盘。 +如果你倾向于从 Windows 系统迁移到 Linux 系统或计划在备用机上安装 Linux 系统，那么你须为此创建可启动的 USB 盘。 我们已经写过许多[在 Linux 上创建可启动 USB 盘][1] 的文章，如 [BootISO][2]、[Etcher][3] 和 [dd 命令][4]，但我们从来没有机会写一篇文章关于在 Windows 中创建 Linux 可启动 USB 盘的文章。不管怎样，我们今天有机会做这件事了。 @@ -22,29 +23,32 @@ 有许多程序可供使用，但我的首选是 [Universal USB Installer][6]，它使用起来非常简单。只需访问 Universal USB Installer 页面并下载该程序即可。 -### 步骤3：如何使用 Universal USB Installer 创建可启动的 Ubuntu ISO +### 步骤3：创建可启动的 Ubuntu ISO 这个程序在使用上不复杂。首先连接 USB 盘，然后点击下载的 Universal USB Installer。启动后，你可以看到类似于我们的界面。 + ![][8] - * **`步骤 1：`** 选择Ubuntu 系统。 - * **`步骤 2：`** 选择 Ubuntu ISO 下载位置。 - * **`步骤 3：`** 默认它选择的是 USB 盘，但是要验证一下，接着勾选格式化选项。 - - + * 步骤 1：选择 Ubuntu 系统。 + * 步骤 2：选择 Ubuntu ISO 下载位置。 + * 步骤 3：它默认选择的是 USB 盘，但是要验证一下，接着勾选格式化选项。 ![][9] -当你点击 `Create` 按钮时，它会弹出一个带有警告的窗口。不用担心，只需点击 `Yes` 继续进行此操作即可。 +当你点击 “Create” 按钮时，它会弹出一个带有警告的窗口。不用担心，只需点击 “Yes” 继续进行此操作即可。 + ![][10] USB 盘分区正在进行中。 + ![][11] -要等待一会儿才能完成。如你您想将它移至后台，你可以点击 `Background` 按钮。 +要等待一会儿才能完成。如你您想将它移至后台，你可以点击 “Background” 按钮。 + ![][12] 好了，完成了。 + ![][13] 现在你可以进行[安装 Ubuntu 系统][14]了。但是，它也提供了一个 live 模式，如果你想在安装之前尝试，那么可以使用它。 @@ -56,7 +60,7 @@ via: https://www.2daygeek.com/create-a-bootable-live-usb-drive-from-windows-usin 作者：[Prakash Subramanian][a] 选题：[lujun9972][b] 译者：[geekpi](https://github.com/geekpi) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20181105 CPod- An Open Source, Cross-platform Podcast App.md b/published/201811/20181105 CPod- An Open Source, Cross-platform Podcast App.md similarity index 100% rename from published/20181105 CPod- An Open Source, Cross-platform Podcast App.md rename to published/201811/20181105 CPod- An Open Source, Cross-platform Podcast App.md diff --git a/published/20181105 Commandline quick tips- How to locate a file.md b/published/201811/20181105 Commandline quick tips- How to locate a file.md similarity index 100% rename from published/20181105 Commandline quick tips- How to locate a file.md rename to published/201811/20181105 Commandline quick tips- How to locate a file.md diff --git a/published/20181105 Introducing pydbgen- A random dataframe-database table generator.md b/published/201811/20181105 Introducing pydbgen- A random dataframe-database table generator.md similarity index 100% rename from published/20181105 Introducing pydbgen- A random dataframe-database table generator.md rename to published/201811/20181105 Introducing pydbgen- A random dataframe-database table generator.md diff --git a/translated/tech/20181105 Revisiting the Unix philosophy in 2018.md b/published/201811/20181105 Revisiting the Unix philosophy in 2018.md similarity index 50% rename from translated/tech/20181105 Revisiting the Unix philosophy in 2018.md rename to published/201811/20181105 Revisiting the Unix philosophy in 2018.md index 09e6c7fa53..7c9931e601 100644 --- a/translated/tech/20181105 Revisiting the Unix philosophy in 2018.md +++ b/published/201811/20181105 Revisiting the Unix philosophy in 2018.md @@ -1,67 +1,65 @@ 2018 重温 Unix 哲学 ====== -在现代微服务环境中，构建小型，集中应用程序的旧策略又再一次流行了起来。 +> 在现代微服务环境中，构建小型、单一的应用程序的旧策略又再一次流行了起来。 + ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/brain_data.png?itok=RH6NA32X) -1984年，Rob Pike 和 Brian W 在 AT&T 贝尔实验室技术期刊上发表了名为 “[Unix 环境编程][1]” 的文章，其中他们使用 BSD 的 **cat -v** 例子来认证 Unix 哲学。简而言之，Unix 哲学是：构建小型，单一的应用程序——不管用什么语言——只做一件小而美的事情，用 **stdin** / **stdout** 进行通信，并通过管道进行连接。 +1984 年，Rob Pike 和 Brian W. Kernighan 在 AT&T 贝尔实验室技术期刊上发表了名为 “[Unix 环境编程][1]” 的文章，其中他们使用 BSD 的 `cat -v` 例子来认证 Unix 哲学。简而言之，Unix 哲学是：构建小型、单一的应用程序 —— 不管用什么语言 —— 只做一件小而美的事情，用 `stdin` / `stdout` 进行通信，并通过管道进行连接。 听起来是不是有点耳熟？ 是的，我也这么认为。这就是 James Lewis 和 Martin Fowler 给出的 [微服务的定义][2] 。 -> 简单来说，微服务架构的风格是将应用程序开发为一套单一，小型服务的方法，每个服务都运行在它的进程中，并用轻量级机制进行通信，通常是 HTTP 资源 API 。 +> 简单来说，微服务架构的风格是将单个 应用程序开发为一套小型服务的方法，每个服务都运行在它的进程中，并用轻量级机制进行通信，通常是 HTTP 资源 API 。 -虽然一个 *nix 程序或者是一个微服务本身可能非常局限甚至不是很有趣，但是当这些独立工作的单元组合在一起的时候就显示出了它们真正的好处和强大。 +虽然一个 *nix 程序或者是一个微服务本身可能非常局限甚至不是很有用，但是当这些独立工作的单元组合在一起的时候就显示出了它们真正的好处和强大。 ### *nix程序 vs 微服务 -下面的表格对比了 *nix 环境中的程序（例如 **cat** 或 **lsof**）与微服务环境中的程序。 +下面的表格对比了 *nix 环境中的程序（例如 `cat` 或 `lsof`）与微服务环境中的程序。 -| | *nix 程序 | 微服务 | -| ----------------------------------- | -------------------------- | ---------------------------------- | -| 执行单元 | 程序使用 `stdin/stdout` | 使用 HTTP 或 gRPC API | -| 数据流 | 管道 | ？ | -| 可配置和参数化 | 命令行参数 | | -| 环境变量和配置文件 | JSON/YAML 文档 | | -| 发现 | 包管理器， man， make | DNS, 环境变量, OpenAPI | +| | *nix 程序 | 微服务 | +| ------------- | ------------------------- | ----------------------- | +| 执行单元 | 程序使用 `stdin`/`stdout` | 使用 HTTP 或 gRPC API | +| 数据流 | 管道 | ？ | +| 可配置和参数化 | 命令行参数、环境变量和配置文件 | JSON/YAML 文档 | +| 发现 | 包管理器、man、make | DNS、环境变量、OpenAPI | 让我们详细的看看每一行。 #### 执行单元 -*nix 系统（像 Linux）中的执行单元是一个可执行的文件（二进制或者是脚本），理想情况下，它们从 `stdin` 读取输入并将输出写入 `stdout`。而微服务通过暴露一个或多个通信接口来提供服务，比如 HTTP 和 gRPC APIs。在这两种情况下，你都会发现无状态示例（本质上是纯函数行为）和有状态示例，除了输入之外，还有一些内部（持久）状态决定发生了什么。 +*nix 系统（如 Linux）中的执行单元是一个可执行的文件（二进制或者是脚本），理想情况下，它们从 `stdin` 读取输入并将输出写入 `stdout`。而微服务通过暴露一个或多个通信接口来提供服务，比如 HTTP 和 gRPC API。在这两种情况下，你都会发现无状态示例（本质上是纯函数行为）和有状态示例，除了输入之外，还有一些内部（持久）状态决定发生了什么。 #### 数据流 -传统的，*nix 程序能够通过管道进行通信。换名话说，我们要感谢 [Doug McIlroy][3]，你不需要创建临时文件来传递，而可以在每个进程之间处理无穷无尽的数据流。据我所知，除了 [2017 年做的基于 `Apache Kafka` 小实验][4]，没有什么能比得上管道化的微服务了。 +传统的，*nix 程序能够通过管道进行通信。换句话说，我们要感谢 [Doug McIlroy][3]，你不需要创建临时文件来传递，而可以在每个进程之间处理无穷无尽的数据流。据我所知，除了我在 [2017 年做的基于 Apache Kafka 小实验][4]，没有什么能比得上管道化的微服务了。 #### 可配置和参数化 -你是如何配置程序或者服务的，无论是永久性的服务还是即时的服务？是的，在 *nix 系统上，你通常有三种方法：命令行参数，环境变量，或全面化的配置文件。在微服务架构中，典型的做法是用 YAML ( 或者甚至是worse，JSON ) 文档，定制好一个服务的布局和配置以及依赖的组件和通信，存储，和运行时配置。例如 [ Kubernetes 资源定义][5]，[Nomad 工作规范][6]，或 [Docker 组件][7] 文档。这些可能参数化也可能不参数化；也就是说，除非你知道一些模板语言，像 Kubernetes 中的 [Helm][8]，否则你会发现你使用了很多 **sed -i** 这样的命令。 +你是如何配置程序或者服务的，无论是永久性的服务还是即时的服务？是的，在 *nix 系统上，你通常有三种方法：命令行参数、环境变量，或全面的配置文件。在微服务架构中，典型的做法是用 YAML（或者甚至是 JSON）文档，定制好一个服务的布局和配置以及依赖的组件和通信、存储和运行时配置。例如 [Kubernetes 资源定义][5]、[Nomad 工作规范][6] 或 [Docker 编排][7] 文档。这些可能参数化也可能不参数化；也就是说，除非你知道一些模板语言，像 Kubernetes 中的 [Helm][8]，否则你会发现你使用了很多 `sed -i` 这样的命令。 #### 发现 -你怎么知道有哪些程序和服务可用，以及如何使用它们？在 *nix 系统中通常都有一个包管理器和一个很好用的 man 页面；使用他们，应该能够回答你所有的问题。在微服务的设置中，在寻找一个服务的时候会相对更自动化一些。除了像 [Airbnb 的 SmartStack][9] 或 [Netflix 的 Eureka][10] 等可以定制以外，通常还有基于环境变量或基于 DNS 的[方法][11]，允许您动态的发现服务。同样重要的是，事实上 [OpenAPI][12] 为 HTTP API 提供了一套标准文档和设计模式，[gRPC][13] 为一些耦合性强的高性能项目也做了同样的事情。最后非常重要的一点是，考虑到开发人员的经验（DX），应该从写一份好的 [Makefiles][14] 开始，并以编写符合 [**风格**][15] 的文档结束。 +你怎么知道有哪些程序和服务可用，以及如何使用它们？在 *nix 系统中通常都有一个包管理器和一个很好用的 man 页面；使用它们，应该能够回答你所有的问题。在微服务的设置中，在寻找一个服务的时候会相对更自动化一些。除了像 [Airbnb 的 SmartStack][9] 或 [Netflix 的 Eureka][10] 等可以定制以外，通常还有基于环境变量或基于 DNS 的[方法][11]，允许您动态的发现服务。同样重要的是，事实上 [OpenAPI][12] 为 HTTP API 提供了一套标准文档和设计模式，[gRPC][13] 为一些耦合性强的高性能项目也做了同样的事情。最后非常重要的一点是，考虑到开发者经验（DX），应该从写一份好的 [Makefile][14] 开始，并以编写符合 [风格][15] 的文档结束。 ### 优点和缺点 -*nix 系统和微服务都提供了许多挑战和机遇 +*nix 系统和微服务都提供了许多挑战和机遇。 #### 模块性 -设计一个简洁，有清晰的目的并且能够很好的和其它模块配合是很困难的。甚至是在不同版本中实现并引入相应的异常处理流程都很困难的。在微服务中，这意味着重试逻辑和超时机制，或者将这些功能外包到服务网格（ service mesh ）是不是一个更好的选择呢？这确实比较难，可如果你做好了，那它的可重用性是巨大的。 +要设计一个简洁、有清晰的目的，并且能够很好地和其它模块配合的某个东西是很困难的。甚至是在不同版本中实现并引入相应的异常处理流程都很困难的。在微服务中，这意味着重试逻辑和超时机制，或者将这些功能外包到服务网格service mesh是不是一个更好的选择呢？这确实比较难，可如果你做好了，那它的可重用性是巨大的。 -#### Observability +#### 可观测性 -#### 预测 - -在一个巨型（2018年）或是一个试图做任何事情的大型程序（1984）年，当事情开始变坏的时候，应当能够直接的找到问题的根源。但是在一个 +在一个独石monolith（2018 年）或是一个试图做任何事情的大型程序（1984 年），当情况恶化的时候，应当能够直接的找到问题的根源。但是在一个 ``` yes | tr \\n x | head -c 450m | grep n ``` -或者在一个微服务设置中请求一个路径，例如，涉及20个服务，你怎么弄清楚是哪个服务的问题？幸运的是，我们有很多标准，特别是 [OpenCensus][16] 和 [OpenTracing][17]。如果您希望转向微服务，可预测性仍然可能是最大的问题。 +或者在一个微服务设置中请求一个路径，例如，涉及 20 个服务，你怎么弄清楚是哪个服务的问题？幸运的是，我们有很多标准，特别是 [OpenCensus][16] 和 [OpenTracing][17]。如果您希望转向微服务，可预测性仍然可能是最大的问题。 #### 全局状态 @@ -77,8 +75,8 @@ via: https://opensource.com/article/18/11/revisiting-unix-philosophy-2018 作者：[Michael Hausenblas][a] 选题：[lujun9972][b] -译者：[Jamkr](https://github.com/Jamkr) -校对：[校对者ID](https://github.com/校对者ID) +译者：[Jamskr](https://github.com/Jamskr) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/20181105 Some Good Alternatives To ‘du- Command.md b/published/201811/20181105 Some Good Alternatives To ‘du- Command.md similarity index 100% rename from published/20181105 Some Good Alternatives To ‘du- Command.md rename to published/201811/20181105 Some Good Alternatives To ‘du- Command.md diff --git a/published/20181107 Gitbase- Exploring git repos with SQL.md b/published/201811/20181107 Gitbase- Exploring git repos with SQL.md similarity index 100% rename from published/20181107 Gitbase- Exploring git repos with SQL.md rename to published/201811/20181107 Gitbase- Exploring git repos with SQL.md diff --git a/published/20181107 How To Find The Execution Time Of A Command Or Process In Linux.md b/published/201811/20181107 How To Find The Execution Time Of A Command Or Process In Linux.md similarity index 100% rename from published/20181107 How To Find The Execution Time Of A Command Or Process In Linux.md rename to published/201811/20181107 How To Find The Execution Time Of A Command Or Process In Linux.md diff --git a/published/20181108 Choosing a printer for Linux.md b/published/201811/20181108 Choosing a printer for Linux.md similarity index 100% rename from published/20181108 Choosing a printer for Linux.md rename to published/201811/20181108 Choosing a printer for Linux.md diff --git a/published/20181108 The Difference Between more, less And most Commands.md b/published/201811/20181108 The Difference Between more, less And most Commands.md similarity index 100% rename from published/20181108 The Difference Between more, less And most Commands.md rename to published/201811/20181108 The Difference Between more, less And most Commands.md diff --git a/published/20181109 7 reasons I love open source.md b/published/201811/20181109 7 reasons I love open source.md similarity index 100% rename from published/20181109 7 reasons I love open source.md rename to published/201811/20181109 7 reasons I love open source.md diff --git a/published/20181113 4 tips for learning Golang.md b/published/201811/20181113 4 tips for learning Golang.md similarity index 100% rename from published/20181113 4 tips for learning Golang.md rename to published/201811/20181113 4 tips for learning Golang.md diff --git a/translated/tech/20181113 The alias And unalias Commands Explained With Examples.md b/published/201811/20181113 The alias And unalias Commands Explained With Examples.md similarity index 58% rename from translated/tech/20181113 The alias And unalias Commands Explained With Examples.md rename to published/201811/20181113 The alias And unalias Commands Explained With Examples.md index da859b2d29..1448918a1e 100644 --- a/translated/tech/20181113 The alias And unalias Commands Explained With Examples.md +++ b/published/201811/20181113 The alias And unalias Commands Explained With Examples.md @@ -1,22 +1,23 @@ 举例说明 alias 和 unalias 命令 ====== + ![](https://www.ostechnix.com/wp-content/uploads/2018/11/alias-command-720x340.png) -如果不是一个深度的命令行用户的话，你可能已经忘记了这些复杂且冗长的 Linux 命令了。当然，有很多方法可以让你 [**回想起遗忘的命令**][1]。你可以简单的 [**保存常用的命令**][2] 然后按需使用。也可以在终端里 [**标记重要的命令**][3]，然后在任何时候你想要的时间使用它们。而且，Linux 有一个内建命令 **history** 可以帮助你记忆这些命令。另外一个最简便的方式就是为这些命令创建一个别名。你可以为任何经常重复调用的常用命令创建别名，而不仅仅是长命令。通过这种方法，你不必再过多地记忆这些命令。这篇文章中，我们将会在 Linux 环境下举例说明 **alias** 和 **unalias** 命令。 +如果不是一个命令行重度用户的话，过了一段时间之后，你就可能已经忘记了这些复杂且冗长的 Linux 命令了。当然，有很多方法可以让你 [回想起遗忘的命令][1]。你可以简单的 [保存常用的命令][2] 然后按需使用。也可以在终端里 [标记重要的命令][3]，然后在任何时候你想要的时间使用它们。而且，Linux 有一个内建命令 `history` 可以帮助你记忆这些命令。另外一个记住这些如此长的命令的简便方式就是为这些命令创建一个别名。你可以为任何经常重复调用的常用命令创建别名，而不仅仅是长命令。通过这种方法，你不必再过多地记忆这些命令。这篇文章中，我们将会在 Linux 环境下举例说明 `alias` 和 `unalias` 命令。 ### alias 命令 -**alias** 使用一个用户自定义的字符串来代替一个或者一串命令（包括多个选项，参数）。这个字符串可以是一个简单的名字或者缩写，不管这个命令原来多么复杂。alias 命令已经预装在 shell（包括 BASH，Csh，Ksh 和 Zsh 等） 当中。 +`alias` 使用一个用户自定义的字符串来代替一个或者一串命令（包括多个选项、参数）。这个字符串可以是一个简单的名字或者缩写，不管这个命令原来多么复杂。`alias` 命令已经预装在 shell（包括 BASH、Csh、Ksh 和 Zsh 等） 当中。 - -alias 的通用语法是： +`alias` 的通用语法是： ``` alias [alias-name[=string]...] ``` + 接下来看几个例子。 -**列出别名** +#### 列出别名 可能在你的系统中已经设置了一些别名。有些应用在你安装它们的时候可能已经自动创建了别名。要查看已经存在的别名，运行： @@ -40,7 +41,7 @@ alias pbpaste='xclip -selection clipboard -o' alias update='newsbeuter -r && sudo pacman -Syu' ``` -**创建一个新的别名** +#### 创建一个新的别名 像我之前说的，你不必去记忆这些又臭又长的命令。你甚至不必一遍一遍的运行长命令。只需要为这些命令创建一个简单易懂的别名，然后在任何你想使用的时候运行这些别名就可以了。这种方式会让你爱上命令行。 @@ -54,21 +55,22 @@ $ du -h --max-depth=1 | sort -hr $ alias du='du -h --max-depth=1 | sort -hr' ``` -这里的 **du** 就是这条命令的别名。这个别名可以被设置为任何名字，主要便于记忆和区别。 +这里的 `du` 就是这条命令的别名。这个别名可以被设置为任何名字，主要便于记忆和区别。 在创建一个别名的时候，使用单引号或者双引号都是可以的。这两种方法最后的结果没有任何区别。 -现在你可以运行这个别名（例如我们这个例子中的 **du** ）。它和上面的原命令将会产生相同的结果。 +现在你可以运行这个别名（例如我们这个例子中的 `du` ）。它和上面的原命令将会产生相同的结果。 这个别名仅限于当前 shell 会话中。一旦你退出了当前 shell 会话，别名也就失效了。为了让这些别名长久有效，你需要把它们添加到你 shell 的配置文件当中。 -BASH，编辑 **~/.bashrc** 文件： +BASH，编辑 `~/.bashrc` 文件： ``` $ nano ~/.bashrc ``` 一行添加一个别名： + ![](https://www.ostechnix.com/wp-content/uploads/2018/11/alias.png) 保存并退出这个文件。然后运行以下命令更新修改： @@ -79,21 +81,20 @@ $ source ~/.bashrc 现在，这些别名在所有会话中都可以永久使用了。 -ZSH，你需要添加这些别名到 **~/.zshrc**文件中。 -Fish，跟上面的类似，添加这些别名到 **~/.config/fish/config.fish** 文件中。 +ZSH，你需要添加这些别名到 `~/.zshrc`文件中。Fish，跟上面的类似，添加这些别名到 `~/.config/fish/config.fish` 文件中。 -**查看某个特定的命令别名** +#### 查看某个特定的命令别名 -像我上面提到的，你可以使用 ‘alias’ 命令列出你系统中所有的别名。如果你想查看跟给定的别名有关的命令，例如 ‘du’，只需要运行： +像我上面提到的，你可以使用 `alias` 命令列出你系统中所有的别名。如果你想查看跟给定的别名有关的命令，例如 `du`，只需要运行： ``` $ alias du alias du='du -h --max-depth=1 | sort -hr' ``` -像你看到的那样，上面的命令可以显示与单词 ‘du’ 有关的命令。 +像你看到的那样，上面的命令可以显示与单词 `du` 有关的命令。 -关于 别名 命令更多的细节，参阅 man 手册页： +关于 `alias` 命令更多的细节，参阅 man 手册页： ``` $ man alias @@ -101,23 +102,23 @@ $ man alias ### unalias 命令 -跟它的名字说的一样，**unalias** 命令可以很轻松地从你的系统当中移除别名。unalias 命令的通用语法是： +跟它的名字说的一样，`unalias` 命令可以很轻松地从你的系统当中移除别名。`unalias` 命令的通用语法是： ``` unalias ``` -要移除命令的别名，像我们之前创建的 ‘du’，只需要运行： +要移除命令的别名，像我们之前创建的 `du`，只需要运行： ``` $ unalias du ``` -unalias 命令不仅会从当前会话中移除别名，也会从你的 shell 配置文件中永久地移除别名。 +`unalias` 命令不仅会从当前会话中移除别名，也会从你的 shell 配置文件中永久地移除别名。 还有一种移除别名的方法，是创建具有相同名称的新别名。 -要从当前会话中移除所有的别名，使用 **-a** 选项： +要从当前会话中移除所有的别名，使用 `-a` 选项： ``` $ unalias -a @@ -144,7 +145,7 @@ via: https://www.ostechnix.com/the-alias-and-unalias-commands-explained-with-exa 作者：[SK][a] 选题：[lujun9972][b] 译者：[dianbanjiu](https://github.com/dianbanjiu) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/translated/talk/20181113 What you need to know about the GPL Cooperation Commitment.md b/published/201811/20181113 What you need to know about the GPL Cooperation Commitment.md similarity index 77% rename from translated/talk/20181113 What you need to know about the GPL Cooperation Commitment.md rename to published/201811/20181113 What you need to know about the GPL Cooperation Commitment.md index 0db4bf2272..2218dfcd2c 100644 --- a/translated/talk/20181113 What you need to know about the GPL Cooperation Commitment.md +++ b/published/201811/20181113 What you need to know about the GPL Cooperation Commitment.md @@ -1,21 +1,21 @@ GPL 合作承诺的发展历程 ====== -GPL 合作承诺消除了开发者对许可证失效的顾虑，从而达到促进技术创新的目的。 +> GPL 合作承诺GPL Cooperation Commitment消除了开发者对许可证失效的顾虑，从而达到促进技术创新的目的。 ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/OSDC_Law_balance_open_source.png?itok=5c4JhuEY) -假如没有任何顾虑，技术创新和发展将会让世界发生天翻地覆的改变。[GPL 合作承诺][1]就这样应运而生，只为通过公平、一致、可预测的许可证来让科技创新无后顾之忧。 +假如能免于顾虑，技术创新和发展将会让世界发生天翻地覆的改变。[GPL 合作承诺][1]GPL Cooperation Commitment就这样应运而生，只为通过公平、一致、可预测的许可证来让科技创新无后顾之忧。 -去年，我曾经写过一篇文章，讨论了许可证对开源软件下游用户的影响。在进行研究的时候，我就发现许可证的约束力并不强，而且很多情况下是不可预测的。因此，我在文章中提出了一个能使开源许可证具有一致性和可预测性的潜在解决方案。但我只考虑到了诸如通过法律系统立法的传统方法。 +去年，我曾经写过一篇文章，讨论了许可证对开源软件下游用户的影响。在进行研究的时候，我就发现许可证的约束力并不强，而且很多情况下是不可预测的。因此，我在文章中提出了一个能使开源许可证具有一致性和可预测性的潜在解决方案。但我只考虑到了诸如通过法律系统立法的“传统”方法。 2017 年 11 月，RedHat、IBM、Google 和 Facebook 提出了这种我从未考虑过的非传统的解决方案：GPL 合作承诺。GPL 合作承诺规定了 GPL 公平一致执行的方式。我认为，GPL 合作承诺之所以有这么深刻的意义，有以下两个原因：一是许可证的公平性和一致性对于开源社区的发展来说至关重要，二是法律对不可预测性并不容忍。 -### 了解 GPL +### 了解 GPL -要了解 GPL 合作承诺，首先要了解什么是 GPL。GPL 是 [GNU 通用许可证][2]GNU General Public License的缩写，它是一个公共版权的开源许可证，这就意味着开源软件的分发者必须向下游用户公开源代码。GPL 还禁止对下游用户作出限制，要求个人用户不得拒绝他人对开源软件的使用自由、研究自由、共享自由和改进自由。GPL 规定，只要下游用户满足了许可证的要求和条件，就可以使用该许可证。如果被许可人出现了不符合许可证的情况，则视为违规。 +要了解 GPL 合作承诺，首先要了解什么是 GPL。GPL 是 [GNU 通用许可证][2]GNU General Public License的缩写，它是一个公共版权的开源许可证，这就意味着开源软件的分发者必须向下游用户公开源代码。GPL 还禁止对下游的使用作出限制，要求个人用户不得拒绝他人对开源软件的使用自由、研究自由、共享自由和改进自由。GPL 规定，只要下游用户满足了许可证的要求和条件，就可以使用该许可证。如果被许可人出现了不符合许可证的情况，则视为违规。 -按照第二版 GPL（GPLv2）的描述，许可证会在任何违规的情况下自动终止，这就导致了部分开发者对 GPL 有所抗拒。而在第三版 GPL（GPLv3）中则引入了“[治愈条款cure provision][3]”，这一条款规定，被许可人可以在 30 天内对违反 GPL 的行为进行改正，如果在这个缓冲期内改正完成，许可证就不会被终止。 +按照第二版 GPL（GPLv2）的描述，许可证会在任何违规的情况下自动终止，这就导致了部分开发者对 GPL 有所抗拒。而在第三版 GPL（GPLv3）中则引入了“[治愈条款][3]cure provision”，这一条款规定，被许可人可以在 30 天内对违反 GPL 的行为进行改正，如果在这个缓冲期内改正完成，许可证就不会被终止。 这一规定消除了许可证被无故终止的顾虑，从而让软件的开发者和用户专注于开发和创新。 @@ -23,10 +23,9 @@ GPL 合作承诺消除了开发者对许可证失效的顾虑，从而达到促 GPL 合作承诺将 GPLv3 的治愈条款应用于使用 GPLv2 的软件上，让使用 GPLv2 许可证的开发者避免许可证无故终止的窘境，并与 GPLv3 许可证保持一致。 - 很多软件开发者都希望正确合规地做好一件事情，但有时候却不了解具体的实施细节。因此，GPL 合作承诺的重要性就在于能够对软件开发者们做出一些引导，让他们避免因一些简单的错误导致许可证违规终止。 -Linux 基金会技术顾问委员会在 2017 年宣布，Linux 内核项目将会[采用 GPLv3 的治愈条款][4]。在 GPL 合作承诺的推动下，很多大型科技公司和个人开发者都承诺，会将自己的开源软件和 Linux 内核贡献在 30 天缓冲期内从 GPLv2 或 LGPLv2.1 扩展到 GPLv3。 +Linux 基金会技术顾问委员会在 2017 年宣布，Linux 内核项目将会[采用 GPLv3 的治愈条款][4]。在 GPL 合作承诺的推动下，很多大型科技公司和个人开发者都做出了相同的承诺，会将该条款扩展应用于他们采用 GPLv2（或 LGPLv2.1）许可证的所有软件，而不仅仅是对 Linux 内核的贡献。 GPL 合作承诺的广泛采用将会对开源社区产生非常积极的影响。如果更多的公司和个人开始采用 GPL 合作承诺，就能让大量正在使用 GPLv2 或 LGPLv2.1 许可证的软件以更公平和更可预测的形式履行许可证中的条款。 @@ -41,7 +40,7 @@ via: https://opensource.com/article/18/11/gpl-cooperation-commitment 作者：[Brooke Driver][a] 选题：[lujun9972][b] 译者：[HankChow](https://github.com/HankChow) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/translated/tech/20181114 ProtectedText - A Free Encrypted Notepad To Save Your Notes Online.md b/published/201811/20181114 ProtectedText - A Free Encrypted Notepad To Save Your Notes Online.md similarity index 84% rename from translated/tech/20181114 ProtectedText - A Free Encrypted Notepad To Save Your Notes Online.md rename to published/201811/20181114 ProtectedText - A Free Encrypted Notepad To Save Your Notes Online.md index 60b53cca9a..99a92d917b 100644 --- a/translated/tech/20181114 ProtectedText - A Free Encrypted Notepad To Save Your Notes Online.md +++ b/published/201811/20181114 ProtectedText - A Free Encrypted Notepad To Save Your Notes Online.md @@ -1,18 +1,19 @@ ProtectedText：一个免费的在线加密笔记 ====== + ![](https://www.ostechnix.com/wp-content/uploads/2018/11/protected-text-720x340.png) -记录笔记是我们每个人必备的重要技能，它可以帮助我们把自己听到、读到、学到的内容长期地保留下来，也有很多的应用和工具都能让我们更好地记录笔记。下面我要介绍一个叫做 **ProtectedText** 的应用，一个可以将你的笔记在线上保存起来的免费的加密笔记。它是一个免费的 web 服务，在上面记录文本以后，它将会对文本进行加密，只需要一台支持连接到互联网并且拥有 web 浏览器的设备，就可以访问到记录的内容。 +记录笔记是我们每个人必备的重要技能，它可以帮助我们把自己听到、读到、学到的内容长期地保留下来，也有很多的应用和工具都能让我们更好地记录笔记。下面我要介绍一个叫做 **ProtectedText** 的应用，这是一个可以将你的笔记在线上保存起来的免费的加密笔记。它是一个免费的 web 服务，在上面记录文本以后，它将会对文本进行加密，只需要一台支持连接到互联网并且拥有 web 浏览器的设备，就可以访问到记录的内容。 ProtectedText 不会向你询问任何个人信息，也不会保存任何密码，没有广告，没有 Cookies，更没有用户跟踪和注册流程。除了拥有密码能够解密文本的人，任何人都无法查看到笔记的内容。而且，使用前不需要在网站上注册账号，写完笔记之后，直接关闭浏览器，你的笔记也就保存好了。 ### 在加密笔记本上记录笔记 -访问 这个链接，就可以打开 ProtectedText 页面了。这个时候你将进入网站主页，接下来需要在页面上的输入框输入一个你想用的名称，或者在地址栏后面直接加上想用的名称。这个名称是一个自定义的名称（例如 ），是你查看自己保存的笔记的专有入口。 +访问 这个链接，就可以打开 ProtectedText 页面了（LCTT 译注：如果访问不了，你知道的）。这个时候你将进入网站主页，接下来需要在页面上的输入框输入一个你想用的名称，或者在地址栏后面直接加上想用的名称。这个名称是一个自定义的名称（例如 ），是你查看自己保存的笔记的专有入口。 ![](https://www.ostechnix.com/wp-content/uploads/2018/11/Protected-Text-1.png) -如果你选用的名称还没有被占用，你就会看到下图中的提示信息。点击“Create”键就可以创建你的个人笔记页了。 +如果你选用的名称还没有被占用，你就会看到下图中的提示信息。点击 “Create” 键就可以创建你的个人笔记页了。 ![](https://www.ostechnix.com/wp-content/uploads/2018/11/Protected-Text-2.png) @@ -20,11 +21,11 @@ ProtectedText 不会向你询问任何个人信息，也不会保存任何密码 ProtectedText 使用 AES 算法对你的笔记内容进行加密和解密，而计算散列则使用了 SHA512 算法。 -笔记记录完毕以后，点击顶部的“Save”键保存。 +笔记记录完毕以后，点击顶部的 “Save” 键保存。 ![](https://www.ostechnix.com/wp-content/uploads/2018/11/Protected-Text-3.png) -按下保存键之后，ProtectedText 会提示你输入密码以加密你的笔记内容。按照它的要求输入两次密码，然后点击“Save”键。 +按下保存键之后，ProtectedText 会提示你输入密码以加密你的笔记内容。按照它的要求输入两次密码，然后点击 “Save” 键。 ![](https://www.ostechnix.com/wp-content/uploads/2018/11/Protected-Text-4.png) @@ -45,15 +46,12 @@ ProtectedText 还有配套的 [Android 应用][6] 可以让你在移动设备上 * 存储的内容没有到期时间，只要你愿意，笔记内容可以一直保存在服务器上 * 可以让你的数据限制为私有或公开开放 - - **缺点** * 尽管客户端代码是公开的，但服务端代码并没有公开，因此你无法自行搭建一个类似的服务。如果你不信任这个网站，请不要使用。 * 由于网站不存储你的任何个人信息，包括你的密码，因此如果你丢失了密码，数据将永远无法恢复。网站方还声称他们并不清楚谁拥有了哪些数据，所以一定要牢记密码。 - 如果你想通过一种简单的方式将笔记保存到线上，并且需要在不需要安装任何工具的情况下访问，那么 ProtectedText 会是一个好的选择。如果你还知道其它类似的应用程序，欢迎在评论区留言！ @@ -65,7 +63,7 @@ via: https://www.ostechnix.com/protectedtext-a-free-encrypted-notepad-to-save-yo 作者：[SK][a] 选题：[lujun9972][b] 译者：[HankChow](https://github.com/HankChow) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/translated/tech/20181115 How to install a device driver on Linux.md b/published/201811/20181115 How to install a device driver on Linux.md similarity index 69% rename from translated/tech/20181115 How to install a device driver on Linux.md rename to published/201811/20181115 How to install a device driver on Linux.md index e078e05c0c..bd1c3fd353 100644 --- a/translated/tech/20181115 How to install a device driver on Linux.md +++ b/published/201811/20181115 How to install a device driver on Linux.md @@ -1,38 +1,40 @@ 如何在 Linux 上安装设备驱动程序 ====== -学习 Linux 设备驱动如何工作，并知道如何使用它们。 + +> 学习 Linux 设备驱动如何工作，并知道如何使用它们。 ![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/car-penguin-drive-linux-yellow.png?itok=twWGlYAc) -对于一个熟悉 Windows 或者 MacOS 的人，想要切换到 Linux，它们都会面临一个艰巨的问题就是怎么安装和配置设备驱动。这是可以理解的，因为 Windows 和 MacOS 都有一套机制把这个过程做得非常的友好。比如说，当你插入一个新的硬件设备， Windows 能够自动检测并会弹出一个窗口询问你是否要继续驱动程序。你也可以从网络上下载驱动程序，仅仅需要双击解压或者是通过设备管理器导入驱动程序即可。 +对于一个熟悉 Windows 或者 MacOS 的人，想要切换到 Linux，它们都会面临一个艰巨的问题就是怎么安装和配置设备驱动。这是可以理解的，因为 Windows 和 MacOS 都有一套机制把这个过程做得非常的友好。比如说，当你插入一个新的硬件设备， Windows 能够自动检测并会弹出一个窗口询问你是否要继续驱动程序的安装。你也可以从网络上下载驱动程序，仅仅需要双击解压或者是通过设备管理器导入驱动程序即可。 而这在 Linux 操作系统上并非这么简单。第一个原因是， Linux 是一个开源的操作系统，所以有 [数百种 Linux 发行版的变体][1]。也就是说不可能做一个指南来适应所有的 Linux 发行版。因为每种 Linux 安装驱动程序的过程都有差异。 -第二，大多数默认的 Linux 驱动程序也都是开源的，并被集成到了系统中，这使得安装一些并未包含的驱动程序变得非常复杂，即使已经可以检测大多数的硬件设备。第三，不同发行版的许可也有差异。例如，[Fedora 禁止事项][2] 禁止包含专有的，受法律保护，或者是违反美国法律的驱动程序。而 Ubuntu 则让用户[避免使用受法律保护或闭源的硬件设备][3]。 +第二，大多数默认的 Linux 驱动程序也都是开源的，并被集成到了系统中，这使得安装一些并未包含的驱动程序变得非常复杂，即使已经可以检测大多数的硬件设备。第三，不同发行版的许可也有差异。例如，[Fedora 禁止事项][2] 禁止包含专有的、受法律保护，或者是违反美国法律的驱动程序。而 Ubuntu 则让用户[避免使用受法律保护或闭源的硬件设备][3]。 -为了更好的学习 Linux 驱动程序是如何工作的，我建议阅读 Linux 设备驱动程序一书中的 [设备驱动程序简介][4]。 +为了更好的学习 Linux 驱动程序是如何工作的，我建议阅读 《Linux 设备驱动程序》一书中的 [设备驱动程序简介][4]。 ### 两种方式来寻找驱动程序 -#### 1\. 用户界面 +#### 1、 用户界面 如果是一个刚从 Windows 或 MacOS 转过来的 Linux 新手，那你会很高兴知道 Linux 也提供了一个通过向导式的程序来查看驱动程序是否可用的方法。 Ubuntu 提供了一个 [附加驱动程序][5] 选项。其它的 Linux 发行版也提供了帮助程序，像 [GNOME 的包管理器][6]，你可以使用它来检查驱动程序是否可用。 -#### 2\. 命令行 +#### 2、 命令行 -如果你通过漂亮的用户界面找到驱动程序，那又该怎么办呢？或许你只能通过没有任何图形界面的 shell？甚至你可以使用控制台来展现你的技能。你有两个选择： +如果你通过漂亮的用户界面没有找到驱动程序，那又该怎么办呢？或许你只能通过没有任何图形界面的 shell？甚至你可以使用控制台来展现你的技能。你有两个选择： - A. **通过一个仓库** -这和 MacOS 中的 [**homebrew**][7] 命令行很像。通过使用 `yum` , `dnf` , `apt-get` , 等等。你基本可以通过添加仓库，并更新包缓存。 +1. **通过一个仓库** - B. **下载, 编译, 然后自己构建** -这通常包括直接从网络，或通过 `wget` 命令下载源码包，然后运行配置和编译、安装。这超出了本文的范围，但是你可以在网络上找到很多在线指南，如果你选择的是这条路的话。 + 这和 MacOS 中的 [homebrew][7] 命令行很像。通过使用 `yum`、 `dnf`、`apt-get` 等等。你基本可以通过添加仓库，并更新包缓存。 +2. **下载、编译，然后自己构建** + + 这通常包括直接从网络，或通过 `wget` 命令下载源码包，然后运行配置和编译、安装。这超出了本文的范围，但是你可以在网络上找到很多在线指南，如果你选择的是这条路的话。 ### 检查是否已经安装了这个驱动程序 在进一步学习安装 Linux 驱动程序之前，让我们来学习几条命令，用来检测驱动程序是否已经在你的系统上可用。 -[`lspci`][8] 命令显示了系统上所有 PCI 总线和设备驱动程序的详细信息。 +[lspci][8] 命令显示了系统上所有 PCI 总线和设备驱动程序的详细信息。 ``` $ lscpci @@ -46,13 +48,13 @@ $ lscpci | grep SOME_DRIVER_KEYWORD 例如，你可以使用 `lspci | grep SAMSUNG` 命令，如果你想知道是否安装过三星的驱动。 -[`dmesg`][9] 命令显示了所有内核识别的驱动程序。 +[dmesg][9] 命令显示了所有内核识别的驱动程序。 ``` $ dmesg ``` -或配合 `grep` 使用 +或配合 `grep` 使用： ``` $ dmesg | grep SOME_DRIVER_KEYWORD @@ -72,7 +74,7 @@ $ /sbin/lsmod $ find /lib/modules ``` -小贴士：和`lspci` 或 `dmesg` 一样，通过在上面的命令后面加上 `| grep` 来过滤结果。 +技巧：和 `lspci` 或 `dmesg` 一样，通过在上面的命令后面加上 `| grep` 来过滤结果。 如果一个驱动程序已经被识别到了，但是通过 `lscpi` 或 `dmesg` 并没有找到，这意味着驱动程序已经存在于硬盘上，但是并没有加载到内核中，这种情况，你可以通过 `modprobe` 命令来加载这个模块。 @@ -84,9 +86,9 @@ $ sudo modprobe MODULE_NAME ### 添加仓库并安装 -可以通过 `yum` , `dnf` , 和 `apt-get` 几种不同的方式来添加一个仓库；一个个介绍完它们并不在本文的范围。简单一点来说，这个示例将会使用 `apt-get` ，但是这个命令和其它的几个都是很类似的。 +可以通过 `yum`、`dnf` 和 `apt-get` 几种不同的方式来添加一个仓库；一个个介绍完它们并不在本文的范围。简单一点来说，这个示例将会使用 `apt-get` ，但是这个命令和其它的几个都是很类似的。 -**1\. 删除存在的仓库，如果它存在.** +#### 1、删除存在的仓库，如果它存在 ``` $ sudo apt-get purge NAME_OF_DRIVER* @@ -94,7 +96,7 @@ $ sudo apt-get purge NAME_OF_DRIVER* 其中 `NAME_OF_DRIVER` 是你的驱动程序的可能的名称。你还可以将模式匹配加到正则表达式中来进一步过滤。 -**2\. 将仓库加入到仓库表中，这应该在驱动程序指南中有指定** +#### 2、将仓库加入到仓库表中，这应该在驱动程序指南中有指定 ``` $ sudo add-apt-repository REPOLIST_OF_DRIVER @@ -102,23 +104,22 @@ $ sudo add-apt-repository REPOLIST_OF_DRIVER 其中 `REPOLIST_OF_DRIVER` 应该从驱动文档中有指定（例如：`epel-list`）。 -**3\. 更新仓库列表。** +#### 3、更新仓库列表 ``` $ sudo apt-get update ``` -**4\. 安装驱动程序。** +#### 4、安装驱动程序 ``` $ sudo apt-get install NAME_OF_DRIVER ``` -**5\. 检查安装状态.** +#### 5、检查安装状态 像上面说的一样，通过 `lscpi` 命令来检查驱动程序是否已经安装成功。 - -------------------------------------------------------------------------------- via: https://opensource.com/article/18/11/how-install-device-driver-linux @@ -126,7 +127,7 @@ via: https://opensource.com/article/18/11/how-install-device-driver-linux 作者：[Bryant Son][a] 选题：[lujun9972][b] 译者：[Jamskr](https://github.com/Jamskr) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/201811/20181116 Akash Angle- How do you Fedora.md b/published/201811/20181116 Akash Angle- How do you Fedora.md new file mode 100644 index 0000000000..ccd764f8aa --- /dev/null +++ b/published/201811/20181116 Akash Angle- How do you Fedora.md @@ -0,0 +1,62 @@ +Akash Angle：你如何使用 Fedora？ +====== + +![](https://fedoramagazine.org/wp-content/uploads/2018/11/akash-angle-816x345.jpg) + +我们最近采访了Akash Angle 来了解他如何使用 Fedora。这是 Fedora Magazine 上 Fedora [系列的一部分][1]。该系列介绍 Fedora 用户以及他们如何使用 Fedora 完成工作。请通过[反馈表单][2]与我们联系表达你对成为受访者的兴趣。 + +### Akash Angle 是谁？ + +Akash 是一位不久前抛弃 Windows 的 Linux 用户。作为一名过去 9 年的狂热 Fedora 用户，他已经尝试了几乎所有的 Fedora 定制版和桌面环境来完成他的日常任务。是一位校友给他介绍了 Fedora。 + +### 使用什么硬件？ + +Akash 在工作时使用联想 B490。它配备了英特尔酷睿 i3-3310 处理器和 240GB 金士顿 SSD。Akash 说：“这台笔记本电脑非常适合一些日常任务，如上网、写博客，以及一些照片编辑和视频编辑。虽然不是专业的笔记本电脑，而且规格并不是那么高端，但它完美地完成了工作。“ + +他使用一个入门级的罗技无线鼠标，并希望能有一个机械键盘。他的 PC 是一台定制桌面电脑，拥有最新的第 7 代 Intel i5 7400 处理器和 8GB Corsair Vengeance 内存。 + +![][3] + +### 使用什么软件？ + +Akash 是 GNOME 3 桌面环境的粉丝。他喜欢该操作系统为完成基本任务而加入的华丽功能。 + +出于实际原因，他更喜欢全新安来升级到最新 Fedora 版本。他认为 Fedora 29 可以说是最好的工作站。Akash 说这种说法得到了各种科技传播网站和开源新闻网站评论的支持。 + +为了播放视频，他的首选是打包为 [Flatpak][4] 的 VLC 视频播放器 ，它提供了最新的稳定版本。当 Akash 想截图时，他的终极工具是 [Shutter，Magazine 曾介绍过][5]。对于图形处理，GIMP 是他不能离开的工具。 + +Google Chrome 稳定版和开发版是他最常用的网络浏览器。他还使用 Chromium 和 Firefox 的默认版本，有时甚至会使用 Opera。 + +由于他是一名资深用户，所以 Akash 其余时候都使用终端。GNOME Terminal 是他使用的一个终端。 + +#### 最喜欢的壁纸 + +他最喜欢的壁纸之一是下面最初来自 Fedora 16 的壁纸： + +![][6] + +这是他目前在 Fedora 29 工作站上使用的壁纸之一： + +![][7] + + +-------------------------------------------------------------------------------- + +via: https://fedoramagazine.org/akash-angle-how-do-you-fedora/ + +作者：[Adam Šamalík][a] +选题：[lujun9972][b] +译者：[geekpi](https://github.com/geekpi) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://fedoramagazine.org/author/asamalik/ +[b]: https://github.com/lujun9972 +[1]: https://fedoramagazine.org/tag/how-do-you-fedora/ +[2]: https://fedoramagazine.org/submit-an-idea-or-tip/ +[3]: https://fedoramagazine.org/wp-content/uploads/2018/11/akash-angle-desktop-300x259.png +[4]: https://fedoramagazine.org/getting-started-flatpak/ +[5]: https://fedoramagazine.org/screenshot-everything-shutter-fedora/ +[6]: https://fedoramagazine.org/wp-content/uploads/2018/11/Fedora-16-300x188.png +[7]: https://fedoramagazine.org/wp-content/uploads/2018/11/wallpaper2you_72588-300x169.jpg diff --git a/translated/tech/20181117 How to enter single user mode in SUSE 12 Linux.md b/published/201811/20181117 How to enter single user mode in SUSE 12 Linux.md similarity index 66% rename from translated/tech/20181117 How to enter single user mode in SUSE 12 Linux.md rename to published/201811/20181117 How to enter single user mode in SUSE 12 Linux.md index 1a098bb0ab..333beaad19 100644 --- a/translated/tech/20181117 How to enter single user mode in SUSE 12 Linux.md +++ b/published/201811/20181117 How to enter single user mode in SUSE 12 Linux.md @@ -1,20 +1,21 @@ 如何在 SUSE 12 Linux 中进入单用户模式？ ====== -一篇了解如何在 SUSE 12 Linux 服务器中进入单用户模式的简短文章。 + +> 一篇了解如何在 SUSE 12 Linux 服务器中进入单用户模式的简短文章。 ![How to enter single user mode in SUSE 12 Linux][1] -在这篇简短的文章中，我们将向你介绍在 SUSE 12 Linux 中进入单用户模式的步骤。在排除系统主要问题时，单用户模式始终是首选。单用户模式禁用网并且没有其他用户登录，你可以排除许多多用户系统的情况，可以帮助你快速排除故障。单用户模式最常见的一种用处是[重置忘记的 root 密码][2]。 +在这篇简短的文章中，我们将向你介绍在 SUSE 12 Linux 中进入单用户模式的步骤。在排除系统主要问题时，单用户模式始终是首选。单用户模式禁用网络并且没有其他用户登录，你可以排除许多多用户系统的情况，可以帮助你快速排除故障。单用户模式最常见的一种用处是[重置忘记的 root 密码][2]。 -### 1\. 暂停启动过程 +### 1、暂停启动过程 -首先，你需要拥有机器的控制台才能进入单用户模式。如果它是 VM 就要 VM 控制台，如果它是物理机那么你需要连接它的 iLO/串口控制台。重启系统并按任意键停止 grub 启动菜单中的内核自动启动。 +首先，你需要拥有机器的控制台才能进入单用户模式。如果它是虚拟机那就是虚拟机控制台，如果它是物理机那么你需要连接它的 iLO/串口控制台。重启系统并在 GRUB 启动菜单中按任意键停止内核的自动启动。 ![Kernel selection menu at boot in SUSE 12][3] -### 2\. 编辑内核的启动选项 +### 2、编辑内核的启动选项 -进入上面的页面后，在所选内核（通常是你首选的最新内核）上按 “e” 更新其启动选项。你会看到下面的页面。 +进入上面的页面后，在所选内核（通常是你首选的最新内核）上按 `e` 更新其启动选项。你会看到下面的页面。 ![grub2 edits in SUSE 12][4] @@ -22,9 +23,9 @@ ![Edit to boot in single user shell][5] -### 3\. 引导编辑后的内核 +### 3、引导编辑后的内核 -现在按 `Ctrl-x` 或 `F10` 来启动这个编辑过的内核。内核将以单用户模式启动，你将看到井号提示符，即有服务器的 root 访问权限。此时，根文件系统以只读模式挂载。因此，你对系统所做的任何更改都不会被保存。 +现在按 `Ctrl-x` 或 `F10` 来启动这个编辑过的内核。内核将以单用户模式启动，你将看到 `#` 号提示符，即有服务器的 root 访问权限。此时，根文件系统以只读模式挂载。因此，你对系统所做的任何更改都不会被保存。 运行以下命令以将根文件系统重新挂载为可重写入的。 @@ -41,7 +42,7 @@ via: https://kerneltalks.com/howto/how-to-enter-single-user-mode-in-suse-12-linu 作者：[kerneltalks][a] 选题：[lujun9972][b] 译者：[geekpi](https://github.com/geekpi) -校对：[校对者ID](https://github.com/校对者ID) +校对：[wxy](https://github.com/wxy) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 diff --git a/published/201811/20181119 How To Customize Bash Prompt In Linux.md b/published/201811/20181119 How To Customize Bash Prompt In Linux.md new file mode 100644 index 0000000000..190fdb914b --- /dev/null +++ b/published/201811/20181119 How To Customize Bash Prompt In Linux.md @@ -0,0 +1,313 @@ +在 Linux 上自定义 bash 命令提示符 +====== + +![](https://www.ostechnix.com/wp-content/uploads/2017/10/BASH-720x340.jpg) + +众所周知，**bash**（the **B**ourne-**A**gain **Sh**ell）是目前绝大多数 Linux 发行版使用的默认 shell。本文将会介绍如何通过添加颜色和样式来自定义 bash 命令提示符的显示。尽管很多插件或工具都可以很轻易地满足这一需求，但我们也可以不使用插件和工具，自己手动自定义一些基本的显示方式，例如添加或者修改某些元素、更改前景色、更改背景色等等。 + +### 在 Linux 中自定义 bash 命令提示符 + +在 bash 中，我们可以通过更改 `$PS1` 环境变量的值来自定义 bash 命令提示符。 + +一般情况下，bash 命令提示符会是以下这样的形式： + +![](https://www.ostechnix.com/wp-content/uploads/2017/10/Linux-Terminal.png) + +在上图这种默认显示形式当中，“sk” 是我的用户名，而 “ubuntuserver” 是我的主机名。 + +只要插入一些以反斜杠开头的特殊转义字符串，就可以按照你的喜好修改命令提示符了。下面我来举几个例子。 + +在开始之前，我强烈建议你预先备份 `~/.bashrc` 文件。 + +``` +$ cp ~/.bashrc ~/.bashrc.bak +``` + +#### 更改 bash 命令提示符中的 username@hostname 部分 + +如上所示，bash 命令提示符一般都带有 “username@hostname” 部分，这个部分是可以修改的。 + +只需要编辑 `~/.bashrc` 文件： + +``` +$ vi ~/.bashrc +``` + +在文件的最后添加一行： + +``` +PS1="ostechnix> " +``` + +将上面的 “ostechnix” 替换为任意一个你想使用的单词，然后按 `ESC` 并输入 `:wq` 保存、退出文件。 + +执行以下命令使刚才的修改生效： + +``` +$ source ~/.bashrc +``` + +你就可以看见 bash 命令提示符中出现刚才添加的 “ostechnix” 了。 + +![][3] + +再来看看另一个例子，比如将 “username@hostname” 替换为 “Hello@welcome>”。 + +同样是像刚才那样修改 `~/.bashrc` 文件。 + +``` +export PS1="Hello@welcome> " +``` + +然后执行 `source ~/.bashrc` 让修改结果立即生效。 + +以下是我在 Ubuntu 18.04 LTS 上修改后的效果。 + +![](https://www.ostechnix.com/wp-content/uploads/2017/10/bash-prompt-1.png) + +#### 仅显示用户名 + +如果需要仅显示用户名，只需要在 `~/.bashrc` 文件中加入以下这一行。 + +``` +export PS1="\u " +``` + +这里的 `\u` 就是一个转义字符串。 + +下面提供了一些可以添加到 `$PS1` 环境变量中的用以改变 bash 命令提示符样式的转义字符串。每次修改之后，都需要执行 `source ~/.bashrc` 命令才能立即生效。 + +#### 显示用户名和主机名 + +``` +export PS1="\u\h " +``` + +命令提示符会这样显示： + +``` +skubuntuserver +``` + +#### 显示用户名和完全限定域名 + +``` +export PS1="\u\H " +``` + +#### 在用户名和主机名之间显示其它字符 + +如果你还需要在用户名和主机名之间显示其它字符（例如 `@`），可以使用以下格式： + +``` +export PS1="\u@\h " +``` + +命令提示符会这样显示： + +``` +sk@ubuntuserver +``` + +#### 显示用户名、主机名，并在末尾添加 $ 符号 + +``` +export PS1="\u@\h\\$ " +``` + +#### 综合以上两种显示方式 + +``` +export PS1="\u@\h> " +``` + +命令提示符最终会这样显示： + +``` +sk@ubuntuserver> +``` + +相似地，还可以添加其它特殊字符，例如冒号、分号、星号、下划线、空格等等。 + +#### 显示用户名、主机名、shell 名称 + +``` +export PS1="\u@\h>\s " +``` + +#### 显示用户名、主机名、shell 名称以及 shell 版本 + +``` +export PS1="\u@\h>\s\v " +``` + +bash 命令提示符显示样式： + +![][4] + +#### 显示用户名、主机名、当前目录 + +``` +export PS1="\u@\h\w " +``` + +如果当前目录是 `$HOME` ，会以一个波浪线（`~`）显示。 + +#### 在 bash 命令提示符中显示日期 + +除了用户名和主机名，如果还想在 bash 命令提示符中显示日期，可以在 `~/.bashrc` 文件中添加以下内容： + +``` +export PS1="\u@\h>\d " +``` + +![][5] + +#### 在 bash 命令提示符中显示日期及 12 小时制时间 + +``` +export PS1="\u@\h>\d\@ " +``` + +#### 显示日期及 hh:mm:ss 格式时间 + +``` +export PS1="\u@\h>\d\T " +``` + +#### 显示日期及 24 小时制时间 + +``` +export PS1="\u@\h>\d\A " +``` + +#### 显示日期及 24 小时制 hh:mm:ss 格式时间 + +``` +export PS1="\u@\h>\d\t " +``` + +以上是一些常见的可以改变 bash 命令提示符的转义字符串。除此以外的其它转义字符串，可以在 bash 的 man 手册 PROMPTING 章节中查阅。 + +你也可以随时执行以下命令查看当前的命令提示符样式。 + +``` +$ echo $PS1 +``` + +#### 在 bash 命令提示符中去掉 username@hostname 部分 + +如果我不想做任何调整，直接把 username@hostname 部分整个去掉可以吗？答案是肯定的。 + +如果你是一个技术方面的博主，你有可能会需要在网站或者博客中上传自己的 Linux 终端截图。或许你的用户名和主机名太拉风、太另类，不想让别人看到，在这种情况下，你就需要隐藏命令提示符中的 “username@hostname” 部分。 + +如果你不想暴露自己的用户名和主机名，只需要按照以下步骤操作。 + +编辑 `~/.bashrc` 文件： + +``` +$ vi ~/.bashrc +``` + +在文件末尾添加这一行： + +``` +PS1="\W> " +``` + +输入 `:wq` 保存并关闭文件。 + +执行以下命令让修改立即生效。 + +``` +$ source ~/.bashrc +``` + +现在看一下你的终端，“username@hostname” 部分已经消失了，只保留了一个 `~>` 标记。 + +![][6] + +如果你想要尽可能简单的操作，又不想弄乱你的 `~/.bashrc` 文件，最好的办法就是在系统中创建另一个用户（例如 “user@example”、“admin@demo”）。用带有这样的命令提示符的用户去截图或者录屏，就不需要顾虑自己的用户名或主机名被别人看见了。 + +**警告：**在某些情况下，这种做法并不推荐。例如像 zsh 这种 shell 会继承当前 shell 的设置，这个时候可能会出现一些意想不到的问题。这个技巧只用于隐藏命令提示符中的 “username@hostname” 部分，仅此而已，如果把这个技巧挪作他用，也可能会出现异常。 + +### 为 bash 命令提示符着色 + +目前我们也只是变更了 bash 命令提示符中的内容，下面介绍一下如何对命令提示符进行着色。 + +通过向 `~/.bashrc` 文件写入一些配置，可以修改 bash 命令提示符的前景色（也就是文本的颜色）和背景色。 + +例如，下面这一行配置可以令某些文本的颜色变成红色： + +``` +export PS1="\u@\[\e[31m\]\h\[\e[m\] " +``` + +添加配置后，执行 `source ~/.bashrc` 立即生效。 + +你的 bash 命令提示符就会变成这样： + +![][7] + +类似地，可以用这样的配置来改变背景色： + +``` +export PS1="\u@\[\e[31;46m\]\h\[\e[m\] " +``` + +![][8] + +### 添加 emoji + +大家都喜欢 emoji。还可以按照以下配置把 emoji 插入到命令提示符中。 + +``` +PS1="\W 🔥 >" +``` + +需要注意的是，emoji 的显示取决于使用的字体，因此某些终端可能会无法正常显示 emoji，取而代之的是一些乱码或者单色表情符号。 + +### 自定义 bash 命令提示符有点难，有更简单的方法吗？ + +如果你是一个新手，编辑 `$PS1` 环境变量的过程可能会有些困难，因为命令提示符中的大量转义字符串可能会让你有点晕头转向。但不要担心，有一个在线的 bash `$PS1` 生成器可以帮助你轻松生成各种 `$PS1` 环境变量值。 + +就是这个[网站][9]： + +[![EzPrompt](https://www.ostechnix.com/wp-content/uploads/2017/10/EzPrompt.png)][9] + +只需要直接选择你想要的 bash 命令提示符样式，添加颜色、设计排序，然后就完成了。你可以预览输出，并将配置代码复制粘贴到 `~/.bashrc` 文件中。就这么简单。顺便一提，本文中大部分的示例都是通过这个网站制作的。 + +### 我把我的 ~/.bashrc 文件弄乱了，该如何恢复？ + +正如我在上面提到的，强烈建议在更改 `~/.bashrc` 文件前做好备份（在更改其它重要的配置文件之前也一定要记得备份）。这样一旦出现任何问题，你都可以很方便地恢复到更改之前的配置状态。当然，如果你忘记了备份，还可以按照下面这篇文章中介绍的方法恢复为默认配置。 + +- [如何将 `~/.bashrc` 文件恢复到默认配置][10] + +这篇文章是基于 ubuntu 的，但也适用于其它的 Linux 发行版。不过事先声明，这篇文章的方法会将 `~/.bashrc` 文件恢复到系统最初时的状态，你对这个文件做过的任何修改都将丢失。 + +感谢阅读！ + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/hide-modify-usernamelocalhost-part-terminal/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[HankChow](https://github.com/HankChow) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: https://www.ostechnix.com/cdn-cgi/l/email-protection +[2]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[3]: http://www.ostechnix.com/wp-content/uploads/2017/10/Linux-Terminal-2.png +[4]: http://www.ostechnix.com/wp-content/uploads/2017/10/bash-prompt-2.png +[5]: http://www.ostechnix.com/wp-content/uploads/2017/10/bash-prompt-3.png +[6]: http://www.ostechnix.com/wp-content/uploads/2017/10/Linux-Terminal-1.png +[7]: http://www.ostechnix.com/hide-modify-usernamelocalhost-part-terminal/bash-prompt-4/ +[8]: http://www.ostechnix.com/hide-modify-usernamelocalhost-part-terminal/bash-prompt-5/ +[9]: http://ezprompt.net/ +[10]: https://www.ostechnix.com/restore-bashrc-file-default-settings-ubuntu/ + diff --git a/published/201811/20181120 How To Change GDM Login Screen Background In Ubuntu.md b/published/201811/20181120 How To Change GDM Login Screen Background In Ubuntu.md new file mode 100644 index 0000000000..9fbf743381 --- /dev/null +++ b/published/201811/20181120 How To Change GDM Login Screen Background In Ubuntu.md @@ -0,0 +1,86 @@ +如何更换 Ubuntu 系统的 GDM 登录界面背景 +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/GDM-login-screen-3.png) + +Ubuntu 18.04 LTS 桌面系统在登录、锁屏和解锁状态下，我们会看到一个纯紫色的背景。它是 GDM（GNOME 显示管理器GNOME Display Manager）从 ubuntu 17.04 版本开始使用的默认背景。有一些人可能会不喜欢这个纯色的背景，想换一个酷一点、更吸睛的！如果是这样，你找对地方了。这篇短文将会告诉你如何更换 Ubuntu 18.04 LTS 的 GDM 登录界面的背景。 + +### 更换 Ubuntu 的登录界面背景 + +这是 Ubuntu 18.04 LTS 桌面系统默认的登录界面。 + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/GDM-login-screen-1.png) + +不管你喜欢与否，你总是会不经意在登录、解屏/锁屏的时面对它。别担心！你可以随便更换一个你喜欢的图片。 + +在 Ubuntu 上更换桌面壁纸和用户的资料图像不难。我们可以点击鼠标就搞定了。但更换解屏/锁屏的背景则需要修改文件 `ubuntu.css`，它位于 `/usr/share/gnome-shell/theme`。 + +修改这个文件之前，最好备份一下它。这样我们可以避免出现问题时可以恢复它。 + +``` +$ sudo cp /usr/share/gnome-shell/theme/ubuntu.css /usr/share/gnome-shell/theme/ubuntu.css.bak +``` + +修改文件 `ubuntu.css`： + +``` +$ sudo nano /usr/share/gnome-shell/theme/ubuntu.css +``` + +在文件中找到关键字 `lockDialogGroup`，如下行： + +``` +#lockDialogGroup { + background: #2c001e url(resource:///org/gnome/shell/theme/noise-texture.png); + background-repeat: repeat; +} +``` + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/ubuntu_css.png) + +可以看到，GDM 默认登录的背景图片是 `noise-texture.png`。 + +现在修改为你自己的图片路径。也可以选择 .jpg 或 .png 格式的文件，两种格式的图片文件都是支持的。修改完成后的文件内容如下： + +``` +#lockDialogGroup { + background: #2c001e url(file:///home/sk/image.png); + background-repeat: no-repeat; + background-size: cover; + background-position: center; +} +``` + +请注意 `ubuntu.css` 文件里这个关键字的修改，我把修改点加粗了。 + +你可能注意到，我把原来的 `... url(resource:///org/gnome/shell/theme/noise-texture.png);` 修改为 `... url(file:///home/sk/image.png);`。也就是说，你可以把 `... url(resource ...` 修改为 `.. url(file ...`。 + +同时，你可以把参数 `background-repeat:` 的值 `repeat` 修改为 `no-repeat`，并增加另外两行。你可以直接复制上面几行的修改到你的 `ubuntu.css` 文件，对应的修改为你的图片路径。 + +修改完成后，保存和关闭此文件。然后系统重启生效。 + +下面是 GDM 登录界面的最新背景图片： + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/GDM-login-screen-2.png) + +是不是很酷，你都看到了，更换 GDM 登录的默认背景很简单。你只需要修改 `ubuntu.css` 文件中图片的路径然后重启系统。是不是很简单也很有意思. + +你可以修改 `/usr/share/gnome-shell/theme` 目录下的文件 `gdm3.css` ，具体修改内容和修改结果和上面一样。同时记得修改前备份要修改的文件。 + +就这些了。如果有好的东东再分享了，请大家关注！ + +后会有期。 + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/how-to-change-gdm-login-screen-background-in-ubuntu/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[Guevaraya](https://github.com/guevaraya) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 diff --git a/published/201811/20181126 How to use multiple programming languages without losing your mind.md b/published/201811/20181126 How to use multiple programming languages without losing your mind.md new file mode 100644 index 0000000000..bbb310fa4e --- /dev/null +++ b/published/201811/20181126 How to use multiple programming languages without losing your mind.md @@ -0,0 +1,71 @@ +[#]: collector: (lujun9972) +[#]: translator: (heguangzhi) +[#]: reviewer: (wxy) +[#]: publisher: (wxy) +[#]: subject: (How to use multiple programming languages without losing your mind) +[#]: via: (https://opensource.com/article/18/11/multiple-programming-languages) +[#]: author: (Bart Copeland https://opensource.com/users/bartcopeland) +[#]: url: (https://linux.cn/article-10291-1.html) + +如何使用多种编程语言而又不失理智 +====== + +> 多语言编程环境是一把双刃剑，既带来好处，也带来可能威胁组织的复杂性。 + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/books_programming_languages.jpg?itok=KJcdnXM2) + +如今，随着各种不同的编程语言的出现，许多组织已经变成了数字多语种组织digital polyglots。开源打开了一个语言和技术堆栈的世界，开发人员可以使用这些语言和技术堆栈来完成他们的任务，包括开发、支持过时的和现代的软件应用。 + +与那些只说母语的人相比，通晓多种语言的人可以与数百万人交谈。在软件环境中，开发人员不会引入新的语言来达到特定的目的，也不会更好地交流。一些语言对于一项任务来说很棒，但是对于另一项任务来说却不行，因此使用多种编程语言可以让开发人员使用合适的工具来完成这项任务。这样，所有的开发都是多语种的；这只是野兽的本性。 + +多语种环境的创建通常是渐进的和情景化的。例如，当一家企业收购一家公司时，它就承担了该公司的技术堆栈 —— 包括其编程语言。或者，随着技术领导的改变，新的领导者可能会将不同的技术纳入其中。技术也有过时的时候，随着时间的推移，增加了组织必须维护的编程语言和技术的数量。 + +多语言环境对企业来说是一把双刃剑，既带来好处，也带来复杂性和挑战。最终，如果这种情况得不到控制，多语言将会扼杀你的企业。 + +### 棘手的技术绕口令 + +如果有多种不同的技术 —— 编程语言、过时的工具和新兴的技术堆栈 —— 就有复杂性。工程师团队花更多的时间努力改进编程语言，包括许可证、安全性和依赖性。与此同时，管理层缺乏对代码合规性的监督，无法衡量风险。 + +发生的情况是，企业具有不同程度的编程语言质量和工具支持的高度可变性。当你需要和十几个人一起工作时，很难成为一种语言的专家。一个能流利地说法语和意大利语的人和一个能用八种语言串成几个句子的人在技能水平上有很大差异。开发人员和编程语言也是如此。 + +随着更多编程语言的加入，困难只会增加，导致数字巴别塔的出现。 + +答案是不要拿走开发人员工作所需的工具。添加新的编程语言可以建立他们的技能基础，并为他们提供合适的设备来完成他们的工作。所以，你想对你的开发者说“是”，但是随着越来越多的编程语言被添加到企业中，它们会拖累你的软件开发生命周期（SDLC）。在规模上，所有这些语言和工具都可能扼杀企业。 + +企业应注意三个主要问题: + +1. **可见性：** 团队聚在一起执行项目，然后解散。应用程序已经发布，但从未更新 —— 为什么要修复那些没有被破坏的东西？因此，当发现一个关键漏洞时，企业可能无法了解哪些应用程序受到影响，这些应用程序包含哪些库，甚至无法了解它们是用什么语言构建的。这可能导致成本高昂的“勘探项目”，以确保漏洞得到适当解决。 + +2. **更新或编码：** 一些企业将更新和修复功能集中在一个团队中。其他人要求每个“比萨团队”管理自己的开发工具。无论是哪种情况，工程团队和管理层都要付出机会成本：这些团队没有编码新特性，而是不断更新和修复开源工具中的库，因为它们移动得如此之快。 + +3. **重新发明轮子：** 由于代码依赖性和库版本不断更新，当发现漏洞时，与应用程序原始版本相关联的工件可能不再可用。因此，许多开发周期都被浪费在试图重新创建一个可以修复漏洞的环境上。 + +将你组织中的每种编程语言乘以这三个问题，开始时被认为是分子一样小的东西突然看起来像珠穆朗玛峰。就像登山者一样，没有合适的设备和工具，你将无法生存。 + +### 找到你的罗塞塔石碑 + +一个全面的解决方案可以满足 SDLC 中企业及其个人利益相关者的需求。企业可以使用以下最佳实践创建解决方案: + + 1. 监控生产中运行的代码，并根据应用程序中使用的标记组件（例如，常见漏洞和暴露组件）的风险做出响应。 + 2. 定期接收更新以保持代码的最新和无错误。 + 3. 使用商业开源支持来获得编程语言版本和平台的帮助，这些版本和平台已经接近尾声，并且不受社区支持。 + 4. 标准化整个企业中的特定编程语言构建，以实现跨团队的一致环境，并最大限度地减少依赖性。 + 5. 根据相关性设置何时触发更新、警报或其他类型事件的阈值。 + 6. 为您的包管理创建一个单一的可信来源；这可能需要知识渊博的技术提供商的帮助。 + 7. 根据您的特定标准，只使用您需要的软件包获得较小的构建版本。 + +使用这些最佳实践，开发人员可以最大限度地利用他们的时间为企业创造更多价值，而不是执行基本的工具或构建工程任务。这将在软件开发生命周期（SDLC）的所有环境中创建代码一致性。由于维护编程语言和软件包分发所需的资源更少，这也将提高效率和节约成本。这种新的操作方式将使技术人员和管理人员的生活更加轻松。 + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/11/multiple-programming-languages + +作者：[Bart Copeland][a] +选题：[lujun9972][b] +译者：[heguangzhi](https://github.com/heguangzhi) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/bartcopeland +[b]: https://github.com/lujun9972 diff --git a/published/201812/20111221 30 Best Sources For Linux - -BSD - Unix Documentation On the Web.md b/published/201812/20111221 30 Best Sources For Linux - -BSD - Unix Documentation On the Web.md new file mode 100644 index 0000000000..0f51e0e7a9 --- /dev/null +++ b/published/201812/20111221 30 Best Sources For Linux - -BSD - Unix Documentation On the Web.md @@ -0,0 +1,401 @@ +学习 Linux/*BSD/Unix 的 30 个最佳在线文档 +====== + +手册页（man）是由系统管理员和 IT 技术开发人员写的，更多的是为了作为参考而不是教你如何使用。手册页对于已经熟悉使用 Linux、Unix 和 BSD 操作系统的人来说是非常有用的。如果你仅仅需要知道某个命令或者某个配置文件的格式那么你可以使用手册页，但是手册页对于 Linux 新手来说并没有太大的帮助。想要通过使用手册页来学习一些新东西不是一个好的选择。这里有将提供 30 个学习 Linux 和 Unix 操作系统的最佳在线网页文档。 + +![Dennis Ritchie and Ken Thompson working with UNIX PDP11][1] + +值得一提的是，相对于 Linux，BSD 的手册页更好。 + +### #1：Red Hat Enterprise Linux（RHEL） + +![Red hat Enterprise Linux 文档][2] + +RHEL 是由红帽公司开发的面向商业市场的 Linux 发行版。红帽的文档是最好的文档之一，涵盖从 RHEL 的基础到一些高级主题比如安全、SELinux、虚拟化、目录服务器、服务器集群、JBOSS 应用程序服务器、高可用性集群（HPC）等。红帽的文档已经被翻译成 22 种语言，发布成多页面 HTML、单页面 HTML、PDF、EPUB 等文件格式。好消息同样的文档你可以用于 Centos 和 Scientific Linux（社区企业发行版）。这些文档随操作系统一起下载提供，也就是说当你没有网络的时候，你也可以使用它们。RHEL 的文档**涵盖从安装到配置器群的所有内容**。唯一的缺点是你需要成为付费用户。当然这对于企业公司来说是一件完美的事。 + +1. RHEL 文档：[HTML/PDF格式][3]（LCTT 译注：**此链接**需要付费用户才可以访问） +2. 是否支持论坛：只能通过红帽公司的用户网站提交支持案例。 + +#### 关于 CentOS Wiki 和论坛的说明 + +![Centos Linux Wiki][4] + +CentOS（社区企业操作系统Community ENTerprise Operating System）是由 RHEL 提供的自由源码包免费重建的。它为个人电脑或其它用途提供了可靠的、免费的企业级 Linux。你可以不用付出任何支持和认证费用就可以获得 RHEL 的稳定性。CentOS的 wiki 分为 Howto、技巧等等部分，链接如下： + +1. 文档：[wiki 格式][87] +2. 是否支持论坛：[是][88] + +### #2：Arch 的 Wiki 和论坛 + +![Arch Linux wiki 和教程][5] + +Arch linux 是一个独立开发的 Linux 操作系统，它有基于 wiki 网站形式的非常不错的文档。它是由 Arch 社区的一些用户共同协作开发出来的，并且允许任何用户添加或修改内容。这些文档教程被分为几类比如说优化、软件包管理、系统管理、X window 系统还有获取安装 Arch Linux 等。它的[官方论坛][7]在解决许多问题的时候也非常有用。它有总共 4 万多个注册用户、超过 1 百万个帖子。 该 wiki 包含一些 **其它 Linux 发行版也适用的通用信息**。 + +1. Arch 社区文档：[Wiki 格式][8] +2. 是否支持论坛：[是][7] + +### #3：Gentoo Linux Wiki 和论坛 + +![Gentoo Linux 手册和 Wiki][9] + +Gentoo Linux 基于 Portage 包管理系统。Gentoo Linux 用户根据它们选择的配置在本地编译源代码。多数 Gentoo Linux 用户都会定制自己独有的程序集。 Gentoo Linux 的文档会给你一些有关 Gentoo Linux 操作系统的说明和一些有关安装、软件包、网络和其它等主要出现的问题的解决方法。Gentoo 有对你来说 **非常有用的论坛**，论坛中有超过 13 万 4 千的用户，总共发了有 5442416 个文章。 + +1. Gentoo 社区文档：[手册][10] 和 [Wiki 格式][11] +2. 是否支持论坛：[是][12] + +### #4：Ubuntu Wiki 和文档 + +![Ubuntu Linux Wiki 和论坛][14] + +Ubuntu 是领先的台式机和笔记本电脑发行版之一。其官方文档由 Ubuntu 文档工程开发维护。你可以在从官方文档中查看大量的信息，比如如何开始使用 Ubuntu 的教程。最好的是，此处包含的这些信息也可用于基于 Debian 的其它系统。你可能会找到由 Ubuntu 的用户们创建的社区文档，这是一份有关 Ubuntu 的使用教程和技巧等。Ubuntu Linux 有着网络上最大的 Linux 社区的操作系统，它对新用户和有经验的用户均有助益。 + +1. Ubuntu 社区文档：[wiki 格式][15] +2. Ubuntu 官方文档：[wiki 格式][16] +3. 是否支持论坛：[是][17] + +### #5：IBM Developer Works + +![IBM: Linux 程序员和系统管理员用到的技术][18] + +IBM Developer Works 为 Linux 程序员和系统管理员提供技术资源，其中包含数以百计的文章、教程和技巧来协助 Linux 程序员的编程工作和应用开发还有系统管理员的日常工作。 + +1. IBM 开发者项目文档：[HTML 格式][19] +2. 是否支持论坛：[是][20] + +### #6：FreeBSD 文档和手册 + +![Freebsd Documentation][21] + +FreeBSD 的手册是由 FreeBSD 文档项目FreeBSD Documentation Project所创建的，它介绍了 FreeBSD 操作系统的安装、管理和一些日常使用技巧等内容。FreeBSD 的手册页通常比 GNU Linux 的手册页要好一点。FreeBSD **附带有全部最新手册页的文档**。 FreeBSD 手册涵盖任何你想要的内容。手册包含一些通用的 Unix 资料，这些资料同样适用于其它的 Linux 发行版。FreeBSD 官方论坛会在你遇到棘手问题时给予帮助。 + +1. FreeBSD 文档：[HTML/PDF 格式][90] +2. 是否支持论坛：[是][91] + +### #7：Bash Hackers Wiki + +![Bash Hackers wiki][22] + +这是一个对于 bash 使用者来说非常好的资源。Bash 使用者的 wiki 是为了归纳所有类型的 GNU Bash 文档。这个项目的动力是为了提供可阅读的文档和资料来避免用户被迫一点一点阅读 Bash 的手册，有时候这是非常麻烦的。Bash Hackers Wiki 分为各个类，比如说脚本和通用资料、如何使用、代码风格、bash 命令格式和其它。 + +1. Bash 用户教程：[wiki 格式][23] + +### #8：Bash 常见问题 + +![Bash 常见问题：一些有关 GNU/BASH 常见问题的解决方法][24] + +这是一个为 bash 新手设计的一个 wiki。它收集了 IRC 网络的 #bash 频道里常见问题的解决方法，这些解决方法是由该频道的普通成员提供。当你遇到问题的时候不要忘了在 [BashPitfalls][25] 部分检索查找答案。这些常见问题的解决方法可能会倾向于 Bash，或者偏向于最基本的 Bourne Shell，这决定于是谁给出的答案。大多数情况会尽力提供可移植的（Bourne）和高效的（Bash，在适当情况下）的两类答案。 + +1. Bash 常见问题：[wiki 格式][26] + +### #9: Howtoforge - Linux 教程 + +![Howtoforge][27] + +博客作者 Falko 在 Howtoforge 上有一些非常不错的东西。这个网站提供了 Linux 关于各种各样主题的教程，比如说其著名的“最佳服务器系列”，网站将主题分为几类，比如说 web 服务器、linux 发行版、DNS 服务器、虚拟化、高可用性、电子邮件和反垃圾邮件、FTP 服务器、编程主题还有一些其它的内容。这个网站也支持德语。 + +1. Howtoforge： [html 格式][28] +2. 是否支持论坛：是 + +### #10：OpenBSD 常见问题和文档 + +![OpenBSD 文档][29] + +OpenBSD 是另一个基于 BSD 的类 Unix 计算机操作系统。OpenBSD 是由 NetBSD 项目分支而来。OpenBSD 因高质量的代码和文档、对软件许可协议的坚定立场和强烈关注安全问题而闻名。OpenBSD 的文档分为多个主题类别，比如说安装、包管理、防火墙设置、用户管理、网络、磁盘和磁盘阵列管理等。 + +1. OpenBSD：[html 格式][30] +2. 是否支持论坛：否，但是可以通过 [邮件列表][31] 来咨询 + +### #11: Calomel - 开源研究和参考文档 + +![开源研究和参考文档][32] + +这个极好的网站是专门作为开源软件和那些特别专注于 OpenBSD 的软件的文档来使用的。这是最简洁的引导网站之一，专注于高质量的内容。网站内容分为多个类，比如说 DNS、OpenBSD、安全、web 服务器、Samba 文件服务器、各种工具等。 + +1. Calomel 官网：[html 格式][33] +2. 是否支持论坛：否 + +### #12：Slackware 书籍项目 + +![Slackware Linux 手册和文档][34] + +Slackware Linux 是我的第一个 Linux 发行版。Slackware 是基于 Linux 内核的最早的发行版之一，也是当前正在维护的最古老的 Linux 发行版。 这个发行版面向专注于稳定性的高级用户。 Slackware 也是很少有的的“类 Unix” 的 Linux 发行版之一。官方的 Slackware 手册是为了让用户快速开始了解 Slackware 操作系统的使用方法而设计的。 这不是说它将包含发行版的每一个方面，而是为了说明它的实用性和给使用者一些有关系统的基础工作使用方法。手册分为多个主题，比如说安装、网络和系统配置、系统管理、包管理等。 + +1. Slackware Linux 手册：[html 格式][35]、pdf 和其它格式 +2. 是否支持论坛：是 + +### #13：Linux 文档项目（TLDP） + +![Linux 学习网站和文档][36] + +Linux 文档项目Linux Documentation Project旨在给 Linux 操作系统提供自由、高质量文档。网站是由志愿者创建和维护的。网站分为具体主题的帮助、由浅入深的指南等。在此我想推荐一个非常好的[文档][37]，这个文档既是一个教程也是一个 shell 脚本编程的参考文档，对于新用户来说这个 HOWTO 的[列表][38]也是一个不错的开始。 + +1. Linux [文档工程][39] 支持多种查阅格式 +2. 是否支持论坛：否 + +### #14：Linux Home Networking + +![Linux Home Networking][40] + +Linux Home Networking 是学习 linux 的另一个比较好的资源，这个网站包含了 Linux 软件认证考试的内容比如 RHCE，还有一些计算机培训课程。网站包含了许多主题，比如说网络、Samba 文件服务器、无线网络、web 服务器等。 + +1. Linux [home networking][41] 可通过 html 格式和 PDF（少量费用）格式查阅 +2. 是否支持论坛：是 + +### #15：Linux Action Show + +![Linux 播客][42] + +Linux Action Show（LAS) 是一个关于 Linux 的播客。这个网站是由 Bryan Lunduke、Allan Jude 和 Chris Fisher 共同管理的。它包含了 FOSS 的最新消息。网站内容主要是评论一些应用程序和 Linux 发行版。有时候也会发布一些和开源项目著名人物的采访视频。 + +1. Linux [action show][43] 支持音频和视频格式 +2. 是否支持论坛：是 + +### #16：Commandlinefu + +![Commandlinefu 的最优 Unix / Linux 命令][45] + +Commandlinefu 列出了各种有用或有趣的 shell 命令。这里所有命令都可以评论、讨论和投票（支持或反对）。对于所有 Unix 命令行用户来说是一个极好的资源。不要忘了查看[评选出来的最佳命令][44]。 + + 1. [Commandlinefu][46] 支持 html 格式 + 2. 是否支持论坛：否 + +### #17：Debian 管理技巧和资源 + +![Debian Linux 管理: 系统管理员技巧和教程][48] + +这个网站包含一些只和 Debian GNU/Linux 相关的主题、技巧和教程，特别是包含了关于系统管理的有趣和有用的信息。你可以在上面贡献文章、建议和问题。提交了之后不要忘记查看[最佳文章列表][47]里有没有你的文章。 + +1. Debian [系统管理][49] 支持 html 格式 +2. 是否支持论坛：否 + +### #18: Catonmat - Sed、Awk、Perl 教程 + +![Sed 流编辑器、 Awk 文本处理工具、 Perl 语言教程][50] + +这个网站是由博客作者 Peteris Krumins 维护的。主要关注命令行和 Unix 编程主题，比如说 sed 流编辑器、perl 语言、AWK 文本处理工具等。不要忘了查看 [sed 介绍][51]、sed 含义解释，还有命令行历史的[权威介绍][53]。 + +1. [catonmat][55] 支持 html 格式 +2. 是否支持论坛：否 + +### #19：Debian GNU/Linux 文档和 Wiki + +![Debian Linux 教程和 Wiki][56] + +Debian 是另外一个 Linux 操作系统，其主要使用的软件以 GNU 许可证发布。Debian 因严格坚持 Unix 和自由软件的理念而闻名，它也是很受欢迎并且有一定影响力的 Linux 发行版本之一。 Ubuntu 等发行版本都是基于 Debian 的。Debian 项目以一种易于访问的形式提供给用户合适的文档。这个网站分为 Wiki、安装指导、常见问题、支持论坛几个模块。 + +1. Debian GNU/Linux [文档][57] 支持 html 和其它格式访问 +2. Debian GNU/Linux [wiki][58] +3. 是否支持论坛：[是][59] + +### #20：Linux Sea + +Linux Sea 这本书提供了比较通俗易懂但充满技术（从最终用户角度来看）的 Linux 操作系统的介绍，使用 Gentoo Linux 作为例子。它既没有谈论 Linux 内核或 Linux 发行版的历史，也没有谈到 Linux 用户不那么感兴趣的细节。 + +1. Linux [sea][60] 支持 html 格式访问 +2. 是否支持论坛: 否 + +### #21：O'reilly Commons + +![免费 Linux / Unix / Php / Javascript / Ubuntu 学习笔记][61] + +O'reilly 出版社发布了不少 wiki 格式的文章。这个网站主要是为了给那些喜欢创作、参考、使用、修改、更新和修订来自 O'Reilly 或者其它来源的素材的社区提供资料。这个网站包含关于 Ubuntu、PHP、Spamassassin、Linux 等的免费书籍。 + +1. Oreilly [commons][62] 支持 Wiki 格式 +2. 是否支持论坛：否 + +### #22：Ubuntu 袖珍指南 + +![Ubuntu 新手书籍][63] + +这本书的作者是 Keir Thomas。这本指南（或者说是书籍）对于所有 ubuntu 用户来说都值得一读。这本书旨在向用户介绍 Ubuntu 操作系统和其所依赖的理念。你可以从官网下载这本书的 PDF 版本，也可以在亚马逊买印刷版。 + +1. Ubuntu [pocket guide][64] 支持 PDF 和印刷版本. +2. 是否支持论坛：否 + +### #23: Linux: Rute User's Tutorial and Exposition + +![GNU/LINUX system administration book][65] + +这本书涵盖了 GNU/LINUX 系统管理，主要是对主流的发布版本比如红帽和 Debian 的说明，可以作为新用户的教程和高级管理员的参考。这本书旨在给出 Unix 系统的每个面的简明彻底的解释和实践性的例子。想要全面了解 Linux 的人都不需要再看了 —— 这里没有涉及的内容。 + +1. Linux: [Rute User's Tutorial and Exposition][66] 支持印刷版和 html 格式 +2. 是否支持论坛：否 + +### #24：高级 Linux 编程 + +![高级 Linux 编程][67] + +这本书是写给那些已经熟悉了 C 语言编程的程序员的。这本书采取一种教程式的方式来讲述大多数在 GNU/Linux 系统应用编程中重要的概念和功能特性。如果你是一个已经对 GNU/Linux 系统编程有一定经验的开发者，或者是对其它类 Unix 系统编程有一定经验的开发者，或者对 GNU/Linux 软件开发有兴趣，或者想要从非 Unix 系统环境转换到 Unix 平台并且已经熟悉了优秀软件的开发原则，那你很适合读这本书。另外，你会发现这本书同样适合于 C 和 C++ 编程。 + +1. [高级 Linux 编程][68] 支持印刷版和 PDF 格式 +2. 是否支持论坛：否 + +### #25: LPI 101 Course Notes + +![Linux 国际专业协会认证书籍][69] + +LPIC 1、2、3 级是用于 Linux 系统管理员认证的。这个网站提供了 LPI 101 和 LPI 102 的测试训练。这些是根据 GNU 自由文档协议GNU Free Documentation Licence（FDL）发布的。这些课程材料基于 Linux 国际专业协会的 LPI 101 和 102 考试的目标。这个课程是为了提供给你一些必备的 Linux 系统的操作和管理的技能。 + +1. LPI [训练手册][70] 支持 PDF 格式 +2. 是否支持论坛：否 + +### #26: FLOSS 手册 + +![FLOSS Manuals is a collection of manuals about free and open source software][72] + +FLOSS 手册是一系列关于自由和开源软件以及用于创建它们的工具和使用这些工具的社区的手册。社区的成员包含作者、编辑、设计师、软件开发者、积极分子等。这些手册中说明了怎样安装使用一些自由和开源软件，如何操作（比如设计和维持在线安全）开源软件，这其中也包含如何使用或支持自由软件和格式的自由文化服务手册。你也会发现关于一些像 VLC、 [Linux 视频编辑][71]、 Linux、 OLPC / SUGAR、 GRAPHICS 等软件的手册。 + +1. 你可以浏览 [FOSS 手册][73] 支持 Wiki 格式 +2. 是否支持论坛：否 + +### #27：Linux 入门包 + +![Linux 入门包][74] + +刚接触 Linux 这个美好世界？想找一个简单的入门方式？你可以下载一个 130 页的指南来入门。这个指南会向你展示如何在你的个人电脑上安装 Linux，如何浏览桌面，掌握最主流行的 Linux 程序和修复可能出现的问题的方法。 + +1. [Linux 入门包][75]支持 PDF 格式 +2. 是否支持论坛：否 + +### #28：Linux.com - Linux 信息来源 + +Linux.com 是 Linux 基金会的一个产品。这个网站上提供一些新闻、指南、教程和一些关于 Linux 的其它信息。利用全球 Linux 用户的力量来通知、写作、连接 Linux 的事务。 + +1. 在线访问 [Linux.com][76] +2. 是否支持论坛：是 + +### #29: LWN + +LWN 是一个注重自由软件及用于 Linux 和其它类 Unix 操作系统的软件的网站。这个网站有周刊、基本上每天发布的单独文章和文章的讨论对话。该网站提供有关 Linux 和 FOSS 相关的开发、法律、商业和安全问题的全面报道。 + +1. 在线访问 [lwn.net][77] +2. 是否支持论坛：否 + +### #30：Mac OS X 相关网站 + +与 Mac OS X 相关网站的快速链接： + +* [Mac OS X 提示][78] —— 这个网站专用于苹果的 Mac OS X Unix 操作系统。网站有很多有关 Bash 和 Mac OS X 的使用建议、技巧和教程 +* [Mac OS 开发库][79] —— 苹果拥有大量和 OS X 开发相关的优秀系列内容。不要忘了看一看 [bash shell 脚本入门][80] +* [Apple 知识库][81] - 这个有点像 RHN 的知识库。这个网站提供了所有苹果产品包括 OS X 相关的指南和故障报修建议。 + +### #30: NetBSD + +（LCTT 译注：没错，又一个 30） + +NetBSD 是另一个基于 BSD Unix 操作系统的自由开源操作系统。NetBSD 项目专注于系统的高质量设计、稳定性和性能。由于 NetBSD 的可移植性和伯克利式的许可证，NetBSD 常用于嵌入式系统。这个网站提供了一些 NetBSD 官方文档和各种第三方文档的链接。 + +1. 在线访问 [netbsd][82] 文档，支持 html、PDF 格式 +2. 是否支持论坛：否 + +### 你要做的事 + +这是我的个人列表，这可能并不完全是权威的，因此如果你有你自己喜欢的独特 Unix/Linux 网站，可以在下方参与评论分享。 + +// 图片来源: [Flickr photo][83] PanelSwitchman。一些连接是用户在我们的 Facebook 粉丝页面上建议添加的。 + +### 关于作者 + +作者是 nixCraft 的创建者和经验丰富的系统管理员以及 Linux 操作系统 / Unix shell 脚本的培训师。它曾与全球客户及各行各业合作，包括 IT、教育，国防和空间研究以及一些非营利部门。可以关注作者的 [Twitter][84]、[Facebook][85]、[Google+][86]。 + +-------------------------------------------------------------------------------- + +via: https://www.cyberciti.biz/tips/linux-unix-bsd-documentations.html + +作者：[Vivek Gite][a] +译者：[ScarboroughCoral](https://github.com/ScarboroughCoral) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.cyberciti.biz +[1]:https://www.cyberciti.biz/media/new/tips/2011/12/unix-pdp11.jpg "Dennis Ritchie and Ken Thompson working with UNIX PDP11" +[2]:https://www.cyberciti.biz/media/new/tips/2011/12/redhat-enterprise-linux-docs.png "Red hat Enterprise Linux Docs" +[3]:https://access.redhat.com/documentation/en-us/ +[4]:https://www.cyberciti.biz/media/new/tips/2011/12/centos-linux-wiki.png "Centos Linux Wiki, Support, Documents" +[5]:https://www.cyberciti.biz/media/new/tips/2011/12/arch-linux-wiki.png "Arch Linux wiki and tutorials " +[6]:https://wiki.archlinux.org/index.php/Category:Networking_%28English%29 +[7]:https://bbs.archlinux.org/ +[8]:https://wiki.archlinux.org/ +[9]:https://www.cyberciti.biz/media/new/tips/2011/12/gentoo-linux-wiki1.png "Gentoo Linux Handbook and Wiki" +[10]:http://www.gentoo.org/doc/en/handbook/ +[11]:https://wiki.gentoo.org +[12]:https://forums.gentoo.org/ +[13]:http://gentoo-wiki.com +[14]:https://www.cyberciti.biz/media/new/tips/2011/12/ubuntu-linux-wiki.png "Ubuntu Linux Wiki and Forums" +[15]:https://help.ubuntu.com/community +[16]:https://help.ubuntu.com/ +[17]:https://ubuntuforums.org/ +[18]:https://www.cyberciti.biz/media/new/tips/2011/12/ibm-devel.png "IBM: Technical for Linux programmers and system administrators" +[19]:https://www.ibm.com/developerworks/learn/linux/index.html +[20]:https://www.ibm.com/developerworks/community/forums/html/public?lang=en +[21]:https://www.cyberciti.biz/media/new/tips/2011/12/freebsd-docs.png "Freebsd Documentation" +[22]:https://www.cyberciti.biz/media/new/tips/2011/12/bash-hackers-wiki.png "Bash hackers wiki for bash users" +[23]:http://wiki.bash-hackers.org/doku.php +[24]:https://www.cyberciti.biz/media/new/tips/2011/12/bash-faq.png "Bash FAQ: Answers to frequently asked questions about GNU/BASH" +[25]:http://mywiki.wooledge.org/BashPitfalls +[26]:https://mywiki.wooledge.org/BashFAQ +[27]:https://www.cyberciti.biz/media/new/tips/2011/12/howtoforge.png "Howtoforge tutorials" +[28]:https://howtoforge.com/ +[29]:https://www.cyberciti.biz/media/new/tips/2011/12/openbsd-faq.png "OpenBSD Documenation" +[30]:https://www.openbsd.org/faq/index.html +[31]:https://www.openbsd.org/mail.html +[32]:https://www.cyberciti.biz/media/new/tips/2011/12/calomel_org.png "Open Source Research and Reference Documentation" +[33]:https://calomel.org +[34]:https://www.cyberciti.biz/media/new/tips/2011/12/slackware-linux-book.png "Slackware Linux Book and Documentation " +[35]:http://www.slackbook.org/ +[36]:https://www.cyberciti.biz/media/new/tips/2011/12/tldp.png "Linux Learning Site and Documentation " +[37]:http://tldp.org/LDP/abs/html/index.html +[38]:http://tldp.org/HOWTO/HOWTO-INDEX/howtos.html +[39]:http://tldp.org/ +[40]:https://www.cyberciti.biz/media/new/tips/2011/12/linuxhomenetworking.png "Linux Home Networking " +[41]:http://www.linuxhomenetworking.com/ +[42]:https://www.cyberciti.biz/media/new/tips/2011/12/linux-action-show.png "Linux Podcast " +[43]:http://www.jupiterbroadcasting.com/show/linuxactionshow/ +[44]:https://www.commandlinefu.com/commands/browse/sort-by-votes +[45]:https://www.cyberciti.biz/media/new/tips/2011/12/commandlinefu.png "The best Unix / Linux Commands " +[46]:https://commandlinefu.com/ +[47]:https://www.debian-administration.org/hof +[48]:https://www.cyberciti.biz/media/new/tips/2011/12/debian-admin.png "Debian Linux Adminstration: Tips and Tutorial For Sys Admin" +[49]:https://www.debian-administration.org/ +[50]:https://www.cyberciti.biz/media/new/tips/2011/12/catonmat.png "Sed, Awk, Perl Tutorials" +[51]:http://www.catonmat.net/blog/worlds-best-introduction-to-sed/ +[52]:https://www.catonmat.net/blog/sed-one-liners-explained-part-one/ +[53]:https://www.catonmat.net/blog/the-definitive-guide-to-bash-command-line-history/ +[54]:https://www.catonmat.net/blog/awk-one-liners-explained-part-one/ +[55]:https://catonmat.net/ +[56]:https://www.cyberciti.biz/media/new/tips/2011/12/debian-wiki.png "Debian Linux Tutorials and Wiki" +[57]:https://www.debian.org/doc/ +[58]:https://wiki.debian.org/ +[59]:https://www.debian.org/support +[60]:http://swift.siphos.be/linux_sea/ +[61]:https://www.cyberciti.biz/media/new/tips/2011/12/orelly.png "Oreilly Free Linux / Unix / Php / Javascript / Ubuntu Books" +[62]:http://commons.oreilly.com/wiki/index.php/O%27Reilly_Commons +[63]:https://www.cyberciti.biz/media/new/tips/2011/12/ubuntu-guide.png "Ubuntu Book For New Users" +[64]:http://ubuntupocketguide.com/ +[65]:https://www.cyberciti.biz/media/new/tips/2011/12/rute.png "GNU/LINUX system administration free book" +[66]:https://web.archive.org/web/20160204213406/http://rute.2038bug.com/rute.html.gz +[67]:https://www.cyberciti.biz/media/new/tips/2011/12/advanced-linux-programming.png "Download Advanced Linux Programming PDF version" +[68]:https://github.com/MentorEmbedded/advancedlinuxprogramming +[69]:https://www.cyberciti.biz/media/new/tips/2011/12/lpic.png "Download Linux Professional Institute Certification PDF Book" +[70]:http://academy.delmar.edu/Courses/ITSC1358/eBooks/LPI-101.LinuxTrainingCourseNotes.pdf +[71]://www.cyberciti.biz/faq/top5-linux-video-editing-system-software/ +[72]:https://www.cyberciti.biz/media/new/tips/2011/12/floss-manuals.png "Download manuals about free and open source software" +[73]:https://flossmanuals.net/ +[74]:https://www.cyberciti.biz/media/new/tips/2011/12/linux-starter.png "New to Linux? Start Linux starter book [ PDF version ]" +[75]:http://www.tuxradar.com/linuxstarterpack +[76]:https://linux.com +[77]:https://lwn.net/ +[78]:http://hints.macworld.com/ +[79]:https://developer.apple.com/library/mac/navigation/ +[80]:https://developer.apple.com/library/mac/#documentation/OpenSource/Conceptual/ShellScripting/Introduction/Introduction.html +[81]:https://support.apple.com/kb/index?page=search&locale=en_US&q= +[82]:https://www.netbsd.org/docs/ +[83]:https://www.flickr.com/photos/9479603@N02/3311745151/in/set-72157614479572582/ +[84]:https://twitter.com/nixcraft +[85]:https://facebook.com/nixcraft +[86]:https://plus.google.com/+CybercitiBiz +[87]:https://wiki.centos.org/ +[88]:https://www.centos.org/forums/ +[90]: https://www.freebsd.org/docs.html +[91]: https://forums.freebsd.org/ diff --git a/published/201812/20171012 7 Best eBook Readers for Linux.md b/published/201812/20171012 7 Best eBook Readers for Linux.md new file mode 100644 index 0000000000..346eed6bb6 --- /dev/null +++ b/published/201812/20171012 7 Best eBook Readers for Linux.md @@ -0,0 +1,188 @@ +7 个最佳 Linux 电子书阅读器 +====== + +**摘要：** 本文中我们涉及一些 Linux 最佳电子书阅读器。这些应用提供更佳的阅读体验甚至可以管理你的电子书。 + +![最佳 Linux 电子书阅读器][1] + +最近，随着人们发现在手持设备、Kindle 或者 PC 上阅读更加舒适，对电子图书的需求有所增加。至于 Linux 用户，也有各种电子书应用满足你阅读和整理电子书的需求。 + +在本文中，我们选出了七个最佳 Linux 电子书阅读器。这些电子书阅读器最适合 pdf、epub 和其他电子书格式。 + +我提供的是 Ubuntu 安装说明，因为我现在使用它。如果你使用的是[非 Ubuntu 发行版][2]，你能在你的发行版软件仓库中找到大多数这些电子书应用。 + +### 1. Calibre + +[Calibre][3] 是 Linux 最受欢迎的电子书应用。老实说，这不仅仅是一个简单的电子书阅读器。它是一个完整的电子书解决方案。你甚至能[通过 Calibre 创建专业的电子书][4]。 + +通过强大的电子书管理和易用的界面，它提供了创建和编辑电子书的功能。Calibre 支持多种格式和与其它电子书阅读器同步。它也可以让你轻松转换一种电子书格式到另一种。 + +Calibre 最大的缺点是，资源消耗太多，因此作为一个独立的电子阅读器来说是一个艰难的选择。 + +![Calibre][5] + +#### 特性 + + * 管理电子书：Calibre 通过管理元数据来排序和分组电子书。你能从各种来源下载一本电子书的元数据或创建和编辑现有的字段。 + * 支持所有主流电子书格式：Calibre 支持所有主流电子书格式并兼容多种电子阅读器。 + * 文件转换：在转换时，你能通过改变电子书风格，创建内容表和调整边距的选项来转换任何一种电子书格式到另一种。你也能转换个人文档为电子书。 + * 从 web 下载杂志期刊：Calibre 能从各种新闻源或者通过 RSS 订阅源传递故事。 + * 分享和备份你的电子图书馆：它提供了一个选项，可以托管你电子书集合到它的服务端，从而你能与好友共享或用任何设备从任何地方访问。备份和导入/导出特性可以确保你的收藏安全和方便携带。 + +#### 安装 + +你能在主流 Linux 发行版的软件库中找到它。对于 Ubuntu，在软件中心搜索它或者使用下面的命令： + +``` +sudo apt-get install calibre +``` + +### 2. FBReader + +![FBReader: Linux 电子书阅读器][6] + +[FBReader][7] 是一个开源的轻量级多平台电子书阅读器，它支持多种格式，比如 ePub、fb2、mobi、rtf、html 等。它包括了一些可以访问的流行网络电子图书馆，那里你能免费或付费下载电子书。 + +#### 特性 + + * 支持多种文件格式和设备比如 Android、iOS、Windows、Mac 和更多。 + * 同步书集、阅读位置和书签。 + * 在线管理你图书馆，可以从你的 Linux 桌面添加任何书到所有设备。 + * 支持 Web 浏览器访问你的书集。 + * 支持将书籍存储在 Google Drive ，可以通过作者，系列或其他属性整理书籍。 + +#### 安装 + +你能从官方库或者在终端中输入以下命令安装 FBReader 电子阅读器。 + +``` +sudo apt-get install fbreader +``` + +或者你能从[这里][8]抓取一个以 .deb 包，并在你的基于 Debian 发行版的系统上安装它。 + +### 3. Okular + +[Okular][9] 是另一个开源的基于 KDE 开发的跨平台文档查看器，它已经作为 KDE 应用发布的一部分了。 + +![Okular][10] + +#### 特性 + + * Okular 支持多种文档格式像 PDF、Postscript、DjVu、CHM、XPS、ePub 和其他。 + * 支持在 PDF 文档中评论、高亮和绘制不同的形状等。 + * 无需修改原始 PDF 文件，分别保存上述这些更改。 + * 电子书中的文本能被提取到一个文本文件，并且有个名为 Jovie 的内置文本阅读服务。 + +备注：查看这个应用的时候，我发现这个应用在 Ubuntu 和它的衍生系统中不支持 ePub 文件格式。其他发行版用户仍然可以发挥它全部的潜力。 + +#### 安装 + +Ubuntu 用户可以在终端中键入下面的命令来安装它： + +``` +sudo apt-get install okular +``` + +### 4. Lucidor + +Lucidor 是一个易用的、支持 epub 文件格式和在 OPDS 格式中编目的电子阅读器。它也具有在本地书架里组织电子书集、从互联网搜索和下载，和将 Web 订阅和网页转换成电子书的功能。 + +Lucidor 是 XULRunner 应用程序，它向您展示了具有类似火狐的选项卡式布局，和存储数据和配置时的行为。它是这个列表中最简单的电子阅读器，包括诸如文本说明和滚动选项之类的配置。 + +![lucidor][11] + +你可以通过选择单词并右击“查找单词”来查找该单词在 Wiktionary.org 的定义。它也包含 web 订阅或 web 页面作为电子书的选项。 + +你能从[这里][12]下载和安装 deb 或者 RPM 包。 + +### 5. Bookworm + +![Bookworm Linux 电子阅读器][13] + +Bookworm 是另一个支持多种文件格式诸如 epub、pdf、mobi、cbr 和 cbz 的自由开源的电子阅读器。我写了一篇关于 Bookworm 应用程序的特性和安装的专题文章，到这里阅读：[Bookworm：一个简单而强大的 Linux 电子阅读器][14] + +#### 安装 + +``` +sudo apt-add-repository ppa:bookworm-team/bookworm +sudo apt-get update +sudo apt-get install bookworm +``` + +### 6. Easy Ebook Viewer + +[Easy Ebook Viewer][15] 是又一个用于读取 ePub 文件的很棒的 GTK Python 应用。具有基本章节导航、从上次阅读位置继续、从其他电子书文件格式导入、章节跳转等功能，Easy Ebook Viewer 是一个简单而简约的 ePub 阅读器. + +![Easy-Ebook-Viewer][16] + +这个应用仍然处于初始阶段，只支持 ePub 文件。 + +#### 安装 + +你可以从 [GitHub][17] 下载源代码，并自己编译它及依赖项来安装 Easy Ebook Viewer。或者，以下终端命令将执行完全相同的工作。 + +``` +sudo apt install git gir1.2-webkit-3.0 libwebkitgtk-3.0-0 gir1.2-gtk-3.0 python3-gi +git clone https://github.com/michaldaniel/Ebook-Viewer.git +cd Ebook-Viewer/ +sudo make install +``` + +成功完成上述步骤后，你可以从 Dash 启动它。 + +### 7. Buka + +Buka 主要是一个具有简单而清爽的用户界面的电子书管理器。它目前支持 PDF 格式，旨在帮助用户更加关注内容。拥有 PDF 阅读器的所有基本特性，Buka 允许你通过箭头键导航，具有缩放选项，并且能并排查看两页。 + +你可以创建单独的 PDF 文件列表并轻松地在它们之间切换。Buka 也提供了一个内置翻译工具，但是你需要有效的互联网连接来使用这个特性。 + +![Buka][19] + +#### 安装 + +你能从[官方下载页面][20]下载一个 AppImage。如果你不知道如何做，请阅读[如何在 Linux 下使用 AppImage][21]。或者，你可以通过命令行安装它： + +``` +sudo snap install buka +``` + +### 结束语 + +就我个人而言，我发现 Calibre 最适合我的需要。当然，Bookworm 看起来很有前途，这几天我经常使用它。不过，电子书应用的选择完全取决于你的喜好。 + +你使用哪个电子书应用呢？在下面的评论中让我们知道。 + + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/best-ebook-readers-linux/ + +作者：[Ambarish Kumar][a] +译者：[zjon](https://github.com/zjon) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://itsfoss.com/author/ambarish/ +[1]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/10/best-ebook-readers-linux.png +[2]:https://itsfoss.com/non-ubuntu-beginner-linux/ +[3]:https://www.calibre-ebook.com +[4]:https://itsfoss.com/create-ebook-calibre-linux/ +[5]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/09/Calibre-800x603.jpeg +[6]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/10/fbreader-800x624.jpeg +[7]:https://fbreader.org +[8]:https://fbreader.org/content/fbreader-beta-linux-desktop +[9]:https://okular.kde.org/ +[10]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/09/Okular-800x435.jpg +[11]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/09/lucidor-2.png +[12]:http://lucidor.org/lucidor/download.php +[13]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/08/bookworm-ebook-reader-linux-800x450.jpeg +[14]:https://itsfoss.com/bookworm-ebook-reader-linux/ +[15]:https://github.com/michaldaniel/Ebook-Viewer +[16]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/09/Easy-Ebook-Viewer.jpg +[17]:https://github.com/michaldaniel/Ebook-Viewer.git +[18]:https://github.com/oguzhaninan/Buka +[19]:https://i0.wp.com/itsfoss.com/wp-content/uploads/2017/09/Buka2-800x555.png +[20]:https://github.com/oguzhaninan/Buka/releases +[21]:https://itsfoss.com/use-appimage-linux/ diff --git a/published/201812/20171108 Continuous infrastructure- The other CI.md b/published/201812/20171108 Continuous infrastructure- The other CI.md new file mode 100644 index 0000000000..67a35c7c3d --- /dev/null +++ b/published/201812/20171108 Continuous infrastructure- The other CI.md @@ -0,0 +1,108 @@ +持续基础设施：另一个 CI +====== + +> 想要提升你的 DevOps 效率吗？将基础设施当成你的 CI 流程中的重要的一环。 + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/BIZ_darwincloud_520x292_0311LL.png?itok=74DLgd8Q) + +持续交付（CD）和持续集成（CI）是 DevOps 的两个众所周知的方面。但在 CI 大肆流行的今天却忽略了另一个关键性的 "I"：基础设施infrastructure。 + +曾经有一段时间 “基础设施”就意味着无头headless的黑盒子、庞大的服务器，和高耸的机架 —— 更不用说漫长的采购流程和对盈余负载的错误估计。后来到了虚拟机时代，把基础设施处理得很好，虚拟化 —— 以前的世界从未有过这样。我们不再需要管理实体的服务器。仅仅是简单的点击，我们就可以创建和销毁、开始和停止、升级和降级我们的服务器。 + +有一个关于银行的流行故事：它们实现了数字化，并且引入了在线表格，用户需要手动填写表格、打印，然后邮寄回银行（LCTT 译注：我真的遇到过有人问我这样的需求怎么办）。这就是我们今天基础设施遇到的情况：使用新技术来做和以前一样的事情。 + +在这篇文章中，我们会看到在基础设施管理方面的进步，将基础设施视为一个版本化的组件并试着探索不可变服务器immutable server的概念。在后面的文章中，我们将了解如何使用开源工具来实现持续的基础设施。 + +![continuous infrastructure pipeline][2] + +*实践中的持续集成流程* + +这是我们熟悉的 CI，尽早发布、经常发布的循环流程。这个流程缺少一个关键的组件：基础设施。 + +突击小测试： + +* 你怎样创建和升级你的基础设施？ +* 你怎样控制和追溯基础设施的改变？ +* 你的基础设施是如何与你的业务进行匹配的？ +* 你是如何确保在正确的基础设施配置上进行测试的？ + +要回答这些问题，就要了解持续基础设施continuous infrastructure。把 CI 构建流程分为代码持续集成continuous integration code（CIc）和基础设施持续集成continuous integration infrastructure（CIi）来并行开发和构建代码和基础设施，再将两者融合到一起进行测试。把基础设施构建视为 CI 流程中的重要的一环。 + +![pipeline with infrastructure][4] + +*包含持续基础设施的 CI 流程* + +关于 CIi 定义的几个方面： + +1. 代码 + + 通过代码来创建基础设施架构，而不是通过安装。基础设施如代码Infrastructure as code（IaC）是使用配置脚本创建基础设施的现代最流行的方法。这些脚本遵循典型的编码和单元测试周期（请参阅下面关于 Terraform 脚本的示例）。 +2. 版本 + + IaC 组件在源码仓库中进行版本管理。这让基础设施的拥有了版本控制的所有好处：一致性，可追溯性，分支和标记。 +3. 管理 + + 通过编码和版本化的基础设施管理，你可以使用你所熟悉的测试和发布流程来管理基础设施的开发。 + +CIi 提供了下面的这些优势： + +1. 一致性Consistency + + 版本化和标记化的基础设施意味着你可以清楚的知道你的系统使用了哪些组件和配置。这建立了一个非常好的 DevOps 实践，用来鉴别和管理基础设施的一致性。 +2. 可重现性Reproducibility + + 通过基础设施的标记和基线，重建基础设施变得非常容易。想想你是否经常听到这个：“但是它在我的机器上可以运行！”现在，你可以在本地的测试平台中快速重现类似生产环境，从而将环境像变量一样在你的调试过程中删除。 +3. 可追溯性Traceability + + 你是否还记得曾经有过多少次寻找到底是谁更改了文件夹权限的经历，或者是谁升级了 `ssh` 包？代码化的、版本化的，发布的基础设施消除了临时性变更，为基础设施的管理带来了可追踪性和可预测性。 +4. 自动化Automation + + 借助脚本化的基础架构，自动化是下一个合乎逻辑的步骤。自动化允许你按需创建基础设施，并在使用完成后销毁它，所以你可以将更多宝贵的时间和精力用在更重要的任务上。 +5. 不变性Immutability + + CIi 带来了不可变基础设施等创新。你可以创建一个新的基础设施组件而不是通过升级（请参阅下面有关不可变设施的说明）。 + +持续基础设施是从运行基础环境到运行基础组件的进化。像处理代码一样，通过证实的 DevOps 流程来完成。对传统的 CI 的重新定义包含了缺少的那个 “i”，从而形成了连贯的 CD 。 + +**(CIc + CIi) = CI -> CD** + +### 基础设施如代码 （IaC） + +CIi 流程的一个关键推动因素是基础设施如代码infrastructure as code（IaC）。IaC 是一种使用配置文件进行基础设施创建和升级的机制。这些配置文件像其他的代码一样进行开发，并且使用版本管理系统进行管理。这些文件遵循一般的代码开发流程：单元测试、提交、构建和发布。IaC 流程拥有版本控制带给基础设施开发的所有好处，如标记、版本一致性，和修改可追溯。 + +这有一个简单的 Terraform 脚本用来在 AWS 上创建一个双层基础设施的简单示例，包括虚拟私有云（VPC）、弹性负载（ELB），安全组和一个 NGINX 服务器。[Terraform][5] 是一个通过脚本创建和更改基础设施架构和开源工具。 + +![terraform script][7] + +*Terraform 脚本创建双层架构设施的简单示例* + +完整的脚本请参见 [GitHub][8]。 + +### 不可变基础设施 + +你有几个正在运行的虚拟机，需要更新安全补丁。一个常见的做法是推送一个远程脚本单独更新每个系统。 + +要是不更新旧系统，如何才能直接丢弃它们并部署安装了新安全补丁的新系统呢？这就是不可变基础设施immutable infrastructure。因为之前的基础设施是版本化的、标签化的，所以安装补丁就只是更新该脚本并将其推送到发布流程而已。 + +现在你知道为什么要说基础设施在 CI 流程中特别重要了吗？ + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/17/11/continuous-infrastructure-other-ci + +作者：[Girish Managoli][a] +选题：[lujun9972](https://github.com/lujun9972) +译者：[Jamskr](https://github.com/Jamskr) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/gammay +[1]:/file/376916 +[2]:https://opensource.com/sites/default/files/images/life-uploads/figure1.jpg (continuous infrastructure pipeline in use) +[3]:/file/376921 +[4]:https://opensource.com/sites/default/files/images/life-uploads/figure2.jpg (CI pipeline with infrastructure) +[5]:https://github.com/hashicorp/terraform +[6]:/file/376926 +[7]:https://opensource.com/sites/default/files/images/life-uploads/figure3_0.png (sample terraform script) +[8]:https://github.com/terraform-providers/terraform-provider-aws/tree/master/examples/two-tier diff --git a/published/201812/20171111 A CEOs Guide to Emacs.md b/published/201812/20171111 A CEOs Guide to Emacs.md new file mode 100644 index 0000000000..4a92e5710b --- /dev/null +++ b/published/201812/20171111 A CEOs Guide to Emacs.md @@ -0,0 +1,286 @@ +CEO 的 Emacs 秘籍 +=========== + +几年前，不，是几十年前，我就在用 Emacs。不论是码代码、编写文档，还是管理邮件和日程，我都用这个编辑器，或者是说操作系统，而且我还乐此不疲。许多年过去了，我也转向了其他更新、更好的工具。结果，就连最基本的文件浏览，我都已经忘了在不用鼠标的情况下该怎么操作。大约三个月前，我意识到我在应用程序和计算机之间切换上耗费了大量的时间，于是我决定再次使用 Emacs。这是个很正确的决定，原因有以下几个。其中包括用 `.emacs` 和 Dropbox 来搭建一个良好的、可移植的环境的一些技巧。 + +对于那些还没用过 Emacs 的人来说，Emacs 会让你爱恨交加。它有点像一个房子大小的鲁布·戈德堡机械Rube Goldberg machine，乍一看，它具备烤面包机的所有功能。这听起来不像是一种认可，但关键词是“乍一看”。一旦你了解了 Emacs，你就会意识到它其实是一台可以当发动机用的热核烤面包机……好吧，只是指文本处理的所有事情。当考虑到你计算机的使用周期在很大程度上都是与文本有关时，这是一个相当大胆的声明。大胆，但却是真的。 + +也许对我来说更重要的是，Emacs 是我曾经使用过的一个应用，并让我觉得我真正的拥有它，而不是把我塑造成一个匿名的“用户”，就好像位于 [Soma][30]（LCTT 译注：旧金山的一个街区）或雷蒙德（LCTT 译注：微软总部所在地）附近某个高档办公室的产品营销部门把钱作为明确的目标一样。现代生产力和创作应用程序（如 Pages 或 IDE）就像碳纤维赛车，它们装备得很好，也很齐全。而 Emacs 就像一盒经典的 [Campagnolo][31] （LCTT 译注：世界上最好的三个公路自行车套件系统品牌之一）零件和一个漂亮的自行车牵引式钢框架，但缺少曲柄臂和刹车杆，你必须在网上某个小众文化中找到它们。前者更快而且很完整，后者是无尽的快乐或烦恼的源泉，当然这取决于你自己，而且这种快乐或烦恼会伴随到你死。我就是那种在找到一堆老古董或用 `Emacs Lisp` 配置编辑器时会感到高兴的人，具体情况因人而异。 + +![1933 steel bicycle](https://www.fugue.co/hubfs/Imported_Blog_Media/bicycle-1.jpg) + +*一辆我还在骑的 1933 年产的钢制自行车。你可以看看框架管差别： [https://www.youtube.com/watch?v=khJQgRLKMU0][6]* + +这可能给人一种 Emacs 已经过气或过时的印象。然而并不是，Emacs 是强大和永恒的，只要你耐心地去理解它的一些规则。Emacs 的规则很另类，也很奇怪，但其中的逻辑却引人注目，且魅力十足。对于我来说， Emacs 更像是未来而不是过去。就像牵引式钢框架在未来几十年里将会变得好用和舒适，而神奇的碳纤维自行车将会被扔进垃圾场，在撞击中粉碎一样，Emacs 也将会作为一种在最新的流行应用早已被遗忘的时候的好用的工具继续存在这里。 + +使用 Lisp 代码来构建个人工作环境，并将这个恰到好处的环境移植到任何计算机，如果这种想法打动了你，那么你将会爱上 Emacs。如果你喜欢很潮、很炫的，又不想投入太多时间和精力的情况下就能直接工作的话，那么 Emacs 可能不适合你。我已经不再写代码了（除了 Ludwig 和 Emacs Lisp），但是 Fugue 公司的很多工程师都使用 Emacs 来提高码代码的效率。我公司有 30% 的工程师用 Emacs，40% 用 IDE 和 30% 的用 vim。但这篇文章是写给 CEO 和其他[精英][32]Pointy-Haired Bosses（PHB[^1] ）（以及对 Emacs 感兴趣的人）的，所以我将解释或者说辩解我为什么喜欢它以及我如何使用它。同时我也希望我能介绍清楚，从而让你有个良好的体验，而不是花上几个小时去 Google。 + +### 恒久优势 + +使用 Emacs 带来的长期优势是让生活更轻松。与最后的收获相比，最开始的付出完全值得。想想这些： + +#### 简单高效 + +Org 模式本身就值得花时间，但如果你像我一样，你通常要处理十几份左右的文件 —— 从博客帖子到会议事务清单，再到员工评估。在现代计算世界中，这通常意味着要使用多个应用程序，所有这些程序都有不同的用户界面、保存方式、排序和搜索方式。结果就是你需要不断转换思维环境，记住各种细节。我讨厌在程序间切换，这是在强人所难，因为这是个不完整界面模型[^2] ，并且我讨厌记住本该由计算机记住的东西。在单个环境下，Emacs 对 PHB 甚至比对于程序员更高效，因为程序员更多时候只需要专注于一个程序。转换思维环境的成本比表面上的要更高。操作系统和应用程序厂商已经构建了各种界面，以分散我们对这一现实的注意力。如果你是技术人员，通过快捷键（`M-:`）来访问功能强大的[语言解释器][33]会方便的多[^3] 。 + +许多应用程序可以全天全屏地用于编辑文本。但Emacs 是唯一的，因为它既是编辑器也是 Emacs Lisp 解释器。从本质上来说，你工作时只要用电脑上的一两个键就能完成。如果你略懂编程的话，就会发现这代表着你可以在 Emacs 中做 _任何事情_。一旦你在内存中存储了这些指令，你的电脑就可以在工作时几乎实时地为你提供高效的运转。你不会想用 Emacs Lisp 来重建 Excel，因为只要用简单的一两行代码就能实现 Excel 中大多数的功能。比如说我要处理数字，我更有可能转到 scratch 缓冲区，编写一些代码，而不是打开电子表格。即便是要写一封比较大的邮件时，我通常也会先在 Emacs 中写完，然后再复制粘贴到邮件客户端中。当你可以流畅的书写时，为什么要去切换呢？你可以先从一两个简单的算术开始，随着时间的推移，你可以很容易的在 Emacs 中添加你所需要处理的计算。这在应用程序中可能是独一无二的，同时还提供了让为其他的人创造的丰富特性。还记得艾萨克·阿西莫夫书中那些神奇的终端吗？ Emacs 是我所遇到的最接近它们的东西[^4] 。我决定不再用什么应用程序来做这个或那个。相反，我只是工作。拥有一个伟大的工具并致力于此，这才是真正的动力和效率。 + +#### 静中造物 + +拥有所发现的最好的文本编辑功能的最终结果是什么？有一群人在做各种各样有用的补充吗？发挥了 Lisp 键盘的全部威力了吗？我用 Emacs 来完成所有的创作性工作，音乐和图片除外。 + +我办公桌上有两个显示器。其中一块竖屏是将 Emacs 全天全屏显示，另一个显示浏览器，用来搜索和阅读，我通常也会打开一个终端。我将日历、邮件等放在 OS X 的另一个桌面上，当我使用 Emacs 时，这个桌面会隐藏起来，同时我也会关掉所有通知。这样就能让我专注于我手头上在做的事了。我发现，越是先进的 UI 应用程序，消除干扰越是不可能，因为这些应用程序致力于提供帮助和易用性。我不需要经常被提醒该如何操作，我已经做了成千上万次了，我真正需要的是一张干净整洁的白纸用来思考。也许因为年龄和自己的“恶习”，我不太喜欢处在嘈杂的环境中，但我认为这值得一试。看看在你电脑环境中有一些真正的宁静是怎样的。当然，现在很多应用程序都有隐藏界面的模式，谢天谢地，苹果和微软现在都有了真正意义上的全屏模式。但是，没有并没有应用程序可以强大到足以“处理”大多数事务。除非你整天写代码，或者像出书一样，处理很长的文档，否则你仍然会面临其他应用程序的干扰。而且，大多数现代应用程序似乎同时显得自视甚高，缺乏功能和可用性[^5] 。比起 office 桌面版，我更讨厌它的在线版。 + +![](https://www.fugue.co/hubfs/Imported_Blog_Media/desktop-1.jpg) + +*我的桌面布局， Emacs 在左边* + +但是沟通呢？创造和沟通之间的差别很大。当我将这两件事在不同时间段处理时，我的效率会更高。我们 Fugue 公司使用 Slack，痛并快乐着。我把 Slack 和我的日历、电子邮件放在一个即时通讯的桌面上，这样，当我正在做事时，我就能够忽略所有的聊天信息了。虽然只要一个 Slackstorm 或一封风投或董事会董事的电子邮件，就能让我立刻丢掉手头工作。但是，大多数事情通常可以等上一两个小时。 + +#### 普适恒久 + +第三个原因是，我发现 Emacs 比其它的环境更有优势的是，你可以很容易地用它来处理事务。我的意思是，你所需要的只是通过类似于 Dropbox 的网站同步一两个目录，而不是让大量的应用程序以它们自己的方式进行交互和同步。然后，你可以在任何你已经精心打造了适合你的目的的套件的环境中工作了。我在 OS X、Windows，或有时在 Linux 都是这样做的。它非常简单可靠。这种功能很有用，以至于我害怕处理 Pages、Google Docs、Office 或其他类型的文件和应用程序，这些文件和应用程序会迫使我回到文件系统或云中的某个地方去寻找。 + +限制在计算机上永久存储的因素是文件格式。假设人类已经解决了存储问题[^6] ，随着时间的推移，我们面临的问题是我们能否够继续访问我们创建的信息。文本文件是保存时间最久的格式。你可以用 Emacs 轻松地打开 1970 年的文本文件。然而对于 Office 应用程序却并非如此。同时文本文件要比 Office 应用程序数据文件小得多，也要好的多。作为一个数码背包迷，作为一个在脑子里一闪而过就会做很多小笔记的人，拥有一个简单、轻便、永久、随时可用的东西对我来说很重要。 + +如果你准备尝试 Emacs，请继续读下去！下面的部分不是完整的教程，但是在读完后，就可以动手操作了。 + +### 驾驭之道 —— 专业定制 + +所有这些强大、精神上的平静和安宁的代价是，Emacs 有一个陡峭的学习曲线，它的一切都与你以前所习惯的不同。一开始，这会让你觉得你是在浪费时间在一个过时和奇怪的应用程序上，就好像穿越到过去。这有点像你只开过车，却要你去学骑自行车[^7] 。 + +#### 类型抉择 + +我用的是来自 GNU 的 OS X 和 Windows 的通用版本的 Emacs。你可以在 [http://emacsformacos.com/][35] 获取 OS X 版本，在 [http://www.gnu.org/software/emacs/][37] 获取 Windows 版本。市面上还有很多其他版本，尤其是 Mac 版本，但我发现，要做一些功能强大的东西（涉及到 Lisp 和许多模式），学习曲线要比实际操作低得多。下载，然后我们就可以开始了[^8] ！ + +#### 驾驭之始 + +在本文中，我将使用 Emacs 的按键和组合键约定。`C` 表示 `Control` 键，`M` 表示 `meta`（通常是 `Alt` 或 `Option` 键），以及用于组合键的连字符。因此，`C-h t` 表示同时按下 `Control` 和 `h` 键，然后释放，再按下 `t`。这个组合快捷键会指向一个教程，这是你首先要做的一件事。 + +不要使用方向键或鼠标。它们可以工作，但是你应该给自己一周的时间来使用 Emacs 教程中的原生的导航命令。一旦你这些命令变为了肌肉记忆，你可能就会乐在其中，无论到哪里，你都会非常想念它们。这个 Emacs 教程在介绍它们方面做得很好，但是我将进行总结，所以你不需要阅读全部内容。最无聊的是，不用方向键，用 `C-b` 向前移动，用 `C-f` 向后移动，上一行用 `C-p`，下一行用 `C-n`。你可能会想：“我用方向键就很好，为什么还要这样做？” 有几个原因。首先，你不需要从主键盘区将你的手移开。第二，使用 `Alt`（或用 Emacs 的说法 `Meta`）键来向前或向后在单词间移动。显而易见这样更方便。第三，如果想重复某个命令，可以在命令前面加上一个数字。在编辑文档时，我经常使用这种方法，通过估计向后移动多少个单词或向上或向下移动多少行，然后按下 `C-9 C-p` 或 `M-5 M-b` 之类的快捷键。其它真正重要的导航命令基于开头用 `a` 和结尾用 `e`。在行中使用 `C-a|e`，在句中使用 `M-a|e`。为了让句中的命令正常工作，需要在句号后增加两个空格，这同时提供了一个有用的特性，并消除了脑中一个过时的[观点][38]。如果需要将文档导出到单个空间[发布环境][39]，可以编写一个宏来执行此操作。 + +Emacs 所附带的教程很值得去看。对于真正缺乏耐心的人，我将介绍一些重要的命令，但那个教程非常有用。记住：用 `C-h t` 进入教程。 + +#### 驾驭之复制粘贴 + +你可以把 Emacs 设为 CUA 模式，这将会以熟悉的方式工作来操作复制粘贴，但是原生的 Emacs 方法更好，而且你一旦学会了它，就很容易。你可以使用 `Shift` 和导航命令来标记区域（如同选择）。所以 `C-F` 是选中光标前的一个字符，等等。亦可以用 `M-w` 来复制，用 `C-w` 剪切，然后用 `C-y` 粘贴。这些实际上叫做删除killing和召回yanking，但它非常类似于剪切和粘贴。在删除中还有一些小技巧，但是现在，你只需要关注剪切、复制和粘贴。如果你开始尝试了，那么 `C-x u` 是撤销。 + +#### 驾驭之 Ido 模式 + +相信我，Ido 会让文件的工作变得很简单。通常，你在 Emacs 中处理文件不需要使用一个单独的访达或文件资源管理器的窗口。相反，你可以用编辑器的命令来创建、打开和保存文件。如果没有 Ido 的话，这将有点麻烦，所以我建议你在学习其他之前安装好它。 Ido 是 Emacs 的 22 版时开始出现的，但是需要对你的 `.emacs` 文件做一些调整，来确保它一直开启着。这是个配置环境的好理由。 + +Emacs 中的大多数功能都表现在模式上。要安装指定的模式，需要做两件事。嗯，一开始你需要做一些额外的事情，但这些只需要做一次，然后再做这两件事。那么，这件额外的事情是你需要一个单独的位置来放置所有 Emacs Lisp 文件，并且你需要告诉 Emacs 这个位置在哪。我建议你在 Dropbox 上创建一个单独的目录，那是你 Emacs 主目录。在这里，你需要创建一个 `.emacs` 文件和 `.emacs.d` 目录。在 `.emacs.d` 目录下，创建一个 `lisp` 的目录。就像这样: + +``` +home +| ++.emacs +| +-.emacs.d + | + -lisp +``` + +你可以将 `.el` 文件，比如说模式文件，放到 `home/.emacs.d/lisp` 目录下，然后在你的 `.emacs` 文件中添加以下代码来指明该路径： + +``` +(add-to-list 'load-path "~/.emacs.d/lisp/") +``` + +Ido 模式是 Emacs 自带的，所以你不需要在你的 `lisp` 目录中放这个 `.el` 文件，但你仍然需要添加上面代码，因为下面的介绍会使用到它. + +#### 驾驭之符号链接 + +等等，这里写的 `.emacs` 和 `.emacs.d` 都是存放在你的主目录下，但我们把它们放到了 Dropbox 的某些愚蠢的文件夹！对，这就让你的环境在任何地方都很容易使用。把所有东西都保存在 Dropbox 上，并做符号链接到 `~` 下的 `.emacs` 、`.emacs.d` 和你的主要存放文档的目录。在 OS X 上，使用 `ln -s` 命令非常简单，但在 Windows 上却很麻烦。幸运的是，Emacs 提供了一种简单的方法来替代 Windows 上的符号链接，Windows 的 `HOME` 环境变量。转到 Windows 的环境变量（Windows 10,你可以按 Windows 键然后输入 “环境变量” 来搜索，这是 Windows 10 最好的地方了)，在你的帐户下创建一个指向你在 Dropbox 中 Emacs 的文件夹的 `HOME` 环境变量。如果你想方便地浏览 Dropbox 之外的本地文件，你可能想在你的实际主目录下建立一个到 Dropbox 下 Emacs 主目录的符号链接。 + +至此，你已经完成了在任意机器上指向你的 Emacs 配置和文件所需的技巧。如果你买了一台新电脑，或者用别人的电脑一小时或一天，你就可以得到你的整个工作环境。第一次操作起来似乎有点难，但是一旦你知道你在做什么，就（最多）只需要 10 分钟。 + +但我们现在是在配置 Ido …… + +按下 `C-x` `C-f` 然后输入 `~/.emacs` 和两次回车来创建 `.emacs` 文件，将下面几行添加进去: + +``` +;; set up ido mode +(require `ido) +(setq ido-enable-flex-matching t) +(setq ido-everywhere t) +(ido-mode 1) +``` + +在 `.emacs` 窗口开着的时候，执行 `M-x evaluate-buffer` 命令。如果某处弄错了的话，将得到一个错误，或者你将得到 Ido。Ido 改变了在 minibuffer 中操作文件操方式。关于这个有一篇比较好的文档，但是我也会指出一些技巧。有效地使用 `~/`；你可以在 minibuffer 的任何地方输入 `~/`，它就会跳转到主目录。这就意味着，你应该让你的大部分东西就近的放在主目录下。我用 `~/org` 目录来保存所有非代码的东西，用 `~/code` 保存代码。一旦你进入到正确的目录，通常会拥有一组具有不同扩展名的文件，特别是当你使用 Org 模式并从中发布的话。你可以输入 `.` 和想要的扩展名，无论你的在文件名的什么位置，Ido 都会将选择限制在具有该扩展名的文件中。例如，我在 Org 模式下写这篇博客，所以该文件是： + +``` +~/org/blog/emacs.org +``` + +我偶尔也会用 Org 模式发布成 HTML 格式，所以我将在同一目录下得到 `emacs.html` 文件。当我想打开该 Org 文件时，我会输入： + +``` +C-x C-f ~/o[RET]/bl[RET].or[RET] +``` + +其中 `[RET]` 是我使用 `Ido` 模式的自动补全而按下的回车键。所以，这只需要按 12 个键，如果你习惯了的话， 这将比打开访达或文件资源管理器再用鼠标点要节省 _很_ 多时间。 Ido 模式很有用，而这只是操作 Emacs 的一种实用模式而已。下面让我们去探索一些其它对完成工作很有帮助的模式吧。 + +#### 驾驭之字体风格 + +我推荐在 Emacs 中使用漂亮的字体族。它们可以使用不同的括号、0 和其他字符进行自定义。你可以在字体文件本身中构建额外的行间距。我推荐 1.5 倍的行间距，并在代码和数据中使用不等宽字体。写作中我用 `Serif` 字体，它有一种紧凑但时髦的感觉。你可以在 [http://input.fontbureau.com/][40] 上找到它们，在那里你可以根据自己的喜好进行定制。你可以使用 Emacs 中的菜单手动设置字体，但这会将代码保存到你的 `.emacs` 文件中，如果你使用多个设备，你可能需要一些不同的设置。我将我的 `.emacs` 设置为根据使用的机器的名称来相应配置屏幕。代码如下： + +``` +;; set up fonts for different OSes. OSX toggles to full screen. +(setq myfont "InputSerif") +(cond +((string-equal system-name "Sampo.local") + (set-face-attribute 'default nil :font myfont :height 144) + (toggle-frame-fullscreen)) +((string-equal system-name "Morpheus.local") + (set-face-attribute 'default nil :font myfont :height 144)) +((string-equal system-name "ILMARINEN") + (set-face-attribute 'default nil :font myfont :height 106)) +((string-equal system-name "UKKO") + (set-face-attribute 'default nil :font myfont :height 104))) +``` + +你应该将 Emacs 中的 `system-name` 的值替换成你通过 `(system-name)` 得到的值。注意，在 Sampo （我的 MacBook）上，我还将 Emacs 设置为全屏。我也想在 Windows 实现这个功能，但是 Windows 和 Emacs 好像互相嫌弃对方，当我尝试配置时，它总是不稳定。相反，我只能在启动后手动全屏。 + +我还建议去掉 Emacs 中的上世纪 90 年代出现的难看工具栏，当时比较流行在应用程序中使用工具栏。我还去掉了一些其它的“电镀层”，这样我就有了一个简单、高效的界面。把这些加到你的 `.emacs` 的文件中来去掉工具栏和滚动条，但要保留菜单（在 OS X 上，它将被隐藏，除非你将鼠标到屏幕顶部）： + +``` +(if (fboundp 'scroll-bar-mode) (scroll-bar-mode -1)) +(if (fboundp 'tool-bar-mode) (tool-bar-mode -1)) +(if (fboundp 'menu-bar-mode) (menu-bar-mode 1)) +``` + +#### 驾驭之 Org 模式 + +我基本上是在 Org 模式下处理工作的。它是我创作文档、记笔记、列任务清单以及 90% 其他工作的首选环境。Org 模式是笔记和待办事项列表的组合工具，最初是由一个在会议中使用笔记本电脑的人构想出来的。我反对在会议中使用笔记本电脑，自己也不使用，所以我的用法与他的有些不同。对我来说，Org 模式主要是一种处理结构中内容的方式。在 Org 模式中有标题和副标题等，它们的作用就像一个大纲。Org 模式允许你展开或隐藏大纲树，还可以重新排列该树。这正合我意，并且我发现用这种方式使用它是一种乐趣。 + +Org 模式也有很多让生活愉快的小功能。例如，脚注处理非常好，LaTeX/PDF 输出也很好。Org 模式能够根据所有文档中的待办事项生成议程，并能很好地将它们与日期/时间联系起来。我不把它用在任何形式的外部任务上，这些任务都是在一个共享的日历上处理的，但是在创建事物和跟踪我未来需要创建的东西时，它是无价的。安装它，你只要将 `org-mode.el` 放到你的 `lisp` 目录下。如果你想要它基于文档的结构进行缩进并在打开时全部展开的话，在你的 `.emacs` 文件中添加如下代码： + +``` +;; set up org mode +(setq org-startup-indented t) +(setq org-startup-folded "showall") +(setq org-directory "~/org") +``` + +最后一行是让 Org 模式知道在哪里查找要包含在议程和其他事情中的文件。我把 Org 模式保存在我的主目录中，也就是说，像前面介绍的一样，它是 Dropbox 目录的一个符号链接。 + +我有一个总是在缓冲区中打开的 `stuff.org` 文件。我把它当作记事本。Org 模式使得提取待办事项和有期限的事情变得很容易。当你能够内联 Lisp 代码并在需要计算它时，它特别有用。拥有包含内容的代码非常方便。同样，你可以使用 Emacs 访问实际的计算机，这是一种解放。 + +##### 用 Org 模式进行发布 + +我关心的是文档的外观及格式。我刚开始工作时是个设计师，而且我认为信息可以，也应该表现得清晰和美丽。Org 模式对将 LaTeX 生成 PDF 支持的很好，LaTeX 虽然也有学习曲线，但是很容易处理一些简单的事务。 + +如果你想使用字体和样式，而不是典型的 LaTeX 字体和样式，你需要做些事。首先，你要用到 XeLaTeX，这样就可以使用普通的系统字体，而不是 LaTeX 的特殊字体。接下来，你需要将以下代码添加到 `.emacs` 中： + +``` +(setq org-latex-pdf-process + '("xelatex -interaction nonstopmode %f" + "xelatex -interaction nonstopmode %f")) +``` + +我把这个放在 `.emacs` 中 Org 模式配置部分的末尾，使文档变得更整洁。这让你在从 Org 模式发布时可以使用更多格式化选项。例如，我经常使用： + +``` +#+LaTeX_HEADER: \usepackage{fontspec} +#+LATEX_HEADER: \setmonofont[Scale=0.9]{Input Mono} +#+LATEX_HEADER: \setromanfont{Maison Neue} +#+LATEX_HEADER: \linespread{1.5} +#+LATEX_HEADER: \usepackage[margin=1.25in]{geometry} + +#+TITLE: Document Title Here +``` + +这些都可以在 `.org` 文件中找到。我们的公司规定的正文字体是 `Maison Neue`，但你也可以在这写上任何适当的东西。我很是抵制 `Maison Neue`，因为这是一种糟糕的字体，任何人都不应该使用它。 + +这个文件是一个使用该配置输出为 PDF 的实例。这就是开箱即用的 LaTeX 一样。在我看来这还不错，但是字体很平淡，而且有点奇怪。此外，如果你使用标准格式，人们会觉得他们正在阅读的东西是、或者假装是一篇学术论文。别怪我没提醒你。 + +#### 驾驭之 Ace Jump 模式 + +这只是一个辅助模式，而不是一个主模式，但是你也需要它。其工作原理有点像之前提到的 Jef Raskin 的 Leap 功能[^9] 。 按下 `C-c C-SPC`，然后输入要跳转到单词的第一个字母。它会高亮显示所有以该字母开头的单词，并将其替换为字母表中的字母。你只需键入所需位置的字母，光标就会跳转到该位置。我常将它作为导航键或是用来检索。将 `.el` 文件下到你的 `lisp` 目录下，并在 `.emacs` 文件添加如下代码： + +``` +;; set up ace-jump-mode +(add-to-list 'load-path "which-folder-ace-jump-mode-file-in/") +(require 'ace-jump-mode) +(define-key global-map (kbd "C-c C-SPC" ) 'ace-jump-mode) +``` + +### 待续 + +本文已经够详细了，你能在其中得到你所想要的。我很想知道除编程之外（或用于编程）Emacs 的使用情况，及其是否高效。在我使用 Emacs 的过程中，可能存在一些自作聪明的老板式想法，如果你能指出来，我将不胜感激。之后，我可能会写一些更新来介绍其它特性或模式。我很确定我将会向你展示如何在 Emacs 和 Ludwig 模式下使用 Fugue，因为我会将它发展成比代码高亮更有用的东西。更多想法，请在 Twitter 上 [@fugueHQ][41] 。 + +### 脚注 + +[^1]: 如果你是位精英，但从没涉及过技术方面，那么 Emacs 并不适合你。对于少数的人来说，Emacs 可能会为他们开辟一条通往计算机技术方面的道路，但这只是极少数。如果你知道怎么使用 Unix 或 Windows 的终端，或者曾编辑过 dotfile，或者说你曾写过一点代码的话，这对使用 Emacs 有很大的帮助。 + +[^2]: 参考链接： http://archive.wired.com/wired/archive/2.08/tufte.html + +[^3]: 我主要是在写作时使用这个模式来进行一些运算。比如说，当我在给一个新雇员写一封入职信时，我想要算这封入职信中有多少个选项。由于我在我的 `.emacs` 为 outstanding-shares 定义了一个变量，所以我只要按下 `M-:` 然后输入 `(* .001 outstanding-shares)` 就能再无需打开计算器或电子表格的情况下得到精度为 0.001 的结果。我使用了 _大量_ 的变量来避免程序间切换。 + +[^4]: 缺少的部分是 web。有个名为 eww 的 Emacs 网页浏览器能够让你在 Emacs 中浏览网页。我用的就是这个，因为它既能拦截广告（LCTT 译注：实质上是无法显示，/laugh），同时也在可读性方面为 web 开发者消除了大多数差劲的选项。这个其实有点类似于 Safari 的阅读模式。不幸的是，大部分网站都有很多令人讨厌的繁琐的东西以及难以转换为文本的导航， + +[^5]: 易用性和易学性这两者经常容易被搞混。易学性是指学习使用工具的难易程度。而易用性是指工具高效的程度。通常来说，这是要差别的，就想鼠标和菜单栏的差别一样。菜单栏很容易学会，但是却不怎么高效，以致于早期会存在一些键盘的快捷键。除了在 GUI 方面上，Raskin 在很多方面上的观点都很正确。如今，操作系统正在将一些合适的搜索映射到键盘的快捷键上。比如说在 OS X 和 Windows 上，我默认的导航方式就是搜索。Ubuntu 的搜索做的很差劲，如同它的 GUI 一样差劲。 + +[^6]: 在有网的情况下，[AWS S3][42] 是解决文件存储问题的有效方案。数万亿个对象存在 S3 中，但是从来没有遗失过。大部分提供云存储的服务都是在 S3 上或是模拟 S3 构建的。没人能够拥有 S3 一样的规模，所以我将重要的文件通过 Dropbox 存储在上面。 + +[^7]: 目前，你可能会想：“这个人和自行车有什么关系？”……我在各个层面上都喜欢自行车。自行车是迄今为止发明的最具机械效率的交通工具。自行车可以是真正美丽的事物。而且，只要注意点的话，自行车可以用一辈子。早在 2001 年，我曾向 Rivendell Bicycle Works 订购了一辆自行车，现在我每次看到那辆自行车依然很高兴，自行车和 Unix 是我接触过的最好的两个发明。对了，还有 Emacs。 + +[^8]: 这个网站有一个很棒的 Emacs 教程，但不是这个。当我浏览这个页面时，我确实得到了一些对获取高效的 Emacs 配置很重要的知识，但无论怎么说，这都不是个替代品。 + +[^9]: 20 世纪 80 年代，Jef Raskin 与 Steve Jobs 在 Macintosh 项目上闹翻后， Jef Raskin 又设计了 [Canon Cat 计算机][43]。这台 Cat 计算机是以文档为中心的界面（所有的计算机都应如此），并以一种全新的方式使用键盘，你现在可以用 Emacs 来模仿这种键盘。如果现在有一台现代的，功能强大的 Cat 计算机并配有一个高分辨的显示器和 Unix 系统的话，我立马会用 Mac 来换。[https://youtu.be/o_TlE_U_X3c?t=19s][28] + +-------------------------------------------------------------------------------- + +via: https://blog.fugue.co/2015-11-11-guide-to-emacs.html + +作者：[Josh Stella][a] +译者：[oneforalone](https://github.com/oneforalone) +校对：[wxy](https://github.com/wxy), [oneforalone](https://github.com/oneforalone) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://blog.fugue.co/authors/josh.html +[1]:https://blog.fugue.co/2013-10-16-vpc-on-aws-part3.html +[2]:https://blog.fugue.co/2013-10-02-vpc-on-aws-part2.html +[3]:http://ww2.fugue.co/2017-05-25_OS_AR_GartnerCoolVendor2017_01-LP-Registration.html +[4]:https://blog.fugue.co/authors/josh.html +[5]:https://twitter.com/joshstella +[6]:https://www.youtube.com/watch?v=khJQgRLKMU0 +[7]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#phb +[8]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#tufte +[9]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#interpreter +[10]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#eww +[11]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#usability +[12]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#s3 +[13]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#bicycles +[14]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#nottutorial +[15]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#canoncat +[16]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#phbOrigin +[17]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#tufteOrigin +[18]:http://archive.wired.com/wired/archive/2.08/tufte.html +[19]:http://archive.wired.com/wired/archive/2.08/tufte.html +[20]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#interpreterOrigin +[21]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#ewwOrigin +[22]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#usabilityOrigin +[23]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#s3Origin +[24]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#bicyclesOrigin +[25]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#nottutorialOrigin +[26]:https://blog.fugue.co/2015-11-11-guide-to-emacs.html?utm_source=wanqu.co&utm_campaign=Wanqu+Daily&utm_medium=website#canoncatOrigin +[27]:https://youtu.be/o_TlE_U_X3c?t=19s +[28]:https://youtu.be/o_TlE_U_X3c?t=19s +[29]:https://blog.fugue.co/authors/josh.html +[30]:http://www.huffingtonpost.com/zachary-ehren/soma-isnt-a-drug-san-fran_b_987841.html +[31]:http://www.campagnolo.com/US/en +[32]:http://www.businessinsider.com/best-pointy-haired-boss-moments-from-dilbert-2013-10 +[33]:http://www.webopedia.com/TERM/I/interpreter.html +[34]:http://emacsformacosx.com/ +[35]:http://emacsformacosx.com/ +[36]:http://www.gnu.org/software/emacs/ +[37]:http://www.gnu.org/software/emacs/ +[38]:http://www.huffingtonpost.com/2015/05/29/two-spaces-after-period-debate_n_7455660.html +[39]:http://practicaltypography.com/one-space-between-sentences.html +[40]:http://input.fontbureau.com/ +[41]:https://twitter.com/fugueHQ +[42]:https://baike.baidu.com/item/amazon%20s3/10809744?fr=aladdin +[43]:https://en.wikipedia.org/wiki/Canon_Cat diff --git a/published/201812/20171129 TLDR pages Simplified Alternative To Linux Man Pages.md b/published/201812/20171129 TLDR pages Simplified Alternative To Linux Man Pages.md new file mode 100644 index 0000000000..bca48001bf --- /dev/null +++ b/published/201812/20171129 TLDR pages Simplified Alternative To Linux Man Pages.md @@ -0,0 +1,106 @@ +TLDR 页：Linux 手册页的简化替代品 +============== + +[![](https://fossbytes.com/wp-content/uploads/2017/11/tldr-page-ubuntu-640x360.jpg "tldr page ubuntu")][22] + +在终端上使用各种命令执行重要任务是 Linux 桌面体验中不可或缺的一部分。Linux 这个开源操作系统拥有[丰富的命令][23]，任何用户都无法全部记住所有这些命令。而使事情变得更复杂的是，每个命令都有自己的一组带来丰富的功能的选项。 + +为了解决这个问题，人们创建了[手册页][12]man page，（手册 —— man 是 manual 的缩写）。首先，它是用英文写成的，包含了大量关于不同命令的深入信息。有时候，当你在寻找命令的基本信息时，它就会显得有点庞杂。为了解决这个问题，人们创建了[TLDR 页][13]。 + +### 什么是 TLDR 页？ + +TLDR 页的 GitHub 仓库将其描述为简化的、社区驱动的手册页集合。在实际示例的帮助下，努力让使用手册页的体验变得更简单。如果还不知道，TLDR 取自互联网的常见俚语：太长没读Too Long Didn’t Read。 + +如果你想比较一下，让我们以 `tar` 命令为例。 通常，手册页的篇幅会超过 1000 行。`tar` 是一个归档实用程序，经常与 `bzip` 或 `gzip` 等压缩方法结合使用。看一下它的手册页： + +[![tar man page](https://fossbytes.com/wp-content/uploads/2017/11/tar-man-page.jpg)][14] + +而另一方面，TLDR 页面让你只是浏览一下命令，看看它是如何工作的。 `tar` 的 TLDR 页面看起来像这样，并带有一些方便的例子 —— 你可以使用此实用程序完成的最常见任务： + +[![tar tldr page](https://fossbytes.com/wp-content/uploads/2017/11/tar-tldr-page.jpg)][15] + +让我们再举一个例子，向你展示 TLDR 页面为 `apt` 提供的内容： + +[![tldr-page-of-apt](https://fossbytes.com/wp-content/uploads/2017/11/tldr-page-of-apt.jpg)][16] + +如上，它向你展示了 TLDR 如何工作并使你的生活更轻松，下面让我们告诉你如何在基于 Linux 的操作系统上安装它。 + +### 如何在 Linux 上安装和使用 TLDR 页？ + +最成熟的 TLDR 客户端是基于 Node.js 的，你可以使用 NPM 包管理器轻松安装它。如果你的系统上没有 Node 和 NPM，请运行以下命令： + +``` +sudo apt-get install nodejs +sudo apt-get install npm +``` + +如果你使用的是 Debian、Ubuntu 或 Ubuntu 衍生发行版以外的操作系统，你可以根据自己的情况使用`yum`、`dnf` 或 `pacman`包管理器。 + +现在，通过在终端中运行以下命令，在 Linux 机器上安装 TLDR 客户端： + +``` +sudo npm install -g tldr +``` + +一旦安装了此终端实用程序，最好在尝试之前更新其缓存。 为此，请运行以下命令： + +``` +tldr --update +``` + +执行此操作后，就可以阅读任何 Linux 命令的 TLDR 页面了。 为此，只需键入： + +``` +tldr +``` + +[![tldr kill command](https://fossbytes.com/wp-content/uploads/2017/11/tldr-kill-command.jpg)][17] + +你还可以运行其[帮助命令](https://github.com/tldr-pages/tldr-node-client)，以查看可与 TLDR 一起使用的各种参数，以获取所需输出。 像往常一样，这个帮助页面也附有例子。 + +### TLDR 的 web、Android 和 iOS 版本 + +你会惊喜地发现 TLDR 页不仅限于你的 Linux 桌面。 相反，它也可以在你的 Web 浏览器中使用，可以从任何计算机访问。 + +要使用 TLDR Web 版本，请访问 [tldr.ostera.io][18] 并执行所需的搜索操作。 + +或者，你也可以下载 [iOS][19] 和 [Android][20] 应用程序，并随时随地学习新命令。 + +[![tldr app ios](https://fossbytes.com/wp-content/uploads/2017/11/tldr-app-ios.jpg)][21] + +你觉得这个很酷的 Linux 终端技巧很有意思吗？ 请尝试一下，让我们知道您的反馈。 + +-------------------------------------------------------------------------------- + +via: https://fossbytes.com/tldr-pages-linux-man-pages-alternative/ + +作者：[Adarsh Verma][a] +译者：[wxy](https://github.com/wxy) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://fossbytes.com/author/adarsh/ +[1]:https://fossbytes.com/watch-star-wars-command-prompt-via-telnet/ +[2]:https://fossbytes.com/use-stackoverflow-linux-terminal-mac/ +[3]:https://fossbytes.com/single-command-curl-wttr-terminal-weather-report/ +[4]:https://fossbytes.com/how-to-google-search-in-command-line-using-googler/ +[5]:https://fossbytes.com/check-bitcoin-cryptocurrency-prices-command-line-coinmon/ +[6]:https://fossbytes.com/review-torrench-download-torrents-using-terminal-linux/ +[7]:https://fossbytes.com/use-wikipedia-termnianl-wikit/ +[8]:http://www.facebook.com/sharer.php?u=https%3A%2F%2Ffossbytes.com%2Ftldr-pages-linux-man-pages-alternative%2F +[9]:https://twitter.com/intent/tweet?text=TLDR+pages%3A+Simplified+Alternative+To+Linux+Man+Pages&url=https%3A%2F%2Ffossbytes.com%2Ftldr-pages-linux-man-pages-alternative%2F&via=%40fossbytes14 +[10]:http://plus.google.com/share?url=https://fossbytes.com/tldr-pages-linux-man-pages-alternative/ +[11]:http://pinterest.com/pin/create/button/?url=https://fossbytes.com/tldr-pages-linux-man-pages-alternative/&media=https://fossbytes.com/wp-content/uploads/2017/11/tldr-page-ubuntu.jpg +[12]:https://fossbytes.com/linux-lexicon-man-pages-navigation/ +[13]:https://github.com/tldr-pages/tldr +[14]:https://fossbytes.com/wp-content/uploads/2017/11/tar-man-page.jpg +[15]:https://fossbytes.com/wp-content/uploads/2017/11/tar-tldr-page.jpg +[16]:https://fossbytes.com/wp-content/uploads/2017/11/tldr-page-of-apt.jpg +[17]:https://fossbytes.com/wp-content/uploads/2017/11/tldr-kill-command.jpg +[18]:https://tldr.ostera.io/ +[19]:https://itunes.apple.com/us/app/tldt-pages/id1071725095?ls=1&mt=8 +[20]:https://play.google.com/store/apps/details?id=io.github.hidroh.tldroid +[21]:https://fossbytes.com/wp-content/uploads/2017/11/tldr-app-ios.jpg +[22]:https://fossbytes.com/wp-content/uploads/2017/11/tldr-page-ubuntu.jpg +[23]:https://fossbytes.com/a-z-list-linux-command-line-reference/ diff --git a/published/201812/20171223 Celebrate Christmas In Linux Way With These Wallpapers.md b/published/201812/20171223 Celebrate Christmas In Linux Way With These Wallpapers.md new file mode 100644 index 0000000000..3aa2e6f3ea --- /dev/null +++ b/published/201812/20171223 Celebrate Christmas In Linux Way With These Wallpapers.md @@ -0,0 +1,224 @@ +[#]: collector: (lujun9972) +[#]: translator: (jlztan) +[#]: reviewer: (wxy) +[#]: publisher: (wxy) +[#]: subject: (Celebrate Christmas In Linux Way With These Wallpapers) +[#]: via: (https://itsfoss.com/christmas-linux-wallpaper/) +[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/) +[#]: url: (https://linux.cn/article-10381-1.html) + +以 Linux 的方式庆祝圣诞节 +====== + +当前正是假日季，很多人可能已经在庆祝圣诞节了。祝你圣诞快乐，新年快乐。 + +为了延续节日氛围，我将向你展示一些非常棒的圣诞主题的 [Linux 壁纸][1]。在呈现这些壁纸之前，先来看一棵 Linux 终端下的圣诞树。 + +### 让你的桌面飘雪（针对 GNOME 用户） + +- [Let it Snow on Your Linux Desktop](https://youtu.be/1QI1ludzZuA) + +如果您在 Ubuntu 18.04 或任何其他 Linux 发行版中使用 GNOME 桌面，您可以使用一个小的 [GNOME 扩展][55]并在桌面上飘雪。 + +您可以从软件中心或 GNOME 扩展网站获取此 gsnow 扩展。我建议您阅读一些关于[使用 GNOME 扩展][55]的内容。 + +安装此扩展程序后，您会在顶部面板上看到一个小雪花图标。 如果您单击一次，您会看到桌面屏幕上的小絮状物掉落。 + +![](https://itsfoss.com/wp-content/uploads/2018/12/snowfall-on-linux-desktop-1.webm) + +你可以再次点击该图标来禁止雪花落下。 + +### 在 Linux 终端下显示圣诞树 + +![Display Christmas Tree in Linux Terminal](https://i.giphy.com/xUNda6KphvbpYxL3tm.gif) + +如果你想要在终端里显示一个动画的圣诞树，你可以使用如下命令： + +``` +curl https://raw.githubusercontent.com/sergiolepore/ChristBASHTree/master/tree-EN.sh | bash +``` + +要是不想一直从互联网上获取这棵圣诞树，也可以从它的 [GitHub 仓库][2] 中获取对应的 shell 脚本，更改权限之后按照运行普通 shell 脚本的方式运行它。 + +### 使用 Perl 在 Linux 终端下显示圣诞树 + +[![Christmas Tree in Linux terminal by NixCraft][3]][4] + +这个技巧最初由 [NixCraft][5] 分享，你需要为此安装 Perl 模块。 + +说实话，我不喜欢使用 Perl 模块，因为卸载它们真的很痛苦。所以使用这个 Perl 模块时需谨记，你必须手动移除它。 + +``` +perl -MCPAN -e 'install Acme::POE::Tree' +``` + +你可以阅读 [原文][5] 来了解更多信息。 + +### 下载 Linux 圣诞主题壁纸 + +所有这些 Linux 圣诞主题壁纸都是由 Mark Riedesel 制作的，你可以在 [他的网站][6] 上找到很多其他艺术品。 + +自 2002 年以来，他几乎每年都在制作这样的壁纸。可以理解的是，最早的一些壁纸不具有现代的宽高比。我把它们按时间倒序排列。 + +注意一个小地方，这里显示的图片都是高度压缩的，因此你要通过图片下方提供的链接进行下载。 + +![Christmas Linux Wallpaper][56] + +*[下载此壁纸][57]* + +![Christmas Linux Wallpaper][7] + +*[下载此壁纸][8]* + +[![Christmas Linux Wallpapers][9]][10] + +*[下载此壁纸][11]* + +[![Christmas Linux Wallpapers][12]][13] + +*[下载此壁纸][14]* + +[![Christmas Linux Wallpapers][15]][16] + +*[下载此壁纸][17]* + +[![Christmas Linux Wallpapers][18]][19] + +*[下载此壁纸][20]* + +[![Christmas Linux Wallpapers][21]][22] + +*[下载此壁纸][23]* + +[![Christmas Linux Wallpapers][24]][25] + +*[下载此壁纸][26]* + +[![Christmas Linux Wallpapers][27]][28] + +*[下载此壁纸][29]* + +[![Christmas Linux Wallpapers][30]][31] + +*[下载此壁纸][32]* + +[![Christmas Linux Wallpapers][33]][34] + +*[下载此壁纸][35]* + +[![Christmas Linux Wallpapers][36]][37] + +*[下载此壁纸][38]* + +[![Christmas Linux Wallpapers][39]][40] + +*[下载此壁纸][41]* + +[![Christmas Linux Wallpapers][42]][43] + +*[下载此壁纸][44]* + +[![Christmas Linux Wallpapers][45]][46] + +*[下载此壁纸][47]* + +[![Christmas Linux Wallpapers][48]][49] + +*[下载此壁纸][50]* + +### 福利：Linux 圣诞颂歌 + +这是给你的一份福利，给像我们一样的 Linux 爱好者的关于 Linux 的圣诞颂歌。 + +在 [《计算机世界》的一篇文章][51] 中，[Sandra Henry-Stocker][52] 分享了这些圣诞颂歌。摘录片段如下： + +这一段用的 [Chestnuts Roasting on an Open Fire][53] 的曲调： + +> Running merrily on open source +> +> With users happy as can be +> +> We’re using Linux and getting lots done + +> And happy everything is free + +这一段用的 [The Twelve Days of Christmas][54] 的曲调： + +> On my first day with Linux, my admin gave to me a password and a login ID +> +> On my second day with Linux my admin gave to me two new commands and a password and a login ID + +在 [这里][51] 阅读完整的颂歌。 + +Linux 快乐！ + +------ + +via: https://itsfoss.com/christmas-linux-wallpaper/ + +作者：[Abhishek Prakash][a] +选题：[lujun9972][b] +译者：[jlztan](https://github.com/jlztan) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/abhishek/ +[b]: https://github.com/lujun9972 +[1]: https://itsfoss.com/beautiful-linux-wallpapers/ +[2]: https://github.com/sergiolepore/ChristBASHTree +[3]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2016/12/perl-tree.gif?resize=600%2C622&ssl=1 +[4]: https://itsfoss.com/christmas-linux-wallpaper/perl-tree/ +[5]: https://www.cyberciti.biz/open-source/command-line-hacks/linux-unix-desktop-fun-christmas-tree-for-your-terminal/ +[6]: http://www.klowner.com/ +[7]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/christmas-linux-wallpaper-featured.jpeg?resize=800%2C450&ssl=1 +[8]: http://klowner.com/wallery/christmas_tux_2017/download/ChristmasTux2017_3840x2160.png +[9]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2016_3840x2160_result.jpg?resize=800%2C450&ssl=1 +[10]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2016_3840x2160_result/ +[11]: http://www.klowner.com/wallpaper/christmas_tux_2016/ +[12]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2015_2560x1920_result.jpg?resize=800%2C600&ssl=1 +[13]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2015_2560x1920_result/ +[14]: http://www.klowner.com/wallpaper/christmas_tux_2015/ +[15]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2014_2560x1440_result.jpg?resize=800%2C450&ssl=1 +[16]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2014_2560x1440_result/ +[17]: http://www.klowner.com/wallpaper/christmas_tux_2014/ +[18]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/christmastux2013_result.jpg?resize=800%2C450&ssl=1 +[19]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2013_result/ +[20]: http://www.klowner.com/wallpaper/christmas_tux_2013/ +[21]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2012_2560x1440_result.jpg?resize=800%2C450&ssl=1 +[22]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2012_2560x1440_result/ +[23]: http://www.klowner.com/wallpaper/christmas_tux_2012/ +[24]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/christmastux2011_2560x1440_result.jpg?resize=800%2C450&ssl=1 +[25]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2011_2560x1440_result/ +[26]: http://www.klowner.com/wallpaper/christmas_tux_2011/ +[27]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2016/12/christmastux2010_5120x2880_result.jpg?resize=800%2C450&ssl=1 +[28]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2010_5120x2880_result/ +[29]: http://www.klowner.com/wallpaper/christmas_tux_2010/ +[30]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2009_1600x1200_result.jpg?resize=800%2C600&ssl=1 +[31]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2009_1600x1200_result/ +[32]: http://www.klowner.com/wallpaper/christmas_tux_2009/ +[33]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2008_2560x1600_result.jpg?resize=800%2C500&ssl=1 +[34]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2008_2560x1600_result/ +[35]: http://www.klowner.com/wallpaper/christmas_tux_2008/ +[36]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2007_2560x1600_result.jpg?resize=800%2C500&ssl=1 +[37]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2007_2560x1600_result/ +[38]: http://www.klowner.com/wallpaper/christmas_tux_2007/ +[39]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2006_1024x768_result.jpg?resize=800%2C600&ssl=1 +[40]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2006_1024x768_result/ +[41]: http://www.klowner.com/wallpaper/christmas_tux_2006/ +[42]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2005_1600x1200_result.jpg?resize=800%2C600&ssl=1 +[43]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2005_1600x1200_result/ +[44]: http://www.klowner.com/wallpaper/christmas_tux_2005/ +[45]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2004_1600x1200_result.jpg?resize=800%2C600&ssl=1 +[46]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2004_1600x1200_result/ +[47]: http://www.klowner.com/wallpaper/christmas_tux_2004/ +[48]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2002_1600x1200_result.jpg?resize=800%2C600&ssl=1 +[49]: https://itsfoss.com/christmas-linux-wallpaper/christmastux2002_1600x1200_result/ +[50]: http://www.klowner.com/wallpaper/christmas_tux_2002/ +[51]: http://www.computerworld.com/article/3151076/linux/merry-linux-to-you.html +[52]: https://twitter.com/bugfarm +[53]: https://www.youtube.com/watch?v=dhzxQCTCI3E +[54]: https://www.youtube.com/watch?v=oyEyMjdD2uk +[55]: https://itsfoss.com/gnome-shell-extensions/ +[56]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2016/12/ChristmasTux2018.jpeg?w=800&ssl=1 +[57]: http://www.klowner.com/wallery/christmas_tux_2018/download/ChristmasTux2018_4K_3840x2160.png diff --git a/published/201812/20171223 My personal Email setup - Notmuch, mbsync, postfix and dovecot.md b/published/201812/20171223 My personal Email setup - Notmuch, mbsync, postfix and dovecot.md new file mode 100644 index 0000000000..12f45713d4 --- /dev/null +++ b/published/201812/20171223 My personal Email setup - Notmuch, mbsync, postfix and dovecot.md @@ -0,0 +1,240 @@ +我的个人电子邮件系统设置：notmuch、mbsync、Postfix 和 dovecot +====== + +我使用个人电子邮件系统已经相当长的时间了，但是一直没有记录过文档。最近我换了我的笔记本电脑（职业变更导致的变动），我在试图重新创建本地邮件系统时迷茫了。所以这篇文章是一个给自己看的文档，这样我就不用费劲就能再次搭建出来。 + +### 服务器端 + +我运行自己的邮件服务器，并使用 Postfix 作为 SMTP 服务器，用 Dovecot 实现 IMAP。我不打算详细介绍如何配置这些设置，因为我的设置主要是通过使用 Jonas 为 Redpill 基础架构创建的脚本完成的。什么是 Redpill？（用 Jonas 自己的话说）： + +> \ Redpill 是一个概念：一种设置 Debian hosts 去跨组织协作的方式 +> +> \ 我发展了这个概念，并将其首次用于 Redpill 网中网：redpill.dk，其中涉及到了我自己的网络（jones.dk），我的主要客户的网络（homebase.dk），一个包括 Skolelinux Germany（free-owl.de）的在德国的网络，和 Vasudev 的网络（copyninja.info） + +除此之外， 我还有一个 dovecot sieve 过滤，根据邮件的来源，对邮件进行高级分类，将其放到各种文件夹中。所有的规则都存在于每个有邮件地址的账户下的 `~/dovecot.sieve` 文件中。 + +再次，我不会详细介绍如何设置这些东西，因为这不是我这个帖子的目标。 + +### 在我的笔记本电脑上 + +在我的笔记本电脑上，我已经按照 4 个部分设置 + + 1. 邮件同步：使用 `mbsync` 命令完成 + 2. 分类：使用 notmuch 完成 + 3. 阅读：使用 notmuch-emacs 完成 + 4. 邮件发送：使用作为中继服务器和 SMTP 客户端运行的 Postfix 完成。 + +### 邮件同步 + +邮件同步是使用 `mbsync` 工具完成的， 我以前是 OfflineIMAP 的用户，最近切换到 `mbsync`，因为我觉得它比 OfflineIMAP 的配置更轻量、更简单。该命令是由 isync 包提供的。 + +配置文件是 `~/.mbsyncrc`。下面是我的例子与一些个人设置。 + +``` +IMAPAccount copyninja +Host imap.copyninja.info +User vasudev +PassCmd "gpg -q --for-your-eyes-only --no-tty --exit-on-status-write-error --batch --passphrase-file ~/path/to/passphrase.txt -d ~/path/to/mailpass.gpg" +SSLType IMAPS +SSLVersion TLSv1.2 +CertificateFile /etc/ssl/certs/ca-certificates.crt + + +IMAPAccount gmail-kamathvasudev +Host imap.gmail.com +User kamathvasudev@gmail.com +PassCmd "gpg -q --for-your-eyes-only --no-tty --exit-on-status-write-error --batch --passphrase-file ~/path/to/passphrase.txt -d ~/path/to/mailpass.gpg" +SSLType IMAPS +SSLVersion TLSv1.2 +CertificateFile /etc/ssl/certs/ca-certificates.crt + +IMAPStore copyninja-remote +Account copyninja + +IMAPStore gmail-kamathvasudev-remote +Account gmail-kamathvasudev + +MaildirStore copyninja-local +Path ~/Mail/vasudev-copyninja.info/ +Inbox ~/Mail/vasudev-copyninja.info/INBOX + +MaildirStore gmail-kamathvasudev-local +Path ~/Mail/Gmail-1/ +Inbox ~/Mail/Gmail-1/INBOX + +Channel copyninja +Master :copyninja-remote: +Slave :copyninja-local: +Patterns * +Create Both +SyncState * +Sync All + +Channel gmail-kamathvasudev +Master :gmail-kamathvasudev-remote: +Slave :gmail-kamathvasudev-local: +# Exclude everything under the internal [Gmail] folder, except the interesting folders +Patterns * ![Gmail]* +Create Both +SyncState * +Sync All +``` + +对上述配置中的一些有趣部分进行一下说明。一个是 PassCmd，它允许你提供 shell 命令来获取帐户的密码。这样可以避免在配置文件中填写密码。我使用 gpg 的对称加密，并在我的磁盘上存储密码。这当然是由 Unix ACL 保护安全的。 + +实际上，我想使用我的公钥来加密文件，但当脚本在后台或通过 systemd 运行时，解锁文件看起来很困难 （或者说几乎不可能）。如果你有更好的建议，我洗耳恭听:-)。 + +下一个指令部分是 Patterns。这使你可以有选择地同步来自邮件服务器的邮件。这对我来说真的很有帮助，可以排除所有的 “[Gmail]/ folders” 垃圾目录。 + +### 邮件分类 + +一旦邮件到达你的本地设备，我们需要一种方法来轻松地在邮件读取器中读取邮件。我最初的设置使用本地 dovecot 实例提供同步的 Maildir，并在 Gnus 中阅读。这种设置相比于设置所有的服务器软件是有点大题小作，但 Gnus 无法很好地应付 Maildir 格式，这是最好的方法。这个设置也有一个缺点，那就是在你快速搜索邮件时，要搜索大量邮件。而这就是 notmuch 的用武之地。 + +notmuch 允许我轻松索引上千兆字节的邮件档案而找到我需要的东西。我已经创建了一个小脚本，它结合了执行 `mbsync` 和 `notmuch`。我使用 dovecot sieve 来基于实际上创建在服务器端的 Maildirs 标记邮件。下面是我的完整 shell 脚本，它执行同步分类和删除垃圾邮件的任务。 + +``` +#!/bin/sh + +MBSYNC=$(pgrep mbsync) +NOTMUCH=$(pgrep notmuch) + +if [ -n "$MBSYNC" -o -n "$NOTMUCH" ]; then + echo "Already running one instance of mail-sync. Exiting..." + exit 0 +fi + +echo "Deleting messages tagged as *deleted*" +notmuch search --format=text0 --output=files tag:deleted |xargs -0 --no-run-if-empty rm -v + +echo "Moving spam to Spam folder" +notmuch search --format=text0 --output=files tag:Spam and \ + to:vasudev@copyninja.info | \ + xargs -0 -I {} --no-run-if-empty mv -v {} ~/Mail/vasudev-copyninja.info/Spam/cur +notmuch search --format=text0 --output=files tag:Spam and + to:vasudev-debian@copyninja.info | \ + xargs -0 -I {} --no-run-if-empty mv -v {} ~/Mail/vasudev-copyninja.info/Spam/cur + + +MDIR="vasudev-copyninja.info vasudev-debian Gmail-1" +mbsync -Va +notmuch new + +for mdir in $MDIR; do + echo "Processing $mdir" + for fdir in $(ls -d /home/vasudev/Mail/$mdir/*); do + if [ $(basename $fdir) != "INBOX" ]; then + echo "Tagging for $(basename $fdir)" + notmuch tag +$(basename $fdir) -inbox -- folder:$mdir/$(basename $fdir) + fi + done +done +``` + +因此，在运行 `mbsync` 之前，我搜索所有标记为“deleted”的邮件，并将其从系统中删除。接下来，我在我的帐户上查找标记为“Spam”的邮件，并将其移动到“Spam”文件夹。你没看错，这些邮件逃脱了垃圾邮件过滤器进入到我的收件箱，并被我亲自标记为垃圾邮件。 + +运行 `mbsync` 后，我基于它们的文件夹标记邮件（搜索字符串 `folder:`）。这让我可以很容易地得到一个邮件列表的内容，而不需要记住列表地址。 + +### 阅读邮件 + +现在，我们已经实现同步和分类邮件，是时候来设置阅读部分。我使用 notmuch-emacs 界面来阅读邮件。我使用 emacs 的 Spacemacs 风格，所以我花了一些时间写了一个私有层，它将我所有的快捷键和分类集中在一个地方，而不会扰乱我的整个 `.spacemacs` 文件。你可以在 [notmuch-emacs-layer 仓库][1] 找到我的私有层的代码。 + +### 发送邮件 + +能阅读邮件这还不够，我们也需要能够回复邮件。而这是最近是我感到迷茫的一个略显棘手的部分，以至于不得不写这篇文章，这样我就不会再忘记了。（当然也不必在网络上参考一些过时的帖子。） + +我的系统发送邮件使用 Postfix 作为 SMTP 客户端，使用我自己的 SMTP 服务器作为它的中继主机。中继的问题是，它不能是具有动态 IP 的主机。有两种方法可以允许具有动态 IP 的主机使用中继服务器， 一种是将邮件来源的 IP 地址放入 `my_network` 或第二个使用 SASL 身份验证。 + +我的首选方法是使用 SASL 身份验证。为此，我首先要为每台机器创建一个单独的账户，它将把邮件中继到我的主服务器上。想法是不使用我的主帐户 SASL 进行身份验证。（最初我使用的是主账户，但 Jonas 给出了可行的按账户的想法） + +``` +adduser _relay +``` + +这里替换 `` 为你的笔记本电脑的名称或任何你正在使用的设备。现在我们需要调整 Postfix 作为中继服务器。因此，在 Postfix 配置中添加以下行： + +``` +# SASL authentication +smtp_sasl_auth_enable = yes +smtp_tls_security_level = encrypt +smtp_sasl_tls_security_options = noanonymous +relayhost = [smtp.copyninja.info]:submission +smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd +``` + +因此， 这里的 `relayhost` 是用于将邮件转发到互联网的 Postfix 实例的服务器名称。`submission` 的部分 Postfix 将邮件转发到端口 587（安全端口）。`smtp_sasl_tls_security_options` 设置为不允许匿名连接。这是必须的，以便中继服务器信任你的移动主机，并同意为你转发邮件。 + +`/etc/postfix/sasl_passwd` 是你需要存储用于服务器 SASL 身份验证的帐户密码的文件。将以下内容放入其中。 + +``` +[smtp.example.com]:submission user:password +``` + +用你已放入 `relayhost` 配置的 SMTP 服务器名称替换 `smtp.example.com`。用你创建的 `_relay` 用户及其密码替换 `user` 和 `passwd`。 + +若要保护 `sasl_passwd` 文件，并为 Postfix 创建它的哈希文件，使用以下命令。 + +``` +chown root:root /etc/postfix/sasl_passwd +chmod 0600 /etc/postfix/sasl_passwd +postmap /etc/postfix/sasl_passwd +``` + +最后一条命令将创建 `/etc/postfix/sasl_passwd.db` 文件，它是你的文件的 `/etc/postfix/sasl_passwd` 的哈希文件，具有相同的所有者和权限。现在重新加载 Postfix，并使用 `mail` 命令检查邮件是否从你的系统中发出。 + +### Bonus 的部分 + +好吧，因为我有一个脚本创建以上结合了邮件的同步和分类。我继续创建了一个 systemd 计时器，以定期同步后台的邮件。就我而言，每 10 分钟一次。下面是 `mailsync.timer` 文件。 + +``` +[Unit] +Description=Check Mail Every 10 minutes +RefuseManualStart=no +RefuseManualStop=no + +[Timer] +Persistent=false +OnBootSec=5min +OnUnitActiveSec=10min +Unit=mailsync.service + +[Install] +WantedBy=default.target +``` + +下面是 mailsync.service 服务，这是 mailsync.timer 执行我们的脚本所需要的。 + +``` +[Unit] +Description=Check Mail +RefuseManualStart=no +RefuseManualStop=yes + +[Service] +Type=oneshot +ExecStart=/usr/local/bin/mail-sync +StandardOutput=syslog +StandardError=syslog +``` + +将这些文件置于 `/etc/systemd/user` 目录下并运行以下代码去开启它们： + +``` +systemctl enable --user mailsync.timer +systemctl enable --user mailsync.service +systemctl start --user mailsync.timer +``` + +这就是我从系统同步和发送邮件的方式。我从 Jonas Smedegaard 那里了解到了 afew，他审阅了这篇帖子。因此， 下一步， 我将尝试使用 afew 改进我的 notmuch 配置，当然还会有一个后续的帖子:-)。 + +-------------------------------------------------------------------------------- + +via: https://copyninja.info/blog/email_setup.html + +作者：[copyninja][a] +译者：[lixinyuxx](https://github.com/lixinyuxx) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://copyninja.info +[1]:https://source.copyninja.info/notmuch-emacs-layer.git/ diff --git a/published/201812/20180101 27 open solutions to everything in education.md b/published/201812/20180101 27 open solutions to everything in education.md new file mode 100644 index 0000000000..48a4f3fa3c --- /dev/null +++ b/published/201812/20180101 27 open solutions to everything in education.md @@ -0,0 +1,91 @@ +27 个全方位的开放式教育解决方案 +====== + +> 阅读这些 2017 年 Opensource.com 发布的开放如何改进教育和学习的好文章。 + +![27 open solutions to everything in education](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/EDU_OpenEducationResources_520x292_cm.png?itok=9y4FGgRo) + +开放式理念 (从开源软件到开放硬件，再到开放原则) 正在改变教育的范式。因此，为了庆祝今年发生的一切，我收集了 2017 年（译注：本文原发布于 2018 年初）在 Opensource.com 上发表的 27 篇关于这个主题的最好的文章。我把它们分成明确的主题，而不是按人气来分类。而且，如果这 27 个故事不能满足你对教育方面开源信息的胃口，那就看看我们的合作文章吧 “[教育如何借助 Linux 和树莓派][30]”。 + +### 开放对每个人都有好处 + +1. [书评：《OPEN》探讨了开放性的广泛文化含义][1]：Scott Nesbitt 评价 David Price 的书 《OPEN》 ，该书探讨了 “开放” 不仅仅是技术转变的观点，而是 “我们未来将如何工作、生活和学习”。 +2. [通过开源技能快速开始您的职业生涯][2]: VM (Vicky) Brasseur 指出了如何借助学习开源在工作群体中脱颖而出。这个建议不仅仅是针对程序员的；设计师、作家、营销人员和其他创意专业人士也对开源的成功至关重要。 +3. [研究生学位可以让你跳槽到开源职位][3]：引用的研究表明会 Linux 技能会带来更高的薪水， Joshua Pearce 说对开源的熟练和研究生学位是无与伦比的职业技能组合。 +4. [彻底改变了宾夕法尼亚的学校文化的三种实践][4]：Charlie Reisinger 向我们展示了开放式实践是如何在宾夕法尼亚州的一个学区创造一种更具包容性、敏捷性和开放性的文化的。Charlie 说，这不仅仅是为了省钱；该区还受益于 “开放式领导原则，促进师生创新，帮助更好地吸引社区，创造一个更有活力和包容性的学习社区”。 +5. [使用开源工具促使学生进步的 15 种方法][5]：我写了开源是如何让学生自由探索、补拙和学习的，不管他们是在学习基本的数字化素养，还是通过有趣的项目来扩展这些技能。 +6. [开发人员有机会编写好的代码][6]：开源往往是对社会有益的项目的支柱。正如 Benetech Labs 副总裁 Ahn Bui 在这次采访中指出的那样：“建立开放数据标准是打破数据孤岛不可或缺的一步。这些开放标准将为互操作性提供基础，进而转化为更多的组织共同建设，往往更具成本效益。最终目标是以同样的成本甚至更低的成本为更多的人服务。” + +### 用于再融合和再利用的开放式教育资源 + +1. [学术教员可以和维基百科一起教学吗？][7]：Wiki Ed 的项目总监 LiAnna Davis 讨论开放式教育资源open educational resources (OER) ，如 Wiki Ed，是如何提供高质量且经济实惠的开源学习资源作为课堂教学工具。 +2. [书本内外？开放教育资源的状态][8]：Cable Green 是 Creative Common 开放教育主管，分享了高等教育中教育面貌是如何变化的，以及 Creative Common 正在采取哪些措施来促进教育。 +3. [急需符合标准的课程的学校系统找到了希望][9]：Karen Vaites 是 Open Up Resources 社区布道师和首席营销官，谈论了非营利组织努力为 K-12 学校提供开放的、标准一致的课程。 +4. [夏威夷大学如何解决当今高等教育的问题][10]：夏威夷大学 Manoa 分校的教育技术专家 Billy Meinke 表示，在大学课程中过渡到 ORE 将 “使教师能够控制他们教授的内容，我们预计这将为他们节省学生的费用。” +5. [开放式课程如何削减高等教育成本][11]：塞勒学院的教育总监 Devon Ritter 报告了塞勒学院是如何建立以公开许可内容为基础的大学学分课程，目的是使更多的人能够负担得起和获得高等教育。 +6. [开放教育资源运动在提速][12]：Alexis Clifton 是纽约州立大学的 OER 服务的执行董事，描述了纽约 800 万美元的投资如何刺激开放教育的增长，并使大学更实惠。 +7. [开放项目合作，从小学到大学教室][13]：来自杜克大学的 Aria F. Chernik 探索 OSPRI (开源教育学的研究与创新)， 这是杜克大学和红帽的合作，旨在建立一个 21 世纪的，开放设计的 preK-12 学习生态系统。 +8. [Perma.cc 将阻止学术链接腐烂][14]：：弗吉尼亚理工大学的 Phillip Young 写的关于 Perma.cc 的文章，这种一种“链接腐烂”的解决方案，在学术论文中的超链接随着时间的推移而消失或变化的概览很高。 +9. [开放教育：学生如何通过创建开放教科书来节省资金][15]：OER 先驱 Robin DeRosa 谈到 “引入公开许可教科书的自由，以及教育和学习应结合包容性生态系统，以增强公益的总体理念”。 + +### 课堂上的开源工具 + +1. [开源棋盘游戏如何拯救地球][16]：Joshua Pearce 写的关于拯救地球的一个棋盘游戏，这是一款让学生在玩乐和为创客社区做出贡献的同时解决环境问题的棋盘游戏。 +2. [一个教孩子们如何阅读的新 Android 应用程序][17]：Michael Hall 谈到了他在儿子被诊断为自闭症后为他开发的儿童识字应用 Phoenicia，以及良好编码的价值，和为什么用户测试比你想象的更重要。 +3. [8 个用于教育的开源 Android 应用程序][18]：Joshua Allen Holm 推荐了 8 个来自 F-Droid 软件库的开源应用，使我们可以将智能手机用作学习工具。 +4. [MATLA B的 3 种开源替代方案][19]：Jason Baker 更新了他 2016 年的开源数学计算软件调查报告，提供了 MATLAB 的替代方案，这是数学、物理科学、工程和经济学中几乎无处不在的昂贵的专用解决方案。 +5. [SVG 与教孩子编码有什么关系？][20]：退休工程师 Jay Nick 谈论他如何使用艺术作为一种创新的方式，向学生介绍编码。他在学校做志愿者，使用 SVG 来教授一种结合数学和艺术原理的编码方法。 +6. [5 个破灭的神话：在高等教育中使用开源][21]: 拥有德克萨斯理工大学美术博士学位的 Kyle Conway 分享他在一个由专有解决方案统治的世界中使用开源工具的经验。 Kyle 说有一种偏见，反对在计算机科学以外的学科中使用开源：“很多人认为非技术专业的学生不能使用 Linux，他们对在高级学位课程中使用 Linux 的人做出了很多假设……嗯，这是有可能的，我就是证明。” +7. [大学开源工具列表][22]：Aaron Cocker 概述了他在攻读计算机科学本科学位时使用的开源工具 (包括演示、备份和编程软件)。 +8. [5 个可帮助您学习优秀 KDE 应用程序][23]：Zsolt Szakács 提供五个 KDE 应用程序，可以帮助任何想要学习新技能或培养现有技能的人。 + +### 在教室编码 + +1. [如何尽早让下一代编码][24]：Bryson Payne 说我们需要在高中前教孩子们学会编码: 到了九年级，80% 的女孩和 60% 的男孩已经从 STEM 职业中自选。但他建议，这不仅仅是就业和缩小 IT 技能差距的问题。“教一个年轻人编写代码可能是你能给他们的最改变生活的技能。而且这不仅仅是一个职业提升者。编码是关于解决问题，它是关于创造力，更重要的是，它是提升能力”。 +2. [孩子们无法在没有计算机的情况下编码][25]：Patrick Masson 推出了 FLOSS 儿童桌面计划， 该计划教授服务不足学校的学生使用开源软件 (如 Linux、LibreOffice 和 GIMP) 重新利用较旧的计算机。该计划不仅为破旧或退役的硬件注入新的生命，还为学生提供了重要的技能，而且还为学生提供了可能转化为未来职业生涯的重要技能。 +3. [如今 Scratch 是否能像 80 年代的 LOGO 语言一样教孩子们编码？][26]：Anderson Silva 提出使用 [Scratch][27] 以激发孩子们对编程的兴趣，就像在 20 世纪 80 年代开始使用 LOGO 语言时一样。 +4. [通过这个拖放框架学习Android开发][28]：Eric Eslinger 介绍了 App Inventor，这是一个编程框架，用于构建 Android 应用程序使用可视块语言（类似 Scratch 或者 [Snap][29]）。 + +在这一年里，我们了解到，教育领域的各个方面都有了开放的解决方案，我预计这一主题将在 2018 年及以后继续下去。在未来的一年里，你是否希望 Opensource.com 涵盖开放式的教育主题？如果是， 请在评论中分享你的想法。 + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/1/best-open-education + +作者：[Don Watkins][a] +译者：[lixinyuxx](https://github.com/lixinyuxx) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/don-watkins +[1]:https://opensource.com/article/17/7/book-review-open +[2]:https://opensource.com/article/17/8/jump-start-your-career +[3]:https://opensource.com/article/17/1/grad-school-open-source-academic-lab +[4]:https://opensource.com/article/17/7/open-school-leadership +[5]:https://opensource.com/article/17/7/empower-students-open-source-tools +[6]:https://opensource.com/article/17/3/interview-anh-bui-benetech-labs +[7]:https://opensource.com/article/17/1/Wiki-Education-Foundation +[8]:https://opensource.com/article/17/2/future-textbooks-cable-green-creative-commons +[9]:https://opensource.com/article/17/1/open-up-resources +[10]:https://opensource.com/article/17/2/interview-education-billy-meinke +[11]:https://opensource.com/article/17/7/college-alternatives +[12]:https://opensource.com/article/17/10/open-educational-resources-alexis-clifton +[13]:https://opensource.com/article/17/3/education-should-be-open-design +[14]:https://opensource.com/article/17/9/stop-link-rot-permacc +[15]:https://opensource.com/article/17/11/creating-open-textbooks +[16]:https://opensource.com/article/17/7/save-planet-board-game +[17]:https://opensource.com/article/17/4/phoenicia-education-software +[18]:https://opensource.com/article/17/8/8-open-source-android-apps-education +[19]:https://opensource.com/alternatives/matlab +[20]:https://opensource.com/article/17/5/coding-scalable-vector-graphics-make-steam +[21]:https://opensource.com/article/17/5/how-linux-higher-education +[22]:https://opensource.com/article/17/6/open-source-tools-university-student +[23]:https://opensource.com/article/17/6/kde-education-software +[24]:https://opensource.com/article/17/8/teach-kid-code-change-life +[25]:https://opensource.com/article/17/9/floss-desktops-kids +[26]:https://opensource.com/article/17/3/logo-scratch-teach-programming-kids +[27]:https://scratch.mit.edu/ +[28]:https://opensource.com/article/17/8/app-inventor-android-app-development +[29]:http://snap.berkeley.edu/ +[30]:https://opensource.com/article/17/12/best-opensourcecom-linux-and-raspberry-pi-education diff --git a/published/201812/20180104 How Creative Commons benefits artists and big business.md b/published/201812/20180104 How Creative Commons benefits artists and big business.md new file mode 100644 index 0000000000..aefc804479 --- /dev/null +++ b/published/201812/20180104 How Creative Commons benefits artists and big business.md @@ -0,0 +1,66 @@ +你所不知道的知识共享（CC） +====== + +> 知识共享为艺术家提供访问权限和原始素材。大公司也从中受益。 + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/CreativeCommons_ideas_520x292_1112JS.png?itok=otei0vKb) + +我毕业于电影学院，毕业后在一所电影学校教书，之后进入一家主流电影工作室，我一直在从事电影相关的工作。创意产业的方方面面面临着同一个问题：创作者需要原材料。有趣的是，自由文化运动提出了解决方案，具体来说是在自由文化运动中出现的知识共享Creative Commons组织。 + +### 知识共享能够为我们提供展示片段和小样 + +和其他事情一样，创造力也需要反复练习。幸运的是，在我刚开始接触电脑时，就在一本关于渲染工场的专业杂志中接触到了开源这个存在。当时我并不理解所谓的“开源”是什么，但我知道只有开源工具能帮助我在领域内稳定发展。对我来说，知识共享也是如此。知识共享可以为艺术家们提供充满丰富艺术资源的工作室。 + +我在电影学院任教时，经常需要给学生们准备练习编辑、录音、拟音、分级、评分的示例录像。在 Jim Munroe 的独立作品 [Infest Wisely][1] 中和 [Vimeo][2] 上的知识共享内容里我总能找到我想要的。这些逼真的镜头覆盖内容十分广泛，从独立制作到昂贵的高品质的升降镜头（一般都会用无人机代替）都有。 + +![](https://opensource.com/sites/default/files/u128651/bunny.png) + +对实验主义艺术来说，确有无尽可能。知识共享提供了丰富的素材，这些材料可以用来整合、混剪等等，可以满足一位视觉先锋能够想到的任何用途。 + +在接触知识共享之前，如果我想要使用写实镜头，如果在大学，只能用之前的学生和老师拍摄的或者直接使用版权库里的镜头，或者使用有受限的版权保护的镜头。 + +### 坚守版权的底线很重要 + +知识共享同样能够创造经济效益。在某大型计算机公司的渲染工场工作时，我负责在某些硬件设施上测试渲染的运行情况，而这个测试时刻面临着被搁置的风险。做这些测试时，我用的都是[大雄兔][3]的资源，因为这个电影和它的组件都是可以免费使用和分享的。如果没有这个小短片，在接触写实资源之前我都没法完成我的实验，因为对于一个计算机公司来说，雇佣一只 3D 艺术家来按需布景是不太现实的。 + +令我震惊的是，与开源类似，知识共享已经用我们难以想象的方式支撑起了大公司。知识共享的使用可能会也可能不会影响公司的日常流程，但它填补了不足，让工作流程顺利进行。我没见到谁在他们的书中将流畅工作归功于知识共享的应用，但它确实无处不在。 + +![](https://opensource.com/sites/default/files/u128651/sintel.png) + +我也见过一些开放版权的电影，比如[辛特尔][4]，在最近的电视节目中播放了它的短片，电视的分辨率已经超过了标准媒体。 + +### 知识共享可以提供大量原材料 + +艺术家需要原材料。画家需要颜料、画笔和画布。雕塑家需要陶土和工具。数字内容编辑师需要数字内容，无论它是剪贴画还是音效或者是电子游戏里的现成的精灵。 + +数字媒介赋予了人们超能力，让一个人就能完成需要一组人员才能完成的工作。事实上，我们大部分都好高骛远。我们想做高大上的项目，想让我们的成果不论是视觉上还是听觉上都无与伦比。我们想塑造的是宏大的世界，紧张的情节，能引起共鸣的作品，但我们所拥有的时间精力和技能与之都不匹配，达不到想要的效果。 + +是知识共享再一次拯救了我们，在 [Freesound.org][5]、 [Openclipart.org][6]、 [OpenGameArt.org][7] 等等网站上都有大量的开放版权艺术材料。通过知识共享，艺术家可以使用各种他们自己没办法创造的原材料，来完成他们原本完不成的工作。 + +最神奇的是，不用自己投资，你放在网上给大家使用的原材料就能变成精美的作品，而这是你从没想过的。我在知识共享上面分享了很多音乐素材，它们现在用于无数的专辑和电子游戏里。有些人用了我的材料会通知我，有些是我自己发现的，所以这些材料的应用可能比我知道的还有多得多。有时我会偶然看到我亲手画的标志出现在我从没听说过的软件里。我见到过我为 [Opensource.com][8] 写的文章在别处发表，有的是论文的参考文献，白皮书或者参考资料中。 + +### 知识共享所代表的自由文化也是一种文化 + +“自由文化”这个说法过于累赘，文化，从概念上来说，是一个有机的整体。在这种文化中社会逐渐成长发展，从一个人到另一个。它是人与人之间的互动和思想交流。自由文化是自由缺失的现代世界里的特殊产物。 + +如果你也想对这样的局限进行反抗，想把你的思想、作品、你自己的文化分享给全世界的人，那么就来和我们一起，使用知识共享吧！ + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/1/creative-commons-real-world + +作者：[Seth Kenlon][a] +译者：[Valoniakim](https://github.com/Valoniakim) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/seth +[1]:http://infestwisely.com +[2]:https://vimeo.com/creativecommons +[3]:https://peach.blender.org/ +[4]:https://durian.blender.org/ +[5]:http://freesound.org +[6]:http://openclipart.org +[7]:http://opengameart.org +[8]:https://opensource.com/ diff --git a/published/201812/20180128 Getting Linux Jobs.md b/published/201812/20180128 Getting Linux Jobs.md new file mode 100644 index 0000000000..9bfaf0e1e5 --- /dev/null +++ b/published/201812/20180128 Getting Linux Jobs.md @@ -0,0 +1,95 @@ +Linux 求职建议 +====== + +通过对招聘网站数据的仔细研究，我们发现，即使是非常有经验的 Linux 程序员，也会在面试中陷入困境。 + +这就导致了很多优秀并且有经验的人无缘无故地找不到合适的工作，因为如今的就业市场需要我们有一些手段来提高自己的竞争力。 + +我有两个同事和一个表哥，他们都有 RedHat 认证，管理过比较大的服务器机房，也都收到过前雇主的认真推荐。 + +可是，在他们应聘的时候，所有的这些证书、本身的能力、工作经验好像都没有起到任何作用，他们所面对的招聘广告是某人从技术词汇中临时挑选的一些“技能片段”所组成的。 + +现如今，礼貌变得过时了，**不回应**变成了发布招聘广告的公司的新沟通方式。 + +这同样也意味着大多公司的招聘或者人事可能会**错过**非常优秀的应聘者。 + +我之所以敢说的如此肯定，是因为现在招聘广告大多数看上去都非常的滑稽。 + +[Reallylinux.com][3] 另一位特约撰稿人 Walter ，发表过一篇关于 [招聘广告疯掉了][4] 的文章。 + +他说的也许是对的，可是我认为 Linux 工作应聘者可以通过注意招聘广告的**三个关键点**避免落入陷阱。 + +**首先**，很少会有 Linux 系统管理员的招聘广告只针对 Linux 有要求。 + +一定要注意很少有 Linux 系统管理员的职位是实际在服务器上跑 Linux的，反而，很多在搜索 “Linux 管理员” 得到的职位实际上是指大量的 *NX 操作系统的。 + +举个例子，有一则关于 **Linux 管理员** 的招聘广告： + +> 该职位需要为建立系统集成提供支持，尤其是 BSD 应用的系统安装... + +或者有一些其他的要求： + +> 有 Windows 系统管理经验的。 + +最为讽刺的是，如果你在应聘面试的时候表现出专注于 Linux 的话，你可能不会被聘用。 + +另外，如果你直接把 Linux 写在你的特长或者专业上，他们可能都不会仔细看你的简历，因为他们根本区分不了 UNIX、BSD、Linux。 + +最终的结果就是，如果你太老实，只在简历上写了 Linux，你可能会被直接过掉，但是如果你把 Linux 改成 UNIX/Linux 的话，可能会走得更远。 + +我有两个同事最后修改了他们的简历，然后获得了更好的面试机会，虽然依旧没有被聘用，因为大多数招聘广告其实已经内定人员了，这些招聘信息被放出来仅仅是为了表现出他们有招聘的想法。 + +**第二点**，公司里唯一在乎系统管理员职位的只有技术主管，其他人包括人事或管理层根本不关心这个。 + +我记得有一次开会旁听的时候，听见一个执行副总裁把服务器管理人员说成“一毛钱一打的人”，这种想法是多么的奇怪啊。 + +讽刺的是，等到邮件系统出故障，电话交换机连接时不时会断开，或者核心商业文件从企业内网中消失的时候，这些总裁又是最先打电话给系统管理员的。 + +或许如果他们不整天在电话留言中说那么多空话，或者不往邮件里塞满妻子的照片和旅行途中的照片的话，服务器可能就不会崩溃。 + +请注意，招聘 Linux 运维或者服务器管理员的广告被放出来是因为公司**技术层**认为有迫切的需求。你也不需要和人事或者公司高层聊什么，搞清楚谁是招聘的技术经理然后打电话给他们。 + +你需要直接联系他们因为“有些技术问题”是人事回答不了的，即使你只有 60 秒的时间可以和他们交流，你也必须抓住这个机会和真正有需求并且懂技术的人沟通。 + +那如果人事的漂亮 MM 不让你直接联系技术怎么办呢？ + +开始记得问人事一些技术性问题，比如说他们的 Linux 集群是如何建立的，它们运行在独立的虚拟机上吗？这些技术性的问题会让人事变得不耐烦，最后让你有机会问出“我能不能直接联系你们团队的技术人员”。 + +如果对方的回答是“应该可以”或者“稍后回复你”，那么他们可能已经在两周前就已经计划好了找一个人来填补这个空缺，比如说人事部员工的未婚夫。**他们只是不希望看起来太像裙带主义，而是带有一点利己主义的不确定主义。** + +所以一定要记得花点时间弄清楚到底谁是发布招聘广告的直接**技术**负责人，然后和他们聊一聊，这可能会让你少一番胡扯并且让你更有可能应聘成功。 + +**第三点**，现在的招聘广告很少有完全真实的内容了。 + +我以前见过一个招聘具有高级别专家也不会有的专门知识的初级系统管理员的广告，他们的计划是列出公司的发展计划蓝图，然后找到应聘者。 + +在这种情况下，你应聘 Linux 管理员职位应该提供几个关键性信息，例如工作经验和相关证书。 + +诀窍在于，用这些关键词尽量装点你的简历，以匹配他们的招聘信息，这样他们几乎不可能发现你缺失了哪个关键词。 + +这并不一定会让你成功找到一份工作，但它可以让你获得一次面试机会，这也算是一个巨大的进步。 + +通过理解和应用以上三点，或许可以让那些寻求 Linux 管理员工作的人能够比那些只有一线地狱机会的人领先一步。 + +即使这些建议不能让你马上得到面试机会，你也可以利用这些经验和意识去参加贸易展或公司主办的技术会议等活动。 + +我强烈建议你们也经常参加这种活动，尤其是当它们比较近的话，可以给你一个扩展人脉的机会。 + +请记住，如今的职业人脉已经失去了原来的意义了，现在只是可以用来获取“哪些公司实际上在招聘、哪些公司只是为了给股东带来增长的表象而在职位方面撒谎”的小道消息。 + + +-------------------------------------------------------------------------------- + +via: http://reallylinux.com/docs/gettinglinuxjobs.shtml + +作者：[Andrea W.Codingly][a] +译者：[Ryze-Borgia](https://github.com/Ryze-Borgia) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:http://reallylinux.com +[1]:http://www.reallylinux.com +[2]:http://reallylinux.com/docs/linuxrecessionproof.shtml +[3]:http://reallylinux.com +[4]:http://reallylinux.com/docs/wantadsmad.shtml diff --git a/published/201812/20180130 Graphics and music tools for game development.md b/published/201812/20180130 Graphics and music tools for game development.md new file mode 100644 index 0000000000..7e77e30d67 --- /dev/null +++ b/published/201812/20180130 Graphics and music tools for game development.md @@ -0,0 +1,179 @@ +用于游戏开发的图形和音乐工具 +====== +> 要在三天内打造一个可玩的游戏，你需要一些快速而稳定的好工具。 + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/OSDC_Life_opengame.png?itok=JPxruL3k) + +在十月初，我们的俱乐部马歇尔大学的 [Geeks and Gadgets][1] 参加了首次 [Open Jam][2]，这是一个庆祝最佳开源工具的游戏 Jam。游戏 Jam 是一种活动，参与者以团队协作的方式来开发有趣的计算机游戏。Jam 一般都很短，仅有三天，并且非常累。Opensource.com 在八月下旬[发布了][3] Open Jam 活动，足有 [45 支游戏][4] 进入到了竞赛中。 + +我们的俱乐部希望在我们的项目中创建和使用开放源码软件，所以 Open Jam 自然是我们想要参与的 Jam 了。我们提交的游戏是一个实验性的游戏，名为 [Mark My Words][5]。我们使用了多种自由和开放源码 (FOSS) 工具来开发它；在这篇文章中，我们将讨论一些我们使用的工具和我们注意到可能有潜在阻碍的地方。 + +### 音频工具 + +#### MilkyTracker + +[MilkyTracker][6] 是一个可用于编曲老式视频游戏中的音乐的软件包。它是一种[音乐声道器][7]music tracker，是一个强大的 MOD 和 XM 文件创建器，带有基于特征网格的模式编辑器。在我们的游戏中，我们使用它来编曲大多数的音乐片段。这个程序最好的地方是，它比我们其它的大多数工具消耗更少的硬盘空间和内存。虽然如此，MilkyTracker 仍然非常强大。 + +![](https://opensource.com/sites/default/files/u128651/mtracker.png) + +其用户界面需要一会来习惯，这里有对一些想试用 MilkyTracker 的音乐家的一些提示： + + * 转到 “Config > Misc.” ，设置编辑模式的控制风格为 “MilkyTracker”，这将给你提供几乎全部现代键盘快捷方式。 + * 用 `Ctrl+Z` 撤销 + * 用 `Ctrl+Y` 重做 + * 用空格键切换模式编辑方式 + * 用退格键删除先前的音符 + * 用插入键来插入一行 + * 默认情况下，一个音符将持续作用，直到它在该频道上被替换。你可以明确地结束一个音符，通过使用一个反引号（`）键来插入一个 KeyOff 音符 + * 在你开始谱写乐曲前，你需要创建或查找采样。我们建议在诸如 [Freesound][9] 或 [ccMixter][10] 这样的网站上查找采用 [Creative Commons][8] 协议的采样， + +另外，把 [MilkyTracker 文档页面][11] 放在手边。它含有数不清的教程和手册的链接。一个好的起点是在该项目 wiki 上的 [MilkyTracker 指南][12]。 + +#### LMMS + +我们的两个音乐家使用多用途的现代音乐创建工具 [LMMS][13]。它带有一个绝妙的采样和效果库，以及多种多样的灵活的插件来生成独特的声音。LMMS 的学习曲线令人吃惊的低，在某种程度上是因为其好用的节拍/低音线编辑器。 + +![](https://opensource.com/sites/default/files/u128651/lmms_plugins.png) + +我们对于想试试 LMMS 的音乐家有一个建议：使用插件。对于 [chiptune][14]式音乐，我们推荐 [sfxr][15]、[BitInvader][16] 和 [FreeBoy][17]。对于其它风格，[ZynAddSubFX][18] 是一个好的选择。它配备了各种合成仪器，可以根据您的需要进行更改。 + +### 图形工具 + +#### Tiled + +在开放源码游戏开发中，[Tiled][19] 是一个流行的贴片地图编辑器。我们使用它为来为我们在游戏场景中组合连续的、复古式的背景。 + +![](https://opensource.com/sites/default/files/u128651/tiled.png) + +Tiled 可以导出地图为 XML、JSON 或普通的图片。它是稳定的、跨平台的。 + +Tiled 的功能之一允许你在地图上定义和放置随意的游戏对象，例如硬币和提升道具，但在 jam 期间我们没有使用它。你需要做的全部是以贴片集的方式加载对象的图像，然后使用“插入平铺”来放置它们。 + +一般来说，对于需要一个地图编辑器的项目，Tiled 是我们所推荐的软件中一个不可或缺的部分。 + +#### Piskel + +[Piskel][20] 是一个像素艺术编辑器，它的源文件代码以 [Apache 2.0 协议][21] 发布。在这次 Jam 期间，们的大多数的图像资源都使用 Piskel 来处理，我们当然也将在未来的工程中使用它。 + +在这个 Jam 期间，Piskel 极大地帮助我们的两个功能是洋葱皮Onion skin和精灵序列图spritesheet导出。 + +##### 洋葱皮 + +洋葱皮功能将使 Piskel 以虚影显示你编辑的动画的前一帧和后一帧的，像这样: + +![](https://opensource.com/sites/default/files/u128651/onionshow.gif) + +洋葱皮是很方便的，因为它适合作为一个绘制指引和帮助你在整个动画进程中保持角色的一致形状和体积。 要启用它，只需单击屏幕右上角预览窗口下方的洋葱形图标即可。 + +![](https://opensource.com/sites/default/files/u128651/onionenable.png) + +##### 精灵序列图导出 + +Piskel 将动画导出为精灵序列图的能力也非常有用。精灵序列图是一个包含动画所有帧的光栅图像。例如，这是我们从 Piskel 导出的精灵序列图： + +![](https://opensource.com/sites/default/files/u128651/sprite-artist.png) + +该精灵序列图包含两帧。一帧位于图像的上半部分，另一帧位于图像的下半部分。精灵序列图通过从单个文件加载整个动画，大大简化了游戏的代码。这是上面精灵序列图的动画版本： + +![](https://opensource.com/sites/default/files/u128651/sprite-artist-anim.gif) + +##### Unpiskel.py + +在 Jam 期间，我们很多次想批量转换 Piskel 文件到 PNG 文件。由于 Piskel 文件格式基于 JSON，我们写一个基于 GPLv3 协议的名为 [unpiskel.py][22] 的 Python 小脚本来做转换。 + +它像这样被调用的： + +``` +python unpiskel.py input.piskel +``` + +这个脚本将从一个 Piskel 文件（这里是 `input.piskel`）中提取 PNG 数据帧和图层，并将它们各自存储。这些文件采用模式 `NAME_XX_YY.png` 命名，在这里 `NAME` 是 Piskel 文件的缩减名称，`XX` 是帧的编号，`YY` 是层的编号。 + +因为脚本可以从一个 shell 中调用，它可以用在整个文件列表中。 + +``` +for f in *.piskel; do python unpiskel.py "$f"; done +``` + +### Python、Pygame 和 cx_Freeze + +#### Python 和 Pygame + +我们使用 [Python][23] 语言来制作我们的游戏。它是一个脚本语言，通常被用于文本处理和桌面应用程序开发。它也可以用于游戏开发，例如像 [Angry Drunken Dwarves][24] 和 [Ren'Py][25] 这样的项目所展示的。这两个项目都使用一个称为 [Pygame][26] 的 Python 库来显示图形和产生声音，所以我们也决定在 Open Jam 中使用这个库。 + +Pygame 被证明是既稳定又富有特色，并且它对我们创建的街机式游戏来说是很棒的。在低分辨率时，库的速度足够快的，但是在高分辨率时，它只用 CPU 的渲染开始变慢。这是因为 Pygame 不使用硬件加速渲染。然而，开发者可以充分利用 OpenGL 基础设施的优势。 + +如果你正在寻找一个好的 2D 游戏编程库，Pygame 是值得密切注意的一个。它的网站有 [一个好的教程][27] 可以作为起步。务必看看它！ + +#### cx_Freeze + +准备发行我们的游戏是有趣的。我们知道，Windows 用户不喜欢装一套 Python，并且要求他们来安装它可能很过分。除此之外，他们也可能必须安装 Pygame，在 Windows 上，这不是一个简单的工作。 + +很显然：我们必须放置我们的游戏到一个更方便的格式中。很多其他的 Open Jam 参与者使用专有的游戏引擎 Unity，它能够使他们的游戏在网页浏览器中来玩。这使得它们非常方便地来玩。便利性是一个我们的游戏中根本不存在的东西。但是，感谢生机勃勃的 Python 生态系统，我们有选择。已有的工具可以帮助 Python 程序员将他们的游戏做成 Windows 上的发布版本。我们考虑过的两个工具是 [cx_Freeze][28] 和 [Pygame2exe][29]（它使用 [py2exe][30]）。我们最终决定用 cx_Freeze，因为它是跨平台的。 + +在 cx_Freeze 中，你可以把一个单脚本游戏打包成发布版本，只要在 shell 中运行一个命令，像这样： + +``` +cxfreeze main.py --target-dir dist +``` + +`cxfreeze` 的这个调用将把你的脚本（这里是 `main.py`）和在你系统上的 Python 解释器捆绑到到 `dist` 目录。一旦完成，你需要做的是手动复制你的游戏的数据文件到 `dist` 目录。你将看到，`dist` 目录包含一个可以运行来开始你的游戏的可执行文件。 + +这里有使用 cx_Freeze 的更复杂的方法，允许你自动地复制数据文件，但是我们发现简单的调用 `cxfreeze` 足够满足我们的需要。感谢这个工具，我们使我们的游戏玩起来更便利一些。 + +### 庆祝开源 + +Open Jam 是庆祝开源模式的软件开发的重要活动。这是一个分析开源工具的当前状态和我们在未来工作中需求的一个机会。对于游戏开发者探求其工具的使用极限，学习未来游戏开发所必须改进的地方，游戏 Jam 或许是最好的时机。 + +开源工具使人们能够在不损害自由的情况下探索自己的创造力，而无需预先投入资金。虽然我们可能不会成为专业的游戏开发者，但我们仍然能够通过我们的简短的实验性游戏 [Mark My Words][5] 获得一点点体验。它是一个以语言学为主题的游戏，描绘了虚构的书写系统在其历史中的演变。还有很多其他不错的作品提交给了 Open Jam，它们都值得一试。 真的，[去看看][31]！ + +在本文结束前，我们想要感谢所有的 [参加俱乐部的成员][32]，使得这次经历真正的有价值。我们也想要感谢 [Michael Clayton][33]、[Jared Sprague][34] 和 [Opensource.com][35] 主办 Open Jam。简直酷毙了。 + +现在，我们对读者提出了一些问题。你是一个 FOSS 游戏开发者吗？你选择的工具是什么？务必在下面留下一个评论！ + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/1/graphics-music-tools-game-dev + +作者：[Charlie Murphy][a] +译者：[robsean](https://github.com/robsean) +校对：[wxy](https://github.com/wxy) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/rsg167 +[1]:http://mugeeks.org/ +[2]:https://itch.io/jam/open-jam-1 +[3]:https://opensource.com/article/17/8/open-jam-announcement +[4]:https://opensource.com/article/17/11/open-jam +[5]:https://mugeeksalpha.itch.io/mark-omy-words +[6]:http://milkytracker.titandemo.org/ +[7]:https://en.wikipedia.org/wiki/Music_tracker +[8]:https://creativecommons.org/ +[9]:https://freesound.org/ +[10]:http://ccmixter.org/view/media/home +[11]:http://milkytracker.titandemo.org/documentation/ +[12]:https://github.com/milkytracker/MilkyTracker/wiki/MilkyTracker-Guide +[13]:https://lmms.io/ +[14]:https://en.wikipedia.org/wiki/Chiptune +[15]:https://github.com/grimfang4/sfxr +[16]:https://lmms.io/wiki/index.php?title=BitInvader +[17]:https://lmms.io/wiki/index.php?title=FreeBoy +[18]:http://zynaddsubfx.sourceforge.net/ +[19]:http://www.mapeditor.org/ +[20]:https://www.piskelapp.com/ +[21]:https://github.com/piskelapp/piskel/blob/master/LICENSE +[22]:https://raw.githubusercontent.com/MUGeeksandGadgets/MarkMyWords/master/tools/unpiskel.py +[23]:https://www.python.org/ +[24]:https://www.sacredchao.net/~piman/angrydd/ +[25]:https://renpy.org/ +[26]:https://www.Pygame.org/ +[27]:http://Pygame.org/docs/tut/PygameIntro.html +[28]:https://anthony-tuininga.github.io/cx_Freeze/ +[29]:https://Pygame.org/wiki/Pygame2exe +[30]:http://www.py2exe.org/ +[31]:https://itch.io/jam/open-jam-1/entries +[32]:https://github.com/MUGeeksandGadgets/MarkMyWords/blob/3e1e8aed12ebe13acccf0d87b06d4f3bd124b9db/README.md#credits +[33]:https://twitter.com/mwcz +[34]:https://twitter.com/caramelcode +[35]:https://opensource.com/ diff --git a/published/201812/20180131 For your first HTML code lets help Batman write a love letter.md b/published/201812/20180131 For your first HTML code lets help Batman write a love letter.md new file mode 100644 index 0000000000..4272904f5c --- /dev/null +++ b/published/201812/20180131 For your first HTML code lets help Batman write a love letter.md @@ -0,0 +1,869 @@ +编写你的第一行 HTML 代码，来帮助蝙蝠侠写一封情书 +====== + +![](https://cdn-images-1.medium.com/max/1000/1*kZxbQJTdb4jn_frfqpRg9g.jpeg) + +在一个美好的夜晚，你的肚子拒绝消化你在晚餐吃的大块披萨，所以你不得不在睡梦中冲进洗手间。 + +在浴室里，当你在思考为什么会发生这种情况时，你听到一个来自通风口的低沉声音：“嘿，我是蝙蝠侠。” + +这时，你会怎么做呢？ + +在你恐慌并处于关键时刻之前，蝙蝠侠说：“我需要你的帮助。我是一个超级极客，但我不懂 HTML。我需要用 HTML 写一封情书，你愿意帮助我吗？” + +谁会拒绝蝙蝠侠的请求呢，对吧？所以让我们用 HTML 来写一封蝙蝠侠的情书。 + +### 你的第一个 HTML 文件 + +HTML 网页与你电脑上的其它文件一样。就同一个 .doc 文件以 MS Word 打开，.jpg 文件在图像查看器中打开一样，一个 .html 文件在浏览器中打开。 + +那么，让我们来创建一个 .html 文件。你可以在 Notepad 或其它任何编辑器中完成此任务，但我建议使用 VS Code。[在这里下载并安装 VS Code][2]。它是免费的，也是我唯一喜欢的微软产品。 + +在系统中创建一个目录，将其命名为 “HTML Practice”（不带引号）。在这个目录中，再创建一个名为 “Batman's Love Letter”（不带引号）的目录，这将是我们的项目根目录。这意味着我们所有与这个项目相关的文件都会在这里。 + +打开 VS Code，按下 `ctrl+n` 创建一个新文件，按下 `ctrl+s` 保存文件。切换到 “Batman's Love Letter” 文件夹并将其命名为 “loveletter.html”，然后单击保存。 + +现在，如果你在文件资源管理器中双击它，它将在你的默认浏览器中打开。我建议使用 Firefox 来进行 web 开发，但 Chrome 也可以。 + +让我们将这个过程与我们已经熟悉的东西联系起来。还记得你第一次拿到电脑吗？我做的第一件事是打开 MS Paint 并绘制一些东西。你在 Paint 中绘制一些东西并将其另存为图像，然后你可以在图像查看器中查看该图像。之后，如果要再次编辑该图像，你在 Paint 中重新打开它，编辑并保存它。 + +我们目前的流程非常相似。正如我们使用 Paint 创建和编辑图像一样，我们使用 VS Code 来创建和编辑 HTML 文件。就像我们使用图像查看器查看图像一样，我们使用浏览器来查看我们的 HTML 页面。 + +### HTML 中的段落 + +我们有一个空的 HTML 文件，以下是蝙蝠侠想在他的情书中写的第一段。 + +“After all the battles we fought together, after all the difficult times we saw together, and after all the good and bad moments we’ve been through, I think it’s time I let you know how I feel about you.” + +复制这些到 VS Code 中的 loveletter.html。单击 “View -> Toggle Word Wrap (alt+z)” 自动换行。 + +保存并在浏览器中打开它。如果它已经打开，单击浏览器中的刷新按钮。 + +瞧！那是你的第一个网页！ + +我们的第一段已准备就绪，但这不是在 HTML 中编写段落的推荐方法。我们有一种特定的方法让浏览器知道一个文本是一个段落。 + +如果你用 `

` 和 `

` 来包裹文本，那么浏览器将识别 `

` 和 `

` 中的文本是一个段落。我们这样做： + +``` +

After all the battles we fought together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you.

+``` + +通过在 `

` 和 `

`中编写段落，你创建了一个 HTML 元素。一个网页就是 HTML 元素的集合。 + +让我们首先来认识一些术语：`

` 是开始标签，`

` 是结束标签，“p” 是标签名称。元素开始和结束标签之间的文本是元素的内容。 + +### “style” 属性 + +在上面，你将看到文本覆盖屏幕的整个宽度。 + +我们不希望这样。没有人想要阅读这么长的行。让我们设定段落宽度为 550px。 + +我们可以通过使用元素的 `style` 属性来实现。你可以在其 `style` 属性中定义元素的样式（例如，在我们的示例中为宽度）。以下行将在 `p` 元素上创建一个空样式属性： + +``` +

...

+``` + +你看到那个空的 `""` 了吗？这就是我们定义元素外观的地方。现在我们要将宽度设置为 550px。我们这样做： + +``` +

+ After all the battles we fought together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

+``` + +我们将 `width` 属性设置为 `550px`，用冒号 `:` 分隔，以分号 `;` 结束。 + +另外，注意我们如何将 `

` 和 `

` 放在单独的行中，文本内容用一个制表符缩进。像这样设置代码使其更具可读性。 + +### HTML 中的列表 + +接下来，蝙蝠侠希望列出他所钦佩的人的一些优点，例如： + +``` +You complete my darkness with your light. I love: +- the way you see good in the worst things +- the way you handle emotionally difficult situations +- the way you look at Justice +I have learned a lot from you. You have occupied a special place in my heart over time. +``` + +这看起来很简单。 + +让我们继续，在 `

` 下面复制所需的文本： + +``` +

+ After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

+

+ You complete my darkness with your light. I love: + - the way you see good in the worse + - the way you handle emotionally difficult situations + - the way you look at Justice + I have learned a lot from you. You have occupied a special place in my heart over the time. +

+``` + +保存并刷新浏览器。 + +![](https://cdn-images-1.medium.com/max/1000/1*M0Ae5ZpRTucNyucfaaz4uw.jpeg) + +哇！这里发生了什么，我们的列表在哪里？ + +如果你仔细观察，你会发现没有显示换行符。在代码中我们在新的一行中编写列表项，但这些项在浏览器中显示在一行中。 + +如果你想在 HTML（新行）中插入换行符，你必须使用 `
`。让我们来使用 `
`，看看它长什么样： + +``` +

+ After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

+

+ You complete my darkness with your light. I love:
+ - the way you see good in the worse
+ - the way you handle emotionally difficult situations
+ - the way you look at Justice
+ I have learned a lot from you. You have occupied a special place in my heart over the time. +

+``` + +保存并刷新： + +![](https://cdn-images-1.medium.com/max/1000/1*Mj4Sr_jUliidxFpEtu0pXw.jpeg) + +好的，现在它看起来就像我们想要的那样！ + +另外，注意我们没有写一个 `
`。有些标签不需要结束标签（它们被称为自闭合标签）。 + +还有一件事：我们没有在两个段落之间使用 `
`，但第二个段落仍然是从一个新行开始，这是因为 `

` 元素会自动插入换行符。 + +我们使用纯文本编写列表，但是有两个标签可以供我们使用来达到相同的目的：`

    ` and `
  • `。 + +让我们解释一下名字的意思：ul 代表无序列表Unordered List，li 代表列表项目List Item。让我们使用它们来展示我们的列表： + +``` +

    + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

    +``` + +``` +

    + You complete my darkness with your light. I love: +

      +
    • the way you see good in the worse
      • +
    • the way you handle emotionally difficult situations
      • +
    • the way you look at Justice
      • +
    + I have learned a lot from you. You have occupied a special place in my heart over the time. +

    +``` + +在复制代码之前，注意差异部分： + +* 我们删除了所有的 `
    `，因为每个 `
  • ` 会自动显示在新行中 +* 我们将每个列表项包含在 `
  • ` 和 `
    • ` 之间 +* 我们将所有列表项的集合包裹在 `
      ` 和 `
    ` 之间 +* 我们没有像 `

    ` 元素那样定义 `

      ` 元素的宽度。这是因为 `
        ` 是 `

        ` 的子节点，`

        ` 已经被约束到 550px，所以 `

          ` 不会超出这个范围。 + +让我们保存文件并刷新浏览器以查看结果： + +![](https://cdn-images-1.medium.com/max/1000/1*aPlMpYVZESPwgUO3Iv-qCA.jpeg) + +你会立即注意到在每个列表项之前显示了重点标志。我们现在不需要在每个列表项之前写 “-”。 + +经过仔细检查，你会注意到最后一行超出 550px 宽度。这是为什么？因为 HTML 不允许 `
            ` 元素出现在 `

            ` 元素中。让我们将第一行和最后一行放在单独的 `

            ` 元素中： + +``` +

            + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

            +``` + +``` +

            + You complete my darkness with your light. I love: +

            +``` + +``` +
              +
            • the way you see good in the worse
              • +
            • the way you handle emotionally difficult situations
              • +
            • the way you look at Justice
              • +
            +``` + +``` +

            + I have learned a lot from you. You have occupied a special place in my heart over the time. +

            +``` + +保存并刷新。 + +注意，这次我们还定义了 `
              ` 元素的宽度。那是因为我们现在已经将 `
                ` 元素放在了 `

                ` 元素之外。 + +定义情书中所有元素的宽度会变得很麻烦。我们有一个特定的元素用于此目的：`

                ` 元素。一个 `
                ` 元素就是一个通用容器，用于对内容进行分组，以便轻松设置样式。 + +让我们用 `
                ` 元素包装整个情书，并为其赋予宽度：550px 。 + +``` +
                +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +
                +``` + +棒极了，我们的代码现在看起来简洁多了。 + +### HTML 中的标题 + +到目前为止，蝙蝠侠对结果很高兴，他希望在情书上标题。他想写一个标题： “Bat Letter”。当然，你已经看到这个名字了，不是吗？:D + +你可以使用 `

                `、`

                `、`

                `、`

                `、`

                ` 和 `
                ` 标签来添加标题，`

                ` 是最大的标题和最主要的标题，`

                ` 是最小的标题。 + +![](https://cdn-images-1.medium.com/max/1000/1*Ud-NzfT-SrMgur1WX4LCkQ.jpeg) + +让我们在第二段之前使用 `

                ` 做主标题和一个副标题： + +``` +
                +

                Bat Letter

                +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +
                +``` + +保存，刷新。 + +![](https://cdn-images-1.medium.com/max/1000/1*rzyIl-gHug3nQChqfscU3w.jpeg) + +### HTML 中的图像 + +我们的情书尚未完成，但在继续之前，缺少一件大事：蝙蝠侠标志。你见过是蝙蝠侠的东西但没有蝙蝠侠的标志吗？ + +并没有。 + +所以，让我们在情书中添加一个蝙蝠侠标志。 + +在 HTML 中包含图像就像在一个 Word 文件中包含图像一样。在 MS Word 中，你到 “菜单 -> 插入 -> 图像 -> 然后导航到图像位置为止 -> 选择图像 -> 单击插入”。 + +在 HTML 中，我们使用 `` 标签让浏览器知道我们需要加载的图像，而不是单击菜单。我们在 `src` 属性中写入文件的位置和名称。如果图像在项目根目录中，我们可以简单地在 `src` 属性中写入图像文件的名称。 + +在我们深入编码之前，从[这里][3]下载蝙蝠侠标志。你可能希望裁剪图像中的额外空白区域。复制项目根目录中的图像并将其重命名为 “bat-logo.jpeg”。 + +``` +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +
                +``` + +我们在第 3 行包含了 `` 标签。这个标签也是一个自闭合的标签，所以我们不需要写 ``。在 `src` 属性中，我们给出了图像文件的名称。这个名称应与图像名称完全相同，包括扩展名（.jpeg）及其大小写。 + +保存并刷新，查看结果。 + +![](https://cdn-images-1.medium.com/max/1000/1*uMNWAISOACJlzDOONcrGXw.jpeg) + +该死的！刚刚发生了什么？ + +当使用 `` 标签包含图像时，默认情况下，图像将以其原始分辨率显示。在我们的例子中，图像比 550px 宽得多。让我们使用 `style` 属性定义它的宽度： + + +``` +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +
                +``` + +你会注意到，这次我们定义宽度使用了 “%” 而不是 “px”。当我们在 “%” 中定义宽度时，它将占据父元素宽度的百分比。因此，100% 的 550px 将为我们提供 550px。 + +保存并刷新，查看结果。 + +![](https://cdn-images-1.medium.com/max/1000/1*5c0ngx3BFVlyyP6UNtfYyg.jpeg) + +太棒了！这让蝙蝠侠的脸露出了羞涩的微笑 :)。 + +### HTML 中的粗体和斜体 + +现在蝙蝠侠想在最后几段中承认他的爱。他有以下文本供你用 HTML 编写： + +“I have a confession to make + +It feels like my chest _does_ have a heart. You make my heart beat. Your smile brings a smile to my face, your pain brings pain to my heart. + +I don’t show my emotions, but I think this man behind the mask is falling for you.” + +当阅读到这里时，你会问蝙蝠侠：“等等，这是给谁的？”蝙蝠侠说： + +“这是给超人的。” + +![](https://cdn-images-1.medium.com/max/1000/1*UNDvfIZQJ1Q_goHc-F-IPA.jpeg) + +你说：哦！我还以为是给神奇女侠的呢。 + +蝙蝠侠说：不，这是给超人的，请在最后写上 “I love you Superman.”。 + +好的，我们来写： + + +``` +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                +``` + +这封信差不多完成了，蝙蝠侠另外想再做两次改变。蝙蝠侠希望在最后段落的第一句中的 “does” 一词是斜体，而 “I love you Superman” 这句话是粗体的。 + +我们使用 `` 和 `` 以斜体和粗体显示文本。让我们来更新这些更改： + +``` +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                +``` + +![](https://cdn-images-1.medium.com/max/1000/1*6hZdQJglbHUcEEHzouk2eA.jpeg) + +### HTML 中的样式 + +你可以通过三种方式设置样式或定义 HTML 元素的外观： + +* 内联样式：我们使用元素的 `style` 属性来编写样式。这是我们迄今为止使用的，但这不是一个好的实践。 +* 嵌入式样式：我们在由 `` 包裹的 “style” 元素中编写所有样式。 +* 链接样式表：我们在具有 .css 扩展名的单独文件中编写所有元素的样式。此文件称为样式表。 + +让我们来看看如何定义 `
                ` 的内联样式： + +``` +
                +``` + +我们可以在 `` 里面写同样的样式： + +``` +div{ + width:550px; +} +``` + +在嵌入式样式中，我们编写的样式是与元素分开的。所以我们需要一种方法来关联元素及其样式。第一个单词 “div” 就做了这样的活。它让浏览器知道花括号 `{...}` 里面的所有样式都属于 “div” 元素。由于这种语法确定要应用样式的元素，因此它称为一个选择器。 + +我们编写样式的方式保持不变：属性（`width`）和值（`550px`）用冒号（`:`）分隔，以分号（`;`）结束。 + +让我们从 `
                ` 和 `` 元素中删除内联样式，将其写入 ` +``` + +``` +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                +``` + +保存并刷新，结果应保持不变。 + +但是有一个大问题，如果我们的 HTML 文件中有多个 `
                ` 和 `` 元素该怎么办？这样我们在 ` +``` + +``` +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +``` + +``` +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                +``` + +HTML 已经准备好了嵌入式样式。 + +但是，你可以看到，随着我们包含越来越多的样式，`` 将变得很大。这可能很快会混乱我们的主 HTML 文件。 + +因此，让我们更进一步，通过将 ``。 + +我们需要使用 HTML 文件中的 `` 标签来将新创建的 CSS 文件链接到 HTML 文件。以下是我们如何做到这一点： + +``` + +``` + +我们使用 `` 元素在 HTML 文档中包含外部资源，它主要用于链接样式表。我们使用的三个属性是： + +* `rel`：关系。链接文件与文档的关系。具有 .css 扩展名的文件称为样式表，因此我们保留 rel=“stylesheet”。 +* `type`：链接文件的类型；对于一个 CSS 文件来说它是 “text/css”。 +* `href`：超文本参考。链接文件的位置。 + +link 元素的结尾没有 ``。因此，`` 也是一个自闭合的标签。 + +``` + +``` + +如果只是得到一个女朋友，那么很容易：D + +可惜没有那么简单，让我们继续前进。 + +这是我们 “loveletter.html” 的内容： + +``` + +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                +``` + +“style.css” 内容： + +``` +#letter-container{ + width:550px; +} +#header-bat-logo{ + width:100%; +} +``` + +保存文件并刷新，浏览器中的输出应保持不变。 + +### 一些手续 + +我们的情书已经准备好给蝙蝠侠，但还有一些正式的片段。 + +与其他任何编程语言一样，HTML 自出生以来（1990 年）经历过许多版本，当前版本是 HTML5。 + +那么，浏览器如何知道你使用哪个版本的 HTML 来编写页面呢？要告诉浏览器你正在使用 HTML5，你需要在页面顶部包含 ``。对于旧版本的 HTML，这行不同，但你不需要了解它们，因为我们不再使用它们了。 + +此外，在之前的 HTML 版本中，我们曾经将整个文档封装在 `` 标签内。整个文件分为两个主要部分：头部在 `` 里面，主体在 `` 里面。这在 HTML5 中不是必须的，但由于兼容性原因，我们仍然这样做。让我们用 ``, ``、 `` 和 `` 更新我们的代码： + +``` + + + + + + +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                + + +``` + +主要内容在 `` 里面，元信息在 `` 里面。所以我们把 `
                ` 保存在 `` 里面并加载 `` 里面的样式表。 + +保存并刷新，你的 HTML 页面应显示与之前相同的内容。 + +### HTML 的标题 + +我发誓，这是最后一次改变。 + +你可能已经注意到选项卡的标题正在显示 HTML 文件的路径： + +![](https://cdn-images-1.medium.com/max/1000/1*PASKm4ji29hbcZXVSP8afg.jpeg) + +我们可以使用 `` 标签来定义 HTML 文件的标题。标题标签也像链接标签一样在 `<head>` 内部。让我们我们在标题中加上 “Bat Letter”： + +``` +<!DOCTYPE html> +<html> +<head> + <title>Bat Letter + + + +
                +

                Bat Letter

                + +

                + After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. +

                +

                You are the light of my life

                +

                + You complete my darkness with your light. I love: +

                +
                  +
                • the way you see good in the worse
                  • +
                • the way you handle emotionally difficult situations
                  • +
                • the way you look at Justice
                  • +
                +

                + I have learned a lot from you. You have occupied a special place in my heart over the time. +

                +

                I have a confession to make

                +

                + It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. +

                +

                + I don't show my emotions, but I think this man behind the mask is falling for you. +

                +

                I love you Superman.

                +

                + Your not-so-secret-lover,
                + Batman +

                +
                + + +``` + +保存并刷新，你将看到在选项卡上显示的是 “Bat Letter” 而不是文件路径。 + +蝙蝠侠的情书现在已经完成。 + +恭喜！你用 HTML 制作了蝙蝠侠的情书。 + +![](https://cdn-images-1.medium.com/max/1000/1*qC8qtrYtxAB6cJfm9aVOOQ.jpeg) + +### 我们学到了什么 + +我们学习了以下新概念： + + * 一个 HTML 文档的结构 + * 在 HTML 中如何写元素（`

                `） + * 如何使用 style 属性在元素内编写样式（这称为内联样式，尽可能避免这种情况） + * 如何在 `` 中编写元素的样式（这称为嵌入式样式） + * 在 HTML 中如何使用 `` 在单独的文件中编写样式并链接它（这称为链接样式表） + * 什么是标签名称，属性，开始标签和结束标签 + * 如何使用 id 属性为一个元素赋予 id + * CSS 中的标签选择器和 id 选择器 + +我们学习了以下 HTML 标签： + + * `

                `：用于段落 + * `
                `：用于换行 + * `

                  `、`
                • `：显示列表 + * `
                  `：用于分组我们信件的元素 + * `

                  `、`

                  `：用于标题和子标题 + * ``：用于插入图像 + * ``、``：用于粗体和斜体文字样式 + * `. - -* Linked stylesheet: We write styles of all the elements in a separate file with .css extension. This file is called Stylesheet. - -Let’s have a look at how we defined the inline style of the “div” until now: - -``` -
                  -``` - -We can write this same style inside `` like this: - -``` -div{ - width:550px; -} -``` - -In embedded styling, the styles we write are separate from the elements. So we need a way to relate the element and its style. The first word “div” does exactly that. It lets the browser know that whatever style is inside the curly braces `{…}` belongs to the “div” element. Since this phrase determines which element to apply the style to, it’s called a selector. - -The way we write style remains same: property(width) and value(550px) separated by a colon(:) and ended by a semicolon(;). - -Let’s remove inline style from our “div” and “img” element and write it inside the ` -``` - -``` -
                  -

                  Bat Letter

                  - -

                  - After all the battles we faught together, after all the difficult times we saw together, after all the good and bad moments we've been through, I think it's time I let you know how I feel about you. -

                  -``` - -``` -

                  You are the light of my life

                  -

                  - You complete my darkness with your light. I love: -

                  -
                    -
                  • the way you see good in the worse
                    • -
                  • the way you handle emotionally difficult situations
                    • -
                  • the way you look at Justice
                    • -
                  -

                  - I have learned a lot from you. You have occupied a special place in my heart over the time. -

                  -

                  I have a confession to make

                  -

                  - It feels like my chest does have a heart. You make my heart beat. Your smile brings smile on my face, your pain brings pain to my heart. -

                  -

                  - I don't show my emotions, but I think this man behind the mask is falling for you. -

                  -

                  I love you Superman.

                  -

                  - Your not-so-secret-lover,
                  - Batman -

                  -
                  -``` - -Save and refresh, and the result should remain the same. - -There is one big problem though — what if there is more than one “div” and “img” element in our HTML file? The styles that we defined for div and img inside the “style” element will apply to every div and img on the page. - -If you add another div in your code in the future, then that div will also become 550px wide. We don’t want that. - -We want to apply our styles to the specific div and img that we are using right now. To do this, we need to give our div and img element unique ids. Here’s how you can give an id to an element using its “id” attribute: - -``` -
                  -``` - -and here’s how to use th diff --git a/sources/tech/20180226 -Getting to Done- on the Linux command line.md b/sources/tech/20180226 -Getting to Done- on the Linux command line.md deleted file mode 100644 index c325a0d884..0000000000 --- a/sources/tech/20180226 -Getting to Done- on the Linux command line.md +++ /dev/null @@ -1,126 +0,0 @@ -'Getting to Done' on the Linux command line -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/osdc_terminals.png?itok=CfBqYBah) -There is a lot of talk about getting things done at the command line. How many articles are there about using obscure flags with `ls`, nifty regular expressions with Sed and Awk, and how to parse out lots of text with Perl? That isn't what this is about. - -This is about [Getting _to_ Done][1], making sure that the stuff we have to do actually gets tracked and done using tools that don't require a graphical desktop, a web browser, or an internet connection. To do this, we'll look at four ways of tracking your to-do list: plaintext files, Todo.txt, TaskWarrior, and Org-mode. - -### Plain (and simple) text - - -![plaintext][3] - -I like to use Vim, but you can use Nano too. - -The most straightforward way to manage your to-do list is using a plaintext file in your editor of choice. Just open an empty file and add tasks, one per line. When you are done, delete the line. Simple, effective, and it doesn't matter what you use to do it. There are a couple of drawbacks to this method, though. Once you delete a line and save the file, it is gone forever. That can be a problem if you have to report on what you have done this week or last week. And while using a simple file is flexible, it can also get cluttered really easily. - -### Todo.txt: Plaintext leveled up - - -![todo.txt screen][5] - -Neat, organized, and easy to use - -That leads us to the [Todo.txt][6] file format and application. Installation is simple—[download][7] the latest release from GitHub and run `sudo make install` from the unpacked archive. - - -![Installing todo.txt][9] - -It works from a Git clone as well. - -Todo.txt makes it very easy to add tasks, list tasks, and mark them as done: - -| `todo.sh add "Some Task"` | add "Some Task" to my todo list | -| `todo.sh ls` | list all my tasks | -| `todo.sh ls due:2018-02-15` | list all tasks due on February 15, 2018 | -| `todo.sh do 3` | mark task number 3 as "done" | - -The actual list is still in plaintext, and you can edit it with your favorite text editor as long as you follow the [correct format][10]. - -There is also a very robust help built into the application. - - -![Syntax highlighting in todo.txt][12] - -You can even get syntax highlighting. - -There is also a large selection of add-ons, as well as specifications for writing your own. There are even browser extensions, mobile apps, and desktop apps that support the Todo.txt format. - - -![GNOME extensions in todo.txt][14] - -Even GNOME extensions. - -The biggest drawback to Todo.txt is the lack of an automatic or built-in synchronization mechanism. Most (if not all) of the browser extensions and mobile apps require Dropbox to perform synchronization between the app and the copy on your desktop. If you would like something with sync built-in, we have... - -### Taskwarrior: Now we're cooking with Python - -[Taskwarrior][15] is a Python application with many of the same features as Todo.txt. However, it stores the data in a database and has built-in synchronization capabilities. It also keeps track of what is next, notes how old tasks are, and will warn you if you have something more important to do than what you just did. - -[Installation][16] of Taskwarrior can be done either with your distribution's package manager, through Python's `pip` utility, or built from source. Using it is also pretty straightforward, with commands similar to Todo.txt: - -| `task add "Some Task"` | Add "Some Task" to the list | -| `task list` | List all tasks | -| `task list due ``:today` | List all tasks due on today's date | -| `task do 3` | Complete task number 3 | - -Taskwarrior also has some pretty nice text user interfaces. - -![Taskwarrior in Vit][18] - -I like Vit, which was inspired by Vim. - -Unlike Todo.txt, Taskwarrior can synchronize with a local or remote server. A very basic synchronization server called `taskd` is available if you wish to run your own, and there are several services available if you do not. - -Taskwarrior also has a thriving and extensive ecosystem of add-ons and extensions, as well as mobile and desktop apps. - -![Taskwarrior on GNOME][20] - -Taskwarrior looks really nice on GNOME. - -The only disadvantage to Taskwarrior is that, unlike the other programs listed here, you cannot directly modify the to-do list itself. You can export the task list to various formats, modify the export, and then re-import the files, but it is a lot clunkier than just opening the file directly in a text editor. - -Which brings us to the most powerful of them all... - -### Emacs Org-mode: Hulk smash tasks - -![Org-mode][22] - -Emacs has everything. - -Emacs [Org-mode][23] is by far the most powerful, most flexible open source to-do list manager out there. It supports multiple files, uses plaintext, is almost infinitely customizable, and understands calendars, due dates, and schedules. It is also significantly more complicated to set up than the other applications listed here. But once it is set up, it does everything the other applications do and more. If you are familiar with or a fan of [Bullet Journals][24], Org-mode is possibly the closest you can get on a computer. - -Org-mode will run anywhere Emacs runs, and there are a few mobile applications that can interact with it as well. Unfortunately, there are no desktop apps or browser extensions that support Org. Despite all that, Org-mode is still one of the best applications for tracking your to-do list, since it is so very powerful. - -### Choose your tool - -In the end, the goal of all these programs is to help you track what you need to do and make sure you don't forget to do something. While they all have the same basic functions, choosing which one is right for you depends on a lot of factors. Do you want synchronization built-in or not? Do you need a mobile app? Do any of the add-ons include a "must have" feature? Whatever your choice, remember that the program alone cannot make you more organized, but it can help. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/2/getting-to-done-agile-linux-command-line - -作者：[Kevin Sonney][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: -[1]:https://www.scruminc.com/getting-done/ -[3]:https://opensource.com/sites/default/files/u128651/plain-text.png (plaintext) -[5]:https://opensource.com/sites/default/files/u128651/todo-txt.png (todo.txt screen) -[6]:http://todotxt.org/ -[7]:https://github.com/todotxt/todo.txt-cli/releases -[9]:https://opensource.com/sites/default/files/u128651/todo-txt-install.png (Installing todo.txt) -[10]:https://github.com/todotxt/todo.txt -[12]:https://opensource.com/sites/default/files/u128651/todo-txt-vim.png (Syntax highlighting in todo.txt) -[14]:https://opensource.com/sites/default/files/u128651/tod-txt-gnome.png (GNOME extensions in todo.txt) -[15]:https://taskwarrior.org/ -[16]:https://taskwarrior.org/download/ -[18]:https://opensource.com/sites/default/files/u128651/taskwarrior-vit.png (Taskwarrior in Vit) -[20]:https://opensource.com/sites/default/files/u128651/taskwarrior-gnome.png (Taskwarrior on GNOME) -[22]:https://opensource.com/sites/default/files/u128651/emacs-org-mode.png (Org-mode) -[23]:https://orgmode.org/ -[24]:http://bulletjournal.com/ diff --git a/sources/tech/20180307 Protecting Code Integrity with PGP - Part 4- Moving Your Master Key to Offline Storage.md b/sources/tech/20180307 Protecting Code Integrity with PGP - Part 4- Moving Your Master Key to Offline Storage.md deleted file mode 100644 index df00e7e05e..0000000000 --- a/sources/tech/20180307 Protecting Code Integrity with PGP - Part 4- Moving Your Master Key to Offline Storage.md +++ /dev/null @@ -1,167 +0,0 @@ -Protecting Code Integrity with PGP — Part 4: Moving Your Master Key to Offline Storage -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/industry-1920.jpg?itok=gI3QraS8) -In this tutorial series, we're providing practical guidelines for using PGP. You can catch up on previous articles here: - -[Part 1: Basic Concepts and Tools][1] - -[Part 2: Generating Your Master Key][2] - -[Part 3: Generating PGP Subkeys][3] - -Here in part 4, we continue the series with a look at how and why to move your master key from your home directory to offline storage. Let's get started. - -### Checklist - - * Prepare encrypted detachable storage (ESSENTIAL) - - * Back up your GnuPG directory (ESSENTIAL) - - * Remove the master key from your home directory (NICE) - - * Remove the revocation certificate from your home directory (NICE) - - - - -#### Considerations - -Why would you want to remove your master [C] key from your home directory? This is generally done to prevent your master key from being stolen or accidentally leaked. Private keys are tasty targets for malicious actors -- we know this from several successful malware attacks that scanned users' home directories and uploaded any private key content found there. - -It would be very damaging for any developer to have their PGP keys stolen -- in the Free Software world, this is often tantamount to identity theft. Removing private keys from your home directory helps protect you from such events. - -##### Back up your GnuPG directory - -**!!!Do not skip this step!!!** - -It is important to have a readily available backup of your PGP keys should you need to recover them (this is different from the disaster-level preparedness we did with paperkey). - -##### Prepare detachable encrypted storage - -Start by getting a small USB "thumb" drive (preferably two!) that you will use for backup purposes. You will first need to encrypt them: - -For the encryption passphrase, you can use the same one as on your master key. - -##### Back up your GnuPG directory - -Once the encryption process is over, re-insert the USB drive and make sure it gets properly mounted. Find out the full mount point of the device, for example by running the mount command (under Linux, external media usually gets mounted under /media/disk, under Mac it's /Volumes). - -Once you know the full mount path, copy your entire GnuPG directory there: -``` -$ cp -rp ~/.gnupg [/media/disk/name]/gnupg-backup - -``` - -(Note: If you get any Operation not supported on socket errors, those are benign and you can ignore them.) - -You should now test to make sure everything still works: -``` -$ gpg --homedir=[/media/disk/name]/gnupg-backup --list-key [fpr] - -``` - -If you don't get any errors, then you should be good to go. Unmount the USB drive and distinctly label it, so you don't blow it away next time you need to use a random USB drive. Then, put in a safe place -- but not too far away, because you'll need to use it every now and again for things like editing identities, adding or revoking subkeys, or signing other people's keys. - -##### Remove the master key - -The files in our home directory are not as well protected as we like to think. They can be leaked or stolen via many different means: - - * By accident when making quick homedir copies to set up a new workstation - - * By systems administrator negligence or malice - - * Via poorly secured backups - - * Via malware in desktop apps (browsers, pdf viewers, etc) - - * Via coercion when crossing international borders - - - - -Protecting your key with a good passphrase greatly helps reduce the risk of any of the above, but passphrases can be discovered via keyloggers, shoulder-surfing, or any number of other means. For this reason, the recommended setup is to remove your master key from your home directory and store it on offline storage. - -###### Removing your master key - -Please see the previous section and make sure you have backed up your GnuPG directory in its entirety. What we are about to do will render your key useless if you do not have a usable backup! - -First, identify the keygrip of your master key: -``` -$ gpg --with-keygrip --list-key [fpr] - -``` - -The output will be something like this: -``` -pub rsa4096 2017-12-06 [C] [expires: 2019-12-06] - 111122223333444455556666AAAABBBBCCCCDDDD - Keygrip = AAAA999988887777666655554444333322221111 -uid [ultimate] Alice Engineer -uid [ultimate] Alice Engineer -sub rsa2048 2017-12-06 [E] - Keygrip = BBBB999988887777666655554444333322221111 -sub rsa2048 2017-12-06 [S] - Keygrip = CCCC999988887777666655554444333322221111 - -``` - -Find the keygrip entry that is beneath the pub line (right under the master key fingerprint). This will correspond directly to a file in your home .gnupg directory: -``` -$ cd ~/.gnupg/private-keys-v1.d -$ ls -AAAA999988887777666655554444333322221111.key -BBBB999988887777666655554444333322221111.key -CCCC999988887777666655554444333322221111.key - -``` - -All you have to do is simply remove the .key file that corresponds to the master keygrip: -``` -$ cd ~/.gnupg/private-keys-v1.d -$ rm AAAA999988887777666655554444333322221111.key - -``` - -Now, if you issue the --list-secret-keys command, it will show that the master key is missing (the # indicates it is not available): -``` -$ gpg --list-secret-keys -sec# rsa4096 2017-12-06 [C] [expires: 2019-12-06] - 111122223333444455556666AAAABBBBCCCCDDDD -uid [ultimate] Alice Engineer -uid [ultimate] Alice Engineer -ssb rsa2048 2017-12-06 [E] -ssb rsa2048 2017-12-06 [S] - -``` - -##### Remove the revocation certificate - -Another file you should remove (but keep in backups) is the revocation certificate that was automatically created with your master key. A revocation certificate allows someone to permanently mark your key as revoked, meaning it can no longer be used or trusted for any purpose. You would normally use it to revoke a key that, for some reason, you can no longer control -- for example, if you had lost the key passphrase. - -Just as with the master key, if a revocation certificate leaks into malicious hands, it can be used to destroy your developer digital identity, so it's better to remove it from your home directory. -``` -cd ~/.gnupg/openpgp-revocs.d -rm [fpr].rev - -``` - -Next time, you'll learn how to secure your subkeys as well. Stay tuned. - -Learn more about Linux through the free ["Introduction to Linux" ][4]course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage - -作者：[Konstantin Ryabitsev][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/mricon -[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools -[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key -[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys -[4]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20180314 Protecting Code Integrity with PGP - Part 5- Moving Subkeys to a Hardware Device.md b/sources/tech/20180314 Protecting Code Integrity with PGP - Part 5- Moving Subkeys to a Hardware Device.md deleted file mode 100644 index ac862ff64e..0000000000 --- a/sources/tech/20180314 Protecting Code Integrity with PGP - Part 5- Moving Subkeys to a Hardware Device.md +++ /dev/null @@ -1,303 +0,0 @@ -Protecting Code Integrity with PGP — Part 5: Moving Subkeys to a Hardware Device -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/pgp-keys.jpg?itok=aS6IWGpq) - -In this tutorial series, we're providing practical guidelines for using PGP. If you missed the previous article, you can catch up with the links below. But, in this article, we'll continue our discussion about securing your keys and look at some tips for moving your subkeys to a specialized hardware device. - -[Part 1: Basic Concepts and Tools][1] - -[Part 2: Generating Your Master Key][2] - -[Part 3: Generating PGP Subkeys][3] - -[Part 4: Moving Your Master Key to Offline Storage][4] - -### Checklist - - * Get a GnuPG-compatible hardware device (NICE) - - * Configure the device to work with GnuPG (NICE) - - * Set the user and admin PINs (NICE) - - * Move your subkeys to the device (NICE) - - - - -### Considerations - -Even though the master key is now safe from being leaked or stolen, the subkeys are still in your home directory. Anyone who manages to get their hands on those will be able to decrypt your communication or fake your signatures (if they know the passphrase). Furthermore, each time a GnuPG operation is performed, the keys are loaded into system memory and can be stolen from there by sufficiently advanced malware (think Meltdown and Spectre). - -The best way to completely protect your keys is to move them to a specialized hardware device that is capable of smartcard operations. - -#### The benefits of smartcards - -A smartcard contains a cryptographic chip that is capable of storing private keys and performing crypto operations directly on the card itself. Because the key contents never leave the smartcard, the operating system of the computer into which you plug in the hardware device is not able to retrieve the private keys themselves. This is very different from the encrypted USB storage device we used earlier for backup purposes -- while that USB device is plugged in and decrypted, the operating system is still able to access the private key contents. Using external encrypted USB media is not a substitute to having a smartcard-capable device. - -Some other benefits of smartcards: - - * They are relatively cheap and easy to obtain - - * They are small and easy to carry with you - - * They can be used with multiple devices - - * Many of them are tamper-resistant (depends on manufacturer) - - - - -#### Available smartcard devices - -Smartcards started out embedded into actual wallet-sized cards, which earned them their name. You can still buy and use GnuPG-capable smartcards, and they remain one of the cheapest available devices you can get. However, actual smartcards have one important downside: they require a smartcard reader, and very few laptops come with one. - -For this reason, manufacturers have started providing small USB devices, the size of a USB thumb drive or smaller, that either have the microsim-sized smartcard pre-inserted, or that simply implement the smartcard protocol features on the internal chip. Here are a few recommendations: - - * [Nitrokey Start][5]: Open hardware and Free Software: one of the cheapest options for GnuPG use, but with fewest extra security features - - * [Nitrokey Pro][6]: Similar to the Nitrokey Start, but is tamper-resistant and offers more security features (but not U2F, see the Fido U2F section of the guide) - - * [Yubikey 4][7]: Proprietary hardware and software, but cheaper than Nitrokey Pro and comes available in the USB-C form that is more useful with newer laptops; also offers additional security features such as U2F - - - - -Our recommendation is to pick a device that is capable of both smartcard functionality and U2F, which, at the time of writing, means a Yubikey 4. - -#### Configuring your smartcard device - -Your smartcard device should Just Work (TM) the moment you plug it into any modern Linux or Mac workstation. You can verify it by running: -``` -$ gpg --card-status - -``` - -If you didn't get an error, but a full listing of the card details, then you are good to go. Unfortunately, troubleshooting all possible reasons why things may not be working for you is way beyond the scope of this guide. If you are having trouble getting the card to work with GnuPG, please seek support via your operating system's usual support channels. - -##### PINs don't have to be numbers - -Note, that despite having the name "PIN" (and implying that it must be a "number"), neither the user PIN nor the admin PIN on the card need to be numbers. - -Your device will probably have default user and admin PINs set up when it arrives. For Yubikeys, these are 123456 and 12345678, respectively. If those don't work for you, please check any accompanying documentation that came with your device. - -##### Quick setup - -To configure your smartcard, you will need to use the GnuPG menu system, as there are no convenient command-line switches: -``` -$ gpg --card-edit -[...omitted...] -gpg/card> admin -Admin commands are allowed -gpg/card> passwd - -``` - -You should set the user PIN (1), Admin PIN (3), and the Reset Code (4). Please make sure to record and store these in a safe place -- especially the Admin PIN and the Reset Code (which allows you to completely wipe the smartcard). You so rarely need to use the Admin PIN, that you will inevitably forget what it is if you do not record it. - -Getting back to the main card menu, you can also set other values (such as name, sex, login data, etc), but it's not necessary and will additionally leak information about your smartcard should you lose it. - -#### Moving the subkeys to your smartcard - -Exit the card menu (using "q") and save all changes. Next, let's move your subkeys onto the smartcard. You will need both your PGP key passphrase and the admin PIN of the card for most operations. Remember, that [fpr] stands for the full 40-character fingerprint of your key. -``` -$ gpg --edit-key [fpr] - -Secret subkeys are available. - -pub rsa4096/AAAABBBBCCCCDDDD - created: 2017-12-07 expires: 2019-12-07 usage: C - trust: ultimate validity: ultimate -ssb rsa2048/1111222233334444 - created: 2017-12-07 expires: never usage: E -ssb rsa2048/5555666677778888 - created: 2017-12-07 expires: never usage: S -[ultimate] (1). Alice Engineer -[ultimate] (2) Alice Engineer - -gpg> - -``` - -Using --edit-key puts us into the menu mode again, and you will notice that the key listing is a little different. From here on, all commands are done from inside this menu mode, as indicated by gpg>. - -First, let's select the key we'll be putting onto the card -- you do this by typing key 1 (it's the first one in the listing, our [E] subkey): -``` -gpg> key 1 - -``` - -The output should be subtly different: -``` -pub rsa4096/AAAABBBBCCCCDDDD - created: 2017-12-07 expires: 2019-12-07 usage: C - trust: ultimate validity: ultimate -ssb* rsa2048/1111222233334444 - created: 2017-12-07 expires: never usage: E -ssb rsa2048/5555666677778888 - created: 2017-12-07 expires: never usage: S -[ultimate] (1). Alice Engineer -[ultimate] (2) Alice Engineer - -``` - -Notice the * that is next to the ssb line corresponding to the key -- it indicates that the key is currently "selected." It works as a toggle, meaning that if you type key 1 again, the * will disappear and the key will not be selected any more. - -Now, let's move that key onto the smartcard: -``` -gpg> keytocard -Please select where to store the key: - (2) Encryption key -Your selection? 2 - -``` - -Since it's our [E] key, it makes sense to put it into the Encryption slot. When you submit your selection, you will be prompted first for your PGP key passphrase, and then for the admin PIN. If the command returns without an error, your key has been moved. - -**Important:** Now type key 1 again to unselect the first key, and key 2 to select the [S] key: -``` -gpg> key 1 -gpg> key 2 -gpg> keytocard -Please select where to store the key: - (1) Signature key - (3) Authentication key -Your selection? 1 - -``` - -You can use the [S] key both for Signature and Authentication, but we want to make sure it's in the Signature slot, so choose (1). Once again, if your command returns without an error, then the operation was successful. - -Finally, if you created an [A] key, you can move it to the card as well, making sure first to unselect key 2. Once you're done, choose "q": -``` -gpg> q -Save changes? (y/N) y - -``` - -Saving the changes will delete the keys you moved to the card from your home directory (but it's okay, because we have them in our backups should we need to do this again for a replacement smartcard). - -##### Verifying that the keys were moved - -If you perform --list-secret-keys now, you will see a subtle difference in the output: -``` -$ gpg --list-secret-keys -sec# rsa4096 2017-12-06 [C] [expires: 2019-12-06] - 111122223333444455556666AAAABBBBCCCCDDDD -uid [ultimate] Alice Engineer -uid [ultimate] Alice Engineer -ssb> rsa2048 2017-12-06 [E] -ssb> rsa2048 2017-12-06 [S] - -``` - -The > in the ssb> output indicates that the subkey is only available on the smartcard. If you go back into your secret keys directory and look at the contents there, you will notice that the .key files there have been replaced with stubs: -``` -$ cd ~/.gnupg/private-keys-v1.d -$ strings *.key - -``` - -The output should contain shadowed-private-key to indicate that these files are only stubs and the actual content is on the smartcard. - -#### Verifying that the smartcard is functioning - -To verify that the smartcard is working as intended, you can create a signature: -``` -$ echo "Hello world" | gpg --clearsign > /tmp/test.asc -$ gpg --verify /tmp/test.asc - -``` - -This should ask for your smartcard PIN on your first command, and then show "Good signature" after you run gpg --verify. - -Congratulations, you have successfully made it extremely difficult to steal your digital developer identity! - -### Other common GnuPG operations - -Here is a quick reference for some common operations you'll need to do with your PGP key. - -In all of the below commands, the [fpr] is your key fingerprint. - -#### Mounting your master key offline storage - -You will need your master key for any of the operations below, so you will first need to mount your backup offline storage and tell GnuPG to use it. First, find out where the media got mounted, for example, by looking at the output of the mount command. Then, locate the directory with the backup of your GnuPG directory and tell GnuPG to use that as its home: -``` -$ export GNUPGHOME=/media/disk/name/gnupg-backup -$ gpg --list-secret-keys - -``` - -You want to make sure that you see sec and not sec# in the output (the # means the key is not available and you're still using your regular home directory location). - -##### Updating your regular GnuPG working directory - -After you make any changes to your key using the offline storage, you will want to import these changes back into your regular working directory: -``` -$ gpg --export | gpg --homedir ~/.gnupg --import -$ unset GNUPGHOME - -``` - -#### Extending key expiration date - -The master key we created has the default expiration date of 2 years from the date of creation. This is done both for security reasons and to make obsolete keys eventually disappear from keyservers. - -To extend the expiration on your key by a year from current date, just run: -``` -$ gpg --quick-set-expire [fpr] 1y - -``` - -You can also use a specific date if that is easier to remember (e.g. your birthday, January 1st, or Canada Day): -``` -$ gpg --quick-set-expire [fpr] 2020-07-01 - -``` - -Remember to send the updated key back to keyservers: -``` -$ gpg --send-key [fpr] - -``` - -#### Revoking identities - -If you need to revoke an identity (e.g., you changed employers and your old email address is no longer valid), you can use a one-liner: -``` -$ gpg --quick-revoke-uid [fpr] 'Alice Engineer ' - -``` - -You can also do the same with the menu mode using gpg --edit-key [fpr]. - -Once you are done, remember to send the updated key back to keyservers: -``` -$ gpg --send-key [fpr] - -``` - -Next time, we'll look at how Git supports multiple levels of integration with PGP. - -Learn more about Linux through the free ["Introduction to Linux" ][8]course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-5-moving-subkeys-hardware-device - -作者：[KONSTANTIN RYABITSEV][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/mricon -[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools -[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key -[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys -[4]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage -[5]:https://shop.nitrokey.com/shop/product/nitrokey-start-6 -[6]:https://shop.nitrokey.com/shop/product/nitrokey-pro-3 -[7]:https://www.yubico.com/product/yubikey-4-series/ -[8]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20180321 Protecting Code Integrity with PGP - Part 6- Using PGP with Git.md b/sources/tech/20180321 Protecting Code Integrity with PGP - Part 6- Using PGP with Git.md deleted file mode 100644 index 0169d96ad6..0000000000 --- a/sources/tech/20180321 Protecting Code Integrity with PGP - Part 6- Using PGP with Git.md +++ /dev/null @@ -1,318 +0,0 @@ -Protecting Code Integrity with PGP — Part 6: Using PGP with Git -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/global-network.jpg?itok=h_hhZc36) -In this tutorial series, we're providing practical guidelines for using PGP, including basic concepts and generating and protecting your keys. If you missed the previous articles, you can catch up below. In this article, we look at Git's integration with PGP, starting with signed tags, then introducing signed commits, and finally adding support for signed pushes. - -[Part 1: Basic Concepts and Tools][1] - -[Part 2: Generating Your Master Key][2] - -[Part 3: Generating PGP Subkeys][3] - -[Part 4: Moving Your Master Key to Offline Storage][4] - -[Part 5: Moving Subkeys to a Hardware Device][5] - -One of the core features of Git is its decentralized nature -- once a repository is cloned to your system, you have full history of the project, including all of its tags, commits and branches. However, with hundreds of cloned repositories floating around, how does anyone verify that the repository you downloaded has not been tampered with by a malicious third party? You may have cloned it from GitHub or some other official-looking location, but what if someone had managed to trick you? - -Or what happens if a backdoor is discovered in one of the projects you've worked on, and the "Author" line in the commit says it was done by you, while you're pretty sure you had [nothing to do with it][6]? - -To address both of these issues, Git introduced PGP integration. Signed tags prove the repository integrity by assuring that its contents are exactly the same as on the workstation of the developer who created the tag, while signed commits make it nearly impossible for someone to impersonate you without having access to your PGP keys. - -### Checklist - - * Understand signed tags, commits, and pushes (ESSENTIAL) - - * Configure git to use your key (ESSENTIAL) - - * Learn how tag signing and verification works (ESSENTIAL) - - * Configure git to always sign annotated tags (NICE) - - * Learn how commit signing and verification works (ESSENTIAL) - - * Configure git to always sign commits (NICE) - - * Configure gpg-agent options (ESSENTIAL) - - - - -### Considerations - -Git implements multiple levels of integration with PGP, first starting with signed tags, then introducing signed commits, and finally adding support for signed pushes. - -#### Understanding Git Hashes - -Git is a complicated beast, but you need to know what a "hash" is in order to have a good grasp on how PGP integrates with it. We'll narrow it down to two kinds of hashes: tree hashes and commit hashes. - -##### Tree hashes - -Every time you commit a change to a repository, git records checksum hashes of all objects in it -- contents (blobs), directories (trees), file names and permissions, etc, for each subdirectory in the repository. It only does this for trees and blobs that have changed with each commit, so as not to re-checksum the entire tree unnecessarily if only a small part of it was touched. - -Then it calculates and stores the checksum of the toplevel tree, which will inevitably be different if any part of the repository has changed. - -##### Commit hashes - -Once the tree hash has been created, git will calculate the commit hash, which will include the following information about the repository and the change being made: - - * The checksum hash of the tree - - * The checksum hash of the tree before the change (parent) - - * Information about the author (name, email, time of authorship) - - * Information about the committer (name, email, time of commit) - - * The commit message - - - - -##### Hashing function - -At the time of writing, git still uses the SHA1 hashing mechanism to calculate checksums, though work is under way to transition to a stronger algorithm that is more resistant to collisions. Note, that git already includes collision avoidance routines, so it is believed that a successful collision attack against git remains impractical. - -#### Annotated tags and tag signatures - -Git tags allow developers to mark specific commits in the history of each git repository. Tags can be "lightweight" \-- more or less just a pointer at a specific commit, or they can be "annotated," which becomes its own object in the git tree. An annotated tag object contains all of the following information: - - * The checksum hash of the commit being tagged - - * The tag name - - * Information about the tagger (name, email, time of tagging) - - * The tag message - - - - -A PGP-signed tag is simply an annotated tag with all these entries wrapped around in a PGP signature. When a developer signs their git tag, they effectively assure you of the following: - - * Who they are (and why you should trust them) - - * What the state of their repository was at the time of signing: - - * The tag includes the hash of the commit - - * The commit hash includes the hash of the toplevel tree - - * Which includes hashes of all files, contents, and subtrees - * It also includes all information about authorship - - * Including exact times when changes were made - - - - -When you clone a git repository and verify a signed tag, that gives you cryptographic assurance that all contents in the repository, including all of its history, are exactly the same as the contents of the repository on the developer's computer at the time of signing. - -#### Signed commits - -Signed commits are very similar to signed tags -- the contents of the commit object are PGP-signed instead of the contents of the tag object. A commit signature also gives you full verifiable information about the state of the developer's tree at the time the signature was made. Tag signatures and commit PGP signatures provide exact same security assurances about the repository and its entire history. - -#### Signed pushes - -This is included here for completeness' sake, since this functionality needs to be enabled on the server receiving the push before it does anything useful. As we saw above, PGP-signing a git object gives verifiable information about the developer's git tree, but not about their intent for that tree. - -For example, you can be working on an experimental branch in your own git fork trying out a promising cool feature, but after you submit your work for review, someone finds a nasty bug in your code. Since your commits are properly signed, someone can take the branch containing your nasty bug and push it into master, introducing a vulnerability that was never intended to go into production. Since the commit is properly signed with your key, everything looks legitimate and your reputation is questioned when the bug is discovered. - -Ability to require PGP-signatures during git push was added in order to certify the intent of the commit, and not merely verify its contents. - -#### Configure git to use your PGP key - -If you only have one secret key in your keyring, then you don't really need to do anything extra, as it becomes your default key. - -However, if you happen to have multiple secret keys, you can tell git which key should be used ([fpr] is the fingerprint of your key): -``` -$ git config --global user.signingKey [fpr] - -``` - -NOTE: If you have a distinct gpg2 command, then you should tell git to always use it instead of the legacy gpg from version 1: -``` -$ git config --global gpg.program gpg2 - -``` - -#### How to work with signed tags - -To create a signed tag, simply pass the -s switch to the tag command: -``` -$ git tag -s [tagname] - -``` - -Our recommendation is to always sign git tags, as this allows other developers to ensure that the git repository they are working with has not been maliciously altered (e.g. in order to introduce backdoors). - -##### How to verify signed tags - -To verify a signed tag, simply use the verify-tag command: -``` -$ git verify-tag [tagname] - -``` - -If you are verifying someone else's git tag, then you will need to import their PGP key. Please refer to the "Trusted Team communication" document in the same repository for guidance on this topic. - -##### Verifying at pull time - -If you are pulling a tag from another fork of the project repository, git should automatically verify the signature at the tip you're pulling and show you the results during the merge operation: -``` -$ git pull [url] tags/sometag - -``` - -The merge message will contain something like this: -``` -Merge tag 'sometag' of [url] - -[Tag message] - -# gpg: Signature made [...] -# gpg: Good signature from [...] - -``` - -#### Configure git to always sign annotated tags - -Chances are, if you're creating an annotated tag, you'll want to sign it. To force git to always sign annotated tags, you can set a global configuration option: -``` -$ git config --global tag.forceSignAnnotated true - -``` - -Alternatively, you can just train your muscle memory to always pass the -s switch: -``` -$ git tag -asm "Tag message" tagname - -``` - -#### How to work with signed commits - -It is easy to create signed commits, but it is much more difficult to incorporate them into your workflow. Many projects use signed commits as a sort of "Committed-by:" line equivalent that records code provenance -- the signatures are rarely verified by others except when tracking down project history. In a sense, signed commits are used for "tamper evidence," and not to "tamper-proof" the git workflow. - -To create a signed commit, you just need to pass the -S flag to the git commit command (it's capital -S due to collision with another flag): -``` -$ git commit -S - -``` - -Our recommendation is to always sign commits and to require them of all project members, regardless of whether anyone is verifying them (that can always come at a later time). - -##### How to verify signed commits - -To verify a single commit you can use verify-commit: -``` -$ git verify-commit [hash] - -``` - -You can also look at repository logs and request that all commit signatures are verified and shown: -``` -$ git log --pretty=short --show-signature - -``` - -##### Verifying commits during git merge - -If all members of your project sign their commits, you can enforce signature checking at merge time (and then sign the resulting merge commit itself using the -S flag): -``` -$ git merge --verify-signatures -S merged-branch - -``` - -Note, that the merge will fail if there is even one commit that is not signed or does not pass verification. As it is often the case, technology is the easy part -- the human side of the equation is what makes adopting strict commit signing for your project difficult. - -##### If your project uses mailing lists for patch management - -If your project uses a mailing list for submitting and processing patches, then there is little use in signing commits, because all signature information will be lost when sent through that medium. It is still useful to sign your commits, just so others can refer to your publicly hosted git trees for reference, but the upstream project receiving your patches will not be able to verify them directly with git. - -You can still sign the emails containing the patches, though. - -#### Configure git to always sign commits - -You can tell git to always sign commits: -``` -git config --global commit.gpgSign true - -``` - -Or you can train your muscle memory to always pass the -S flag to all git commit operations (this includes --amend). - -#### Configure gpg-agent options - -The GnuPG agent is a helper tool that will start automatically whenever you use the gpg command and run in the background with the purpose of caching the private key passphrase. This way you only have to unlock your key once to use it repeatedly (very handy if you need to sign a bunch of git operations in an automated script without having to continuously retype your passphrase). - -There are two options you should know in order to tweak when the passphrase should be expired from cache: - - * default-cache-ttl (seconds): If you use the same key again before the time-to-live expires, the countdown will reset for another period. The default is 600 (10 minutes). - - * max-cache-ttl (seconds): Regardless of how recently you've used the key since initial passphrase entry, if the maximum time-to-live countdown expires, you'll have to enter the passphrase again. The default is 30 minutes. - - - - -If you find either of these defaults too short (or too long), you can edit your ~/.gnupg/gpg-agent.conf file to set your own values: -``` -# set to 30 minutes for regular ttl, and 2 hours for max ttl -default-cache-ttl 1800 -max-cache-ttl 7200 - -``` - -##### Bonus: Using gpg-agent with ssh - -If you've created an [A] (Authentication) key and moved it to the smartcard, you can use it with ssh for adding 2-factor authentication for your ssh sessions. You just need to tell your environment to use the correct socket file for talking to the agent. - -First, add the following to your ~/.gnupg/gpg-agent.conf: -``` -enable-ssh-support - -``` - -Then, add this to your .bashrc: -``` -export SSH_AUTH_SOCK=$(gpgconf --list-dirs agent-ssh-socket) - -``` - -You will need to kill the existing gpg-agent process and start a new login session for the changes to take effect: -``` -$ killall gpg-agent -$ bash -$ ssh-add -L - -``` - -The last command should list the SSH representation of your PGP Auth key (the comment should say cardno:XXXXXXXX at the end to indicate it's coming from the smartcard). - -To enable key-based logins with ssh, just add the ssh-add -L output to ~/.ssh/authorized_keys on remote systems you log in to. Congratulations, you've just made your ssh credentials extremely difficult to steal. - -As a bonus, you can get other people's PGP-based ssh keys from public keyservers, should you need to grant them ssh access to anything: -``` -$ gpg --export-ssh-key [keyid] - -``` - -This can come in super handy if you need to allow developers access to git repositories over ssh. Next time, we'll provide tips for protecting your email accounts as well as your PGP keys. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-6-using-pgp-git - -作者：[KONSTANTIN RYABITSEV][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/mricon -[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools -[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key -[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys -[4]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage -[5]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-5-moving-subkeys-hardware-device -[6]:https://github.com/jayphelps/git-blame-someone-else diff --git a/sources/tech/20180326 Manage your workstation with Ansible- Automating configuration.md b/sources/tech/20180326 Manage your workstation with Ansible- Automating configuration.md deleted file mode 100644 index 21821a070c..0000000000 --- a/sources/tech/20180326 Manage your workstation with Ansible- Automating configuration.md +++ /dev/null @@ -1,236 +0,0 @@ -Manage your workstation with Ansible: Automating configuration -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/robot_arm_artificial_ai.png?itok=8CUU3U_7) -Ansible is an amazing automation and configuration management tool. It is mainly used for servers and cloud deployments, and it gets far less attention for its use in workstations, both desktops and laptops, which is the focus of this series. - -In the [first part][1] of this series, I showed you basic usage of the `ansible-pull` command, and we created a playbook that installs a handful of packages. That wasn't extremely useful by itself, but it set the stage for further automation. - -In this article, everything comes together full circle, and by the end we will have a fully working solution for automating workstation configuration. This time, we'll set up our Ansible configuration such that future changes we make will automatically be applied to our workstations. At this point, I'm assuming you already worked through part one. If you haven't, feel free to do that now and then return to this article when you're done. You should already have a GitHub repository with the code from the first article inside it. We're going to build directly on what we did before. - -First, we need to do some reorganization because we're going to do more than just install packages. At this point, we currently have a playbook named `local.yml` with the following content: -``` -- hosts: localhost - -  become: true - -  tasks: - -  - name: Install packages - -    apt: name={{item}} - -    with_items: - -      - htop - -      - mc - -      - tmux - -``` - -That's all well and good if we only want to perform one task. As we add new things to our configuration, this file will become quite large and get very cluttered. It's better to organize our plays into individual files with each responsible for a different type of configuration. To achieve this, create what's called a taskbook, which is very much like a playbook but the contents are more streamlined. Let's create a directory for our taskbooks inside our Git repository: -``` -mkdir tasks - -``` - -The code inside our current `local.yml` playbook lends itself well to become a taskbook for installing packages. Let's move this file into the `tasks` directory we just created with a new name: -``` -mv local.yml tasks/packages.yml - -``` - -Now, we can edit our `packages.yml` taskbook and strip it down quite a bit. In fact, we can strip everything except for the individual task itself. Let's make `packages.yml` look like this: -``` -- name: Install packages - -  apt: name={{item}} - -  with_items: - -    - htop - -    - mc - -    - tmux - -``` - -As you can see, it uses the same syntax, but we stripped out everything that isn't necessary to the task it's performing. Now we have a dedicated taskbook for installing packages. However, we still need a file named `local.yml`, since `ansible-pull` still expects to find a file with that name. So we'll create a fresh one with this content in the root of our repository (not in the `tasks` directory): -``` -- hosts: localhost - -  become: true - -  pre_tasks: - -    - name: update repositories - -      apt: update_cache=yes - -      changed_when: False - - - -  tasks: - -    - include: tasks/packages.yml - -``` - -This new `local.yml` acts as an index that will import all our taskbooks. I've added a few new things to this file that you haven't seen yet in this series. First, at the beginning of the file, I added `pre_tasks`, which allows us to have Ansible perform a task before all the other tasks run. In this case, we're telling Ansible to update our distribution's repository index. This line does that for us: -``` -apt: update_cache=yes - -``` - -Normally the `apt` module allows us to install packages, but we can also tell it to update our repository index. The idea is that we want all our individual plays to work with a fresh index each time Ansible runs. This will help ensure we don't have an issue with a stale index while attempting to install a package. Note that the `apt` module works only with Debian, Ubuntu, and their derivatives. If you're running a different distribution, you'll want to use a module specific to your distribution rather than `apt`. See the documentation for Ansible if you need to use a different module. - -The following line is also worth further explanation: -``` -changed_when: False - -``` - -This line on an individual task stops Ansible from reporting the results of the play as changed even when it results in a change in the system. In this case, we don't care if the repository index contains new data; it almost always will, since repositories are always changing. We don't care about changes to `apt` repositories, as index changes are par for the course. If we omit this line, we'll see the summary at the end of the process report that something has changed, even if it was merely about the repository being updated. It's better to ignore these types of changes. - -Next is our normal tasks section, and we import the taskbook we created. Each time we add another taskbook, we add another line here: -``` -tasks: - -  - include: tasks/packages.yml - -``` - -If you were to run the `ansible-pull` command here, it should essentially do the same thing as it did in the last article. The difference is that we have improved our organization and we can more efficiently expand on it. The `ansible-pull` command syntax, to save you from finding the previous article, is this: -``` -sudo ansible-pull -U https://github.com//ansible.git - -``` - -If you recall, the `ansible-pull` command pulls down a Git repository and applies the configuration it contains. - -Now that our foundation is in place, we can expand upon our Ansible config and add features. Specifically, we'll add configuration to automate the deployment of future changes to our workstations. To support this goal, the first thing we should do is to create a user specifically to apply our Ansible configuration. This isn't required—we can continue to run our Ansible configuration under our own user. But using a separate user segregates this to a system process that will run in the background, without our involvement. - -We could create this user with the normal method, but since we're using Ansible, we should shy away from manual changes. Instead, we'll create a taskbook to handle user creation. This taskbook will create just one user for now, but you can always add additional plays to this taskbook to add additional users. I'll call this user `ansible`, but you can name it something else if you wish (if you do, make sure to update all occurrences). Let's create a taskbook named `users.yml` and place this code inside of it: -``` -- name: create ansible user - -  user: name=ansible uid=900 - -``` - -Next, we need to edit our `local.yml` file and append this new taskbook to the file, so it will look like this: -``` -- hosts: localhost - -  become: true - -  pre_tasks: - -    - name: update repositories - -      apt: update_cache=yes - -      changed_when: False - - - -  tasks: - -    - include: tasks/users.yml - -    - include: tasks/packages.yml - -``` - -Now when we run our `ansible-pull` command, a user named `ansible` will be created on the system. Note that I specifically declared `User ID 900` for this user by using the `UID` option. This isn't required, but it's recommended. The reason is that UIDs under 1,000 are typically not shown on the login screen, which is great because there's no reason we would need to log into a desktop session as our `ansible` user. UID 900 is arbitrary; it should be any number under 1,000 that's not already in use. You can find out if UID 900 is in use on your system with the following command: -``` -cat /etc/passwd |grep 900 - -``` - -However, you shouldn't run into a problem with this UID because I've never seen it used by default in any distribution I've used so far. - -Now, we have an `ansible` user that will later be used to apply our Ansible configuration automatically. Next, we can create the actual cron job that will be used to automate this. Rather than place this in the `users.yml` taskbook we just created, we should separate this into its own file. Create a taskbook named `cron.yml` in the tasks directory and place the following code inside: -``` -- name: install cron job (ansible-pull) - -  cron: user="ansible" name="ansible provision" minute="*/10" job="/usr/bin/ansible-pull -o -U https://github.com//ansible.git > /dev/null" - -``` - -The syntax for the cron module should be fairly self-explanatory. With this play, we're creating a cron job to be run as the `ansible` user. The job will execute every 10 minutes, and the command it will execute is this: -``` -/usr/bin/ansible-pull -o -U https://github.com//ansible.git > /dev/null - -``` - -Also, we can put additional cron jobs we want all our workstations to have into this one file. We just need to add additional plays to add new cron jobs. However, simply adding a new taskbook for cron isn't enough—we'll also need to add it to our `local.yml` file so it will be called. Place the following line with the other includes: -``` -- include: tasks/cron.yml - -``` - -Now when `ansible-pull` is run, it will set up a new cron job that will be run as the `ansible` user every 10 minutes. But, having an Ansible job running every 10 minutes isn't ideal because it will take considerable CPU power. It really doesn't make sense for Ansible to run every 10 minutes unless we've changed something in the Git repository. - -However, we've already solved this problem. Notice the `-o` option I added to the `ansible-pull` command in the cron job that we've never used before. This option tells Ansible to run only if the repository has changed since the last time `ansible-pull` was called. If the repository hasn't changed, it won't do anything. This way, you're not wasting valuable CPU for no reason. Sure, some CPU will be used when it pulls down the repository, but not nearly as much as it would use if it were applying your entire configuration all over again. When `ansible-pull` does run, it will go through all the tasks in the Playbook and taskbooks, but at least it won't run for no purpose. - -Although we've added all the required components to automate `ansible-pull`, it actually won't work properly yet. The `ansible-pull` command will run with `sudo`, which would give it access to perform system-level commands. However, our `ansible` user is not set up to perform tasks as `sudo`. Therefore, when the cron job triggers, it will fail. Normally we could just use `visudo` and manually set the `ansible` user up to have this access. However, we should do things the Ansible way from now on, and this is a great opportunity to show you how the `copy` module works. The `copy` module allows you to copy a file from your Ansible repository to somewhere else in the filesystem. In our case, we'll copy a config file for `sudo` to `/etc/sudoers.d/` so that the `ansible` user can perform administrative tasks. - -Open up the `users.yml` taskbook, and add the following play to the bottom: -``` -- name: copy sudoers_ansible - -  copy: src=files/sudoers_ansible dest=/etc/sudoers.d/ansible owner=root group=root mode=0440 - -``` - -The `copy` module, as we can see, copies a file from our repository to somewhere else. In this case, we're grabbing a file named `sudoers_ansible` (which we will create shortly) and copying it to `/etc/sudoers.d/ansible` with `root` as the owner. - -Next, we need to create the file that we'll be copying. In the root of your Ansible repository, create a `files` directory:​ -``` -mkdir files - -``` - -Then, in the `files` directory we just created, create the `sudoers_ansible` file with the following content: -``` -ansible ALL=(ALL) NOPASSWD: ALL - -``` - -Creating a file in `/etc/sudoers.d`, like we're doing here, allows us to configure `sudo` for a specific user. Here we're allowing the `ansible` user full access to the system via `sudo` without a password prompt. This will allow `ansible-pull` to run as a background task without us needing to run it manually. - -Now, you can run `ansible-pull` again to pull down the latest changes: -``` -sudo ansible-pull -U https://github.com//ansible.git - -``` - -From this point forward, the cron job for `ansible-pull` will run every 10 minutes in the background and check your repository for changes. If it finds changes, it will run your playbook and apply your taskbooks. - -So now we have a fully working solution. When you first set up a new laptop or desktop, you'll run the `ansible-pull` command manually, but only the first time. From that point forward, the `ansible` user will take care of subsequent runs in the background. When you want to make a change to your workstation machines, you simply pull down your Git repository, make the changes, then push those changes back to the repository. Then, the next time the cron job fires on each machine, it will pull down those changes and apply them. You now only have to make changes once, and all your workstations will follow suit. This method may be a bit unconventional though. Normally, you'd have an `inventory` file with your machines listed and several roles each machine could be a member of. However, the `ansible-pull` method, as described in this article, is a very efficient way of managing workstation configuration. - -I have updated the code in my [GitHub repository][2] for this article, so feel free to browse the code there and check your syntax against mine. Also, I moved the code from the previous article into its own directory in that repository. - -In part 3, we'll close out the series by using Ansible to configure GNOME desktop settings. I'll show you how to set your wallpaper and lock screen, apply a desktop theme, and more. - -In the meantime, it's time for a little homework assignment. Most of us have configuration files we like to maintain for various applications we use. This could be configuration files for Bash, Vim, or whatever tools you use. I challenge you now to automate copying these configuration files to your machines via the Ansible repository we've been working on. In this article, I've shown you how to copy a file, so take a look at that and see if you can apply that knowledge to your personal files. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/3/manage-your-workstation-configuration-ansible-part-2 - -作者：[Jay LaCroix][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) -选题：[lujun9972](https://github.com/lujun9972) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/jlacroix -[1]:https://opensource.com/article/18/3/manage-workstation-ansible -[2]:https://github.com/jlacroix82/ansible_article.git diff --git a/sources/tech/20180327 Protecting Code Integrity with PGP - Part 7- Protecting Online Accounts.md b/sources/tech/20180327 Protecting Code Integrity with PGP - Part 7- Protecting Online Accounts.md deleted file mode 100644 index 8ebb9af3f6..0000000000 --- a/sources/tech/20180327 Protecting Code Integrity with PGP - Part 7- Protecting Online Accounts.md +++ /dev/null @@ -1,146 +0,0 @@ -Protecting Code Integrity with PGP — Part 7: Protecting Online Accounts -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/online-pgp.jpg?itok=BWc_Bk6q) -So far in this tutorial series, we've provided practical guidelines for using PGP, including basic concepts and steps for generating and protecting your keys. If you missed the previous articles, you can catch up below. In this final article, we offer additional guidance for protecting your online accounts, which is of paramount importance today. - -[Part 1: Basic Concepts and Tools][1] - -[Part 2: Generating Your Master Key][2] - -[Part 3: Generating PGP Subkeys][3] - -[Part 4: Moving Your Master Key to Offline Storage][4] - -[Part 5: Moving Subkeys to a Hardware Device][5] - -[Part 6: Using PGP with Git][6] - -### Checklist - - * Get a U2F-capable device (ESSENTIAL) - - * Enable 2-factor authentication for your online accounts (ESSENTIAL) - - * GitHub/GitLab - - * Google - - * Social media - - * Use U2F as primary mechanism, with TOTP as fallback (ESSENTIAL) - - - - -#### Considerations - -You may have noticed how a lot of your online developer identity is tied to your email address. If someone can gain access to your mailbox, they would be able to do a lot of damage to you personally, and to your reputation as a free software developer. Protecting your email accounts is just as important as protecting your PGP keys. - -##### Two-factor authentication with Fido U2F - -[Two-factor authentication][7] is a mechanism to improve account security by requiring a physical token in addition to a username and password. The goal is to make sure that even if someone steals your password (via keylogging, shoulder surfing, or other means), they still wouldn't be able to gain access to your account without having in their possession a specific physical device ("something you have" factor). - -The most widely known mechanisms for 2-factor authentication are: - - * SMS-based verification - - * Time-based One-Time Passwords (TOTP) via a smartphone app, such as the "Google Authenticator" or similar solutions - - * Hardware tokens supporting Fido U2F - - - - -SMS-based verification is easiest to configure, but has the following important downsides: it is useless in areas without signal (e.g. most building basements), and can be defeated if the attacker is able to intercept or divert SMS messages, for example by cloning your SIM card. - -TOTP-based multi-factor authentication offers more protection than SMS, but has important scaling downsides (there are only so many tokens you can add to your smartphone app before finding the correct one becomes unwieldy). Plus, there's no avoiding the fact that your secret key ends up stored on the smartphone itself -- which is a complex, globally connected device that may or may not have been receiving timely security patches from the manufacturer. - -Most importantly, neither TOTP nor SMS methods protect you from phishing attacks -- if the phisher is able to steal both your account password and the 2-factor token, they can replay them on the legitimate site and gain access to your account. - -[Fido U2F][8] is a standard developed specifically to provide a mechanism for 2-factor authentication and to combat credential phishing. The U2F protocol will store each site's unique key on the USB token and will prevent you from accidentally giving the attacker both your password and your one-time token if you try to use it on anything other than the legitimate website. - -Both Chrome and Firefox support U2F 2-factor authentication, and hopefully other browsers will soon follow. - -##### Get a token capable of Fido U2F - -There are [many options available][9] for hardware tokens with Fido U2F support, but if you're already ordering a smartcard-capable physical device, then your best option is a Yubikey 4, which supports both. - -##### Enable 2-factor authentication on your online accounts - -You definitely want to enable this option on the email provider you are using (especially if it is Google, which has excellent support for U2F). Other sites where this functionality should be enabled are: - - * GitHub: it probably occurred to you when you uploaded your PGP public key that if anyone else is able to gain access to your account, they can replace your key with their own. If you publish code on GitHub, you should take care of your account security by protecting it with U2F-backed authentication. - - * GitLab: for the same reasons as above. - - * Google: if you have a google account, you will be surprised how many sites allow logging in with Google authentication instead of site-specific credentials. - - * Facebook: same as above, a lot of online sites offer the option to authenticate using a Facebook account. You should 2-factor protect your Facebook account even if you do not use it. - - * Other sites, as you deem necessary. See [dongleauth.info][10] for inspiration. - - - - -##### Configure TOTP failover, if possible - -Many sites will allow you to configure multiple 2-factor mechanisms, and the recommended setup is: - - * U2F token as the primary mechanism - - * TOTP phone app as the secondary mechanism - - - - -This way, even if you lose your U2F token, you should be able to re-gain access to your account. Alternatively, you can enroll multiple U2F tokens (e.g. you can get another cheap token that only does U2F and use it for backup reasons). - -### Further reading - -By this point you have accomplished the following important tasks: - - 1. Created your developer identity and protected it using PGP cryptography. - - 2. Configured your environment so your identity is not easily stolen by moving your master key offline and your subkeys to an external hardware device. - - 3. Configured your git environment to ensure that anyone using your project is able to verify the integrity of the repository and its entire history. - - 4. Secured your online accounts using 2-factor authentication. - - - - -You are already in a good place, but you should also read up on the following topics: - - * How to secure your team communication (see the document in this repository). Decisions regarding your project development and governance require just as much careful protection as any committed code, if not so. Make sure that your team communication is trusted and the integrity of all decisions is verified. - - * How to secure your workstation (see the document in this repository). Your goal is to minimize risky behaviour that would cause your project code to be contaminated, or your developer identity to be stolen. - - * How to write secure code (see various documentation related to the programming languages and libraries used by your project). Bad, insecure code is still bad, insecure code even if there is a PGP signature on the commit that introduced it. - - - - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-7-protecting-online-accounts - -作者：[Konstantin Ryabitsev][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) -选题：[lujun9972](https://github.com/lujun9972) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/mricon -[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools -[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key -[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys -[4]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage -[5]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-5-moving-subkeys-hardware-device -[6]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-6-using-pgp-git -[7]:https://en.wikipedia.org/wiki/Multi-factor_authentication -[8]:https://en.wikipedia.org/wiki/Universal_2nd_Factor -[9]:http://www.dongleauth.info/dongles/ -[10]:http://www.dongleauth.info/ diff --git a/sources/tech/20180402 An introduction to the Flask Python web app framework.md b/sources/tech/20180402 An introduction to the Flask Python web app framework.md new file mode 100644 index 0000000000..4b07338bc5 --- /dev/null +++ b/sources/tech/20180402 An introduction to the Flask Python web app framework.md @@ -0,0 +1,451 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (An introduction to the Flask Python web app framework) +[#]: via: (https://opensource.com/article/18/4/flask) +[#]: author: (Nicholas Hunt-Walker https://opensource.com/users/nhuntwalker) +[#]: url: ( ) + +An introduction to the Flask Python web app framework +====== +In the first part in a series comparing Python frameworks, learn about Flask. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/python-programming-code-keyboard.png?itok=fxiSpmnd) + +If you're developing a web app in Python, chances are you're leveraging a framework. A [framework][1] "is a code library that makes a developer's life easier when building reliable, scalable, and maintainable web applications" by providing reusable code or extensions for common operations. There are a number of frameworks for Python, including [Flask][2], [Tornado][3], [Pyramid][4], and [Django][5]. New Python developers often ask: Which framework should I use? + + * New visitors to the site should be able to register new accounts. + * Registered users can log in, log out, see information for their profiles, and edit their information. + * Registered users can create new task items, see their existing tasks, and edit existing tasks. + + + +This series is designed to help developers answer that question by comparing those four frameworks. To compare their features and operations, I'll take each one through the process of constructing an API for a simple To-Do List web application. The API is itself fairly straightforward: + +All this rounds out to a compact set of API endpoints that each backend must implement, along with the allowed HTTP methods: + + * `GET /` + * `POST /accounts` + * `POST /accounts/login` + * `GET /accounts/logout` + * `GET, PUT, DELETE /accounts/` + * `GET, POST /accounts//tasks` + * `GET, PUT, DELETE /accounts//tasks/` + + + +Each framework has a different way to put together its routes, models, views, database interaction, and overall application configuration. I'll describe those aspects of each framework in this series, which will begin with Flask. + +### Flask startup and configuration + +Like most widely used Python libraries, the Flask package is installable from the [Python Package Index][6] (PPI). First create a directory to work in (something like `flask_todo` is a fine directory name) then install the `flask` package. You'll also want to install `flask-sqlalchemy` so your Flask application has a simple way to talk to a SQL database. + +I like to do this type of work within a Python 3 virtual environment. To get there, enter the following on the command line: + +``` +$ mkdir flask_todo +$ cd flask_todo +$ pipenv install --python 3.6 +$ pipenv shell +(flask-someHash) $ pipenv install flask flask-sqlalchemy +``` + +If you want to turn this into a Git repository, this is a good place to run `git init`. It'll be the root of the project, and if you want to export the codebase to a different machine, it will help to have all the necessary setup files here. + +A good way to get moving is to turn the codebase into an installable Python distribution. At the project's root, create `setup.py` and a directory called `todo` to hold the source code. + +The `setup.py` should look something like this: + +``` +from setuptools import setup, find_packages + +requires = [ +    'flask', +    'flask-sqlalchemy', +    'psycopg2', +] + +setup( +    name='flask_todo', +    version='0.0', +    description='A To-Do List built with Flask', +    author='', +    author_email='', +    keywords='web flask', +    packages=find_packages(), +    include_package_data=True, +    install_requires=requires +) +``` + +This way, whenever you want to install or deploy your project, you'll have all the necessary packages in the `requires` list. You'll also have everything you need to set up and install the package in `site-packages`. For more information on how to write an installable Python distribution, check out [the docs on setup.py][7]. + +Within the `todo` directory containing your source code, create an `app.py` file and a blank `__init__.py` file. The `__init__.py` file allows you to import from `todo` as if it were an installed package. The `app.py` file will be the application's root. This is where all the `Flask` application goodness will go, and you'll create an environment variable that points to that file. If you're using `pipenv` (like I am), you can locate your virtual environment with `pipenv --venv` and set up that environment variable in your environment's `activate` script. + +``` +# in your activate script, probably at the bottom (but anywhere will do) + +export FLASK_APP=$VIRTUAL_ENV/../todo/app.py +export DEBUG='True' +``` + +When you installed `Flask`, you also installed the `flask` command-line script. Typing `flask run` will prompt the virtual environment's Flask package to run an HTTP server using the `app` object in whatever script the `FLASK_APP` environment variable points to. The script above also includes an environment variable named `DEBUG` that will be used a bit later. + +Let's talk about this `app` object. + +In `todo/app.py`, you'll create an `app` object, which is an instance of the `Flask` object. It'll act as the central configuration object for the entire application. It's used to set up pieces of the application required for extended functionality, e.g., a database connection and help with authentication. + +It's regularly used to set up the routes that will become the application's points of interaction. To explain what this means, let's look at the code it corresponds to. + +``` +from flask import Flask + +app = Flask(__name__) + +@app.route('/') +def hello_world(): +    """Print 'Hello, world!' as the response body.""" +    return 'Hello, world!' +``` + +This is the most basic complete Flask application. `app` is an instance of `Flask`, taking in the `__name__` of the script file. This lets Python know how to import from files relative to this one. The `app.route` decorator decorates the first **view** function; it can specify one of the routes used to access the application. (We'll look at this later.) + +Any view you specify must be decorated by `app.route` to be a functional part of the application. You can have as many functions as you want scattered across the application, but in order for that functionality to be accessible from anything external to the application, you must decorate that function and specify a route to make it into a view. + +In the example above, when the app is running and accessed at `http://domainname/`, a user will receive `"Hello, World!"` as a response. + +### Connecting the database in Flask + +While the code example above represents a complete Flask application, it doesn't do anything interesting. One interesting thing a web application can do is persist user data, but it needs the help of and connection to a database. + +Flask is very much a "do it yourself" web framework. This means there's no built-in database interaction, but the `flask-sqlalchemy` package will connect a SQL database to a Flask application. The `flask-sqlalchemy` package needs just one thing to connect to a SQL database: The database URL. + +Note that a wide variety of SQL database management systems can be used with `flask-sqlalchemy`, as long as the DBMS has an intermediary that follows the [DBAPI-2 standard][8]. In this example, I'll use PostgreSQL (mainly because I've used it a lot), so the intermediary to talk to the Postgres database is the `psycopg2` package. Make sure `psycopg2` is installed in your environment and include it in the list of required packages in `setup.py`. You don't have to do anything else with it; `flask-sqlalchemy` will recognize Postgres from the database URL. + +Flask needs the database URL to be part of its central configuration through the `SQLALCHEMY_DATABASE_URI` attribute. A quick and dirty solution is to hardcode a database URL into the application. + +``` +# top of app.py +from flask import Flask +from flask_sqlalchemy import SQLAlchemy + +app = Flask(__name__) +app.config['SQLALCHEMY_DATABASE_URI'] = 'postgres://localhost:5432/flask_todo' +db = SQLAlchemy(app) +``` + +However, this is not a sustainable solution. If you change databases or don't want your database URL visible in source control, you'll have to take extra steps to ensure your information is appropriate for the environment. + +You can make things simpler by using environment variables. They will ensure that, no matter what machine the code runs on, it always points at the right stuff if that stuff is configured in the running environment. It also ensures that, even though you need that information to run the application, it never shows up as a hardcoded value in source control. + +In the same place you declared `FLASK_APP`, declare a `DATABASE_URL` pointing to the location of your Postgres database. Development tends to work locally, so just point to your local database. + +``` +# also in your activate script + +export DATABASE_URL='postgres://localhost:5432/flask_todo' +``` + +Now in `app.py`, include the database URL in your app configuration. + +``` +app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('DATABASE_URL', '') +db = SQLAlchemy(app) +``` + +And just like that, your application has a database connection! + +### Defining objects in Flask + +Having a database to talk to is a good first step. Now it's time to define some objects to fill that database. + +In application development, a "model" refers to the data representation of some real or conceptual object. For example, if you're building an application for a car dealership, you may define a `Car` model that encapsulates all of a car's attributes and behavior. + +In this case, you're building a To-Do List with Tasks, and each Task belongs to a User. Before you think too deeply about how they're related to each other, start by defining objects for Tasks and Users. + +The `flask-sqlalchemy` package leverages [SQLAlchemy][9] to set up and inform the database structure. You'll define a model that will live in the database by inheriting from the `db.Model` object and define the attributes of those models as `db.Column` instances. For each column, you must specify a data type, so you'll pass that data type into the call to `db.Column` as the first argument. + +Because the model definition occupies a different conceptual space than the application configuration, make `models.py` to hold model definitions separate from `app.py`. The Task model should be constructed to have the following attributes: + + * `id`: a value that's a unique identifier to pull from the database + * `name`: the name or title of the task that the user will see when the task is listed + * `note`: any extra comments that a person might want to leave with their task + * `creation_date`: the date and time the task was created + * `due_date`: the date and time the task is due to be completed (if at all) + * `completed`: a way to indicate whether or not the task has been completed + + + +Given this attribute list for Task objects, the application's `Task` object can be defined like so: + +``` +from .app import db +from datetime import datetime + +class Task(db.Model): +    """Tasks for the To Do list.""" +    id = db.Column(db.Integer, primary_key=True) +    name = db.Column(db.Unicode, nullable=False) +    note = db.Column(db.Unicode) +    creation_date = db.Column(db.DateTime, nullable=False) +    due_date = db.Column(db.DateTime) +    completed = db.Column(db.Boolean, default=False) + +    def __init__(self, *args, **kwargs): +        """On construction, set date of creation.""" +        super().__init__(*args, **kwargs) +        self.creation_date = datetime.now() +``` + +Note the extension of the class constructor method. At the end of the day, any model you construct is still a Python object and therefore must go through construction in order to be instantiated. It's important to ensure that the creation date of the model instance reflects its actual date of creation. You can explicitly set that relationship by effectively saying, "when an instance of this model is constructed, record the date and time and set it as the creation date." + +### Model relationships + +In a given web application, you may want to be able to express relationships between objects. In the To-Do List example, users own multiple tasks, and each task is owned by only one user. This is an example of a "many-to-one" relationship, also known as a foreign key relationship, where the tasks are the "many" and the user owning those tasks is the "one." + +In Flask, a many-to-one relationship can be specified using the `db.relationship` function. First, build the User object. + +``` +class User(db.Model): +    """The User object that owns tasks.""" +    id = db.Column(db.Integer, primary_key=True) +    username = db.Column(db.Unicode, nullable=False) +    email = db.Column(db.Unicode, nullable=False) +    password = db.Column(db.Unicode, nullable=False) +    date_joined = db.Column(db.DateTime, nullable=False) +    token = db.Column(db.Unicode, nullable=False) + +    def __init__(self, *args, **kwargs): +        """On construction, set date of creation.""" +        super().__init__(*args, **kwargs) +        self.date_joined = datetime.now() +        self.token = secrets.token_urlsafe(64) +``` + +It looks very similar to the Task object; you'll find that most objects have the same basic format of class attributes as table columns. Every once in a while, you'll run into something a little different, including some multiple-inheritance magic, but this is the norm. + +Now that the `User` model is created, you can set up the foreign key relationship. For the "many," set fields for the `user_id` of the `User` that owns this task, as well as the `user` object with that ID. Also make sure to include a keyword argument (`back_populates`) that updates the User model when the task gets a user as an owner. + +For the "one," set a field for the `tasks` the specific user owns. Similar to maintaining the two-way relationship on the Task object, set a keyword argument on the User's relationship field to update the Task when it is assigned to a user. + +``` +# on the Task object +user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False) +user = db.relationship("user", back_populates="tasks") + +# on the User object +tasks = db.relationship("Task", back_populates="user") +``` + +### Initializing the database + +Now that the models and model relationships are set, start setting up your database. Flask doesn't come with its own database-management utility, so you'll have to write your own (to some degree). You don't have to get fancy with it; you just need something to recognize what tables are to be created and some code to create them (or drop them should the need arise). If you need something more complex, like handling updates to database tables (i.e., database migrations), you'll want to look into a tool like [Flask-Migrate][10] or [Flask-Alembic][11]. + +Create a script called `initializedb.py` next to `setup.py` for managing the database. (Of course, it doesn't need to be called this, but why not give names that are appropriate to a file's function?) Within `initializedb.py`, import the `db` object from `app.py` and use it to create or drop tables. `initializedb.py` should end up looking something like this: + +``` +from todo.app import db +import os + +if bool(os.environ.get('DEBUG', '')): +    db.drop_all() +db.create_all() +``` + +If a `DEBUG` environment variable is set, drop tables and rebuild. Otherwise, just create the tables once and you're good to go. + +### Views and URL config + +The last bits needed to connect the entire application are the views and routes. In web development, a "view" (in concept) is functionality that runs when a specific access point (a "route") in your application is hit. These access points appear as URLs: paths to functionality in an application that return some data or handle some data that has been provided. The views will be logical structures that handle specific HTTP requests from a given client and return some HTTP response to that client. + +In Flask, views appear as functions; for example, see the `hello_world` view above. For simplicity, here it is again: + +``` +@app.route('/') +def hello_world(): +    """Print 'Hello, world!' as the response body.""" +    return 'Hello, world!' +``` + +When the route of `http://domainname/` is accessed, the client receives the response, "Hello, world!" + +With Flask, a function is marked as a view when it is decorated by `app.route`. In turn, `app.route` adds to the application's central configuration a map from the specified route to the function that runs when that route is accessed. You can use this to start building out the rest of the API. + +Start with a view that handles only `GET` requests, and respond with the JSON representing all the routes that will be accessible and the methods that can be used to access them. + +``` +from flask import jsonify + +@app.route('/api/v1', methods=["GET"]) +def info_view(): +    """List of routes for this API.""" +    output = { +        'info': 'GET /api/v1', +        'register': 'POST /api/v1/accounts', +        'single profile detail': 'GET /api/v1/accounts/', +        'edit profile': 'PUT /api/v1/accounts/', +        'delete profile': 'DELETE /api/v1/accounts/', +        'login': 'POST /api/v1/accounts/login', +        'logout': 'GET /api/v1/accounts/logout', +        "user's tasks": 'GET /api/v1/accounts//tasks', +        "create task": 'POST /api/v1/accounts//tasks', +        "task detail": 'GET /api/v1/accounts//tasks/', +        "task update": 'PUT /api/v1/accounts//tasks/', +        "delete task": 'DELETE /api/v1/accounts//tasks/' +    } +    return jsonify(output) +``` + +Since you want your view to handle one specific type of HTTP request, use `app.route` to add that restriction. The `methods` keyword argument will take a list of strings as a value, with each string a type of possible HTTP method. In practice, you can use `app.route` to restrict to one or more types of HTTP request or accept any by leaving the `methods` keyword argument alone. + +Whatever you intend to return from your view function **must** be a string or an object that Flask turns into a string when constructing a properly formatted HTTP response. The exceptions to this rule are when you're trying to handle redirects and exceptions thrown by your application. What this means for you, the developer, is that you need to be able to encapsulate whatever response you're trying to send back to the client into something that can be interpreted as a string. + +A good structure that contains complexity but can still be stringified is a Python dictionary. Therefore, I recommend that, whenever you want to send some data to the client, you choose a Python `dict` with whatever key-value pairs you need to convey information. To turn that dictionary into a properly formatted JSON response, headers and all, pass it as an argument to Flask's `jsonify` function (`from flask import jsonify`). + +The view function above takes what is effectively a listing of every route that this API intends to handle and sends it to the client whenever the `http://domainname/api/v1` route is accessed. Note that, on its own, Flask supports routing to exactly matching URIs, so accessing that same route with a trailing `/` would create a 404 error. If you wanted to handle both with the same view function, you'd need stack decorators like so: + +``` +@app.route('/api/v1', methods=["GET"]) +@app.route('/api/v1/', methods=["GET"]) +def info_view(): +    # blah blah blah more code +``` + +An interesting case is that if the defined route had a trailing slash and the client asked for the route without the slash, you wouldn't need to double up on decorators. Flask would redirect the client's request appropriately. It's odd that it doesn't work both ways. + +### Flask requests and the DB + +At its base, a web framework's job is to handle incoming HTTP requests and return HTTP responses. The previously written view doesn't really have much to do with HTTP requests aside from the URI that was accessed. It doesn't process any data. Let's look at how Flask behaves when data needs handling. + +The first thing to know is that Flask doesn't provide a separate `request` object to each view function. It has **one** global request object that every view function can use, and that object is conveniently named `request` and is importable from the Flask package. + +The next thing is that Flask's route patterns can have a bit more nuance. One scenario is a hardcoded route that must be matched perfectly to activate a view function. Another scenario is a route pattern that can handle a range of routes, all mapping to one view by allowing a part of that route to be variable. If the route in question has a variable, the corresponding value can be accessed from the same-named variable in the view's parameter list. + +``` +@app.route('/a/sample//route) +def some_view(variable): +    # some code blah blah blah +``` + +To communicate with the database within a view, you must use the `db` object that was populated toward the top of the script. Its `session` attribute is your connection to the database when you want to make changes. If you just want to query for objects, the objects built from `db.Model` have their own database interaction layer through the `query` attribute. + +Finally, any response you want from a view that's more complex than a string must be built deliberately. Previously you built a response using a "jsonified" dictionary, but certain assumptions were made (e.g., 200 status code, status message "OK," Content-Type of "text/plain"). Any special sauce you want in your HTTP response must be added deliberately. + +Knowing these facts about working with Flask views allows you to construct a view whose job is to create new `Task` objects. Let's look at the code (below) and address it piece by piece. + +``` +from datetime import datetime +from flask import request, Response +from flask_sqlalchemy import SQLAlchemy +import json + +from .models import Task, User + +app = Flask(__name__) +app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('DATABASE_URL', '') +db = SQLAlchemy(app) + +INCOMING_DATE_FMT = '%d/%m/%Y %H:%M:%S' + +@app.route('/api/v1/accounts//tasks', methods=['POST']) +def create_task(username): +    """Create a task for one user.""" +    user = User.query.filter_by(username=username).first() +    if user: +        task = Task( +            name=request.form['name'], +            note=request.form['note'], +            creation_date=datetime.now(), +            due_date=datetime.strptime(due_date, INCOMING_DATE_FMT) if due_date else None, +            completed=bool(request.form['completed']), +            user_id=user.id, +        ) +        db.session.add(task) +        db.session.commit() +        output = {'msg': 'posted'} +        response = Response( +            mimetype="application/json", +            response=json.dumps(output), +            status=201 +        ) +        return response +``` + +Let's start with the `@app.route` decorator. The route is `'/api/v1/accounts//tasks'`, where `` is a route variable. Put angle brackets around any part of the route you want to be variable, then include that part of the route on the next line in the parameter list **with the same name**. The only parameters that should be in the parameter list should be the variables in your route. + +Next comes the query: + +``` +user = User.query.filter_by(username=username).first() +``` + +To look for one user by username, conceptually you need to look at all the User objects stored in the database and find the users with the username matching the one that was requested. With Flask, you can ask the `User` object directly through the `query` attribute for the instance matching your criteria. This type of query would provide a list of objects (even if it's only one object or none at all), so to get the object you want, just call `first()`. + +``` +task = Task( +    name=request.form['name'], +    note=request.form['note'], +    creation_date=datetime.now(), +    due_date=datetime.strptime(due_date, INCOMING_DATE_FMT) if due_date else None, +    completed=bool(request.form['completed']), +    user_id=user.id, +) +``` + +Whenever data is sent to the application, regardless of the HTTP method used, that data is stored on the `form` attribute of the `request` object. The name of the field on the frontend will be the name of the key mapped to that data in the `form` dictionary. It'll always come in the form of a string, so if you want your data to be a specific data type, you'll have to make it explicit by casting it as the appropriate type. + +The other thing to note is the assignment of the current user's user ID to the newly instantiated `Task`. This is how that foreign key relationship is maintained. + +``` +db.session.add(task) +db.session.commit() +``` + +Creating a new `Task` instance is great, but its construction has no inherent connection to tables in the database. In order to insert a new row into the corresponding SQL table, you must use the `session` attached to the `db` object. The `db.session.add(task)` stages the new `Task` instance to be added to the table, but doesn't add it yet. While it's done only once here, you can add as many things as you want before committing. The `db.session.commit()` takes all the staged changes, or "commits," and applies them to the corresponding tables in the database. + +``` +output = {'msg': 'posted'} +response = Response( +    mimetype="application/json", +    response=json.dumps(output), +    status=201 +) +``` + +The response is an actual instance of a `Response` object with its `mimetype`, body, and `status` set deliberately. The goal for this view is to alert the user they created something new. Seeing how this view is supposed to be part of a backend API that sends and receives JSON, the response body must be JSON serializable. A dictionary with a simple string message should suffice. Ensure that it's ready for transmission by calling `json.dumps` on your dictionary, which will turn your Python object into valid JSON. This is used instead of `jsonify`, as `jsonify` constructs an actual response object using its input as the response body. In contrast, `json.dumps` just takes a given Python object and converts it into a valid JSON string if possible. + +By default, the status code of any response sent with Flask will be `200`. That will work for most circumstances, where you're not trying to send back a specific redirection-level or error-level message. Since this case explicitly lets the frontend know when a new item has been created, set the status code to be `201`, which corresponds to creating a new thing. + +And that's it! That's a basic view for creating a new `Task` object in Flask given the current setup of your To-Do List application. Similar views could be constructed for listing, editing, and deleting tasks, but this example offers an idea of how it could be done. + +### The bigger picture + +There is much more that goes into an application than one view for creating new things. While I haven't discussed anything about authorization/authentication systems, testing, database migration management, cross-origin resource sharing, etc., the details above should give you more than enough to start digging into building your own Flask applications. + +Learn more Python at [PyCon Cleveland 2018][12]. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/4/flask + +作者：[Nicholas Hunt-Walker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/nhuntwalker +[b]: https://github.com/lujun9972 +[1]: https://www.fullstackpython.com/web-frameworks.html +[2]: http://flask.pocoo.org/ +[3]: http://www.tornadoweb.org/en/stable/ +[4]: https://trypyramid.com/ +[5]: https://www.djangoproject.com/ +[6]: https://pypi.python.org +[7]: https://docs.python.org/3/distutils/setupscript.html +[8]: https://www.python.org/dev/peps/pep-0249/ +[9]: https://www.sqlalchemy.org/ +[10]: https://flask-migrate.readthedocs.io/en/latest/ +[11]: https://flask-alembic.readthedocs.io/en/stable/ +[12]: https://us.pycon.org/2018/ diff --git a/sources/tech/20180416 Cgo and Python.md b/sources/tech/20180416 Cgo and Python.md index e5688d43c8..422f510949 100644 --- a/sources/tech/20180416 Cgo and Python.md +++ b/sources/tech/20180416 Cgo and Python.md @@ -1,3 +1,4 @@ +translating by name1e5s Cgo and Python ============================================================ diff --git a/sources/tech/20180417 How To Browse Stack Overflow From Terminal.md b/sources/tech/20180417 How To Browse Stack Overflow From Terminal.md deleted file mode 100644 index 0bd7789d87..0000000000 --- a/sources/tech/20180417 How To Browse Stack Overflow From Terminal.md +++ /dev/null @@ -1,140 +0,0 @@ -translating---geekpi - -How To Browse Stack Overflow From Terminal -====== - -![](https://www.ostechnix.com/wp-content/uploads/2018/04/how2-720x340.png) -A while ago, we have written about [**SoCLI**][1], a python script to search and browse Stack Overflow website from command line. Today, we will discuss about a similar tool named **“how2”**. It is a command line utility to browse Stack Overflow from Terminal. You can query in the plain English as the way you do in [**Google search**][2] and it uses Google and Stackoverflow APIs to search for the given queries. It is free and open source utility written using NodeJS. - -### Browse Stack Overflow From Terminal Using how2 - -Since how2 is a NodeJS package, we can install it using Npm package manager. If you haven’t installed Npm and NodeJS already, refer the following guide. - -After installing Npm and NodeJS, run the following command to install how2 utility. -``` -$ npm install -g how2 - -``` - -Now let us see how to browse Stack Overflow uisng this program. The typical usage to search through Stack Overflow site using “how2” utility is: -``` -$ how2 - -``` - -For example, I am going to search for how to create tgz archive. -``` -$ how2 create archive tgz - -``` - -Oops! I get the following error. -``` -/home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/transport.js:59 -Transport.prototype.__proto__ = EventEmitter.prototype; - ^ - - TypeError: Cannot read property 'prototype' of undefined - at Object. (/home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/transport.js:59:46) - at Module._compile (internal/modules/cjs/loader.js:654:30) - at Object.Module._extensions..js (internal/modules/cjs/loader.js:665:10) - at Module.load (internal/modules/cjs/loader.js:566:32) - at tryModuleLoad (internal/modules/cjs/loader.js:506:12) - at Function.Module._load (internal/modules/cjs/loader.js:498:3) - at Module.require (internal/modules/cjs/loader.js:598:17) - at require (internal/modules/cjs/helpers.js:11:18) - at Object. (/home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/stream.js:8:17) - at Module._compile (internal/modules/cjs/loader.js:654:30) - -``` - -I may be a bug. I hope it gets fixed in the future versions. However, I find a workaround posted [**here**][3]. - -To fix this error temporarily, you need to edit the **transport.js** file using command: -``` -$ vi /home/sk/.nvm/versions/node/v9.11.1/lib/node_modules/how2/node_modules/devnull/transports/transport.js - -``` - -The actual path of this file will be displayed in your error output. Replace the above file path with your own. Then find the following line: -``` -var EventEmitter = process.EventEmitter; - -``` - -and replace it with following line: -``` -var EventEmitter = require('events'); - -``` - -Press ESC and type **:wq** to save and quit the file. - -Now search again the query. -``` -$ how2 create archive tgz - -``` - -Here is the sample output from my Ubuntu system. - -[![][4]][5] - -If the answer you’re looking for is not displayed in the above output, press **SPACE BAR** key to start the interactive search where you can go through all suggested questions and answers from the Stack Overflow site. - -[![][4]][6] - -Use UP/DOWN arrows to move between the results. Once you got the right answer/question, hit SPACE BAR or ENTER key to open it in the Terminal. - -[![][4]][7] - -To go back and exit, press **ESC**. - -**Search answers for specific language** - -If you don’t specify a language it **defaults to Bash** unix command line and give you immediately the most likely answer as above. You can also narrow the results to a specific language, for example perl, python, c, Java etc. - -For instance, to search for queries related to “Python” language only using **-l** flag as shown below. -``` -$ how2 -l python linked list - -``` - -[![][4]][8] - -To get a quick help, type: -``` -$ how2 -h - -``` - -### Conclusion - -The how2 utility is a basic command line program to quickly search for questions and answers from Stack Overflow without leaving your Terminal and it does this job pretty well. However, it is just CLI browser for Stack overflow. For some advanced features such as searching most voted questions, searching queries using multiple tags, colored interface, submitting a new question and viewing questions stats etc., **SoCLI** is good to go. - -And, that’s all for now. Hope this was useful. I will be soon here with another useful guide. Until then, stay tuned with OSTechNix! - -Cheers! - - - --------------------------------------------------------------------------------- - -via: https://www.ostechnix.com/how-to-browse-stack-overflow-from-terminal/ - -作者：[SK][a] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) -选题：[lujun9972](https://github.com/lujun9972) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.ostechnix.com/author/sk/ -[1]:https://www.ostechnix.com/search-browse-stack-overflow-website-commandline/ -[2]:https://www.ostechnix.com/google-search-navigator-enhance-keyboard-navigation-in-google-search/ -[3]:https://github.com/santinic/how2/issues/79 -[4]:data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 -[5]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-1.png -[6]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-2.png -[7]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-3.png -[8]:http://www.ostechnix.com/wp-content/uploads/2018/04/stack-overflow-4.png diff --git a/sources/tech/20180419 Migrating to Linux- Network and System Settings.md b/sources/tech/20180419 Migrating to Linux- Network and System Settings.md deleted file mode 100644 index f3930f1777..0000000000 --- a/sources/tech/20180419 Migrating to Linux- Network and System Settings.md +++ /dev/null @@ -1,116 +0,0 @@ -Migrating to Linux: Network and System Settings -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/animals-birds-flock-55832.jpg?itok=NUGAyhDO) -In this series, we provide an overview of fundamentals to help you successfully make the transition to Linux from another operating system. If you missed the earlier articles in the series, you can find them here: - -[Part 1 - An Introduction][1] - -[Part 2 - Disks, Files, and Filesystems][2] - -[Part 3 - Graphical Environments][3] - -[Part 4 - The Command Line][4] - -[Part 5 - Using sudo][5] - -[Part 6 - Installing Software][6] - -Linux gives you a lot of control over network and system settings. On your desktop, Linux lets you tweak just about anything on the system. Most of these settings are exposed in plain text files under the /etc directory. Here I describe some of the most common settings you’ll use on your desktop Linux system. - -A lot of settings can be found in the Settings program, and the available options will vary by Linux distribution. Usually, you can change the background, tweak sound volume, connect to printers, set up displays, and more. While I won't talk about all of the settings here, you can certainly explore what's in there. - -### Connect to the Internet - -Connecting to the Internet in Linux is often fairly straightforward. If you are wired through an Ethernet cable, Linux will usually get an IP address and connect automatically when the cable is plugged in or at startup if the cable is already connected. - -If you are using wireless, in most distributions there is a menu, either in the indicator panel or in settings (depending on your distribution), where you can select the SSID for your wireless network. If the network is password protected, it will usually prompt you for the password. Afterward, it connects, and the process is fairly smooth. - -You can adjust network settings in the graphical environment by going into settings. Sometimes this is called System Settings or just Settings. Often you can easily spot the settings program because its icon is a gear or a picture of tools (Figure 1). - - -![Network Settings][8] - -Figure 1: Gnome Desktop Network Settings Indicator Icon. - -[Used with permission][9] - -### Network Interface Names - -Under Linux, network devices have names. Historically, these are given names like eth0 and wlan0 -- or Ethernet and wireless, respectively. Newer Linux systems have been using different names that appear more esoteric, like enp4s0 and wlp5s0. If the name starts with en, it's a wired Ethernet interface. If it starts with wl, it's a wireless interface. The rest of the letters and numbers reflect how the device is connected to hardware. - -### Network Management from the Command Line - -If you want more control over your network settings, or if you are managing network connections without a graphical desktop, you can also manage the network from the command line. - -Note that the most common service used to manage networks in a graphical desktop is the Network Manager, and Network Manager will often override setting changes made on the command line. If you are using the Network Manager, it's best to change your settings in its interface so it doesn't undo the changes you make from the command line or someplace else. - -Changing settings in the graphical environment is very likely to be interacting with the Network Manager, and you can also change Network Manager settings from the command line using the tool called nmtui. The nmtui tool provides all the settings that you find in the graphical environment but gives it in a text-based semi-graphical interface that works on the command line (Figure 2). - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/figure-2_0.png?itok=1QVjDdbJ) - -On the command line, there is an older tool called ifconfig to manage networks and a newer one called ip. On some distributions, ifconfig is considered to be deprecated and is not even installed by default. On other distributions, ifconfig is still in use. - -Here are some commands that will allow you to display and change network settings: - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/screen_shot_2018-04-17_at_3.11.48_pm.png?itok=EZsjb-GQ) - -### Process and System Information - -In Windows, you can go into the Task Manager to see a list of the all the programs and services that are running. You can also stop programs from running. And you can view system performance in some of the tabs displayed there. - -You can do similar things in Linux both from the command line and from graphical tools. In Linux, there are a few graphical tools available depending on your distribution. The most common ones are System Monitor or KSysGuard. In these tools, you can see system performance, see a list of processes, and even kill processes (Figure 3). - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/figure-3_2.png?itok=ePeXj9PA) - -In these tools, you can also view global network traffic on your system (Figure 4). - - -![System Monitor][11] - -Figure 4: Screenshot of Gnome System Monitor. - -[Used with permission][9] - -### Managing Process and System Usage - -There are also quite a few tools you can use from the command line. The command ps can be used to list processes on your system. By default, it will list processes running in your current terminal session. But you can list other processes by giving it various command line options. You can get more help on ps with the commands info ps, or man ps. - -Most folks though want to get a list of processes because they would like to stop the one that is using up too much memory or CPU time. In this case, there are two commands that make this task much easier. These are top and htop (Figure 5). - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/figure-5_0.png?itok=2nm5EmAl) - -The top and htop tools work very similarly to each other. These commands update their list every second or two and re-sort the list so that the task using the most CPU is at the top. You can also change the sorting to sort by other resources as well such as memory usage. - -In either of these programs (top and htop), you can type '?' to get help, and 'q' to quit. With top, you can press 'k' to kill a process and then type in the unique PID number for the process to kill it. - -With htop, you can highlight a task by pressing down arrow or up arrow to move the highlight bar, and then press F9 to kill the task followed by Enter to confirm. - -The information and tools provided in this series will help you get started with Linux. With a little time and patience, you'll feel right at home. - -Learn more about Linux through the free ["Introduction to Linux" ][12]course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/learn/2018/4/migrating-linux-network-and-system-settings - -作者：[John Bonesio][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/johnbonesio -[1]:https://www.linux.com/blog/learn/intro-to-linux/2017/10/migrating-linux-introduction -[2]:https://www.linux.com/blog/learn/intro-to-linux/2017/11/migrating-linux-disks-files-and-filesystems -[3]:https://www.linux.com/blog/learn/2017/12/migrating-linux-graphical-environments -[4]:https://www.linux.com/blog/learn/2018/1/migrating-linux-command-line -[5]:https://www.linux.com/blog/learn/2018/3/migrating-linux-using-sudo -[6]:https://www.linux.com/blog/learn/2018/3/migrating-linux-installing-software -[7]:https://www.linux.com/files/images/figure-1png-2 -[8]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/figure-1_2.png?itok=J-C6q-t5 (Network Settings) -[9]:https://www.linux.com/licenses/category/used-permission -[10]:https://www.linux.com/files/images/figure-4png-1 -[11]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/figure-4_1.png?itok=boI-L1mF (System Monitor) -[12]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20180420 How To Remove Password From A PDF File in Linux.md b/sources/tech/20180420 How To Remove Password From A PDF File in Linux.md deleted file mode 100644 index 0e4318c858..0000000000 --- a/sources/tech/20180420 How To Remove Password From A PDF File in Linux.md +++ /dev/null @@ -1,220 +0,0 @@ -How To Remove Password From A PDF File in Linux -====== - -![](https://www.ostechnix.com/wp-content/uploads/2018/04/Remove-Password-From-A-PDF-File-720x340.png) -Today I happen to share a password protected PDF file to one of my friend. I knew the password of that PDF file, but I didn’t want to disclose it. Instead, I just wanted to remove the password and send the file to him. I started to looking for some easy ways to remove the password protection from the pdf files on Internet. After a quick google search, I came up with four methods to remove password from a PDF file in Linux. The funny thing is I had already done it few years ago and I almost forgot it. If you’re wondering how to remove password from a PDF file in Linux, read on! It is not that difficult. - -### Remove Password From A PDF File in Linux - -**Method 1 – Using Qpdf** - -The **Qpdf** is a PDF transformation software which is used to encrypt and decrypt PDF files, convert PDF files to another equivalent pdf files. Qpdf is available in the default repositories of most Linux distributions, so you can install it using the default package manager. - -For example, Qpdf can be installed on Arch Linux and its variants using [**pacman**][1] as shown below. -``` -$ sudo pacman -S qpdf - -``` - -On Debian, Ubuntu, Linux Mint: -``` -$ sudo apt-get install qpdf - -``` - -Now let us remove the password from a pdf file using qpdf. - -I have a password-protected PDF file named **“secure.pdf”**. Whenever I open this file, it prompts me to enter the password to display its contents. - -![][3] - -I know the password of the above pdf file. However, I don’t want to share the password with anyone. So what I am going to do is to simply remove the password of the PDF file using Qpdf utility with following command. -``` -$ qpdf --password='123456' --decrypt secure.pdf output.pdf - -``` - -Quite easy, isn’t it? Yes, it is! Here, **123456** is the password of the **secure.pdf** file. Replace the password with your own. - -**Method 2 – Using Pdftk** - -**Pdftk** is yet another great software for manipulating pdf documents. Pdftk can do almost all sort of pdf operations, such as; - - * Encrypt and decrypt pdf files. - * Merge PDF documents. - * Collate PDF page Scans. - * Split PDF pages. - * Rotate PDF files or pages. - * Fill PDF forms with X/FDF data and/or flatten forms. - * Generate FDF data stencils from PDF forms. - * Apply a background watermark or a foreground stamp. - * Report PDF metrics, bookmarks and metadata. - * Add/update PDF bookmarks or metadata. - * Attach files to PDF pages or the PDF document. - * Unpack PDF attachments. - * Burst a PDF file into single pages. - * Compress and decompress page streams. - * Repair corrupted PDF file. - - - -Pddftk is available in AUR, so you can install it using any AUR helper programs on Arch Linux its derivatives. - -Using [**Pacaur**][4]: -``` -$ pacaur -S pdftk - -``` - -Using [**Packer**][5]: -``` -$ packer -S pdftk - -``` - -Using [**Trizen**][6]: -``` -$ trizen -S pdftk - -``` - -Using [**Yay**][7]: -``` -$ yay -S pdftk - -``` - -Using [**Yaourt**][8]: -``` -$ yaourt -S pdftk - -``` - -On Debian, Ubuntu, Linux Mint, run: -``` -$ sudo apt-get instal pdftk - -``` - -On CentOS, Fedora, Red Hat: - -First, Install EPEL repository: -``` -$ sudo yum install epel-release - -``` - -Or -``` -$ sudo dnf install epel-release - -``` - -Then install PDFtk application using command: -``` -$ sudo yum install pdftk - -``` - -Or -``` -$ sudo dnf install pdftk - -``` - -Once pdftk installed, you can remove the password from a pdf document using command: -``` -$ pdftk secure.pdf input_pw 123456 output output.pdf - -``` - -Replace ‘123456’ with your correct password. This command decrypts the “secure.pdf” file and create an equivalent non-password protected file named “output.pdf”. - -**Also read:** - -**Method 3 – Using Poppler** - -**Poppler** is a PDF rendering library based on the xpdf-3.0 code base. It contains the following set of command line utilities for manipulating PDF documents. - - * **pdfdetach** – lists or extracts embedded files. - * **pdffonts** – font analyzer. - * **pdfimages** – image extractor. - * **pdfinfo** – document information. - * **pdfseparate** – page extraction tool. - * **pdfsig** – verifies digital signatures. - * **pdftocairo** – PDF to PNG/JPEG/PDF/PS/EPS/SVG converter using Cairo. - * **pdftohtml** – PDF to HTML converter. - * **pdftoppm** – PDF to PPM/PNG/JPEG image converter. - * **pdftops** – PDF to PostScript (PS) converter. - * **pdftotext** – text extraction. - * **pdfunite** – document merging tool. - - - -For the purpose of this guide, we only use the “pdftops” utility. - -To install Poppler on Arch Linux based distributions, run: -``` -$ sudo pacman -S poppler - -``` - -On Debian, Ubuntu, Linux Mint: -``` -$ sudo apt-get install poppler-utils - -``` - -On RHEL, CentOS, Fedora: -``` -$ sudo yum install poppler-utils - -``` - -Once Poppler installed, run the following command to decrypt the password protected pdf file and create a new equivalent file named output.pdf. -``` -$ pdftops -upw 123456 secure.pdf output.pdf - -``` - -Again, replace ‘123456’ with your pdf password. - -As you might noticed in all above methods, we just converted the password protected pdf file named “secure.pdf” to another equivalent pdf file named “output.pdf”. Technically speaking, we really didn’t remove the password from the source file, instead we decrypted it and saved it as another equivalent pdf file without password protection. - -**Method 4 – Print to a file -** - -This is the easiest method in all of the above methods. You can use your existing PDF viewer such as Atril document viewer, Evince etc., and print the password protected pdf file to another file. - -Open the password protected file in your PDF viewer application. Go to **File - > Print**. And save the pdf file in any location of your choice. - -![][9] - -And, that’s all. Hope this was useful. Do you know/use any other methods to remove the password protection from PDF files? Let us know in the comment section below. - -More good stuffs to come. Stay tuned! - -Cheers! - - - --------------------------------------------------------------------------------- - -via: https://www.ostechnix.com/how-to-remove-password-from-a-pdf-file-in-linux/ - -作者：[SK][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.ostechnix.com/author/sk/ -[1]:https://www.ostechnix.com/getting-started-pacman/ -[2]:data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 -[3]:http://www.ostechnix.com/wp-content/uploads/2018/04/Remove-Password-From-A-PDF-File-1.png -[4]:https://www.ostechnix.com/install-pacaur-arch-linux/ -[5]:https://www.ostechnix.com/install-packer-arch-linux-2/ -[6]:https://www.ostechnix.com/trizen-lightweight-aur-package-manager-arch-based-systems/ -[7]:https://www.ostechnix.com/yay-found-yet-another-reliable-aur-helper/ -[8]:https://www.ostechnix.com/install-yaourt-arch-linux/ diff --git a/sources/tech/20180422 Command Line Tricks For Data Scientists - kade killary.md b/sources/tech/20180422 Command Line Tricks For Data Scientists - kade killary.md deleted file mode 100644 index aea3b6b035..0000000000 --- a/sources/tech/20180422 Command Line Tricks For Data Scientists - kade killary.md +++ /dev/null @@ -1,526 +0,0 @@ -Command Line Tricks For Data Scientists • kade killary -====== - -![](https://i.imgur.com/0mzQMcB.png) - -For many data scientists, data manipulation begins and ends with Pandas or the Tidyverse. In theory, there is nothing wrong with this notion. It is, after all, why these tools exist in the first place. Yet, these options can often be overkill for simple tasks like delimiter conversion. - -Aspiring to master the command line should be on every developer’s list, especially data scientists. Learning the ins and outs of your shell will undeniably make you more productive. Beyond that, the command line serves as a great history lesson in computing. For instance, awk - a data-driven scripting language. Awk first appeared in 1977 with the help of [Brian Kernighan][1], the K in the legendary [K&R book][2]. Today, some near 50 years later, awk remains relevant with [new books][3] still appearing every year! Thus, it’s safe to assume that an investment in command line wizardry won’t depreciate any time soon. - -### What We’ll Cover - - * ICONV - * HEAD - * TR - * WC - * SPLIT - * SORT & UNIQ - * CUT - * PASTE - * JOIN - * GREP - * SED - * AWK - - - -### ICONV - -File encodings can be tricky. For the most part files these days are all UTF-8 encoded. To understand some of the magic behind UTF-8, check out this [excellent video][4]. Nonetheless, there are times where we receive a file that isn’t in this format. This can lead to some wonky attempts at swapping the encoding schema. Here, `iconv` is a life saver. Iconv is a simple program that will take text in one encoding and output the text in another. -``` -# Converting -f (from) latin1 (ISO-8859-1) -# -t (to) standard UTF_8 - -iconv -f ISO-8859-1 -t UTF-8 < input.txt > output.txt - -``` - - * Useful options: - - * `iconv -l` list all known encodings - * `iconv -c` silently discard characters that cannot be converted - - - -### HEAD - -If you are a frequent Pandas user then `head` will be familiar. Often when dealing with new data the first thing we want to do is get a sense of what exists. This leads to firing up Pandas, reading in the data and then calling `df.head()` \- strenuous, to say the least. Head, without any flags, will print out the first 10 lines of a file. The true power of `head` lies in testing out cleaning operations. For instance, if we wanted to change the delimiter of a file from commas to pipes. One quick test would be: `head mydata.csv | sed 's/,/|/g'`. -``` -# Prints out first 10 lines - -head filename.csv - -# Print first 3 lines - -head -n 3 filename.csv - -``` - - * Useful options: - - * `head -n` print a specific number of lines - * `head -c` print a specific number of bytes - - - -### TR - -Tr is analogous to translate. This powerful utility is a workhorse for basic file cleaning. An ideal use case is for swapping out the delimiters within a file. -``` -# Converting a tab delimited file into commas - -cat tab_delimited.txt | tr "\t" "," comma_delimited.csv - -``` - -Another feature of `tr` is all the built in `[:class:]` variables at your disposal. These include: -``` -[:alnum:] all letters and digits -[:alpha:] all letters -[:blank:] all horizontal whitespace -[:cntrl:] all control characters -[:digit:] all digits -[:graph:] all printable characters, not including space -[:lower:] all lower case letters -[:print:] all printable characters, including space -[:punct:] all punctuation characters -[:space:] all horizontal or vertical whitespace -[:upper:] all upper case letters -[:xdigit:] all hexadecimal digits - -``` - -You can chain a variety of these together to compose powerful programs. The following is a basic word count program you could use to check your READMEs for overuse. -``` -cat README.md | tr "[:punct:][:space:]" "\n" | tr "[:upper:]" "[:lower:]" | grep . | sort | uniq -c | sort -nr - -``` - -Another example using basic regex: -``` -# Converting all upper case letters to lower case - -cat filename.csv | tr '[A-Z]' '[a-z]' - -``` - - * Useful options: - - * `tr -d` delete characters - * `tr -s` squeeze characters - * `\b` backspace - * `\f` form feed - * `\v` vertical tab - * `\NNN` character with octal value NNN - - - -### WC - -Word count. Its value is primarily derived from the `-l` flag, which will give you the line count. -``` -# Will return number of lines in CSV - -wc -l gigantic_comma.csv - -``` - -This tool comes in handy to confirm the output of various commands. So, if we were to convert the delimiters within a file and then run `wc -l` we would expect the total lines to be the same. If not, then we know something went wrong. - - * Useful options: - - * `wc -c` print the byte counts - * `wc -m` print the character counts - * `wc -L` print length of longest line - * `wc -w` print word counts - - - -### SPLIT - -File sizes can range dramatically. And depending on the job, it could be beneficial to split up the file - thus `split`. The basic syntax for split is: -``` -# We will split our CSV into new_filename every 500 lines - -split -l 500 filename.csv new_filename_ - -# filename.csv -# ls output -# new_filename_aaa -# new_filename_aab -# new_filename_aac - -``` - -Two quirks are the naming convention and lack of file extensions. The suffix convention can be numeric via the `-d` flag. To add file extensions, you’ll need to run the following `find` command. It will change the names of ALL files within the current directory by appending `.csv`, so be careful. -``` -find . -type f -exec mv '{}' '{}'.csv \; - -# ls output -# filename.csv.csv -# new_filename_aaa.csv -# new_filename_aab.csv -# new_filename_aac.csv - -``` - - * Useful options: - - * `split -b` split by certain byte size - * `split -a` generate suffixes of length N - * `split -x` split using hex suffixes - - - -### SORT & UNIQ - -The preceding commands are obvious: they do what they say they do. These two provide the most punch in tandem (i.e. unique word counts). This is due to `uniq`, which only operates on duplicate adjacent lines. Thus, the reason to `sort` before piping the output through. One interesting note is that `sort -u` will achieve the same results as the typical `sort file.txt | uniq` pattern. - -Sort does have a sneakily useful ability for data scientists: the ability to sort an entire CSV based on a particular column. -``` -# Sorting a CSV file by the second column alphabetically - -sort -t"," -k2,2 filename.csv - -# Numerically - -sort -t"," -k2n,2 filename.csv - -# Reverse order - -sort -t"," -k2nr,2 filename.csv - -``` - -The `-t` option here is to specify the comma as our delimiter. More often than not spaces or tabs are assumed. Furthermore, the `-k` flag is for specifying our key. The syntax for this is `-km,n`, with `m` being the starting field and `n` being the last. - - * Useful options: - - * `sort -f` ignore case - * `sort -r` reverse sort order - * `sort -R` scramble order - * `uniq -c` count number of occurrences - * `uniq -d` only print duplicate lines - - - -### CUT - -Cut is for removing columns. To illustrate, if we only wanted the first and third columns. -``` -cut -d, -f 1,3 filename.csv - -``` - -To select every column other than the first. -``` -cut -d, -f 2- filename.csv - -``` - -In combination with other commands, `cut` serves as a filter. -``` -# Print first 10 lines of column 1 and 3, where "some_string_value" is present - -head filename.csv | grep "some_string_value" | cut -d, -f 1,3 - -``` - -Finding out the number of unique values within the second column. -``` -cat filename.csv | cut -d, -f 2 | sort | uniq | wc -l - -# Count occurences of unique values, limiting to first 10 results - -cat filename.csv | cut -d, -f 2 | sort | uniq -c | head - -``` - -### PASTE - -Paste is a niche command with an interesting function. If you have two files that you need merged, and they are already sorted, `paste` has you covered. -``` -# names.txt -adam -john -zach - -# jobs.txt -lawyer -youtuber -developer - -# Join the two into a CSV - -paste -d ',' names.txt jobs.txt > person_data.txt - -# Output -adam,lawyer -john,youtuber -zach,developer - -``` - -For a more SQL_-esque variant, see below. - -### JOIN - -Join is a simplistic, quasi-tangential, SQL. The largest differences being that `join` will return all columns and matches can only be on one field. By default, `join` will try and use the first column as the match key. For a different result, the following syntax is necessary: -``` -# Join the first file (-1) by the second column -# and the second file (-2) by the first - -join -t"," -1 2 -2 1 first_file.txt second_file.txt - -``` - -The standard join is an inner join. However, an outer join is also viable through the `-a` flag. Another noteworthy quirk is the `-e` flag, which can be used to substitute a value if a missing field is found. -``` -# Outer join, replace blanks with NULL in columns 1 and 2 -# -o which fields to substitute - 0 is key, 1.1 is first column, etc... - -join -t"," -1 2 -a 1 -a2 -e ' NULL' -o '0,1.1,2.2' first_file.txt second_file.txt - -``` - -Not the most user-friendly command, but desperate times, desperate measures. - - * Useful options: - - * `join -a` print unpairable lines - * `join -e` replace missing input fields - * `join -j` equivalent to `-1 FIELD -2 FIELD` - - - -### GREP - -Global search for a regular expression and print, or `grep`; likely, the most well known command, and with good reason. Grep has a lot of power, especially for finding your way around large codebases. Within the realm of data science, it acts as a refining mechanism for other commands. Although its standard usage is valuable as well. -``` -# Recursively search and list all files in directory containing 'word' - -grep -lr 'word' . - -# List number of files containing word - -grep -lr 'word' . | wc -l - -``` - -Count total number of lines containing word / pattern. -``` -grep -c 'some_value' filename.csv - -# Same thing, but in all files in current directory by file name - -grep -c 'some_value' * - -``` - -Grep for multiple values using the or operator - `\|`. -``` -grep "first_value\|second_value" filename.csv - -``` - - * Useful options - - * `alias grep="grep --color=auto"` make grep colorful - * `grep -E` use extended regexps - * `grep -w` only match whole words - * `grep -l` print name of files with match - * `grep -v` inverted matching - - - -### THE BIG GUNS - -Sed and Awk are the two most powerful commands in this article. For brevity, I’m not going to go into exhausting detail about either. Instead, I will cover a variety of commands that prove their impressive might. If you want to know more, [there is a book][5] just for that. - -### SED - -At its core `sed` is a stream editor. It excels at substitutions, but can also be leveraged for all out refactoring. - -The most basic `sed` command consists of `s/old/new/g`. This translates to search for old value, replace with new globally. Without the `/g` our command would terminate after the first occurrence. - -To get a quick taste of the power lets dive into an example. In this scenario you’ve been given the following file: -``` -balance,name -$1,000,john -$2,000,jack - -``` - -The first thing we may want to do is remove the dollar signs. The `-i` flag indicates in-place. The `''` is to indicate a zero-length file extension, thus overwriting our initial file. Ideally, you would test each of these individually and then output to a new file. -``` -sed -i '' 's/\$//g' data.txt - -# balance,name -# 1,000,john -# 2,000,jack - -``` - -Next up, the commas in our `balance` column values. -``` -sed -i '' 's/\([0-9]\),\([0-9]\)/\1\2/g' data.txt - -# balance,name -# 1000,john -# 2000,jack - -``` - -Lastly, Jack up and decided to quit one day. So, au revoir, mon ami. -``` -sed -i '' '/jack/d' data.txt - -# balance,name -# 1000,john - -``` - -As you can see, `sed` packs quite a punch, but the fun doesn’t stop there. - -### AWK - -The best for last. Awk is much more than a simple command: it is a full-blown language. Of everything covered in this article, `awk` is by far the coolest. If you find yourself impressed there are loads of great resources - see [here][6], [here][7] and [here][8]. - -Common use cases for `awk` include: - - * Text processing - * Formatted text reports - * Performing arithmetic operations - * Performing string operations - - - -Awk can parallel `grep` in its most nascent form. -``` -awk '/word/' filename.csv - -``` - -Or with a little more magic the combination of `grep` and `cut`. Here, `awk` prints the third and fourth column, tab separated, for all lines with our word. `-F,` merely changes our delimiter to a comma. -``` -awk -F, '/word/ { print $3 "\t" $4 }' filename.csv - -``` - -Awk comes with a lot of nifty variables built-in. For instance, `NF` \- number of fields - and `NR` \- number of records. To get the fifty-third record in a file: -``` -awk -F, 'NR == 53' filename.csv - -``` - -An added wrinkle is the ability to filter based off of one or more values. The first example, below, will print the line number and columns for records where the first column equals string. -``` -awk -F, ' $1 == "string" { print NR, $0 } ' filename.csv - -# Filter based off of numerical value in second column - -awk -F, ' $2 == 1000 { print NR, $0 } ' filename.csv - -``` - -Multiple numerical expressions: -``` -# Print line number and columns where column three greater -# than 2005 and column five less than one thousand - -awk -F, ' $3 >= 2005 && $5 <= 1000 { print NR, $0 } ' filename.csv - -``` - -Sum the third column: -``` -awk -F, '{ x+=$3 } END { print x }' filename.csv - -``` - -The sum of the third column, for values where the first column equals “something”. -``` -awk -F, '$1 == "something" { x+=$3 } END { print x }' filename.csv - -``` - -Get the dimensions of a file: -``` -awk -F, 'END { print NF, NR }' filename.csv - -# Prettier version - -awk -F, 'BEGIN { print "COLUMNS", "ROWS" }; END { print NF, NR }' filename.csv - -``` - -Print lines appearing twice: -``` -awk -F, '++seen[$0] == 2' filename.csv - -``` - -Remove duplicate lines: -``` -# Consecutive lines -awk 'a !~ $0; {a=$0}'] - -# Nonconsecutive lines -awk '! a[$0]++' filename.csv - -# More efficient -awk '!($0 in a) {a[$0];print} - -``` - -Substitute multiple values using built-in function `gsub()`. -``` -awk '{gsub(/scarlet|ruby|puce/, "red"); print}' - -``` - -This `awk` command will combine multiple CSV files, ignoring the header and then append it at the end. -``` -awk 'FNR==1 && NR!=1{next;}{print}' *.csv > final_file.csv - -``` - -Need to downsize a massive file? Welp, `awk` can handle that with help from `sed`. Specifically, this command breaks one big file into multiple smaller ones based on a line count. This one-liner will also add an extension. -``` -sed '1d;$d' filename.csv | awk 'NR%NUMBER_OF_LINES==1{x="filename-"++i".csv";}{print > x}' - -# Example: splitting big_data.csv into data_(n).csv every 100,000 lines - -sed '1d;$d' big_data.csv | awk 'NR%100000==1{x="data_"++i".csv";}{print > x}' - -``` - -### CLOSING - -The command line boasts endless power. The commands covered in this article are enough to elevate you from zero to hero in no time. Beyond those covered, there are many utilities to consider for daily data operations. [Csvkit][9], [xsv][10] and [q][11] are three of note. If you’re looking to take an even deeper dive into command line data science, then look no further than [this book][12]. It’s also available online [for free][13]! - --------------------------------------------------------------------------------- - -via: http://kadekillary.work/post/cli-4-ds/ - -作者：[Kade Killary][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:http://kadekillary.work/authors/kadekillary -[1]:https://en.wikipedia.org/wiki/Brian_Kernighan -[2]:https://en.wikipedia.org/wiki/The_C_Programming_Language -[3]:https://www.amazon.com/Learning-AWK-Programming-cutting-edge-text-processing-ebook/dp/B07BT98HDS -[4]:https://www.youtube.com/watch?v=MijmeoH9LT4 -[5]:https://www.amazon.com/sed-awk-Dale-Dougherty/dp/1565922255/ref=sr_1_1?ie=UTF8&qid=1524381457&sr=8-1&keywords=sed+and+awk -[6]:https://www.amazon.com/AWK-Programming-Language-Alfred-Aho/dp/020107981X/ref=sr_1_1?ie=UTF8&qid=1524388936&sr=8-1&keywords=awk -[7]:http://www.grymoire.com/Unix/Awk.html -[8]:https://www.tutorialspoint.com/awk/index.htm -[9]:http://csvkit.readthedocs.io/en/1.0.3/ -[10]:https://github.com/BurntSushi/xsv -[11]:https://github.com/harelba/q -[12]:https://www.amazon.com/Data-Science-Command-Line-Time-Tested/dp/1491947853/ref=sr_1_1?ie=UTF8&qid=1524390894&sr=8-1&keywords=data+science+at+the+command+line -[13]:https://www.datascienceatthecommandline.com/ diff --git a/sources/tech/20180514 An introduction to the Pyramid web framework for Python.md b/sources/tech/20180514 An introduction to the Pyramid web framework for Python.md new file mode 100644 index 0000000000..a16e604774 --- /dev/null +++ b/sources/tech/20180514 An introduction to the Pyramid web framework for Python.md @@ -0,0 +1,617 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (An introduction to the Pyramid web framework for Python) +[#]: via: (https://opensource.com/article/18/5/pyramid-framework) +[#]: author: (Nicholas Hunt-Walker https://opensource.com/users/nhuntwalker) +[#]: url: ( ) + +An introduction to the Pyramid web framework for Python +====== +In the second part in a series comparing Python frameworks, learn about Pyramid. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/pyramid.png?itok=hX73LWtl) + +In the [first article][1] in this four-part series comparing different Python web frameworks, I explained how to create a To-Do List web application in the [Flask][2] web framework. In this second article, I'll do the same task with the [Pyramid][3] web framework. Future articles will look at [Tornado][4] and [Django][5]; as I go along, I'll explore more of the differences among them. + +### Installing, starting up, and doing configuration + +Self-described as "the start small, finish big, stay finished framework," Pyramid is much like Flask in that it takes very little effort to get it up and running. In fact, you'll recognize many of the same patterns as you build out this application. The major difference between the two, however, is that Pyramid comes with several useful utilities, which I'll describe shortly. + +To get started, create a virtual environment and install the package. + +``` +$ mkdir pyramid_todo +$ cd pyramid_todo +$ pipenv install --python 3.6 +$ pipenv shell +(pyramid-someHash) $ pipenv install pyramid +``` + +As with Flask, it's smart to create a `setup.py` file to make the app you build an easily installable Python distribution. + +``` +# setup.py +from setuptools import setup, find_packages + +requires = [ +    'pyramid', +    'paster_pastedeploy', +    'pyramid-ipython', +    'waitress' +] + +setup( +    name='pyramid_todo', +    version='0.0', +    description='A To-Do List build with Pyramid', +    author='', +    author_email='', +    keywords='web pyramid pylons', +    packages=find_packages(), +    include_package_data=True, +    install_requires=requires, +    entry_points={ +        'paste.app_factory': [ +            'main = todo:main', +        ] +    } +) +``` + +`entry_points` section near the end sets up entry points into the application that other services can use. This allows the `plaster_pastedeploy` package to access what will be the `main` function in the application for building an application object and serving it. (I'll circle back to this in a bit.) + +Thesection near the end sets up entry points into the application that other services can use. This allows thepackage to access what will be thefunction in the application for building an application object and serving it. (I'll circle back to this in a bit.) + +When you installed `pyramid`, you also gained a few Pyramid-specific shell commands; the main ones to pay attention to are `pserve` and `pshell`. `pserve` will take an INI-style configuration file specified as an argument and serve the application locally. `pshell` will also take a configuration file as an argument, but instead of serving the application, it'll open up a Python shell that is aware of the application and its internal configuration. + +The configuration file is pretty important, so it's worth a closer look. Pyramid can take its configuration from environment variables or a configuration file. To avoid too much confusion around what is where, in this tutorial you'll write most of your configuration in the configuration file, with only a select few, sensitive configuration parameters set in the virtual environment. + +Create a file called `config.ini` + +``` +[app:main] +use = egg:todo +pyramid.default_locale_name = en + +[server:main] +use = egg:waitress#main +listen = localhost:6543 +``` + +This says a couple of things: + + * The actual application will come from the `main` function located in the `todo` package installed in the environment + * To serve this app, use the `waitress` package installed in the environment and serve on localhost port 6543 + + + +When serving an application and working in development, it helps to set up logging so you can see what's going on. The following configuration will handle logging for the application: + +``` +# continuing on... +[loggers] +keys = root, todo + +[handlers] +keys = console + +[formatters] +keys = generic + +[logger_root] +level = INFO +handlers = console + +[logger_todo] +level = DEBUG +handlers = +qualname = todo + +[handler_console] +class = StreamHandler +args = (sys.stderr,) +level = NOTSET +formatter = generic + +[formatter_generic] +format = %(asctime)s %(levelname)-5.5s [%(name)s:%(lineno)s][%(threadName)s] %(message)s +``` + +In short, this configuration asks to log everything to do with the application to the console. If you want less output, set the logging level to `WARN` so a message will fire only if there's a problem. + +Because Pyramid is meant for an application that grows, plan out a file structure that could support that growth. Web applications can, of course, be built however you want. In general, the conceptual blocks you'll want to cover will contain: + + * **Models** for containing the code and logic for dealing with data representations + * **Views** for code and logic pertaining to the request-response cycle + * **Routes** for the paths for access to the functionality of your application + * **Scripts** for any code that might be used in configuration or management of the application itself + + + +Given the above, the file structure can look like so: + +``` +setup.py +config.ini +todo/ +    __init__.py +    models.py +    routes.py +    views.py +    scripts/ +``` + +Much like Flask's `app` object, Pyramid has its own central configuration. It comes from its `config` module and is known as the `Configurator` object. This object will handle everything from route configuration to pointing to where models and views exist. All this is done in an inner directory called `todo` within an `__init__.py` file. + +``` +# todo/__init__.py + +from pyramid.config import Configurator + +def main(global_config, **settings): +    """Returns a Pyramid WSGI application.""" +    config = Configurator(settings=settings) +    config.scan() +    return config.make_wsgi_app() +``` + +The `main` function looks for some global configuration from your environment as well as any settings that came through the particular configuration file you provide when you run the application. It takes those settings and uses them to build an instance of the `Configurator` object, which (for all intents and purposes) is the factory for your application. Finally, `config.scan()` looks for any views you'd like to attach to your application that are marked as Pyramid views. + +Wow, that was a lot to configure. + +### Using routes and views + +Now that a chunk of the configuration is done, you can start adding functionality to the application. Functionality comes in the form of URL routes that external clients can hit, which then map to functions that Python can run. + +With Pyramid, all functionality must be added to the `Configurator` in some way, shape, or form. For example, say you want to build the same simple `hello_world` view that you built with Flask, mapping to the route of `/`. With Pyramid, you can register the `/` route with the `Configurator` using the `.add_route()` method. This method takes as arguments the name of the route that you want to add as well as the actual pattern that must be matched to access that route. For this case, add the following to your `Configurator`: + +``` +config.add_route('home', '/') +``` + +Until you create a view and attach it to that route, that path into your application sits open and alone. When you add the view, make sure to include the `request` object in the parameter list. Every Pyramid view must have the `request` object as its first parameter, as that's what's being passed as the first argument to the view when it's called by Pyramid. + +One similarity that Pyramid views share with Flask is that you can mark a function as a view with a decorator. Specifically, the `@view_config` decorator from `pyramid.view`. + +In `views.py`, build the view that you want to see in the world. + +``` +from pyramid.view import view_config + +@view_config(route_name="hello", renderer="string") +def hello_world(request): +    """Print 'Hello, world!' as the response body.""" +    return 'Hello, world!' +``` + +With the `@view_config` decorator, you have to at least specify the name of the route that will map to this particular view. You can stack `view_config` decorators on top of one another to map to multiple routes if you want, but you have to have at least one to connect view the view at all, and each one must include the name of a route. **[NOTE: Is "to connect view the view" phrased correctly?]** + +The other argument, `renderer`, is optional but not really. If you don't specify a renderer, you have to deliberately construct the HTTP response you want to send back to the client using the `Response` object from `pyramid.response`. By specifying the `renderer` as a string, Pyramid knows to take whatever is returned by this function and wrap it in that same `Response` object with the MIME type of `text/plain`. By default, Pyramid allows you to use `string` and `json` as renderers. If you've attached a templating engine to your application because you want to have Pyramid generate your HTML as well, you can point directly to your HTML template as your renderer. + +The first view is done. Here's what `__init__.py` looks like now with the attached route. + +``` +# in __init__.py +from pyramid.config import Configurator + +def main(global_config, **settings): +    """Returns a Pyramid WSGI application.""" +    config = Configurator(settings=settings) +    config.add_route('hello', '/') +    config.scan() +    return config.make_wsgi_app() +``` + +Spectacular! Getting here was no easy feat, but now that you're set up, you can add functionality with significantly less difficulty. + +### Smoothing a rough edge + +Right now the application only has one route, but it's easy to see that a large application can have many dozens or even hundreds of routes. Containing them all in the same `main` function with your central configuration isn't really the best idea, because it would become cluttered. Thankfully, it's fairly easy to include routes with a few tweaks to the application. + +**One** : In the `routes.py` file, create a function called `includeme` (yes, it must actually be named this) that takes a configurator object as an argument. + +``` +# in routes.py +def includeme(config): +    """Include these routes within the application.""" +``` + +**Two** : Move the `config.add_route` method call from `__init__.py` into the `includeme` function: + +``` +def includeme(config): +    """Include these routes within the application.""" +    config.add_route('hello', '/') +``` + +**Three** : Alert the Configurator that you need to include this `routes.py` file as part of its configuration. Because it's in the same directory as `__init__.py`, you can get away with specifying the import path to this file as `.routes`. + +``` +# in __init__.py +from pyramid.config import Configurator + +def main(global_config, **settings): +    """Returns a Pyramid WSGI application.""" +    config = Configurator(settings=settings) +    config.include('.routes') +    config.scan() +    return config.make_wsgi_app() +``` + +### Connecting the database + +As with Flask, you'll want to persist data by connecting a database. Pyramid will leverage [SQLAlchemy][6] directly instead of using a specially tailored package. + +First get the easy part out of the way. `psycopg2` and `sqlalchemy` are required to talk to the Postgres database and manage the models, so add them to `setup.py`. + +``` +# in setup.py +requires = [ +    'pyramid', +    'pyramid-ipython', +    'waitress', +    'sqlalchemy', +    'psycopg2' +] +# blah blah other code +``` + +Now, you have a decision to make about how you'll include the database's URL. There's no wrong answer here; what you do will depend on the application you're building and how public your codebase needs to be. + +The first option will keep as much configuration in one place as possible by hard-coding the database URL into the `config.ini` file. One drawback is this creates a security risk for applications with a public codebase. Anyone who can view the codebase will be able to see the full database URL, including username, password, database name, and port. Another is maintainability; if you needed to change environments or the application's database location, you'd have to modify the `config.ini` file directly. Either that or you'll have to maintain one configuration file for each new environment, which adds the potential for discontinuity and errors in the application. **If you choose this option** , modify the `config.ini` file under the `[app:main]` heading to include this key-value pair: + +``` +sqlalchemy.url = postgres://localhost:5432/pyramid_todo +``` + +The second option specifies the location of the database URL when you create the `Configurator`, pointing to an environment variable whose value can be set depending on the environment where you're working. One drawback is that you're further splintering the configuration, with some in the `config.ini` file and some directly in the Python codebase. Another drawback is that when you need to use the database URL anywhere else in the application (e.g., in a database management script), you have to code in a second reference to that same environment variable (or set up the variable in one place and import from that location). **If you choose this option** , add the following: + +``` +# in __init__.py +import os +from pyramid.config import Configurator + +SQLALCHEMY_URL = os.environ.get('DATABASE_URL', '') + +def main(global_config, **settings): +    """Returns a Pyramid WSGI application.""" +    settings['sqlalchemy.url'] = SQLALCHEMY_URL # <-- important! +    config = Configurator(settings=settings) +    config.include('.routes') +    config.scan() +    return config.make_wsgi_app() +``` + +### Defining objects + +OK, so now you have a database. Now you need `Task` and `User` objects. + +Because it uses SQLAlchemy directly, Pyramid differs somewhat from Flash on how objects are built. First, every object you want to construct must inherit from SQLAlchemy's [declarative base class][7]. It'll keep track of everything that inherits from it, enabling simpler management of the database. + +``` +# in models.py +from sqlalchemy.ext.declarative import declarative_base + +Base = declarative_base() + +class Task(Base): +    pass + +class User(Base): +    pass +``` + +The columns, data types for those columns, and model relationships will be declared in much the same way as with Flask, although they'll be imported directly from SQLAlchemy instead of some pre-constructed `db` object. Everything else is the same. + +``` +# in models.py +from datetime import datetime +import secrets + +from sqlalchemy import ( +    Column, Unicode, Integer, DateTime, Boolean, relationship +) +from sqlalchemy.ext.declarative import declarative_base + +Base = declarative_base() + +class Task(Base): +    """Tasks for the To Do list.""" +    id = Column(Integer, primary_key=True) +    name = Column(Unicode, nullable=False) +    note = Column(Unicode) +    creation_date = Column(DateTime, nullable=False) +    due_date = Column(DateTime) +    completed = Column(Boolean, default=False) +    user_id = Column(Integer, ForeignKey('user.id'), nullable=False) +    user = relationship("user", back_populates="tasks") + +    def __init__(self, *args, **kwargs): +        """On construction, set date of creation.""" +        super().__init__(*args, **kwargs) +        self.creation_date = datetime.now() + +class User(Base): +    """The User object that owns tasks.""" +    id = Column(Integer, primary_key=True) +    username = Column(Unicode, nullable=False) +    email = Column(Unicode, nullable=False) +    password = Column(Unicode, nullable=False) +    date_joined = Column(DateTime, nullable=False) +    token = Column(Unicode, nullable=False) +    tasks = relationship("Task", back_populates="user") + +    def __init__(self, *args, **kwargs): +        """On construction, set date of creation.""" +        super().__init__(*args, **kwargs) +        self.date_joined = datetime.now() +        self.token = secrets.token_urlsafe(64) +``` + +Note that there's no `config.include` line for `models.py` anywhere because it's not needed. A `config.include` line is needed only if some part of the application's configuration needs to be changed. This has only created two objects, inheriting from some `Base` class that SQLAlchemy gave us. + +### Initializing the database + +Now that the models are done, you can write a script to talk to and initialize the database. In the `scripts` directory, create two files: `__init__.py` and `initializedb.py`. The first is simply to turn the `scripts` directory into a Python package. The second is the script needed for database management. + +`initializedb.py` needs a function to set up the necessary tables in the database. Like with Flask, this script must be aware of the `Base` object, whose metadata keeps track of every class that inherits from it. The database URL is required to point to and modify its tables. + +As such, this database initialization script will work: + +``` +# initializedb.py +from sqlalchemy import engine_from_config +from todo import SQLALCHEMY_URL +from todo.models import Base + +def main(): +    settings = {'sqlalchemy.url': SQLALCHEMY_URL} +    engine = engine_from_config(settings, prefix='sqlalchemy.') +    if bool(os.environ.get('DEBUG', '')): +        Base.metadata.drop_all(engine) +    Base.metadata.create_all(engine) +``` + +**Important note:** This will work only if you include the database URL as an environment variable in `todo/__init__.py` (the second option above). If the database URL was stored in the configuration file, you'll have to include a few lines to read that file. It will look something like this: + +``` +# alternate initializedb.py +from pyramid.paster import get_appsettings +from pyramid.scripts.common import parse_vars +from sqlalchemy import engine_from_config +import sys +from todo.models import Base + +def main(): +    config_uri = sys.argv[1] +    options = parse_vars(sys.argv[2:]) +    settings = get_appsettings(config_uri, options=options) +    engine = engine_from_config(settings, prefix='sqlalchemy.') +    if bool(os.environ.get('DEBUG', '')): +        Base.metadata.drop_all(engine) +    Base.metadata.create_all(engine) +``` + +Either way, in `setup.py`, add a console script that will access and run this function. + +``` +# bottom of setup.py +setup( +    # ... other stuff +    entry_points={ +        'paste.app_factory': [ +            'main = todo:main', +        ], +        'console_scripts': [ +            'initdb = todo.scripts.initializedb:main', +        ], +    } +) +``` + +When this package is installed, you'll have access to a new console script called `initdb`, which will construct the tables in your database. If the database URL is stored in the configuration file, you'll have to include the path to that file when you invoke the command. It'll look like `$ initdb /path/to/config.ini`. + +### Handling requests and the database + +Ok, here's where it gets a little deep. Let's talk about **transactions**. A "transaction," in an abstract sense, is any change made to an existing database. As with Flask, transactions are persisted no sooner than when they are committed. If changes have been made that haven't yet been committed, and you don't want those to occur (maybe there's an error thrown in the process), you can **rollback** a transaction and abort those changes. + +In Python, the [transaction package][8] allows you to interact with transactions as objects, which can roll together multiple changes into one single commit. `transaction` provides **transaction managers** , which give applications a straightforward, thread-aware way of handling transactions so all you need to think about is what to change. The `pyramid_tm` package will take the transaction manager from `transaction` and wire it up in a way that's appropriate for Pyramid's request-response cycle, attaching a transaction manager to every incoming request. + +Normally, with Pyramid the `request` object is populated when the route mapping to a view is accessed and the view function is called. Every view function will have a `request` object to work with**.** However, Pyramid allows you to modify its configuration to add whatever you might need to the `request` object. You can use the transaction manager that you'll be adding to the `request` to create a session with every request and add that session to the request. + +Yay, so why is this important? + +By attaching a transaction-managed session to the `request` object, when the view finishes processing the request, any changes made to the database session will be committed without you needing to explicitly commit**.** Here's what all these concepts look like in code. + +``` +# __init__.py +import os +from pyramid.config import Configurator +from sqlalchemy import engine_from_config +from sqlalchemy.orm import sessionmaker +import zope.sqlalchemy + +SQLALCHEMY_URL = os.environ.get('DATABASE_URL', '') + +def get_session_factory(engine): +    """Return a generator of database session objects.""" +    factory = sessionmaker() +    factory.configure(bind=engine) +    return factory + +def get_tm_session(session_factory, transaction_manager): +    """Build a session and register it as a transaction-managed session.""" +    dbsession = session_factory() +    zope.sqlalchemy.register(dbsession, transaction_manager=transaction_manager) +    return dbsession + +def main(global_config, **settings): +    """Returns a Pyramid WSGI application.""" +    settings['sqlalchemy.url'] = SQLALCHEMY_URL +    settings['tm.manager_hook'] = 'pyramid_tm.explicit_manager' +    config = Configurator(settings=settings) +    config.include('.routes') +    config.include('pyramid_tm') +    session_factory = get_session_factory(engine_from_config(settings, prefix='sqlalchemy.')) +    config.registry['dbsession_factory'] = session_factory +    config.add_request_method( +        lambda request: get_tm_session(session_factory, request.tm), +        'dbsession', +        reify=True +    ) + +    config.scan() +    return config.make_wsgi_app() +``` + +That looks like a lot, but it only did was what was explained above, plus it added an attribute to the `request` object called `request.dbsession`. + +A few new packages were included here, so update `setup.py` with those packages. + +``` +# in setup.py +requires = [ +    'pyramid', +    'pyramid-ipython', +    'waitress', +    'sqlalchemy', +    'psycopg2', +    'pyramid_tm', +    'transaction', +    'zope.sqlalchemy' +] +# blah blah other stuff +``` + +### Revisiting routes and views + +You need to make some real views that handle the data within the database and the routes that map to them. + +Start with the routes. You created the `routes.py` file to handle your routes but didn't do much beyond the basic `/` route. Let's fix that. + +``` +# routes.py +def includeme(config): +    config.add_route('info', '/api/v1/') +    config.add_route('register', '/api/v1/accounts') +    config.add_route('profile_detail', '/api/v1/accounts/{username}') +    config.add_route('login', '/api/v1/accounts/login') +    config.add_route('logout', '/api/v1/accounts/logout') +    config.add_route('tasks', '/api/v1/accounts/{username}/tasks') +    config.add_route('task_detail', '/api/v1/accounts/{username}/tasks/{id}') +``` + +Now, it not only has static URLs like `/api/v1/accounts`, but it can handle some variable URLs like `/api/v1/accounts/{username}/tasks/{id}` where any variable in a URL will be surrounded by curly braces. + +To create the view to create an individual task in your application (like in the Flash example), you can use the `@view_config` decorator to ensure that it only takes incoming `POST` requests and check out how Pyramid handles data from the client. + +Take a look at the code, then check out how it differs from Flask's version. + +``` +# in views.py +from datetime import datetime +from pyramid.view import view_config +from todo.models import Task, User + +INCOMING_DATE_FMT = '%d/%m/%Y %H:%M:%S' + +@view_config(route_name="tasks", request_method="POST", renderer='json') +def create_task(request): +    """Create a task for one user.""" +    response = request.response +    response.headers.extend({'Content-Type': 'application/json'}) +    user = request.dbsession.query(User).filter_by(username=request.matchdict['username']).first() +    if user: +        due_date = request.json['due_date'] +        task = Task( +            name=request.json['name'], +            note=request.json['note'], +            due_date=datetime.strptime(due_date, INCOMING_DATE_FMT) if due_date else None, +            completed=bool(request.json['completed']), +            user_id=user.id +        ) +        request.dbsession.add(task) +        response.status_code = 201 +        return {'msg': 'posted'} +``` + +To start, note on the `@view_config` decorator that the only type of request you want this view to handle is a "POST" request. If you want to specify one type of request or one set of requests, provide either the string noting the request or a tuple/list of such strings. + +``` +response = request.response +response.headers.extend({'Content-Type': 'application/json'}) +# ...other code... +response.status_code = 201 +``` + +The HTTP response sent to the client is generated based on `request.response`. Normally, you wouldn't have to worry about that object. It would just produce a properly formatted HTTP response and you'd never know the difference. However, because you want to do something specific, like modify the response's status code and headers, you need to access that response and its methods/attributes. + +Unlike with Flask, you don't need to modify the view function parameter list just because you have variables in the route URL. Instead, any time a variable exists in the route URL, it is collected in the `matchdict` attribute of the `request`. It will exist there as a key-value pair, where the key will be the variable (e.g., "username") and the value will be whatever value was specified in the route (e.g., "bobdobson"). Regardless of what value is passed in through the route URL, it'll always show up as a string in the `matchdict`. So, when you want to pull the username from the incoming request URL, access it with `request.matchdict['username']` + +``` +user = request.dbsession.query(User).filter_by(username=request.matchdict['username']).first() +``` + +Querying for objects when using `sqlalchemy` directly differs significantly from what the `flask-sqlalchemy` package allows. Recall that when you used `flask-sqlalchemy` to build your models, the models inherited from the `db.Model` object. That `db` object already contained a connection to the database, so that connection could perform a straightforward operation like `User.query.all()`. + +That simple interface isn't present here, as the models in the Pyramid app inherit from `Base`, which is generated from `declarative_base()`, coming directly from the `sqlalchemy` package. It has no direct awareness of the database it'll be accessing. That awareness was attached to the `request` object via the app's central configuration as the `dbsession` attribute. Here's the code from above that did that: + +``` +config.add_request_method( +    lambda request: get_tm_session(session_factory, request.tm), +    'dbsession', +    reify=True +) +``` + +With all that said, whenever you want to query OR modify the database, you must work through `request.dbsession`. In the case, you want to query your "users" table for a specific user by using their username as their identifier. As such, the `User` object is provided as an argument to the `.query` method, then the normal SQLAlchemy operations are done from there. + +An interesting thing about this way of querying the database is that you can query for more than just one object or list of one type of object. You can query for: + + * Object attributes on their own, e.g., `request.dbsession.query(User.username)` would query for usernames + * Tuples of object attributes, e.g., `request.dbsession.query(User.username, User.date_joined)` + * Tuples of multiple objects, e.g., `request.dbsession.query(User, Task)` + + + +The data sent along with the incoming request will be found within the `request.json` dictionary. + +The last major difference is, because of all the machinations necessary to attach the committing of a session's activity to Pyramid's request-response cycle, you don't have to call `request.dbsession.commit()` at the end of your view. It's convenient, but there is one thing to be aware of moving forward. If instead of a new add to the database, you wanted to edit a pre-existing object in the database, you couldn't use `request.dbsession.commit()`. Pyramid will throw an error, saying something along the lines of "commit behavior is being handled by the transaction manager, so you can't call it on your own." And if you don't do something that resembles committing your changes, your changes won't stick. + +The solution here is to use `request.dbsession.flush()`. The job of `.flush()` is to signal to the database that some changes have been made and need to be included with the next commit. + +### Planning for the future + +At this point, you've set up most of the important parts of Pyramid, analogous to what you constructed with Flask in part one. There's much more that goes into an application, but much of the meat is handled here. Other view functions will follow similar formatting, and of course, there's always the question of security (which Pyramid has built in!). + +One of the major differences I see in the setup of a Pyramid application is that it has a much more intense configuration step than there is with Flask. I broke down those configuration steps to explain more about what's going on when a Pyramid application is constructed. However, it'd be disingenuous to act like I've known all of this since I started programming. My first experience with the Pyramid framework was with Pyramid 1.7 and its scaffolding system of `pcreate`, which builds out most of the necessary configuration, so all you need to do is think about the functionality you want to build. + +As of Pyramid 1.8, `pcreate` has been deprecated in favor of [cookiecutter][9], which effectively does the same thing. The difference is that it's maintained by someone else, and there are cookiecutter templates for more than just Pyramid projects. Now that we've gone through the components of a Pyramid project, I'd never endorse building a Pyramid project from scratch again when a cookiecutter template is available. Why do the hard work if you don't have to? In fact, the [pyramid-cookiecutter-alchemy][10] template would accomplish much of what I've written here (and a little bit more). It's actually similar to the `pcreate` scaffold I used when I first learned Pyramid. + +Learn more Python at [PyCon Cleveland 2018][11]. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/5/pyramid-framework + +作者：[Nicholas Hunt-Walker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/nhuntwalker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/18/4/flask +[2]: http://flask.pocoo.org/ +[3]: https://trypyramid.com/ +[4]: http://www.tornadoweb.org/en/stable/ +[5]: https://www.djangoproject.com/ +[6]: https://www.sqlalchemy.org/ +[7]: http://docs.sqlalchemy.org/en/latest/orm/extensions/declarative/api.html#api-reference +[8]: http://zodb.readthedocs.io/en/latest/transactions.html +[9]: https://cookiecutter.readthedocs.io/en/latest/ +[10]: https://github.com/Pylons/pyramid-cookiecutter-alchemy +[11]: https://us.pycon.org/2018/ diff --git a/sources/tech/20180518 How to Manage Fonts in Linux.md b/sources/tech/20180518 How to Manage Fonts in Linux.md deleted file mode 100644 index 0faca7fa17..0000000000 --- a/sources/tech/20180518 How to Manage Fonts in Linux.md +++ /dev/null @@ -1,145 +0,0 @@ -How to Manage Fonts in Linux -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/fonts_main.jpg?itok=qcJks7-c) - -Not only do I write technical documentation, I write novels. And because I’m comfortable with tools like GIMP, I also create my own book covers (and do graphic design for a few clients). That artistic endeavor depends upon a lot of pieces falling into place, including fonts. - -Although font rendering has come a long way over the past few years, it continues to be an issue in Linux. If you compare the look of the same fonts on Linux vs. macOS, the difference is stark. This is especially true when you’re staring at a screen all day. But even though the rendering of fonts has yet to find perfection in Linux, one thing that the open source platform does well is allow users to easily manage their fonts. From selecting, adding, scaling, and adjusting, you can work with fonts fairly easily in Linux. - -Here, I’ll share some of the tips I’ve depended on over the years to help extend my “font-ability” in Linux. These tips will especially help those who undertake artistic endeavors on the open source platform. Because there are so many desktop interfaces available for Linux (each of which deal with fonts in a different way), when a desktop environment becomes central to the management of fonts, I’ll be focusing primarily on GNOME and KDE. - -With that said, let’s get to work. - -### Adding new fonts - -For the longest time, I have been a collector of fonts. Some might say I have a bit of an obsession. And since my early days of using Linux, I’ve always used the same process for adding fonts to my desktops. There are two ways to do this: - - * Make the fonts available on a per-user basis. - - * Make the fonts available system-wide. - - - - -Because my desktops never have other users (besides myself), I only ever work with fonts on a per-user basis. However, I will show you how to do both. First, let’s see how to add fonts on a per-user basis. The first thing you must do is find fonts. Both True Type Fonts (TTF) and Open Type Fonts (OTF) can be added. I add fonts manually. Do this is, I create a new hidden directory in ~/ called ~/.fonts. This can be done with the command: -``` -mkdir ~/.fonts - -``` - -With that folder created, I then move all of my TTF and OTF files into the directory. That’s it. Every font you add into that directory will now be available for use to your installed apps. But remember, those fonts will only be available to that one user. - -If you want to make that collection of fonts available to all, here’s what you do: - - 1. Open up a terminal window. - - 2. Change into the directory housing all of your fonts. - - 3. Copy all of those fonts with the commands sudo cp *.ttf *.TTF /usr/share/fonts/truetype/ and sudo cp *.otf *.OTF /usr/share/fonts/opentype - - - - -The next time a user logs in, they’ll have access to all those glorious fonts. - -### GUI Font Managers - -There are a few ways to manage your fonts in Linux, via GUI. How it’s done will depend on your desktop environment. Let’s examine KDE first. With the KDE that ships with Kubuntu 18.04, you’ll find a Font Management tool pre-installed. Open that tool and you can easily add, remove, enable, and disable fonts (as well as get information about all of the installed fonts. This tool also makes it easy for you to add and remove fonts for personal and system-wide use. Let’s say you want to add a particular font for personal usage. To do this, download your font and then open up the Font Management tool. In this tool (Figure 1), click on Personal Fonts and then click the + Add button. - - -![adding fonts][2] - -Figure 1: Adding personal fonts in KDE. - -[Used with permission][3] - -Navigate to the location of your fonts, select them, and click Open. Your fonts will then be added to the Personal section and are immediately available for you to use (Figure 2). - - -![KDE Font Manager][5] - -Figure 2: Fonts added with the KDE Font Manager. - -[Used with permission][3] - -To do the same thing in GNOME requires the installation of an application. Open up either GNOME Software or Ubuntu Software (depending upon the distribution you’re using) and search for Font Manager. Select Font Manager and then click the Install button. Once the software is installed, launch it from the desktop menu. With the tool open, let’s install fonts on a per-user basis. Here’s how: - - 1. Select User from the left pane (Figure 3). - - 2. Click the + button at the top of the window. - - 3. Navigate to and select the downloaded fonts. - - 4. Click Open. - - - - -![Adding fonts ][7] - -Figure 3: Adding fonts in GNOME. - -[Used with permission][3] - -### Tweaking fonts - -There are three concepts you must first understand: - - * **Font Hinting:** The use of mathematical instructions to adjust the display of a font outline so that it lines up with a rasterized grid. - - * **Anti-aliasing:** The technique used to add greater realism to a digital image by smoothing jagged edges on curved lines and diagonals. - - * **Scaling factor:** **** A scalable unit that allows you to multiple the point size of a font. So if you’re font is 12pt and you have an scaling factor of 1, the font size will be 12pt. If your scaling factor is 2, the font size will be 24pt. - - - - -Let’s say you’ve installed your fonts, but they don’t look quite as good as you’d like. How do you tweak the appearance of fonts? In both the KDE and GNOME desktops, you can make a few adjustments. One thing to consider with the tweaking of fonts is that taste is very much subjective. You might find yourself having to continually tweak until you get the fonts looking exactly how you like (dictated by your needs and particular taste). Let’s first look at KDE. - -Open up the System Settings tool and clock on Fonts. In this section, you can not only change various fonts, you can also enable and configure both anti-aliasing and enable font scaling factor (Figure 4). - - -![Configuring fonts][9] - -Figure 4: Configuring fonts in KDE. - -[Used with permission][3] - -To configure anti-aliasing, select Enabled from the drop-down and then click Configure. In the resulting window (Figure 5), you can configure an exclude range, sub-pixel rendering type, and hinting style. - -Once you’ve made your changes, click Apply. Restart any running applications and the new settings will take effect. - -To do this in GNOME, you have to have either use Font Manager or GNOME Tweaks installed. For this, GNOME Tweaks is the better tool. If you open the GNOME Dash and cannot find Tweaks installed, open GNOME Software (or Ubuntu Software), and install GNOME Tweaks. Once installed, open it and click on the Fonts section. Here you can configure hinting, anti-aliasing, and scaling factor (Figure 6). - -![Tweaking fonts][11] - -Figure 6: Tweaking fonts in GNOME. - -[Used with permission][3] - -### Make your fonts beautiful - -And that’s the gist of making your fonts look as beautiful as possible in Linux. You may not see a macOS-like rendering of fonts, but you can certainly improve the look. Finally, the fonts you choose will have a large impact on how things look. Make sure you’re installing clean, well-designed fonts; otherwise, you’re fighting a losing battle. - -Learn more about Linux through the free ["Introduction to Linux" ][12] course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/learn/intro-to-linux/2018/5/how-manage-fonts-linux - -作者：[Jack Wallen][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/jlwallen -[2]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/fonts_1.jpg?itok=7yTTe6o3 (adding fonts) -[3]:https://www.linux.com/licenses/category/used-permission -[5]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/fonts_2.jpg?itok=_g0dyVYq (KDE Font Manager) -[7]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/fonts_3.jpg?itok=8o884QKs (Adding fonts ) -[9]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/fonts_4.jpg?itok=QJpPzFED (Configuring fonts) -[11]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/fonts_6.jpg?itok=4cQeIW9C (Tweaking fonts) -[12]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20180523 How to dual-boot Linux and Windows.md b/sources/tech/20180523 How to dual-boot Linux and Windows.md deleted file mode 100644 index 372097c866..0000000000 --- a/sources/tech/20180523 How to dual-boot Linux and Windows.md +++ /dev/null @@ -1,224 +0,0 @@ -translating by Auk7F7 -How to dual-boot Linux and Windows -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/migration_innovation_computer_software.png?itok=VCFLtd0q) - -Even though Linux is a great operating system with widespread hardware and software support, the reality is that sometimes you have to use Windows, perhaps due to key apps that won't run under Linux. Thankfully, dual-booting Windows and Linux is very straightforward—and I'll show you how to set it up, with Windows 10 and Ubuntu 18.04, in this article. - -Before you get started, make sure you've backed up your computer. Although the dual-boot setup process is not very involved, accidents can still happen. So take the time to back up your important files in case chaos theory comes into play. In addition to backing up your files, consider taking an image backup of the disk as well, though that's not required and can be a more advanced process. - -### Prerequisites - -To get started, you will need the following five items: - -#### 1\. Two USB flash drives (or DVD-Rs) - -I recommend installing Windows and Ubuntu via flash drives since they're faster than DVDs. It probably goes without saying, but creating bootable media erases everything on the flash drive. Therefore, make sure the flash drives are empty or contain data you don't care about losing. - -If your machine doesn't support booting from USB, you can create DVD media instead. Unfortunately, because no two computers seem to have the same DVD-burning software, I can't walk you through that process. However, if your DVD-burning application has an option to burn from an ISO image, that's the option you need. - -#### 2\. A Windows 10 license - -If Windows 10 came with your PC, the license will be built into the computer, so you don't need to worry about entering it during installation. If you bought the retail edition, you should have a product key, which you will need to enter during the installation process. - -#### 3\. Windows 10 Media Creation Tool - -Download and launch the Windows 10 [Media Creation Tool][1]. Once you launch the tool, it will walk you through the steps required to create the Windows media on a USB or DVD-R. Note: Even if you already have Windows 10 installed, it's a good idea to create bootable media anyway, just in case something goes wrong and you need to reinstall it. - -#### 4\. Ubuntu 18.04 installation media - -Download the [Ubuntu 18.04][2] ISO image. - -#### 5\. Etcher software (for making a bootable Ubuntu USB drive) - -For creating bootable media for any Linux distribution, I recommend [Etcher][3]. Etcher works on all three major operating systems (Linux, MacOS, and Windows) and is careful not to let you overwrite your current operating system partition. - -Once you have downloaded and launched Etcher, click Select image, and point it to the Ubuntu ISO you downloaded in step 4. Next, click Select drive to choose your flash drive, and click Flash! to start the process of turning a flash drive into an Ubuntu installer. (If you're using a DVD-R, use your computer's DVD-burning software instead.) - -### Install Windows and Ubuntu - -You should be ready to begin. At this point, you should have accomplished the following: - - * Backed up your important files - * Created Windows installation media - * Created Ubuntu installation media - - - -There are two ways of going about the installation. First, if you already have Windows 10 installed, you can have the Ubuntu installer resize the partition, and the installation will proceed in the empty space. Or, if you haven't installed Windows 10, install it on a smaller partition you can set up during the installation process. (I'll describe how to do that below.) The second way is preferred and less error-prone. There's a good chance you won't have any issues either way, but installing Windows manually and giving it a smaller partition, then installing Ubuntu, is the easiest way to go. - -If you already have Windows 10 on your computer, skip the following Windows installation instructions and proceed to Installing Ubuntu. - -#### Installing Windows - -Insert the Windows installation media you created into your computer and boot from it. How you do this depends on your computer, but most have a key you can press to initiate the boot menu. On a Dell PC for example, that key is F12. If the flash drive doesn't show up as an option, you may need to restart the computer. Sometimes it will show up only if you've inserted the media before turning on the computer. If you see a message like, "press any key to boot from the installation media," press a key. You should see the following screen. Select your language and keyboard style and click Next. - -![Windows setup][5] - -Click on Install now to start the Windows installer. - -On the next screen, it will ask for your product key. If you don't have one because Windows 10 came with your PC, select "I don't have a product key." It should automatically activate after the installation once it catches up with updates. If you do have a product key, type that in and click Next. - - -![Enter product key][7] - - -Select which version of Windows you want to install. If you have a retail copy, the label will tell you what version you have. Otherwise, it is typically located with the documentation that came with your computer. In most cases, it's going to be either Windows 10 Home or Windows 10 Pro. Most PCs that come with the Home edition have a label that simply reads "Windows 10," while Pro is clearly marked. - - -![Select Windows version][10] - - -Accept the license agreement by checking the box, then click Next. - - -![Accept license terms][12] - - -After accepting the agreement, you have two installation options available. Choose the second option, Custom: Install Windows only (advanced). - - -![Select type of Windows installation][14] - - -The next screen should show your current hard disk configuration. - - -![Hard drive configuration][16] - - -Your results will probably look different than mine. I have never used this hard disk before, so it's completely unallocated. You will probably see one or more partitions for your current operating system. Highlight each partition and remove it. - -At this point, your screen will show your entire disk as unallocated. To continue, create a new partition. - - -![Create a new partition][18] - - -Here you can see that I divided the drive in half (or close enough) by creating a partition of 81,920MB (which is close to half of 160GB). Give Windows at least 40GB, preferably 64GB or more. Leave the rest of the drive unallocated, as that's where you'll install Ubuntu later. - -Your results will look similar to this: - - -![Leaving a partition with unallocated space][20] - - -Confirm the partitioning looks good to you and click Next. Windows will begin installing. - - -![Installing Windows][22] - - -If your computer successfully boots into Windows, you're all set to move on to the next step. - -![Windows desktop][24] - - -#### Installing Ubuntu - -Whether it was already there or you worked through the steps above, at this point you should have Windows installed. Now use the Ubuntu installation media you created earlier to boot into Ubuntu. Go ahead and insert the media and boot your computer from it. Again, the exact sequence of keys to access the boot menu varies from one computer to another, so check your documentation if you're not sure. If all goes well, you see the following screen once the media finishes loading: - - -![Ubuntu installation welcome screen][26] - - -Here, you can select between Try Ubuntu or Install Ubuntu. Don't install just yet; instead, click Try Ubuntu. After it finishes loading, you should see the Ubuntu desktop. - - -![Ubuntu desktop][28] - -By clicking Try Ubuntu, you have opted to try out Ubuntu before you install it. Here, in Live mode, you can play around with Ubuntu and make sure everything works before you commit to the installation. Ubuntu works with most PC hardware, but it's always better to test it out beforehand. Make sure you can access the internet and get audio and video playback. Going to YouTube and playing a video is a good way of doing all of that at once. If you need to connect to a wireless network, click on the networking icon at the top-right of the screen. There, you can find a list of wireless networks and connect to yours. - -Once you're ready to go, double-click on the Install Ubuntu 18.04 LTS icon on the desktop to launch the installer. - -Choose the language you want to use for the installation process, then click Continue. - - -![Select language in Ubuntu][30] - - -Next, choose the keyboard layout. Once you've made your selection, click Continue. - - -![Select keyboard in Ubuntu][32] - -You have a few options on the screen below. One, you can choose a Normal or a Minimal installation. For most people, the Normal installation is ideal. Advanced users may want to do a Minimal install instead, which has fewer software applications installed by default. In addition, you can choose to download updates and whether or not to include third-party software and drivers. I recommend checking both of those boxes. When done, click Continue. - - -![Choose Ubuntu installation options][34] - -The next screen asks whether you want to erase the disk or set up a dual-boot. Since you're dual-booting, choose Install Ubuntu alongside Windows 10. Click Install Now. - - -![install Ubuntu alongside Windows][36] - - -The following screen may appear. If you installed Windows from scratch and left unallocated space on the disk, Ubuntu will automatically set itself up in the empty space, so you won't see this screen. If you already had Windows 10 installed and it's taking up the entire drive, this screen will appear and give you an option to select a disk at the top. If you have just one disk, you can choose how much space to steal from Windows and apply to Ubuntu. You can drag the vertical line in the middle left and right with your mouse to take space away from one and gives it to the other. Adjust this exactly the way you want it, then click Install Now. - - -![Allocate drive space][38] - - -You should see a confirmation screen indicating what Ubuntu plans on doing. If everything looks right, click Continue. - -Ubuntu is now installing in the background. You still have some configuration to do, though. While Ubuntu tries its best to figure out your location, you can click on the map to narrow it down to ensure your time zone and other things are set correctly. - -Next, fill in the user account information: your name, computer name, username, and password. Click Continue when you're done. - -There you have it! The installation is complete. Go ahead and reboot the PC. - -If all went according to plan, you should see a screen similar to this when your computer restarts. Choose Ubuntu or Windows 10; the other options are for troubleshooting, so I won't go into them. - -Try booting into both Ubuntu and Windows to test them out and make sure everything works as expected. If it does, you now have both Windows and Ubuntu installed on your computer. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/5/dual-boot-linux - -作者：[Jay LaCroix][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/jlacroix -[1]:https://www.microsoft.com/en-us/software-download/windows10 -[2]:https://www.ubuntu.com/download/desktop -[3]:http://www.etcher.io -[4]:/file/397066 -[5]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_01.png (Windows setup) -[6]:/file/397076 -[7]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_03.png (Enter product key) -[8]:data:image/gif;base64,R0lGODlhAQABAPABAP///wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw== (Click and drag to move) -[9]:/file/397081 -[10]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_04.png (Select Windows version) -[11]:/file/397086 -[12]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_05.png (Accept license terms) -[13]:/file/397091 -[14]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_06.png (Select type of Windows installation) -[15]:/file/397096 -[16]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_07.png (Hard drive configuration) -[17]:/file/397101 -[18]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_08.png (Create a new partition) -[19]:/file/397106 -[20]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_09.png (Leaving a partition with unallocated space) -[21]:/file/397111 -[22]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_10.png (Installing Windows) -[23]:/file/397116 -[24]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_11.png (Windows desktop) -[25]:/file/397121 -[26]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_12.png (Ubuntu installation welcome screen) -[27]:/file/397126 -[28]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_13.png (Ubuntu desktop) -[29]:/file/397131 -[30]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_15.png (Select language in Ubuntu) -[31]:/file/397136 -[32]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_16.png (Select keyboard in Ubuntu) -[33]:/file/397141 -[34]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_17.png (Choose Ubuntu installation options) -[35]:/file/397146 -[36]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_18.png (Install Ubuntu alongside Windows) -[37]:/file/397151 -[38]:https://opensource.com/sites/default/files/uploads/linux-dual-boot_18b.png (Allocate drive space) diff --git a/sources/tech/20180525 How to Set Different Wallpaper for Each Monitor in Linux.md b/sources/tech/20180525 How to Set Different Wallpaper for Each Monitor in Linux.md deleted file mode 100644 index 386149400c..0000000000 --- a/sources/tech/20180525 How to Set Different Wallpaper for Each Monitor in Linux.md +++ /dev/null @@ -1,89 +0,0 @@ -How to Set Different Wallpaper for Each Monitor in Linux -====== -**Brief: If you want to display different wallpapers on multiple monitors on Ubuntu 18.04 or any other Linux distribution with GNOME, MATE or Budgie desktop environment, this nifty tool will help you achieve this.** - -Multi-monitor setup often leads to multiple issues on Linux but I am not going to discuss those issues in this article. I have rather a positive article on multiple monitor support on Linux. - -If you are using multiple monitor, perhaps you would like to setup a different wallpaper for each monitor. I am not sure about other Linux distributions and desktop environments, but Ubuntu with [GNOME desktop][1] doesn’t provide this functionality on its own. - -Fret not! In this quick tutorial, I’ll show you how to set a different wallpaper for each monitor on Linux distributions with GNOME desktop environment. - -### Setting up different wallpaper for each monitor on Ubuntu 18.04 and other Linux distributions - -![Different wallaper on each monitor in Ubuntu][2] - -I am going to use a nifty tool called [HydraPaper][3] for setting different backgrounds on different monitors. HydraPaper is a [GTK][4] based application to set different backgrounds for each monitor in [GNOME desktop environment][5]. - -It also supports on [MATE][6] and [Budgie][7] desktop environments. Which means Ubuntu MATE and [Ubuntu Budgie][8] users can also benefit from this application. - -#### Install HydraPaper on Linux using FlatPak - -HydraPaper can be installed easily using [FlatPak][9]. Ubuntu 18.04 already provides support for FlatPaks so all you need to do is to download the application file and double click on it to open it with the GNOME Software Center. - -You can refer to this article to learn [how to enable FlatPak support][10] on your distribution. Once you have the FlatPak support enabled, just download it from [FlatHub][11] and install it. - -[Download HydraPaper][12] - -#### Using HydraPaper for setting different background on different monitors - -Once installed, just look for HydraPaper in application menu and start the application. You’ll see images from your Pictures folder here because by default the application takes images from the Pictures folder of the user. - -You can add your own folder(s) where you keep your wallpapers. Do note that it doesn’t find images recursively. If you have nested folders, it will only show images from the top folder. - -![Setting up different wallpaper for each monitor on Linux][13] - -Using HydraPaper is absolutely simple. Just select the wallpapers for each monitor and click on the apply button at the top. You can easily identify external monitor(s) termed with HDMI. - -![Setting up different wallpaper for each monitor on Linux][14] - -You can also add selected wallpapers to ‘Favorites’ for quick access. Doing this will move the ‘favorite wallpapers’ from Wallpapers tab to Favorites tab. - -![Setting up different wallpaper for each monitor on Linux][15] - -You don’t need to start HydraPaper at each boot. Once you set different wallpaper for different monitor, the settings are saved and you’ll see your chosen wallpapers even after restart. This would be expected behavior of course but I thought I would mention the obvious. - -One big downside of HydraPaper is in the way it is designed to work. You see, HydraPaper combines your selected wallpapers into one single image and stretches it across the screens giving an impression of having different background on each display. And this becomes an issue when you remove the external display. - -For example, when I tried using my laptop without the external display, it showed me an background image like this. - -![Dual Monitor wallpaper HydraPaper][16] - -Quite obviously, this is not what I would expect. - -#### Did you like it? - -HydraPaper makes setting up different backgrounds on different monitors a painless task. It supports more than two monitors and monitors with different orientation. Simple interface with only the required features makes it an ideal application for those who always use dual monitors. - -How do you set different wallpaper for different monitor on Linux? Do you think HydraPaper is an application worth installing? - -Do share your views and if you find this article, please share it on various social media channels such as Twitter and [Reddit][17]. - --------------------------------------------------------------------------------- - -via: https://itsfoss.com/wallpaper-multi-monitor/ - -作者：[Abhishek Prakash][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://itsfoss.com/author/abhishek/ -[1]:https://www.gnome.org/ -[2]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/05/multi-monitor-wallpaper-setup-800x450.jpeg -[3]:https://github.com/GabMus/HydraPaper -[4]:https://www.gtk.org/ -[5]:https://itsfoss.com/gnome-tricks-ubuntu/ -[6]:https://mate-desktop.org/ -[7]:https://budgie-desktop.org/home/ -[8]:https://itsfoss.com/ubuntu-budgie-18-review/ -[9]:https://flatpak.org -[10]:https://flatpak.org/setup/ -[11]:https://flathub.org -[12]:https://flathub.org/apps/details/org.gabmus.hydrapaper -[13]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/05/different-wallpaper-each-monitor-hydrapaper-2-800x631.jpeg -[14]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/05/different-wallpaper-each-monitor-hydrapaper-1.jpeg -[15]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/05/different-wallpaper-each-monitor-hydrapaper-3.jpeg -[16]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/05/hydra-paper-dual-monitor-800x450.jpeg -[17]:https://www.reddit.com/r/LinuxUsersGroup/ diff --git a/sources/tech/20180527 Streaming Australian TV Channels to a Raspberry Pi.md b/sources/tech/20180527 Streaming Australian TV Channels to a Raspberry Pi.md new file mode 100644 index 0000000000..ac756223f1 --- /dev/null +++ b/sources/tech/20180527 Streaming Australian TV Channels to a Raspberry Pi.md @@ -0,0 +1,209 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Streaming Australian TV Channels to a Raspberry Pi) +[#]: via: (https://blog.dxmtechsupport.com.au/streaming-australian-tv-channels-to-a-raspberry-pi/) +[#]: author: (James Mawson https://blog.dxmtechsupport.com.au/author/james-mawson/) + +Streaming Australian TV Channels to a Raspberry Pi +====== + +If you’re anything like me, it’s been years since you’ve even thought about hooking an antenna to your television. With so much of the good stuff available by streaming and download, it’s easy go a very long time without even thinking about free-to-air TV. + +But every now and again, something comes up – perhaps the cricket, news and current affairs shows, the FIFA World Cup – where the easiest thing would be to just chuck on the telly. + +When I first started tinkering with the Raspberry Pi as a gaming and media centre platform, the standard advice for watching broadcast TV always seemed to involve an antenna and a USB TV tuner. + +Which I guess is fine if you can be arsed. + +But what if you utterly can’t? + +What if you bitterly resent the idea of more clutter, more cords to add to the mess, more stuff to buy? What if every USB port is precious and jealously guarded for your keyboard, mouse, game controllers and removable storage? What if the wall port for your roof antenna is in a different room? + +That’s all a bit of a hassle for a thing you might use only a few times a year. + +In 2018, shouldn’t we just be able to stream free TV from the internet? + +It turns out that, yes, we can access legal and high quality TV streams from any Australian IP using [Freeview][1]. And thanks to a cool Kodi Add-on by [Matt Huisman][2], it’s now really easy to access this service from a Raspberry Pi. + +I’ve tested this to work on a Model 3 B+ running Retropie 4.4 and Kodi 17.6. But it should work similarly for other models and operating systems, so long as you’re using a reasonably up-to-date version of Kodi. + +Let’s jump right in. + +### If You Already Have Kodi Installed + +If you’re already using your Raspberry Pi to watch movies and TV shows, there’s a good chance you’ve already installed Kodi. + +Most Raspberry Pi operating systems intended for media centre use – such as OSMC or Xbian – come with Kodi installed by default. + +It’s fairly easy to get running on other Linux operating systems, and you might have already installed it there too. + +If your version of Kodi is more than a year or so old, it might be an idea to update it. The following instructions are written for the interface on Kodi 17 (Krypton). + +You can do that by typing the following commands at the command line: + +``` +sudo apt-get update +sudo apt-get upgrade +``` + +And now you can skip ahead to the next section. + +### Installing Kodi + +Installing Kodi on Retropie and other versions of Raspbian is fairly simple. Other Linux operating systems should be able to run it, perhaps with a bit of coaxing. + +You will need to be connected to the internet to install it. + +If you’re using something, such as Risc OS – you probably can’t install kodi. You will need to either swap in another SD card, or use a boot loader to boot into a media centre OS for your TV viewing. + +#### Installing Kodi on Retropie + +It’s really easy to install Kodi using the Retropie menu system. + +Here’s how: + + 1. Navigate to the Retropie main screen – that’s that horizontal menu where you can scroll left and right through all your different consoles + 2. Select “Retropie” + 3. Select “Retropie setup” + 4. Select “Manage Packages” + 5. Select “Manage Optional Packages” + 6. Scroll down and select “Kodi” + 7. Select “Install from Binary” + + + +This will take a minute or two to install. Once it’s installed, you can exit out of the Retropie Setup screen. When you next restart Retropie, you will see Kodi under the “Ports” section of the Retropie main screen. + +#### Installing Kodi on Raspbian + +If you’re running Raspbian without Retropie. But that’s okay, because it’s pretty easy to do it from the command line + +Just type: + +``` +sudo apt-get update +sudo apt-get install kodi +``` + +At this point you have a vanilla installation of Kodi. You can run it by typing: + +``` +kodi +``` + +It’s possible to delve a lot further into setting up Kodi from the command line. Check out [this guide][3] if you’re interested. + +If not, what you’ve just installed will work just fine. + +#### Installing Kodi on Other Versions of Linux + +If you’re using a different flavour of Linux, such as Pidora or Arch Linux ARM, then the above might or might not work – I’m not really sure, because I don’t really use these operating systems. + +If you get stuck, it might be worth a look at the [how-to guide][4] on the Kodi wiki. + +#### Dual Booting a Media Centre OS + +If your operating system of choice isn’t suitable for Kodi – or is just too confusing and difficult to figure out – it might be easiest to use a boot loader for multiple operating systems on the one SD card. + +You can set this up using an OS installer like [PINN][5]. + +Using PINN, you can install a media centre OS like [OSMC][6] to use Kodi – it will be installed with the operating system – and then your preferred OS for your other uses. + +It’s even possible to [move your existing OS over][7]. + +### Adding Australian TV Channels to Kodi + +With Kodi installed and running, you’ve got a pretty good media player for the files on your network and hard drive. + +But we need to install an add-on if we want to use it to chuck on the telly. This only takes a minute or so. + +#### Installing Matt Huisman’s Kodi Repository + +Ready? Let’s get started. + + 1. Open Kodi + 2. Click the cog icon at the top left to enter the settings + 3. Click “System Settings” + 4. Select “Add-ons” + 5. Make sure that “Unknown Sources” is enabled + 6. Right click anywhere on the screen to navigate back to the settings menu + 7. Click “File Manager” + 8. Click “Add Source” + 9. Double-click “Add Source” + 10. Select “” + 11. Type in exactly **** + 12. Select “OK” + 13. Click the text input underneath the label “Enter a name for this media source.” + 14. Type in exactly **MJH** + 15. Click “OK” + 16. Right click twice anywhere on the screen to navigate back to the main menu + 17. Select “Add-ons” + 18. Click “My Add-ons” + 19. Click “..” + 20. Click “Install from zip file” + 21. Click “MJH” + 22. Select “repository.matthuisman.zip” + + + +The repository is now installing. + +If you get stuck with any of this, here’s a video from Matt that starts by installing the repository. + + + +#### Installing the Freeview Australia Add-On + +We’re nearly there! Just a few more steps. + + 1. Right click anywhere on the screen a couple of times to navigate back to the main menu + 2. Select “Add-ons” + 3. Click “My add-ons” + 4. Click “..” + 5. Click “Install from repository” + 6. Click “MattHuisman.nz Repository” + 7. Click “Video add-ons” + 8. Click “AU Freeview” + 9. Click “Install” + + + +You can now have every free-to-air TV channel in your Add-ons main menu item. + +### Watching TV + +When you want to chuck the telly on, all you need to do is click “AU Freeview” in the Add-ons main menu item. This will give you a list of channels to browse through and select. + +If you want, you can also add individual channels to your Favourites menu by right clicking them and selecting “Add to favourites”. + +By default you will be watching Melbourne television. You can change the region by right clicking on “AU Freeview” and clicking “settings”. + +When you first tune in, it sometimes jumps a bit for a few seconds, but after that it’s pretty smooth. + +After spending a few minutes with this, you’ll quickly realise that free-to-air TV hasn’t improved in the years since you last looked at. Unfortunately, I don’t think there’s a fix for that. + +But at least it’s there now for when you want it. + +-------------------------------------------------------------------------------- + +via: https://blog.dxmtechsupport.com.au/streaming-australian-tv-channels-to-a-raspberry-pi/ + +作者：[James Mawson][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://blog.dxmtechsupport.com.au/author/james-mawson/ +[b]: https://github.com/lujun9972 +[1]: http://www.freeview.com.au/ +[2]: https://www.matthuisman.nz/ +[3]: https://www.raspberrypi.org/forums/viewtopic.php?t=192499 +[4]: https://kodi.wiki/view/HOW-TO:Install_Kodi_for_Linux +[5]: https://github.com/procount/pinn +[6]: https://osmc.tv/ +[7]: https://github.com/procount/pinn/wiki/How-to-Create-a-Multi-Boot-SD-card-out-of-2-existing-OSes-using-PINN diff --git a/sources/tech/20180604 4 Firefox extensions worth checking out.md b/sources/tech/20180604 4 Firefox extensions worth checking out.md index 2091afe6fe..2e6a22274b 100644 --- a/sources/tech/20180604 4 Firefox extensions worth checking out.md +++ b/sources/tech/20180604 4 Firefox extensions worth checking out.md @@ -1,3 +1,4 @@ +translated by lixinyuxx 4 Firefox extensions worth checking out ====== diff --git a/sources/tech/20180614 An introduction to the Tornado Python web app framework.md b/sources/tech/20180614 An introduction to the Tornado Python web app framework.md new file mode 100644 index 0000000000..9c9e5c9500 --- /dev/null +++ b/sources/tech/20180614 An introduction to the Tornado Python web app framework.md @@ -0,0 +1,590 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (An introduction to the Tornado Python web app framework) +[#]: via: (https://opensource.com/article/18/6/tornado-framework) +[#]: author: (Nicholas Hunt-Walker https://opensource.com/users/nhuntwalker) +[#]: url: ( ) + +An introduction to the Tornado Python web app framework +====== +In the third part in a series comparing Python frameworks, learn about Tornado, built to handle asynchronous processes. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/tornado.png?itok=kAa3eXIU) + +In the first two articles in this four-part series comparing different Python web frameworks, we've covered the [Pyramid][1] and [Flask][2] web frameworks. We've built the same app twice and seen the similarities and differences between a complete DIY framework and a framework with a few more batteries included. + +Now let's look at a somewhat different option: [the Tornado framework][3]. Tornado is, for the most part, as bare-bones as Flask, but with a major difference: Tornado is built specifically to handle asynchronous processes. That special sauce isn't terribly useful in the app we're building in this series, but we'll see where we can use it and how it works in a more general situation. + +Let's continue the pattern we set in the first two articles and start by tackling the setup and config. + +### Tornado startup and configuration + +If you've been following along with this series, what we do first shouldn't come as much of a surprise. + +``` +$ mkdir tornado_todo +$ cd tornado_todo +$ pipenv install --python 3.6 +$ pipenv shell +(tornado-someHash) $ pipenv install tornado +``` + +Create a `setup.py` for installing our application: + +``` +(tornado-someHash) $ touch setup.py +# setup.py +from setuptools import setup, find_packages + +requires = [ +    'tornado', +    'tornado-sqlalchemy', +    'psycopg2', +] + +setup( +    name='tornado_todo', +    version='0.0', +    description='A To-Do List built with Tornado', +    author='', +    author_email='', +    keywords='web tornado', +    packages=find_packages(), +    install_requires=requires, +    entry_points={ +        'console_scripts': [ +            'serve_app = todo:main', +        ], +    }, +) +``` + +Because Tornado doesn't require any external configuration, we can dive right into writing the Python code that'll run our application. Let's make our inner `todo` directory and fill it with the first few files we'll need. + +``` +todo/ +    __init__.py +    models.py +    views.py +``` + +Like Flask and Pyramid, Tornado has some central configuration that will go in `__init__.py`. From `tornado.web`, we'll import the `Application` object. This will handle the hookups for routing and views, including our database (when we get there) and any extra settings needed to run our Tornado app. + +``` +# __init__.py +from tornado.httpserver import HTTPServer +from tornado.options import define, options +from tornado.web import Application + +define('port', default=8888, help='port to listen on') + +def main(): +    """Construct and serve the tornado application.""" +    app = Application() +    http_server = HTTPServer(app) +    http_server.listen(options.port) +``` + +When we use the `define` function, we end up creating attributes on the `options` object. Anything that goes in the position of the first argument will be the attribute's name, and what's assigned to the `default` keyword argument will be the value of that attribute. + +As an example, if we name the attribute `potato` instead of `port`, we can access its value via `options.potato`. + +Calling `listen` on the `HTTPServer` doesn't start the server yet. We must do one more step to have a working application that can listen for requests and return responses. We need an input-output loop. Thankfully, Tornado comes with that out of the box in the form of `tornado.ioloop.IOLoop`. + +``` +# __init__.py +from tornado.httpserver import HTTPServer +from tornado.ioloop import IOLoop +from tornado.options import define, options +from tornado.web import Application + +define('port', default=8888, help='port to listen on') + +def main(): +    """Construct and serve the tornado application.""" +    app = Application() +    http_server = HTTPServer(app) +    http_server.listen(options.port) +    print('Listening on http://localhost:%i' % options.port) +    IOLoop.current().start() +``` + +I like some kind of a `print` statement somewhere that tells me when I'm serving my application, but that's me. You could do without the `print` line if you so chose. + +We begin our I/O loop with `IOLoop.current().start()`. Let's talk a little more about input, output, and asynchronicity. + +### The basics of async in Python and the I/O loop + +Allow me to preface by saying that I am absolutely, positively, surely, and securely not an expert in asynchronous programming. As with all things I write, what follows stems from the limits of my understanding of the concept. As I am human, it may be deeply, deeply flawed. + +The main concerns of an asynchronous program are: + + * How is data coming in? + * How is data going out? + * When can some procedure be left to run without consuming my full attention? + + + +Due to the [global interpreter lock][4] (GIL), Python is—by design—a [single-threaded][5] language. For every task a Python program must execute, the full attention of its thread of execution is on that task for the duration of that task. Our HTTP server is written in Python. Thus, when data (e.g., an HTTP request) is received, the server's sole focus is that incoming data. This means that, in most cases, whatever procedures need to run in handling and processing that data will completely consume your server's thread of execution, blocking other potential data from being received until your server finishes whatever it needed to do. + +In many cases this isn't too problematic; a typical web request-response cycle will take only fractions of a second. Along with that, the sockets that HTTP servers are built from can maintain a backlog of incoming requests to be handled. So, if a request comes in while that socket is handling something else, chances are it'll just wait in line a bit before being addressed. For a low to intermediate traffic site, a fraction of a second isn't that big of a deal, and you can use multiple deployed instances along with a load-balancer like [NGINX][6] to distribute traffic for the larger request loads. + +What if, however, your average response time takes more than a fraction of a second? What if you use data from the incoming request to start some long-running process like a machine-learning algorithm or some massive database query? Now, your single-threaded web server starts to accumulate an unaddressable backlog of requests, some of which will get dropped due to simply timing out. This is not an option, especially if you want your service to be seen as reliable on a regular basis. + +In comes the asynchronous Python program. It's important to keep in mind that because it's written in Python, the program is still a single-threaded process. Anything that would block execution in a synchronous program, unless specifically flagged, will still block execution in an asynchronous one. + +When it's structured correctly, however, your asynchronous Python program can "shelve" long-running tasks whenever you designate that a certain function should have the ability to do so. Your async controller can then be alerted when the shelved tasks are complete and ready to resume, managing their execution only when needed without completely blocking the handling of new input. + +That was somewhat jargony, so let's demonstrate with a human example. + +#### Bringing it home + +I often find myself trying to get multiple chores done at home with little time to do them. On a given day, that backlog of chores may look like: + + * Cook a meal (20 min. prep, 40 min. cook) + * Wash dishes (60 min.) + * Wash and dry laundry (30 min. wash, 90 min. dry per load) + * Vacuum floors (30 min.) + + + +If I were acting as a traditional, synchronous program, I'd be doing each task myself, by hand. Each task would require my full attention to complete before I could consider handling anything else, as nothing would get done without my active attention. So my sequence of execution might look like: + + 1. Focus fully on preparing and cooking the meal, including waiting around for food to just… cook (60 min.). + 2. Transfer dirty dishes to sink (65 min. elapsed). + 3. Wash all the dishes (125 min. elapsed). + 4. Start laundry with my full focus on that, including waiting around for the washing machine to finish, then transferring laundry to the dryer, and waiting for the dryer to finish (250 min. elapsed). + 5. Vacuum the floors (280 min. elapsed). + + + +That's 4 hours and 40 minutes to complete my chores from end-to-end. + +Instead of working hard, I should work smart like an asynchronous program. My home is full of machines that can do my work for me without my continuous effort. Meanwhile, I can switch my attention to what may actively need it right now. + +My execution sequence might instead look like: + + 1. Load clothes into and start the washing machine (5 min.). + 2. While the washing machine is running, prep food (25 min. elapsed). + 3. After prepping food, start cooking food (30 min. elapsed). + 4. While the food is cooking, move clothes from the washing machine into the dryer and start dryer (35 min. elapsed). + 5. While dryer is running and food is still cooking, vacuum the floors (65 min. elapsed). + 6. After vacuuming the floors, take food off the stove and load the dishwasher (70 min. elapsed). + 7. Run the dishwasher (130 min. when done). + + + +Now I'm down to 2 hours and 10 minutes. Even if I allow more time for switching between jobs (10-20 more minutes total), I'm still down to about half the time I would've spent if I'd waited to perform each task in sequential order. This is the power of structuring your program to be asynchronous. + +#### So where does the I/O loop come in? + +An asynchronous Python program works by taking in data from some external source (input) and, should the process require it, offloading that data to some external worker (output) for processing. When that external process finishes, the main Python program is alerted. The program then picks up the result of that external processing (input) and continues on its merry way. + +Whenever that data isn't actively in the hands of the main Python program, that main program is freed to work on just about anything else. This includes awaiting completely new inputs (e.g., HTTP requests) and handling the results of long-running processes (e.g., results of machine-learning algorithms, long-running database queries). The main program, while still single-threaded, becomes event-driven, triggered into action for specific occurrences handled by the program. The main worker that listens for those events and dictates how they should be handled is the I/O loop. + +We traveled a long road to get to this nugget of an explanation, I know, but what I'm hoping to communicate here is that it's not magic, nor is it some type of complex parallel processing or multi-threaded work. The global interpreter lock is still in place; any long-running process within the main program will still block anything else from happening. The program is also still single-threaded; however, by externalizing tedious work, we conserve the attention of that thread to only what it needs to be attentive to. + +This is kind of like my asynchronous chores above. When my attention is fully necessary for prepping food, that's all I'm doing. However, when I can get the stove to do work for me by cooking my food, and the dishwasher to wash my dishes, and the washing machine and dryer to handle my laundry, my attention is freed to work on other things. When I am alerted that one of my long-running tasks is finished and ready to be handled once again, if my attention is free, I can pick up the results of that task and do whatever needs to be done with it next. + +### Tornado routes and views + +Despite having gone through all the trouble of talking about async in Python, we're going to hold off on using it for a bit and first write a basic Tornado view. + +Unlike the function-based views we've seen in the Flask and Pyramid implementations, Tornado's views are all class-based. This means we'll no longer use individual, standalone functions to dictate how requests are handled. Instead, the incoming HTTP request will be caught and assigned to be an attribute of our defined class. Its methods will then handle the corresponding request types. + +Let's start with a basic view that prints "Hello, World" to the screen. Every class-based view we construct for our Tornado app must inherit from the `RequestHandler` object found in `tornado.web`. This will set up all the ground-level logic that we'll need (but don't want to write) to take in a request and construct a properly formatted HTTP response. + +``` +from tornado.web import RequestHandler + +class HelloWorld(RequestHandler): +    """Print 'Hello, world!' as the response body.""" + +    def get(self): +        """Handle a GET request for saying Hello World!.""" +        self.write("Hello, world!") +``` + +Because we're looking to handle a `GET` request, we declare (really override) the `get` method. Instead of returning anything, we provide text or a JSON-serializable object to be written to the response body with `self.write`. After that, we let the `RequestHandler` take on the rest of the work that must be done before a response can be sent. + +As it stands, this view has no actual connection to the Tornado application itself. We have to go back into `__init__.py` and update the `main` function a bit. Here's the new hotness: + +``` +# __init__.py +from tornado.httpserver import HTTPServer +from tornado.ioloop import IOLoop +from tornado.options import define, options +from tornado.web import Application +from todo.views import HelloWorld + +define('port', default=8888, help='port to listen on') + +def main(): +    """Construct and serve the tornado application.""" +    app = Application([ +        ('/', HelloWorld) +    ]) +    http_server = HTTPServer(app) +    http_server.listen(options.port) +    print('Listening on http://localhost:%i' % options.port) +    IOLoop.current().start() +``` + +#### What'd we do? + +We imported the `HelloWorld` view from the `views.py` file into `__init__.py` at the top of the script. Then we added a list of route-view pairs as the first argument to the instantiation to `Application`. Whenever we want to declare a route in our application, it must be tied to a view. You can use the same view for multiple routes if you want, but there must always be a view for every route. + +We can make sure this all works by running our app with the `serve_app` command we enabled in the `setup.py`. Check `http://localhost:8888/` and see that it says "Hello, world!" + +Of course, there's more we can and will do in this space, but let's move on to models. + +### Connecting the database + +If we want to hold onto data, we need to connect a database. Like with Flask, we'll be using a framework-specific variant of SQLAlchemy called [tornado-sqlalchemy][7]. + +Why use this instead of just the bare [SQLAlchemy][8]? Well, `tornado-sqlalchemy` has all the goodness of straightforward SQLAlchemy, so we can still declare models with a common `Base` as well as use all the column data types and relationships to which we've grown accustomed. Alongside what we already know from habit, `tornado-sqlalchemy` provides an accessible async pattern for its database-querying functionality specifically to work with Tornado's existing I/O loop. + +We set the stage by adding `tornado-sqlalchemy` and `psycopg2` to `setup.py` to the list of required packages and reinstall the package. In `models.py`, we declare our models. This step looks pretty much exactly like what we've already seen in Flask and Pyramid, so I'll skip the full-class declarations and just put up the necessaries of the `Task` model. + +``` +# this is not the complete models.py, but enough to see the differences +from tornado_sqlalchemy import declarative_base + +Base = declarative_base + +class Task(Base): +    # and so on, because literally everything's the same... +``` + +We still have to connect `tornado-sqlalchemy` to the actual application. In `__init__.py`, we'll be defining the database and integrating it into the application. + +``` +# __init__.py +from tornado.httpserver import HTTPServer +from tornado.ioloop import IOLoop +from tornado.options import define, options +from tornado.web import Application +from todo.views import HelloWorld + +# add these +import os +from tornado_sqlalchemy import make_session_factory + +define('port', default=8888, help='port to listen on') +factory = make_session_factory(os.environ.get('DATABASE_URL', '')) + +def main(): +    """Construct and serve the tornado application.""" +    app = Application([ +        ('/', HelloWorld) +    ], +        session_factory=factory +    ) +    http_server = HTTPServer(app) +    http_server.listen(options.port) +    print('Listening on http://localhost:%i' % options.port) +    IOLoop.current().start() +``` + +Much like the session factory we passed around in Pyramid, we can use `make_session_factory` to take in a database URL and produce an object whose sole purpose is to provide connections to the database for our views. We then tie it into our application by passing the newly created `factory` into the `Application` object with the `session_factory` keyword argument. + +Finally, initializing and managing the database will look the same as it did for Flask and Pyramid (i.e., separate DB management script, working with respect to the `Base` object, etc.). It'll look so similar that I'm not going to reproduce it here. + +### Revisiting views + +Hello, World is always nice for learning the basics, but we need some real, application-specific views. + +Let's start with the info view. + +``` +# views.py +import json +from tornado.web import RequestHandler + +class InfoView(RequestHandler): +    """Only allow GET requests.""" +    SUPPORTED_METHODS = ["GET"] + +    def set_default_headers(self): +        """Set the default response header to be JSON.""" +        self.set_header("Content-Type", 'application/json; charset="utf-8"') + +    def get(self): +        """List of routes for this API.""" +        routes = { +            'info': 'GET /api/v1', +            'register': 'POST /api/v1/accounts', +            'single profile detail': 'GET /api/v1/accounts/', +            'edit profile': 'PUT /api/v1/accounts/', +            'delete profile': 'DELETE /api/v1/accounts/', +            'login': 'POST /api/v1/accounts/login', +            'logout': 'GET /api/v1/accounts/logout', +            "user's tasks": 'GET /api/v1/accounts//tasks', +            "create task": 'POST /api/v1/accounts//tasks', +            "task detail": 'GET /api/v1/accounts//tasks/', +            "task update": 'PUT /api/v1/accounts//tasks/', +            "delete task": 'DELETE /api/v1/accounts//tasks/' +        } +        self.write(json.dumps(routes)) +``` + +So what changed? Let's go from the top down. + +The `SUPPORTED_METHODS` class attribute was added. This will be an iterable of only the request methods that are accepted by this view. Any other method will return a [405][9] status code. When we made the `HelloWorld` view, we didn't specify this, mostly out of laziness. Without this class attribute, this view would respond to any request trying to access the route tied to the view. + +The `set_default_headers` method is declared, which sets the default headers of the outgoing HTTP response. We declare this here to ensure that any response we send back has a `"Content-Type"` of `"application/json"`. + +We added `json.dumps(some_object)` to the argument of `self.write` because it makes it easy to construct the content for the body of the outgoing response. + +Now that's done, and we can go ahead and connect it to the home route in `__init__.py`. + +``` +# __init__.py +from tornado.httpserver import HTTPServer +from tornado.ioloop import IOLoop +from tornado.options import define, options +from tornado.web import Application +from todo.views import InfoView + +# add these +import os +from tornado_sqlalchemy import make_session_factory + +define('port', default=8888, help='port to listen on') +factory = make_session_factory(os.environ.get('DATABASE_URL', '')) + +def main(): +    """Construct and serve the tornado application.""" +    app = Application([ +        ('/', InfoView) +    ], +        session_factory=factory +    ) +    http_server = HTTPServer(app) +    http_server.listen(options.port) +    print('Listening on http://localhost:%i' % options.port) +    IOLoop.current().start() +``` + +As we know, more views and routes will need to be written. Each one will get dropped into the `Application` route listing as needed. Each will also need a `set_default_headers` method. On top of that, we'll create our `send_response`method, whose job it will be to package our response along with any custom status codes we want to set for a given response. Since each one will need both methods, we can create a base class containing them that each of our views can inherit from. That way, we have to write them only once. + +``` +# views.py +import json +from tornado.web import RequestHandler + +class BaseView(RequestHandler): +    """Base view for this application.""" + +    def set_default_headers(self): +        """Set the default response header to be JSON.""" +        self.set_header("Content-Type", 'application/json; charset="utf-8"') + +    def send_response(self, data, status=200): +        """Construct and send a JSON response with appropriate status code.""" +        self.set_status(status) +        self.write(json.dumps(data)) +``` + +For a view like the `TaskListView` we'll soon write, we'll also need a connection to the database. We'll need `tornado_sqlalchemy`'s `SessionMixin` to add a database session within every view class. We can fold that into the `BaseView` so that, by default, every view inheriting from it has access to a database session. + +``` +# views.py +import json +from tornado_sqlalchemy import SessionMixin +from tornado.web import RequestHandler + +class BaseView(RequestHandler, SessionMixin): +    """Base view for this application.""" + +    def set_default_headers(self): +        """Set the default response header to be JSON.""" +        self.set_header("Content-Type", 'application/json; charset="utf-8"') + +    def send_response(self, data, status=200): +        """Construct and send a JSON response with appropriate status code.""" +        self.set_status(status) +        self.write(json.dumps(data)) +``` + +As long as we're modifying this `BaseView` object, we should address a quirk that will come up when we consider data being posted to this API. + +When Tornado (as of v.4.5) consumes data from a client and organizes it for use in the application, it keeps all the incoming data as bytestrings. However, all the code here assumes Python 3, so the only strings that we want to work with are Unicode strings. We can add another method to this `BaseView` class whose job it will be to convert the incoming data to Unicode before using it anywhere else in the view. + +If we want to convert this data before we use it in a proper view method, we can override the view class's native `prepare` method. Its job is to run before the view method runs. If we override the `prepare` method, we can set some logic to run that'll do the bytestring-to-Unicode conversion whenever a request is received. + +``` +# views.py +import json +from tornado_sqlalchemy import SessionMixin +from tornado.web import RequestHandler + +class BaseView(RequestHandler, SessionMixin): +    """Base view for this application.""" + +    def prepare(self): +        self.form_data = { +            key: [val.decode('utf8') for val in val_list] +            for key, val_list in self.request.arguments.items() +        } + +    def set_default_headers(self): +        """Set the default response header to be JSON.""" +        self.set_header("Content-Type", 'application/json; charset="utf-8"') + +    def send_response(self, data, status=200): +        """Construct and send a JSON response with appropriate status code.""" +        self.set_status(status) +        self.write(json.dumps(data)) +``` + +If there's any data coming in, it'll be found within the `self.request.arguments` dictionary. We can access that data by key and convert its contents (always a list) to Unicode. Because this is a class-based view instead of a function-based view, we can store the modified data as an instance attribute to be used later. I called it `form_data` here, but it can just as easily be called `potato`. The point is that we can store data that has been submitted to the application. + +### Asynchronous view methods + +Now that we've built our `BaseView`, we can build the `TaskListView` that will inherit from it. + +As you can probably tell from the section heading, this is where all that talk about asynchronicity comes in. The `TaskListView` will handle `GET` requests for returning a list of tasks and `POST` requests for creating new tasks given some form data. Let's first look at the code to handle the `GET` request. + +``` +# all the previous imports +import datetime +from tornado.gen import coroutine +from tornado_sqlalchemy import as_future +from todo.models import Profile, Task + +# the BaseView is above here +class TaskListView(BaseView): +    """View for reading and adding new tasks.""" +    SUPPORTED_METHODS = ("GET", "POST",) + +    @coroutine +    def get(self, username): +        """Get all tasks for an existing user.""" +        with self.make_session() as session: +            profile = yield as_future(session.query(Profile).filter(Profile.username == username).first) +            if profile: +                tasks = [task.to_dict() for task in profile.tasks] +                self.send_response({ +                    'username': profile.username, +                    'tasks': tasks +                }) +``` + +The first major piece here is the `@coroutine` decorator, imported from `tornado.gen`. Any Python callable that has a portion that acts out of sync with the normal flow of the call stack is effectively a "co-routine"; a routine that can run alongside other routines. In the example of my household chores, pretty much every chore was a co-routine. Some were blocking routines (e.g., vacuuming the floor), but that routine simply blocked my ability to start or attend to anything else. It didn't block any of the other routines that were already set in motion from continuing. + +Tornado offers a number of ways to build an app that take advantage of co-routines, including allowing us to set locks on function calls, conditions for synchronizing asynchronous routines, and a system for manually modifying the events that control the I/O loop. + +The only way the `@coroutine` decorator is used here is to allow the `get` method to farm out the SQL query as a background process and resume once the query is complete, while not blocking the Tornado I/O loop from handling other sources of incoming data. That is all that's "asynchronous" about this implementation: out-of-band database queries. Clearly if we wanted to showcase the magic and wonder of an async web app, a To-Do List isn't the way. + +But hey, that's what we're building, so let's see how our method takes advantage of that `@coroutine` decorator. The `SessionMixin` that was, well, mixed into the `BaseView` declaration added two handy, database-aware attributes to our view class: `session` and `make_session`. They're similarly named and accomplish fairly similar goals. + +The `self.session` attribute is a session with an eye on the database. At the end of the request-response cycle, just before the view sends a response back to the client, any changes that have been made to the database are committed, and the session is closed. + +`self.make_session` is a context manager and generator, building and returning a brand new session object on the fly. That first `self.session` object still exists; `make_session` creates a new one anyway. The `make_session` generator also has baked into itself the logic for committing and closing the session it creates as soon as its context (i.e., indentation level) ends. + +If you inspect the source code, there is no difference between the type of object assigned to `self.session` and the type of object generated by `self.make_session`. The difference is in how they're managed. + +With the `make_session` context manager, the generated session belongs only to the context, beginning and ending within that context. You can open, modify, commit, and close multiple database sessions within the same view with the `make_session` context manager. + +`self.session` is much simpler, with the session already opened by the time you get to your view method and committing before the response is sent back to the client. + +Although the [read the docs snippet][10] and the [the PyPI example][11] both specify the use of the context manager, there's nothing about either the `self.session` object or the `session` generated by `self.make_session` that is inherently asynchronous. The point where we start thinking about the async behavior built into `tornado-sqlalchemy` comes when we initiate a query. + +The `tornado-sqlalchemy` package provides us with the `as_future` function. The job of `as_future` is to wrap the query constructed by the `tornado-sqlalchemy` session and yield its return value. If the view method is decorated with `@coroutine`, then using this `yield as_future(query)` pattern will now make your wrapped query an asynchronous background process. The I/O loop takes over, awaiting the return value of the query and the resolution of the `future` object created by `as_future`. + +To have access to the result from `as_future(query)`, you must `yield` from it. Otherwise, you get only an unresolved generator object and can do nothing with the query. + +Everything else in this view method is pretty much par for the course, mirroring what we've already seen in Flask and Pyramid. + +The `post` method will look fairly similar. For the sake of consistency, let's see how the `post` method looks and how it handles the `self.form_data` that was constructed with the `BaseView`. + +``` +@coroutine +def post(self, username): +    """Create a new task.""" +    with self.make_session() as session: +        profile = yield as_future(session.query(Profile).filter(Profile.username == username).first) +        if profile: +            due_date = self.form_data['due_date'][0] +            task = Task( +                name=self.form_data['name'][0], +                note=self.form_data['note'][0], +                creation_date=datetime.now(), +                due_date=datetime.strptime(due_date, '%d/%m/%Y %H:%M:%S') if due_date else None, +                completed=self.form_data['completed'][0], +                profile_id=profile.id, +                profile=profile +            ) +            session.add(task) +            self.send_response({'msg': 'posted'}, status=201) +``` + +As I said, it's about what we'd expect: + + * The same query pattern as we saw with the `get` method + * The construction of an instance of a new `Task` object, populated with data from `form_data` + * The adding (but not committing because it's handled by the context manager!) of the new `Task` object to the database session + * The sending of a response back to the client + + + +And thus we have the basis for our Tornado web app. Everything else (e.g., database management and more views for a more complete app) is effectively the same as what we've already seen in the Flask and Pyramid apps. + +### Thoughts about using the right tool for the right job + +What we're starting to see as we continue to move through these web frameworks is that they can all effectively handle the same problems. For something like this To-Do List, any framework can do the job. However, some web frameworks are more appropriate for certain jobs than other ones, depending on what "more appropriate" means for you and your needs. + +While Tornado is clearly capable of handling the same job that Pyramid or Flask can handle, to use it for an app like this is effectively a waste. It's like using a car to travel one block from home. Yes it can do the job of "travel," but short trips aren't why you choose to use a car over a bike or just your feet. + +Per the documentation, Tornado is billed as "a Python web framework and asynchronous networking library." There are few like it in the Python web framework ecosystem. If the job you're trying to accomplish requires (or would benefit significantly from) asynchronicity in any way, shape, or form, use Tornado. If your application needs to handle multiple, long-lived connections while not sacrificing much in performance, choose Tornado. If your application is many applications in one and needs to be thread-aware for the accurate handling of data, reach for Tornado. That's where it works best. + +Use your car to do "car things." Use other modes of transportation to do everything else. + +### Going forward and a little perspective check + +Speaking of using the right tool for the right job, keep in mind the scope and scale, both present and future, of your application when choosing your framework. Up to this point we've only looked at frameworks meant for small to midsized web applications. The next and final installment of this series will cover one of the most popular Python frameworks, Django, meant for big applications that might grow bigger. Again, while it technically can and will handle the To-Do List problem, keep in mind that it's not really what the framework is for. We'll still put it through its paces to show how an application can be built with it, but we have to keep in mind the intent of the framework and how that's reflected in its architecture: + + * **Flask:** Meant for small, simple projects; makes it easy for us to construct views and connect them to routes quickly; can be encapsulated in a single file without much fuss + * **Pyramid:** Meant for projects that may grow; contains a fair bit of configuration to get up and running; separate realms of application components can easily be divided and built out to arbitrary depth without losing sight of the central application + * **Tornado:** Meant for projects benefiting from precise and deliberate I/O control; allows for co-routines and easily exposes methods that can control how requests are received/responses are sent and when those operations occur + * **Django:** (As we'll see) meant for big things that may get bigger; large ecosystem of add-ons and mods; very opinionated in its configuration and management in order to keep all the disparate parts in line + + + +Whether you've been reading since the first post in this series or joined a little later, thanks for reading! Please feel free to leave questions or comments. I'll see you next time with hands full of Django. + +### Huge shout-out to the Python BDFL + +I must give credit where credit is due. Massive thanks are owed to [Guido van Rossum][12] for more than just creating my favorite programming language. + +During [PyCascades 2018][13], I was fortunate not only to give the talk this article series is based on, but also to be invited to the speakers' dinner. I got to sit next to Guido the whole night and pepper him with questions. One of those questions was how in the world async worked in Python, and he, without a bit of fuss, spent time explaining it to me in a way that I could start to grasp the concept. He later [tweeted to me][14] a spectacular resource for learning async with Python that I subsequently read three times over three months, then wrote this post. You're an awesome guy, Guido! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/6/tornado-framework + +作者：[Nicholas Hunt-Walker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/nhuntwalker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/18/5/pyramid-framework +[2]: https://opensource.com/article/18/4/flask +[3]: https://tornado.readthedocs.io/en/stable/ +[4]: https://realpython.com/python-gil/ +[5]: https://en.wikipedia.org/wiki/Thread_(computing) +[6]: https://www.nginx.com/ +[7]: https://tornado-sqlalchemy.readthedocs.io/en/latest/ +[8]: https://www.sqlalchemy.org/ +[9]: https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#4xx_Client_errors +[10]: https://tornado-sqlalchemy.readthedocs.io/en/latest/#usage +[11]: https://pypi.org/project/tornado-sqlalchemy/#description +[12]: https://www.twitter.com/gvanrossum +[13]: https://www.pycascades.com +[14]: https://twitter.com/gvanrossum/status/956186585493458944 diff --git a/sources/tech/20180625 The life cycle of a software bug.md b/sources/tech/20180625 The life cycle of a software bug.md index cacceb7a15..0f45d7a355 100644 --- a/sources/tech/20180625 The life cycle of a software bug.md +++ b/sources/tech/20180625 The life cycle of a software bug.md @@ -1,3 +1,4 @@ +translated by lixinyuxx The life cycle of a software bug ====== diff --git a/sources/tech/20180626 Playing Badass Acorn Archimedes Games on a Raspberry Pi.md b/sources/tech/20180626 Playing Badass Acorn Archimedes Games on a Raspberry Pi.md new file mode 100644 index 0000000000..b1f8d97305 --- /dev/null +++ b/sources/tech/20180626 Playing Badass Acorn Archimedes Games on a Raspberry Pi.md @@ -0,0 +1,539 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Playing Badass Acorn Archimedes Games on a Raspberry Pi) +[#]: via: (https://blog.dxmtechsupport.com.au/playing-badass-acorn-archimedes-games-on-a-raspberry-pi/) +[#]: author: (James Mawson https://blog.dxmtechsupport.com.au/author/james-mawson/) + +Playing Badass Acorn Archimedes Games on a Raspberry Pi +====== + +![Cannon Fodder on the Raspberry Pi][1] + +The Acorn Archimedes was an excellent machine and years ahead of its time. + +Debuting in 1987, it featured a point and click graphic interface not so different to Windows 95, 32 bit processing, and enough 3D graphics power to portal you to a new decade. + +These days, it’s best remembered for launching the Acorn RISC Machines processor. ARM processors went on to rule the world. You almost certainly keep one in your pocket. + +What’s less well appreciated is that the Archimedes was rad for games. For a few years, it was the most powerful desktop in the world and developers were eager to show what they could do with it. + +But with such power came a great price tag. The Archimedes was never going to be in as many homes to make as many memories as Sega or Nintendo. + +But now, the Raspberry Pi’s ARM chip makes it cheap and easy to play these games on the same operating system and CPU architecture they were written for. + +Even better, the rights holders to much of this machine’s gaming catalogue have been generous enough to allow hobbyists to legally download their work for free. + +This is a cheap and easy project. In fact, if you already run a Raspberry Pi home theatre or retro gaming rig, all you really need is a spare SD card. + +### Introduction + +None of this will be on the exam, so if you already know the story of the Acorn Archimedes – or just want to get straight into gaming – feel free to skip ahead to the next section. + +But if you’re wondering what we’re even talking about, here it is: + +#### What on Earth is an Acorn Archimedes? + +Me and Acorn computers go way back. + +For the earliest part of my life that I can remember, Dad ran his business from home, writing timetabling software for schools. This was the early 80s, before the desktop computer market had been whittled down to Mac and PC. There were Amstrad CPCs, Sinclairs, Commodores, Ataris, TRSs, the list goes on. + +They all had their operating systems and ran their own software. If you wanted to port your software over to a new platform, you had to buy it. + +So, at a time when it was somewhat novel for a family to have even one computer, we had about a dozen, many of them already quite antique. There was a Microbee, an Apple IIc, an IBM XT, all sorts of stuff. + +The ones Dad liked most though were the BBC machines by [Acorn Computers][2]. He had several. There was a Model B, a Master 128 and a Master Compact. + +They were named that way because the British Broadcasting Corporation were developing a course to teach children how to program and they needed. Because of this educational focus, they’d found their way into a lot of schools – exactly the market he was selling to. + +At some point, I figured out you could play games on these things. I was straight away hooked like it was crack. All I cared about was games games games. It must have taken me several years to figure out that computers had a different use, because I can vividly recall how annoyed I was to be starting school while Dad got to stay home and play games all day. + +On my 7th birthday I got a second hand BBC Master Compact all of my own. This was probably as much to keep me away from his work computers as it was to introduce me to computing. I started learning to program in BASIC and Logo. I also played epic amounts of space shooters, 2D platformers and adventure games. + +Being obsessed with these things, I tagged along to the local BBC Users Group. This was a monthly get-together where enthusiasts would discuss what was new, bring their machines to show off what they’re doing and engage in some casual software piracy. Back before internet forums and torrents, people did this in person. + +This was where I first saw an Archimedes. I can’t really remember the exact year or the exact model – I just remember my jaw dropping to the floor at the 3D graphics and the 8 channel stereo sound. It would be about a decade before I saw anything similar on a gaming console. + + + +#### The Birth of a Legend + +Looking back, this has very good claim to be the first modern desktop computer. It was a 32-bit machine, an interface that looks more like what we use today than anything built in the 1980s, a palette of 4096 colours, and more horsepower than a lot of people knew what to do with. + +Now, don’t get me wrong: the 8-bit BBC machines were loads of fun and great for what they were – but what they were was fairly primitive. It was basically just a big box you typed commands on to make it beep and stuff. In theory it had 8 colours, but when you saw one in the wild it was usually hooked up to a monochrome screen and you didn’t feel like you were missing out on too much because of it. + +In 1984, Apple launched their Macintosh, featuring the first Graphical User Interface available on the mass market. Acorn knew they’d need a point and click graphic interface to stay in the game. And they knew the aging MOS 6502 they’d used in all their machines so far was just not going to be the CPU of the future. + +So, what to replace it with? + +The Acorn engineers looked at the available processors and found that none of them could quite do what they want. They decided to build their own – and it would be radically different. + +Up until that point, chip makers took a bit of a Swiss Army Knife approach to processor design – to compete, you added more and more useful stuff to the instruction set. + +There was a certain logic to this – hardware could be mass produced, while good software engineers were expensive. It made sense to handle as much as possible in the hardware. For device manufacturers with bills to pay, it was a real selling point. + +But this came at a cost – more and more complex instructions required more and more clock cycles to complete. Often there was a whole extra layer of processing to convert the complex machine code instructions into smaller instructions. As RAM became bigger and faster, CPUs were struggling to keep pace with the available memory bandwidth. + +Acorn turned this idea on its head, with a stripped-back approach in the great British tradition of the [de Havilland Mosquito][3]: Every instruction could be completed in a single cycle. + +While testing the prototype CPU, the engineers noticed something weird: they’d disconnected the power and yet the chip was running. What they’d built was so power-efficient that it kept running on residual power from nearby components. + +It was also 25 times faster than the 6502 CPU they used in the old BBC machines. Even better, it was several times more powerful than the Motorola 68000 found in the Apple Macintosh, Atari ST and Commodore Amiga – and several time more powerful than the 386 in the new Compaq too. + +With such radically new hardware, they needed a new operating system. What they come up with was Risc OS, and it was operated entirely through a graphic point-and-click desktop interface with a pinboard and an icon bar. This was pretty much Windows 95, 8 years before it happened. + +In a single step, Acorn had gone from producing some perfectly serviceable 8-bit box that kids could learn to code one, to having the most powerful desktop computer in the world. I mean, it was technically possible to get something more powerful – but it would have been some kind of server or mainframe. As far as something that could sit on your desk, this was top of the pile. + +It sold well in Acorn’s traditional education market in the UK. The sheer grunt also made it popular for certain power-hungry business tasks, like desktop publishing. + +#### The Crucifixion + +It wasn’t too long before Dad got an Archimedes – I can’t remember exactly which model. By this time, he’d moved his business out of home to an office. When school holidays rolled around, I’d sometimes have to spend the day at his work, where I had all the time in the world to fiddle around on it. + +The software it came with was enough to keep a child entertained for a while. It came with a demo game called Lander – this was more about showing off the machine’s 3D graphics power than providing any lasting value. There was a card game, and also some drawing programs. + + + +I played with the demo disc until I got bored – which I think was the most use that this particular machine ever got. For all the power under the hood, all the applications Dad used to actually run his business ran on DOS and Windows. + +He’d spent more than $4000 in today’s money for the most sophisticated and advanced piece of computing technology for a mile in any direction and it just sat there. + +He might have at least salvaged some beneficial utility out of it if he’d followed my advice of getting some games for it and letting me take it home. + +He never got around to writing any software on it. The Archimedes was apparently a big hit with British schools, but never really got popular enough with his Australian customer base to be worth coding for. + +Which I guess is kind of sums up where it all ultimately went wrong for the Acorn desktop. + +As the 80s wore on to the ’90s, Compaq reverse engineered the BIOS on the IBM PC to release their own fully compatible PC, and big players like Amstrad left their proprietary platforms to produce their own compatible MS-DOS machines. It was also became increasingly easy for just about anyone with a slight technical bunt to build their own PC-compatible clone from off-the-shelf parts – and to upgrade old PCs with new hard drives, sound cards, and the latest 386 and 486 processors. + +Small, independent computer shops and other local businesses started building their owns PCs and hardware manufacturers competed to sell parts to them. This was a computing platform that could serve all price points. + +With so much of the user base now on MS-DOS, software developers followed. Which only reinforced the idea that this was the obvious system to buy, which in turn reinforced that it was the system to code for. + +The days when just any computer maker could make a go of it with their own proprietary hardware and operating system had passed. Third-party support was everything. It didn’t actually matter how good your technology was if nothing would run on it. Even Apple nearly went to the wall. + +Acorn hung on through the 90s, and there was even a successor to the Archimedes called the [RiscPC][4]. But while the technology itself was again very good, these things were relatively marginal affairs in the marketplace. The era of the Acorn desktop had passed. + +#### The Resurrection + +It was definitely good for our family business when the market consolidated to Mac and PC. We didn’t need to maintain so many versions of the same software. + +But the Acorn machines had so much sentimental value. We both liked them and were sad to see them go. I’ve never been that into sport, but watching them slowly disappear might have been a bit like watching your football team lose match after match before finally going broke. + +We totally had no idea that they were, very quietly, on a path to total domination. + +The ARM was originally only built to go in the Archimedes. But it turned out that having a massively powerful processor with a simple instruction set and very little heat emission was useful for all sorts of stuff: DVD players, set top boxes, photocopiers, televisions, vending machines, home and small business routers, you name it. + +The ARM’s low power consumption made it especially useful for portable devices like PDAs, digital cameras, GPS navigators and – eventually – tablets and smartphones. Intel tried to compete in the smartphone market, but was [eventually forced to admit that this technology was just better for phones][5]. + +So in the end, Dad’s old BBC machines went on to conquer the world. + +### The Acorn Archimedes as a Gaming Platform + +While Microsoft operating systems were ultimately to become the only real choice for the serious desktop gamer, for a while the Archimedes was the most powerful desktop computer in the world. This attracted a lot of games developers, eager to show what they could do with it. + +This would have been about more than just selling to a well moneyed section of the desktop computer market that was clearly quite willing to throw cash at shiny things. It would have been a chance to make your reputation in the industry with a flagship product that just wasn’t possible on lesser hardware. + +So it is that you see Star Fighter 3000, Chocks Away and Zarch all charting new territory in what was possible on a desktop computer. + +But while the 3D graphics power was this system’s headline feature, the late 80s and early 90s were really the era of Sonic and Mario: the heyday of 2D platform games. Here, the Archimedes also excels, with offerings like Mad Professor Mariarti, Bug Hunter, F.R.E.D. and Hamsters, all of which are massively playable, have vibrant graphics and a boatload of personality. + +As you dig further into the library, you also find a few games that show that not every developer really knew what to do with this machine. Some games – like Repton 3 – are just old BBC micro games given the most meagre of facelifts. + +Many of the games in the Archimedes catalogue you’ll recognise from other platforms: Populous, Lemmings, James Pond, Battle Chess, the list goes on. + +Here, the massive hardware advantage of the Archimedes means that it usually had the best version of the game to play. You’re not getting a whole new game here: but it’s noticeably smoother graphics and gameplay, especially compared to the console releases. + +All in all, the Archimedes never had a catalogue as expansive as MS-DOS, the Commodore Amiga, or the Sega and Nintendo consoles. But there are enough truly excellent games to make it worth an SD card. + +### Configuring Your Raspberry Pi + +This is a bit different to other retro gaming options on the Raspberry Pi – we’re not running an emulator. The ARM chip in the Pi is a direct descendant of the one in the Archimedes, and there’s an [open source version of Risc OS][6] we can install on it. + +For the most hardcore retro gaming purist, nothing less than using the hardware will do. For everyone else, using the same operating system from back in the day to load up your games means that your retro gaming rig becomes just that little bit more of a time machine. + +But even with all these similarities, there’s still going to be a few things that change in 30 years of computing. + +The most visible difference is that our Raspberry Pi doesn’t come with an internal 3.5″ floppy disk drive. You might be able to hook up a USB one, but most of us don’t have this lying around and don’t really want one. So we’re going to need a different way to boot floppy images. + +The more major difference is how much RAM the operating system is written to handle. The earliest versions of Risc OS made efficient use of the ARM’s 32-bit register by using 26 bits for the memory address and the remaining 6 bits for status flags. A 26-bit scheme gives you enough addressing space for up to 64 megabytes of RAM. + +When this was first devised, the fact that an Archimedes came with a whole megabyte of RAM was considered incredibly luxurious by the standards of the day. By contrast, the first Commodore Amiga had 256kb of RAM. The Sega Mega Drive had 72kb. + +But as time wore on, and later versions of Risc OS moved to a 32-bit addressing scheme. This is what we have on our Raspberry Pi. A few games have been [recompiled to run on 32 bit addressing][7], but most have not. + +The Archimedes also used different display drivers for different screens. These days, our GPU can handle all of this for us. We just need to install a patch to get that working. + +There are free utilities you can download to handle all of these things. + +#### Hardware Requirements + +I’ve tested this to work with a Raspberry Pi Model 3 B, but I expect that any Pi from the Model A onwards should manage this. The ARM processor on the slowest Pi is a great many times more powerful than the on the fastest Archimedes. + +The lack of ports on a Raspberry Pi Zero means it’s probably not the most convenient choice, but if you can navigate around this, then it should be powerful enough. + +In addition to the board, you’ll need something to put it in, a micro SD card, a USB SD card adapter, a power supply, a screen with an HDMI input, a USB keyboard and a 3 button mouse – a clickable scroll wheel works fine for your middle button. + +If you already have a Raspberry Pi home theatre or retro gaming rig, then you’ve already got all this, so all you really need is a new micro SD card to swap in for Risc OS. + +#### Installing Risc OS Open + +When I first wrote this guide, Risc OS wasn’t an available option for the Raspberry Pi 3 on the NOOBS and PINN installers. That meant you had to download the image from the [Risc OS Open downloads page][8] and burn it to a new micro SD card. + +You can still do this if you like, and if you can’t connect your Raspberry Pi to the internet via Wi-Fi or Ethernet then that’s still your best option. If you’re not sure how to write an image to an SD card, here’s some good guides for [Windows][9] and for [Mac][10]. + +For everyone else, now that Risc OS is available in the [NOOBS installer][11] again, I recommend using that. What’s really cool about NOOBS is that it makes it super simple to dual boot with something like [Retropie][12] or [Recalbox][13] for the ultimate all-in-one retro gaming device. + +Risc OS is as an extremely good option for a dual boot machine because it only uses a few gigabytes – a small fraction of even the smallest SD cards around these days. This leaves most of it available for other operating systems and saves you having to swap cards, which can be a right pain if you have to unscrew the case. The games themselves vary from about 300kb to about 5 megabytes at the very largest, so don’t worry about that. + +This image requires a card with at least 2 gigabytes, which for what we’re doing is plenty. Don’t worry about tracking down the largest SD card you can find. The operating system is extremely lightweight and the games themselves vary from about 300kb to about 5 megabytes at the very largest. Even a very small card offers enough space for hundreds of games – more than you will ever play. + +If you’re unsure how to use the NOOBS installer, please [click here for instructions][14]. + +#### Navigating Risc OS + +Compared to your first Linux experience, using Risc OS for the first time is, in my opinion, far more gentle. This is in large part thanks to a graphical interface that’s both fairly intuitive and actually very useful for configuring things. + +The command line is there if you want it, but we won’t need it just to play some games. You can kind of tell that this was first built with a mass-market audience in mind. + +So let’s jump right in. + +Insert your card into your Pi, hook it up to your screen, keyboard, mouse and power supply. It shouldn’t take all that long before you’re at the desktop. + +###### The Risc OS Mouse + +Risc OS uses a three button mouse. + +You use the left button – or “Select” button – in much the same way as you’re already used to: one click to select icons and a double click to open folders and execute programs. + +The middle button – ie, your scroll wheel – is used to open menus in much the same way as the right mouse button is used in Windows. We’ll be using this a lot. + +The right button – or “Adjust” button – has behaviours that vary between applications. + +###### Browsing Directories + +Ok, so let’s start taking a look around. At the bottom of the screen you’ll see an icon bar. In the bottom left are icons for storage devices. + +Click once with the left mouse button on the SD card and a window will open to show you what’s on it. You can take a look inside the directories by double clicking. + +###### The Pling + +As you start to browse Risc OS, you’ll notice that a lot of what you see inside the directories has exclamation marks at the beginning. This is said out aloud as a “pling”, and it’s used to mark an application that you can execute. + +One of the quirks of Risc OS is that these executables aren’t really files – they’re directories. If you hold shift while double clicking, you can open them and start looking inside, same as any other directory – but be careful with this, it’s a good way to break stuff. + +Risc OS comes with some applications installed – including a web browser called !NetSurf. We’ll be using that soon to download our games and some small utilities we need to get them running. + +###### Creating Directories + +Risc OS comes with a basic directory structure, but you’ll probably want to create some new ones to put your floppy images and .zip files. + +To do this, click with the middle button inside the folder where you want to place your new directory. This will open up a menu. Move your mouse over the arrow next to “New Directory” and a prompt will open where you can name it and press OK. + +###### Copying Files and Directories + +To copy a file or directory somewhere else, just drag and drop it with the left mouse button to the new location. + +###### Forcing Applications to Quit + +Sometimes, if you haven’t configured something right, if you’ve downloaded something that just doesn’t work, or if you plain forgot to look up the controls in the manual, you might find yourself stuck inside an application that has a blank screen or isn’t responding. + +Here, you can press Ctrl-Shift-F12 to quit back to the desktop. + +###### Shutting Down and Rebooting + +If you want to power down or reboot your Pi, just click the middle button on the raspberry icon in the bottom right corner and select “Shutdown”. This will give you an option to reboot the Pi or you can just remove the power cable. + +#### Connecting to the Internet + +Okay, so I’ve got good news and bad news. I’ll get the bad news right out of the way first: + +Risc OS Open doesn’t yet support wireless networking through either the onboard wireless or a wireless dongle in the USB port. It’s on the [to-do list][15]. + +In the meantime, if you can a way to connect to the internet through the Ethernet port, it makes the rest of this project a lot easier. If you were going to use an Ethernet cable anyway, this will be no big deal. And if you have a wireless bridge handy, you can just use that. + +If you don’t have a wireless bridge, but do have a second Raspberry Pi board lying around (hey, who doesn’t these days :p), you can [set it up as a wireless bridge][16]. This is what I did and it’s actually pretty easy if you just follow the steps. + +Another option might be to set up a temporary tinkering area next to your router so that you can plug straight in to get everything in configured. + +Ok, so what’s the good news? + +It’s this: once you’ve got the internet in your front hole, the rest is rather easy. In fact, the only bit that’s not done for your is configuring name servers. + +So let’s get to it. + +Double-click on !Configure, click once on Network, click on Internet and then on Host Names. Then enter the IPs of your name servers in the name server fields. If you’re not sure what IP to put in here, just use Google’s publicly available name servers – 8.8.8.8 and 8.8.4.4. + +When you click Set, it will ask you if you want to reboot. Click yes. + +Now double-click on !NetSurf. You’ll see the logo is now added to the bottom right corner. Click on this to open a new browser window. + +Compared to Chrome, Firefox, et al, !NetSurf is a primitive web browser. I do not recommend it as a daily driver. But to download Risc OS software directly to the Pi, it’s actually pretty damn convenient. + +###### Short Link to This Guide + +As you go through the rest of this guide, it’s going to get annoying copying by hand all the URLs you’ll want to visit. + +To save you this trouble, type bit.do/riscpi into the browser bar to load this page. With this loaded, you can follow the links. + +###### If You’re Still Getting Host Name Error Messages + +One little quirk of Risc OS is that it seems to check for name servers as part of the boot process. If it doesn’t find them then, it assumes they’re not there for the rest of the session. + +This means that if you connect your Pi to the internet when it’s already booted, you will get an error message when you try to browse the internet with !NetSurf. + +To fix this, just double check that your wireless bridge is switched on or that your Pi is plugged into the router, reboot, and the OS should find the name servers. + +###### If You Can’t Connect to the Internet + +If this is all too hard and you absolutely can’t connect to the internet, there’s always sneakernet – downloading files to another machine and then transferring by USB stick. + +This is what I tried at first; It does work, but I found it terribly annoying. + +One frustration is that using a Windows 10 machine to download Risc OS software seems to strip out the filetype information – even when you aren’t unzipping the archives. It’s not that difficult to repair this, it’s just tedious when you have to do it all the time. + +The other problem is that running USB sticks from computer to computer all the time just got a bit old. + +Still, if you have to do it, it’s an option. + +#### Unzipping Compressed Files + +Most of the files we’ll be downloading will come in .zip format – this is a good thing, because it preserves the file type information. But we’ll need a way to uncompress these files. + +For this we’ll use a program called !SparkFS. This is proprietary software, but you can download a read-only version for free. This will let us extract files from .zip archives. + +To download and install !SparkFS, click [this link][17] and follow the instructions. You want the version of this software for machines with more than 2MB of RAM. + +#### Installing ADFFS and Anymode + +Now we need to install ADFFS, a floppy disk imaging program written by Jon Abbot of the [Archimedes Software Preservation Project][18]. + +This gives us a virtual floppy drive we can use to boot floppy images. It also takes care of the 26 bit memory addressing issues. + +To get your copy, browse to the [ADFFS subforum][19] and click the thread for the latest public release – at the time of writing that’s 2.64. + +Download the .zip file, open it and then drag and drop !ADFFS to somewhere on your SD card where it’s conveniently accessible – we’ll be using it a lot. + +###### Configuring Boot Scripts + +For ADFFS to work properly, we’re going to need to add a little boot script. + +Follow these instructions carefully – if you do the wrong thing here you can really mess up your OS, or even brick your Pi. + +###### Creating !Boot.Loader.CMDLINE/TXT + +Remember how I showed you that you could open up applications as directories by holding down shift when you double-click? We can also do this to get inside the Risc OS boot process. We’ll need to do this now to add our boot script. + +Start by left clicking once on the SD card icon on the icon bar, then hold down shift and double-click !Boot with your left mouse button. Then double click the folder labeled Loader to open it. This is where we’re going to put our script. + +To write our script, click Apps on the icon bar, then double-click !StrongEd. Now click on the fist icon that appeared on the bottom right of the icon bar to open a text editor window, and type: + +``` +disable_mode_changes +``` + +Computers are fussy so take a moment to double-check your spelling. + +To save this file, click the middle button on the text editor and hover your cursor over the arrow next to Save. Then delete the existing text in the Name field and replace it with: + +``` +CMDLINE/TXT +``` + +Now, see that button marked Save? It’s a trap! Instead, drag and drop the pen and paper icon to the Loader folder. + +We’re now finished with this folder, so you can close it and also close the text editor. + +###### Installing Anymode + +Now we need to install the Anymode module. This is to make the screen modes on our software play nice with our GPU and HDMI output. + +Download Anymode from [here,][20] copy the .zip file to somewhere temporary and open it. + +Now go back to the root directory on your SD card, double-click on !Boot again, then open the folders marked Choices, Boot and Predesk. + +Then use your left mouse button to drag and drop the Anymode module from your .zip file to the Predesk folder. + +#### Configuring USB Joysticks and Gamepads + +Over at the Archimedes Software Preservation Project, there’s a [USB joystick driver][21] in development. + +This module is still in alpha testing, and you’ll need to use the command line to configure it, but it’s there if you’d like to give it a try. + +If you can’t get this working, don’t worry too much. It was actually pretty normal back in the day for people either to not have a joystick, or not to be able to get it to work. So pretty much every game can be played with keyboard and mouse. + +I’ll be updating this section as this project develops. + +#### Setting File Types + +Risc OS uses an [ADFS][22] filesystem, different to anything used on Windows or Linux. + +Instead of using a filename extension, ADFS files have a “file type” associated with them to show what. When these files pass through a different operating system, this information can get stripped from the file. + +In theory, if we don’t open our .zip archives until it reaches our Risc OS machine, the file type should be preserved. Usually this works, but sometimes you unzip the archive and find files with no file type attached. You’ll be able to tell when this has happened because you’ll be faced with a green icon labeled “data”. + +Fortunately, this is pretty easy to fix. + +Just click on the file with your middle button. A menu will appear. + +The second item on this menu will include the name of the file and it will have an arrow next to it. Hover your cursor over the arrow and a second menu will appear. + +Near the bottom of this menu will be an option marked “Set Type”, and it will also have an arrow next to it. Hover your cursor over this arrow and a field will appear where you can enter the file type. + +To set the file type on a floppy image, type: + +``` +&FCE +``` + +[Click here for more file type codes.][23] + +### Finding, Loading and Playing Games + +The best start looking for floppy images is in the [Games subforum][24] at the Archimedes Software Preservation Project. + +There’s also a [Risc OS downloads section at Acorn Arcade][25]. + +There are definitely other websites that host Archimedes games, but I have no idea how legal these copies are. + +###### Booting and Switching Floppy Disc Images + +Some games might have specific instructions for how to boot the floppy. If so, then follow them. + +Generally, though, you drag and drop the image file to, then click on it with the middle button and press “boot floppy”. Your game should start straight away. + +Many of the games use more than one floppy disc. To play these, boot disc 1. When you’re asked to switch floppy discs, press control and shift and the function key corresponding to the disc you want to change to. + +### Which Games Should You Play? + +This is a matter of opinion really and everyone’s taste differs. + +Still, if you’re wondering what to try, here are my recommendations. + +This is still a work in progress. I’ll be adding more games as I find what I like. + +#### Cannon Fodder + + + +This is a top-down action/strategy game that’s extremely playable and wickedly funny. + +You control a team of soldiers indirectly by clicking on areas of the screen to tell them where to move and who to kill. Everyone dies with a single shot. + +At the start your enemies are all very easy to beat but the game progresses in difficulty. As you go, you’ll need to start dividing your team up into squads to command separately. + +I used to play this on the Mega Drive back in the day, but it’s so much more playable with an actual mouse. + +[Click here to get Cannon Fodder.][26] + +#### Star Fighter 3000 + + + +This is a 3D space shooter that really laid down the gauntlet for what the Archimedes could do. + +You fly around and blast stuff with lasers and missiles. It’s pretty awesome. It’s kind of a forerunner to Terminal Velocity, if you ever played that. + +It was later ported to the 3D0, Sega Saturn and Playstation, but they could never render the 3D graphics to the same distance. + +[Click here to get Star Fighter 3000.][27] + +You want the download marked “Star Fighter 3000 version 3.20”. This one doesn’t use a floppy image, so don’t use ADFFS to run this file. Just double click the program and go. + +#### Aggressor + + + +This is a side-scrolling run-and-gun where you have unlimited ammo and a whole lot of aliens and robots to kill. Badass. + +#### Bug Hunter + + + +This is a really unique puzzle/platform game – you’re a robot with sticky legs who can walk up and down walls and across the ceiling, and your job is to squash bugs by dropping objects lying around. + +Which is harder than it sounds, because you can easily get yourself into situations where you dropped something in the wrong place, making it impossible to complete your objective, so your only way out is to initiate your self destruct sequence in futility and shame. Which I guess is kinda rather dark, if you dwell on it. + +It’s fun though. + +[Click here to get Bug Hunter.][28] + +#### Mad Professor Mariarti + + + +This is a platformer where you’re a mad scientist who shoots spanners and other weapons at bad guys. It has good music and gameplay and an immersive puzzle element as well. + +[Click here to get Mad Professor Mariarti.][29] + +#### Chuckie Egg + +Ok, now we’re getting really retro. + +Strictly speaking, this doesn’t really belong in this list, because it’s not even an Archimedes game – it’s an old BBC Micro game that I played the hell out of back in the day that some nice chap has ported to Risc OS. + +But there’s a version that runs and it’s awesome so you should play it. + +Basically you’re just this guy who goes around stealing eggs. That’s it. That’s all you do. + +It’s absolutely amazing. + +If you’ve never played it, you really should check it out. + +You can [get Chuckie Egg here][30]. + +This isn’t a floppy image, so you don’t need ADFFS to run it. Just double click on the program and go. + +### Over to You + +Got any favourite Acorn Archimedes games? + +Got any tips for getting them running on the Pi? + +Please let me know in the comments section 🙂 + +-------------------------------------------------------------------------------- + +via: https://blog.dxmtechsupport.com.au/playing-badass-acorn-archimedes-games-on-a-raspberry-pi/ + +作者：[James Mawson][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://blog.dxmtechsupport.com.au/author/james-mawson/ +[b]: https://github.com/lujun9972 +[1]: https://blog.dxmtechsupport.com.au/wp-content/uploads/2018/06/cannonfodder-1024x768.jpg +[2]: http://www.computinghistory.org.uk/det/897/Acorn-Computers/ +[3]: http://davetrott.co.uk/2017/03/strategy-is-sacrifice/ +[4]: http://www.old-computers.com/museum/computer.asp?c=1015 +[5]: https://www.theverge.com/2016/8/16/12507568/intel-arm-mobile-chips-licensing-deal-idf-2016 +[6]: https://www.riscosopen.org/content/ +[7]: https://www.riscosopen.org/wiki/documentation/show/ARMv6%2Fv7%20software%20compatibility%20list#games +[8]: https://www.riscosopen.org/content/downloads/raspberry-pi +[9]: http://www.raspberry-projects.com/pi/pi-operating-systems/win32diskimager +[10]: http://osxdaily.com/2018/01/11/write-img-to-sd-card-mac-etcher/ +[11]: https://www.raspberrypi.org/downloads/noobs/ +[12]: https://retropie.org.uk/ +[13]: https://www.recalbox.com/ +[14]: https://www.raspberrypi.org/documentation/installation/noobs.md +[15]: https://www.riscosopen.org/wiki/documentation/show/RISC%20OS%20Roadmap +[16]: https://pimylifeup.com/raspberry-pi-wifi-bridge/ +[17]: http://www.riscos.com/ftp_space/generic/sparkfs/index.htm +[18]: https://forums.jaspp.org.uk/forum/index.php +[19]: https://forums.jaspp.org.uk/forum/viewforum.php?f=14&sid=d0f037e95c560144f3910503b776aef5 +[20]: http://www.pi-star.co.uk/anymode/ +[21]: https://forums.jaspp.org.uk/forum/viewtopic.php?f=8&t=396 +[22]: https://en.wikipedia.org/wiki/Advanced_Disc_Filing_System +[23]: https://www.riscosopen.org/wiki/documentation/show/File%20Types +[24]: https://forums.jaspp.org.uk/forum/viewforum.php?f=25 +[25]: http://www.acornarcade.com/downloads/ +[26]: https://forums.jaspp.org.uk/forum/viewtopic.php?f=25&t=188 +[27]: http://starfighter.acornarcade.com/ +[28]: https://forums.jaspp.org.uk/forum/viewtopic.php?f=25&t=330 +[29]: https://forums.jaspp.org.uk/forum/viewtopic.php?f=25&t=148 +[30]: http://homepages.paradise.net.nz/mjfoot/riscos.htm diff --git a/sources/tech/20180707 Version Control Before Git with CVS.md b/sources/tech/20180707 Version Control Before Git with CVS.md deleted file mode 100644 index 4c59a2cfc0..0000000000 --- a/sources/tech/20180707 Version Control Before Git with CVS.md +++ /dev/null @@ -1,313 +0,0 @@ -（translating by runningwater) -Version Control Before Git with CVS -====== -Github was launched in 2008. If your software engineering career, like mine, is no older than Github, then Git may be the only version control software you have ever used. While people sometimes grouse about its steep learning curve or unintuitive interface, Git has become everyone’s go-to for version control. In Stack Overflow’s 2015 developer survey, 69.3% of respondents used Git, almost twice as many as used the second-most-popular version control system, Subversion. After 2015, Stack Overflow stopped asking developers about the version control systems they use, perhaps because Git had become so popular that the question was uninteresting. - -Git itself is not much older than Github. Linus Torvalds released the first version of Git in 2005. Though today younger developers might have a hard time conceiving of a world where the term “version control software” didn’t more or less just mean Git, such a world existed not so long ago. There were lots of alternatives to choose from. Open source developers preferred Subversion, enterprises and video game companies used Perforce (some still do), while the Linux kernel project famously relied on a version control system called BitKeeper. - -Some of these systems, particularly BitKeeper, might feel familiar to a young Git user transported back in time. Most would not. BitKeeper aside, the version control systems that came before Git worked according to a fundamentally different paradigm. In a taxonomy offered by Eric Sink, author of Version Control by Example, Git is a third-generation version control system, while most of Git’s predecessors, the systems popular in the 1990s and early 2000s, are second-generation version control systems. Where third-generation version control systems are distributed, second-generation version control systems are centralized. You have almost certainly heard Git described as a “distributed” version control system before. I never quite understood the distributed/centralized distinction, at least not until I installed and experimented with a centralized second-generation version control system myself. - -The system I installed was CVS. CVS, short for Concurrent Versions System, was the very first second-generation version control system. It was also the most popular version control system for about a decade until it was replaced in 2000 by Subversion. Even then, Subversion was supposed to be “CVS but better,” which only underscores how dominant CVS had become throughout the 1990s. - -CVS was first developed in 1986 by a Dutch computer scientist named Dick Grune, who was looking for a way to collaborate with his students on a compiler project. CVS was initially little more than a collection of shell scripts wrapping RCS (Revision Control System), a first-generation version control system that Grune wanted to improve. RCS works according to a pessimistic locking model, meaning that no two programmers can work on a single file at once. In order to edit a file, you have to first ask RCS for an exclusive lock on the file, which you keep until you are finished editing. If someone else is already editing a file you need to edit, you have to wait. CVS improved on RCS and ushered in the second generation of version control systems by trading the pessimistic locking model for an optimistic one. Programmers could now edit the same file at the same time, merging their edits and resolving any conflicts later. (Brian Berliner, an engineer who later took over the CVS project, wrote a very readable [paper][1] about CVS’ innovations in 1990.) - -In that sense, CVS wasn’t all that different from Git, which also works according to an optimistic model. But that’s where the similarities end. In fact, when Linus Torvalds was developing Git, one of his guiding principles was WWCVSND, or “What Would CVS Not Do.” Whenever he was in doubt about a decision, he strove to choose the option that had not been chosen in the design of CVS. So even though CVS predates Git by over a decade, it influenced Git as a kind of negative template. - -I’ve really enjoyed playing around with CVS. I think there’s no better way to understand why Git’s distributed nature is such an improvement on what came before. So I invite you to come along with me on an exciting journey and spend the next ten minutes of your life learning about a piece of software nobody has used in the last decade. (See correction.) - -### Getting Started with CVS - -Instructions for installing CVS can be found on the [project’s homepage][2]. On MacOS, you can install CVS using Homebrew. - -Since CVS is centralized, it distinguishes between the client-side universe and the server-side universe in a way that something like Git does not. The distinction is not so pronounced that there are different executables. But in order to start using CVS, even on your own machine, you’ll have to set up the CVS backend. - -The CVS backend, the central store for all your code, is called the repository. Whereas in Git you would typically have a repository for every project, in CVS the repository holds all of your projects. There is one central repository for everything, though there are ways to work with only a project at a time. - -To create a local repository, you run the `init` command. You would do this somewhere global like your home directory. - -``` -$ cvs -d ~/sandbox init -``` - -CVS allows you to pass options to either the `cvs` command itself or to the `init` subcommand. Options that appear after the `cvs` command are global in nature, while options that appear after the subcommand are specific to the subcommand. In this case, the `-d` flag is global. Here it happens to tell CVS where we want to create our repository, but in general the `-d` flag points to the location of the repository we want to use for any given action. It can be tedious to supply the `-d` flag all the time, so the `CVSROOT` environment variable can be set instead. - -Since we’re working locally, we’ve just passed a path for our `-d` argument, but we could also have included a hostname. - -The command creates a directory called `sandbox` in your home directory. If you list the contents of `sandbox`, you’ll find that it contains another directory called `CVSROOT`. This directory, not to be confused with the environment variable, holds administrative files for the repository. - -Congratulations! You’ve just created your first CVS repository. - -### Checking In Code - -Let’s say that you’ve decided to keep a list of your favorite colors. You are an artistically inclined but extremely forgetful person. You type up your list of colors and save it as a file called `favorites.txt`: - -``` -blue -orange -green - -definitely not yellow -``` - -Let’s also assume that you’ve saved your file in a new directory called `colors`. Now you’d like to put your favorite color list under version control, because fifty years from now it will be interesting to look back and see how your tastes changed through time. - -In order to do that, you will have to import your directory as a new CVS project. You can do that using the `import` command: - -``` -$ cvs -d ~/sandbox import -m "" colors colors initial -N colors/favorites.txt - -No conflicts created by this import -``` - -Here we are specifying the location of our repository with the `-d` flag again. The remaining arguments are passed to the `import` subcommand. We have to provide a message, but here we don’t really need one, so we’ve left it blank. The next argument, `colors`, specifies the name of our new directory in the repository; here we’ve just used the same name as the directory we are in. The last two arguments specify the vendor tag and the release tag respectively. We’ll talk more about tags in a minute. - -You’ve just pulled your “colors” project into the CVS repository. There are a couple different ways to go about bringing code into CVS, but this is the method recommended by [Pragmatic Version Control Using CVS][3], the Pragmatic Programmer book about CVS. What makes this method a little awkward is that you then have to check out your work fresh, even though you’ve already got an existing `colors` directory. Instead of using that directory, you’re going to delete it and then check out the version that CVS already knows about: - -``` -$ cvs -d ~/sandbox co colors -cvs checkout: Updating colors -U colors/favorites.txt -``` - -This will create a new directory, also called `colors`. In this directory you will find your original `favorites.txt` file along with a directory called `CVS`. The `CVS` directory is basically CVS’ equivalent of the `.git` directory in every Git repository. - -### Making Changes - -Get ready for a trip. - -Just like Git, CVS has a `status` subcommand: - -``` -$ cvs status -cvs status: Examining . -=================================================================== -File: favorites.txt Status: Up-to-date - - Working revision: 1.1.1.1 2018-07-06 19:27:54 -0400 - Repository revision: 1.1.1.1 /Users/sinclairtarget/sandbox/colors/favorites.txt,v - Commit Identifier: fD7GYxt035GNg8JA - Sticky Tag: (none) - Sticky Date: (none) - Sticky Options: (none) -``` - -This is where things start to look alien. CVS doesn’t have commit objects. In the above, there is something called a “Commit Identifier,” but this might be only a relatively recent edition—no mention of a “Commit Identifier” appears in Pragmatic Version Control Using CVS, which was published in 2003. (The last update to CVS was released in 2008.) - -Whereas with Git you’d talk about the version of a file associated with commit `45de392`, in CVS files are versioned separately. The first version of your file is version 1.1, the next version is 1.2, and so on. When branches are involved, extra numbers are appended, so you might end up with something like the `1.1.1.1` above, which appears to be the default in our case even though we haven’t created any branches. - -If you were to run `cvs log` (equivalent to `git log`) in a project with lots of files and commits, you’d see an individual history for each file. You might have a file at version 1.2 and a file at version 1.14 in the same project. - -Let’s go ahead and make a change to version 1.1 of our `favorites.txt` file: - -``` - blue - orange - green -+cyan - - definitely not yellow -``` - -Once we’ve made the change, we can run `cvs diff` to see what CVS thinks we’ve done: - -``` -$ cvs diff -cvs diff: Diffing . -Index: favorites.txt -=================================================================== -RCS file: /Users/sinclairtarget/sandbox/colors/favorites.txt,v -retrieving revision 1.1.1.1 -diff -r1.1.1.1 favorites.txt -3a4 -> cyan -``` - -CVS recognizes that we added a new line containing the color “cyan” to the file. (Actually, it says we’ve made changes to the “RCS” file; you can see that CVS never fully escaped its original association with RCS.) The diff we are being shown is the diff between the copy of `favorites.txt` in our working directory and the 1.1.1.1 version stored in the repository. - -In order to update the version stored in the repository, we have to commit the change. In Git, this would be a multi-step process. We’d have to stage the change so that it appears in our index. Then we’d commit the change. Finally, to make the change visible to anyone else, we’d have to push the commit up to the origin repository. - -In CVS, all of these things happen when you run `cvs commit`. CVS just bundles up all the changes it can find and puts them in the repository: - -``` -$ cvs commit -m "Add cyan to favorites." -cvs commit: Examining . -/Users/sinclairtarget/sandbox/colors/favorites.txt,v <-- favorites.txt -new revision: 1.2; previous revision: 1.1 -``` - -I’m so used to Git that this strikes me as terrifying. Without an opportunity to stage changes, any old thing that you’ve touched in your working directory might end up as part of the public repository. Did you passive-aggressively rewrite a coworker’s poorly implemented function out of cathartic necessity, never intending for him to know? Too bad, he now thinks you’re a dick. You also can’t edit your commits before pushing them, since a commit is a push. Do you enjoy spending 40 minutes repeatedly running `git rebase -i` until your local commit history flows like the derivation of a mathematical proof? Sorry, you can’t do that here, and everyone is going to find out that you don’t actually write your tests first. - -But I also now understand why so many people find Git needlessly complicated. If `cvs commit` is what you were used to, then I’m sure staging and pushing changes would strike you as a pointless chore. - -When people talk about Git being a “distributed” system, this is primarily the difference they mean. In CVS, you can’t make commits locally. A commit is a submission of code to the central repository, so it’s not something you can do without a connection. All you’ve got locally is your working directory. In Git, you have a full-fledged local repository, so you can make commits all day long even while disconnected. And you can edit those commits, revert, branch, and cherry pick as much as you want, without anybody else having to know. - -Since commits were a bigger deal, CVS users often made them infrequently. Commits would contain as many changes as today we might expect to see in a ten-commit pull request. This was especially true if commits triggered a CI build and an automated test suite. - -If we now run `cvs status`, we can see that we have a new version of our file: - -``` -$ cvs status -cvs status: Examining . -=================================================================== -File: favorites.txt Status: Up-to-date - - Working revision: 1.2 2018-07-06 21:18:59 -0400 - Repository revision: 1.2 /Users/sinclairtarget/sandbox/colors/favorites.txt,v - Commit Identifier: pQx5ooyNk90wW8JA - Sticky Tag: (none) - Sticky Date: (none) - Sticky Options: (none) -``` - -### Merging - -As mentioned above, in CVS you can edit a file that someone else is already editing. That was CVS’ big improvement on RCS. What happens when you need to bring your changes back together? - -Let’s say that you have invited some friends to add their favorite colors to your list. While they are adding their colors, you decide that you no longer like the color green and remove it from the list. - -When you go to commit your changes, you might discover that CVS notices a problem: - -``` -$ cvs commit -m "Remove green" -cvs commit: Examining . -cvs commit: Up-to-date check failed for `favorites.txt' -cvs [commit aborted]: correct above errors first! -``` - -It looks like your friends committed their changes first. So your version of `favorites.txt` is not up-to-date with the version in the repository. If you run `cvs status`, you’ll see that your local copy of `favorites.txt` is version 1.2 with some local changes, but the repository version is 1.3: - -``` -$ cvs status -cvs status: Examining . -=================================================================== -File: favorites.txt Status: Needs Merge - - Working revision: 1.2 2018-07-07 10:42:43 -0400 - Repository revision: 1.3 /Users/sinclairtarget/sandbox/colors/favorites.txt,v - Commit Identifier: 2oZ6n0G13bDaldJA - Sticky Tag: (none) - Sticky Date: (none) - Sticky Options: (none) -``` - -You can run `cvs diff` to see exactly what the differences between 1.2 and 1.3 are: - -``` -$ cvs diff -r HEAD favorites.txt -Index: favorites.txt -=================================================================== -RCS file: /Users/sinclairtarget/sandbox/colors/favorites.txt,v -retrieving revision 1.3 -diff -r1.3 favorites.txt -3d2 -< green -7,10d5 -< -< pink -< hot pink -< bubblegum pink -``` - -It seems that our friends really like pink. In any case, they’ve edited a different part of the file than we have, so the changes are easy to merge. CVS can do that for us when we run `cvs update`, which is similar to `git pull`: - -``` -$ cvs update -cvs update: Updating . -RCS file: /Users/sinclairtarget/sandbox/colors/favorites.txt,v -retrieving revision 1.2 -retrieving revision 1.3 -Merging differences between 1.2 and 1.3 into favorites.txt -M favorites.txt -``` - -If you now take a look at `favorites.txt`, you’ll find that it has been modified to include the changes that your friends made to the file. Your changes are still there too. Now you are free to commit the file: - -``` -$ cvs commit -cvs commit: Examining . -/Users/sinclairtarget/sandbox/colors/favorites.txt,v <-- favorites.txt -new revision: 1.4; previous revision: 1.3 -``` - -The end result is what you’d get in Git by running `git pull --rebase`. Your changes have been added on top of your friends’ changes. There is no “merge commit.” - -Sometimes, changes to the same file might be incompatible. If your friends had changed “green” to “olive,” for example, that would have conflicted with your change removing “green” altogether. In the early days of CVS, this was exactly the kind of case that caused people to worry that CVS wasn’t safe; RCS’ pessimistic locking ensured that such a case could never arise. But CVS guarantees safety by making sure that nobody’s changes get overwritten automatically. You have to tell CVS which change you want to keep going forward, so when you run `cvs update`, CVS marks up the file with both changes in the same way that Git does when Git detects a merge conflict. You then have to manually edit the file and pick the change you want to keep. - -The interesting thing to note here is that merge conflicts have to be fixed before you can commit. This is another consequence of CVS’ centralized nature. In Git, you don’t have to worry about resolving merges until you push the commits you’ve got locally. - -Since CVS doesn’t have easily addressable commit objects, the only way to group a collection of changes is to mark a particular working directory state with a tag. - -Creating a tag is easy: - -``` -$ cvs tag VERSION_1_0 -cvs tag: Tagging . -T favorites.txt -``` - -You’ll later be able to return files to this state by running `cvs update` and passing the tag to the `-r` flag: - -``` -$ cvs update -r VERSION_1_0 -cvs update: Updating . -U favorites.txt -``` - -Because you need a tag to rewind to an earlier working directory state, CVS encourages a lot of preemptive tagging. Before major refactors, for example, you might create a `BEFORE_REFACTOR_01` tag that you could later use if the refactor went wrong. People also used tags if they wanted to generate project-wide diffs. Basically, all the things we routinely do today with commit hashes have to be anticipated and planned for with CVS, since you needed to have the tags available already. - -Branches can be created in CVS, sort of. Branches are just a special kind of tag: - -``` -$ cvs rtag -b TRY_EXPERIMENTAL_THING colors -cvs rtag: Tagging colors -``` - -That only creates the branch (in full view of everyone, by the way), so you still need to switch to it using `cvs update`: - -``` -$ cvs update -r TRY_EXPERIMENTAL_THING -``` - -The above commands switch onto the new branch in your current working directory, but Pragmatic Version Control Using CVS actually advises that you create a new directory to hold your new branch. Presumably its authors found switching directories easier than switching branches in CVS. - -Pragmatic Version Control Using CVS also advises against creating branches off of an existing branch. They recommend only creating branches off of the mainline branch, which in Git is known as `master`. In general, branching was considered an “advanced” CVS skill. In Git, you might start a new branch for almost any trivial reason, but in CVS branching was typically used only when really necessary, such as for releases. - -A branch could later be merged back into the mainline using `cvs update` and the `-j` flag: - -``` -$ cvs update -j TRY_EXPERIMENTAL_THING -``` - -### Thanks for the Commit Histories - -In 2007, Linus Torvalds gave [a talk][4] about Git at Google. Git was very new then, so the talk was basically an attempt to persuade a roomful of skeptical programmers that they should use Git, even though Git was so different from anything then available. If you haven’t already seen the talk, I highly encourage you to watch it. Linus is an entertaining speaker, even if he never fails to be his brash self. He does an excellent job of explaining why the distributed model of version control is better than the centralized one. A lot of his criticism is reserved for CVS in particular. - -Git is a [complex tool][5]. Learning it can be a frustrating experience. But I’m also continually amazed at the things that Git can do. In comparison, CVS is simple and straightforward, though often unable to do many of the operations we now take for granted. Going back and using CVS for a while is an excellent way to find yourself with a new appreciation for Git’s power and flexibility. It illustrates well why understanding the history of software development can be so beneficial—picking up and re-examining obsolete tools will teach you volumes about the why behind the tools we use today. - -If you enjoyed this post, more like it come out every two weeks! Follow [@TwoBitHistory][6] on Twitter or subscribe to the [RSS feed][7] to make sure you know when a new post is out. - -#### Correction - -I’ve been told that there are many organizations, particularly risk-adverse organizations that do things like make medical device software, that still use CVS. Programmers in these organizations have developed little tricks for working around CVS’ limitations, such as making a new branch for almost every change to avoid committing directly to `HEAD`. (Thanks to Michael Kohne for pointing this out.) - --------------------------------------------------------------------------------- - -via: https://twobithistory.org/2018/07/07/cvs.html - -作者：[Two-Bit History][a] -选题：[lujun9972][b] -译者：[runningwater](https://github.com/runningwater) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://twobithistory.org -[b]: https://github.com/lujun9972 -[1]: https://docs.freebsd.org/44doc/psd/28.cvs/paper.pdf -[2]: https://www.nongnu.org/cvs/ -[3]: http://shop.oreilly.com/product/9780974514000.do -[4]: https://www.youtube.com/watch?v=4XpnKHJAok8 -[5]: https://xkcd.com/1597/ -[6]: https://twitter.com/TwoBitHistory -[7]: https://twobithistory.org/feed.xml diff --git a/sources/tech/20180709 5 Firefox extensions to protect your privacy.md b/sources/tech/20180709 5 Firefox extensions to protect your privacy.md deleted file mode 100644 index 848856fe07..0000000000 --- a/sources/tech/20180709 5 Firefox extensions to protect your privacy.md +++ /dev/null @@ -1,54 +0,0 @@ -5 Firefox extensions to protect your privacy -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/biz_cinderblock_cloud_yellowhat.jpg?itok=sJdlsYTF) - -In the wake of the Cambridge Analytica story, I took a hard look at how far I had let Facebook penetrate my online presence. As I'm generally concerned about single points of failure (or compromise), I am not one to use social logins. I use a password manager and create unique logins for every site (and you should, too). - -What I was most perturbed about was the pervasive intrusion Facebook was having on my digital life. I uninstalled the Facebook mobile app almost immediately after diving into the Cambridge Analytica story. I also [disconnected all apps, games, and websites][1] from Facebook. Yes, this will change your experience on Facebook, but it will also protect your privacy. As a veteran with friends spread out across the globe, maintaining the social connectivity of Facebook is important to me. - -I went about the task of scrutinizing other services as well. I checked Google, Twitter, GitHub, and more for any unused connected applications. But I know that's not enough. I need my browser to be proactive in preventing behavior that violates my privacy. I began the task of figuring out how best to do that. Sure, I can lock down a browser, but I need to make the sites and tools I use work while trying to keep them from leaking data. - -Following are five tools that will protect your privacy while using your browser. The first three extensions are available for Firefox and Chrome, while the latter two are only available for Firefox. - -### Privacy Badger - -[Privacy Badger][2] has been my go-to extension for quite some time. Do other content or ad blockers do a better job? Maybe. The problem with a lot of content blockers is that they are "pay for play." Meaning they have "partners" that get whitelisted for a fee. That is the antithesis of why content blockers exist. Privacy Badger is made by the Electronic Frontier Foundation (EFF), a nonprofit entity with a donation-based business model. Privacy Badger promises to learn from your browsing habits and requires minimal tuning. For example, I have only had to whitelist a handful of sites. Privacy Badger also allows granular controls of exactly which trackers are enabled on what sites. It's my #1, must-install extension, no matter the browser. - -### DuckDuckGo Privacy Essentials - -The search engine DuckDuckGo has typically been privacy-conscious. [DuckDuckGo Privacy Essentials][3] works across major mobile devices and browsers. It's unique in the sense that it grades sites based on the settings you give them. For example, Facebook gets a D, even with Privacy Protection enabled. Meanwhile, [chrisshort.net][4] gets a B with Privacy Protection enabled and a C with it disabled. If you're not keen on EFF or Privacy Badger for whatever reason, I would recommend DuckDuckGo Privacy Essentials (choose one, not both, as they essentially do the same thing). - -### HTTPS Everywhere - -[HTTPS Everywhere][5] is another extension from the EFF. According to HTTPS Everywhere, "Many sites on the web offer some limited support for encryption over HTTPS, but make it difficult to use. For instance, they may default to unencrypted HTTP or fill encrypted pages with links that go back to the unencrypted site. The HTTPS Everywhere extension fixes these problems by using clever technology to rewrite requests to these sites to HTTPS." While a lot of sites and browsers are getting better about implementing HTTPS, there are a lot of sites that still need help. HTTPS Everywhere will try its best to make sure your traffic is encrypted. - -### NoScript Security Suite - -[NoScript Security Suite][6] is not for the faint of heart. While the Firefox-only extension "allows JavaScript, Java, Flash, and other plugins to be executed only by trusted websites of your choice," it doesn't do a great job at figuring out what your choices are. But, make no mistake, a surefire way to prevent leaking data is not executing code that could leak it. NoScript enables that via its "whitelist-based preemptive script blocking." This means you will need to build the whitelist as you go for sites not already on it. Note that NoScript is only available for Firefox. - -### Facebook Container - -[Facebook Container][7] makes Firefox the only browser where I will use Facebook. "Facebook Container works by isolating your Facebook identity into a separate container that makes it harder for Facebook to track your visits to other websites with third-party cookies." This means Facebook cannot snoop on activity happening elsewhere in your browser. Suddenly those creepy ads will stop appearing so frequently (assuming you uninstalled the Facebook app from your mobile devices). Using Facebook in an isolated space will prevent any additional collection of data. Remember, you've given Facebook data already, and Facebook Container can't prevent that data from being shared. - -These are my go-to extensions for browser privacy. What are yours? Please share them in the comments. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/7/firefox-extensions-protect-privacy - -作者：[Chris Short][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/chrisshort -[1]:https://www.facebook.com/help/211829542181913 -[2]:https://www.eff.org/privacybadger -[3]:https://duckduckgo.com/app -[4]:https://chrisshort.net -[5]:https://www.eff.org/https-everywhere -[6]:https://noscript.net/ -[7]:https://addons.mozilla.org/en-US/firefox/addon/facebook-container/ diff --git a/sources/tech/20180710 Users, Groups, and Other Linux Beasts.md b/sources/tech/20180710 Users, Groups, and Other Linux Beasts.md deleted file mode 100644 index 6083111a32..0000000000 --- a/sources/tech/20180710 Users, Groups, and Other Linux Beasts.md +++ /dev/null @@ -1,153 +0,0 @@ -Users, Groups, and Other Linux Beasts -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/flamingo-2458782_1920.jpg?itok=_gkzGGx5) - -Having reached this stage, [after seeing how to manipulate folders/directories][1], but before flinging ourselves headlong into fiddling with files, we have to brush up on the matter of _permissions_ , _users_ and _groups_. Luckily, [there is already an excellent and comprehensive tutorial on this site that covers permissions][2], so you should go and read that right now. In a nutshell: you use permissions to establish who can do stuff to files and directories and what they can do with each file and directory -- read from it, write to it, move it, erase it, etc. - -To try everything this tutorial covers, you'll need to create a new user on your system. Let's be practical and make a user for anybody who needs to borrow your computer, that is, what we call a _guest account_. - -**WARNING:** _Creating and especially deleting users, along with home directories, can seriously damage your system if, for example, you remove your own user and files by mistake. You may want to practice on another machine which is not your main work machine or on a virtual machine. Regardless of whether you want to play it safe, or not, it is always a good idea to back up your stuff frequently, check the backups have worked correctly, and save yourself a lot of gnashing of teeth later on._ - -### A New User - -You can create a new user with the `useradd` command. Run `useradd` with superuser/root privileges, that is using `sudo` or `su`, depending on your system, you can do: -``` -sudo useradd -m guest - -``` - -... and input your password. Or do: -``` -su -c "useradd -m guest" - -``` - -... and input the password of root/the superuser. - -( _For the sake of brevity, we'll assume from now on that you get superuser/root privileges by using`sudo`_ ). - -By including the `-m` argument, `useradd` will create a home directory for the new user. You can see its contents by listing _/home/guest_. - -Next you can set up a password for the new user with -``` -sudo passwd guest - -``` - -Or you could also use `adduser`, which is interactive and asks you a bunch of questions, including what shell you want to assign the user (yes, there are more than one), where you want their home directory to be, what groups you want them to belong to (more about that in a second) and so on. At the end of running `adduser`, you get to set the password. Note that `adduser` is not installed by default on many distributions, while `useradd` is. - -Incidentally, you can get rid of a user with `userdel`: -``` -sudo userdel -r guest - -``` - -With the `-r` option, `userdel` not only removes the _guest_ user, but also deletes their home directory and removes their entry in the mailing spool, if they had one. - -### Skeletons at Home - -Talking of users' home directories, depending on what distro you're on, you may have noticed that when you use the `-m` option, `useradd` populates a user's directory with subdirectories for music, documents, and whatnot as well as an assortment of hidden files. To see everything in you guest's home directory run `sudo ls -la /home/guest`. - -What goes into a new user's directory is determined by a skeleton directory which is usually _/etc/skel_. Sometimes it may be a different directory, though. To check which directory is being used, run: -``` -useradd -D -GROUP=100 -HOME=/home -INACTIVE=-1 -EXPIRE= -SHELL=/bin/bash -SKEL=/etc/skel -CREATE_MAIL_SPOOL=no - -``` - -This gives you some extra interesting information, but what you're interested in right now is the `SKEL=/etc/skel` line. In this case, and as is customary, it is pointing to _/etc/skel/_. - -As everything is customizable in Linux, you can, of course, change what gets put into a newly created user directory. Try this: Create a new directory in _/etc/skel/_ : -``` -sudo mkdir /etc/skel/Documents - -``` - -And create a file containing a welcome text and copy it over: -``` -sudo cp welcome.txt /etc/skel/Documents - -``` - -Now delete the guest account: -``` -sudo userdel -r guest - -``` - -And create it again: -``` -sudo useradd -m guest - -``` - -Hey presto! Your _Documents/_ directory and _welcome.txt_ file magically appear in the guest's home directory. - -You can also modify other things when you create a user by editing _/etc/default/useradd_. Mine looks like this: -``` -GROUP=users -HOME=/home -INACTIVE=-1 -EXPIRE= -SHELL=/bin/bash -SKEL=/etc/skel -CREATE_MAIL_SPOOL=no - -``` - -Most of these options are self-explanatory, but let's take a closer look at the `GROUP` option. - -### Herd Mentality - -Instead of assigning permissions and privileges to users one by one, Linux and other Unix-like operating systems rely on _groups_. A group is a what you imagine it to be: a bunch of users that are related in some way. On your system you may have a group of users that are allowed to use the printer. They would belong to the _lp_ (for " _line printer_ ") group. The members of the _wheel_ group were traditionally the only ones who could become superuser/root by using _su_. The _network_ group of users can bring up and power down the network. And so on and so forth. - -Different distributions have different groups and groups with the same or similar names have different privileges also depending on the distribution you are using. So don't be surprised if what you read in the prior paragraph doesn't match what is going on in your system. - -Either way, to see which groups are on your system you can use: -``` -getent group - -``` - -The `getent` command lists the contents of some of the system's databases. - -To find out which groups your current user belongs to, try: -``` -groups - -``` - -When you create a new user with `useradd`, unless you specify otherwise, the user will only belong to one group: their own. A _guest_ user will belong to a _guest_ group and the group gives the user the power to administer their own stuff and that is about it. - -You can create new groups and then add users to them at will with the `groupadd` command: -``` -sudo groupadd photos - -``` - -will create the _photos_ group, for example. Next time, we’ll use this to build a shared directory all members of the group can read from and write to, and we'll learn even more about permissions and privileges. Stay tuned! - -Learn more about Linux through the free ["Introduction to Linux" ][3]course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/learn/intro-to-linux/2018/7/users-groups-and-other-linux-beasts - -作者：[Paul Brown][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/bro66 -[1]:https://www.linux.com/blog/learn/2018/5/manipulating-directories-linux -[2]:https://www.linux.com/learn/understanding-linux-file-permissions -[3]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20180716 Users, Groups and Other Linux Beasts- Part 2.md b/sources/tech/20180716 Users, Groups and Other Linux Beasts- Part 2.md deleted file mode 100644 index b164bb6cf5..0000000000 --- a/sources/tech/20180716 Users, Groups and Other Linux Beasts- Part 2.md +++ /dev/null @@ -1,110 +0,0 @@ -Users, Groups and Other Linux Beasts: Part 2 -====== -![](https://www.linux.com/blog/learn/intro-to-linux/2018/7/users-groups-and-other-linux-beasts-part-2) -In this ongoing tour of Linux, we’ve looked at [how to manipulate folders/directories][1], and now we’re continuing our discussion of _permissions_ , _users_ and _groups_ , which are necessary to establish who can manipulate which files and directories. [Last time,][2] we showed how to create new users, and now we’re going to dive right back in: - -You can create new groups and then add users to them at will with the `groupadd` command. For example, using: -``` -sudo groupadd photos - -``` - -will create the _photos_ group. - -You’ll need to [create a directory][1] hanging off the root directory: -``` -sudo mkdir /photos - -``` - -If you run `ls -l /`, one of the lines will be: -``` -drwxr-xr-x 1 root root 0 jun 26 21:14 photos - -``` - -The first _root_ in the output is the user owner and the second _root_ is the group owner. - -To transfer the ownership of the _/photos_ directory to the _photos_ group, use -``` -chgrp photos /photos - -``` - -The `chgrp` command typically takes two parameters, the first parameter is the group that will take ownership of the file or directory and the second is the file or directory you want to give over to the the group. - -Next, run `ls -l /` and you'll see the line has changed to: -``` -drwxr-xr-x 1 root photos 0 jun 26 21:14 photos - -``` - -You have successfully transferred the ownership of your new directory over to the _photos_ group. - -Then, add your own user and the _guest_ user to the _photos_ group: -``` -sudo usermod -a -G photos -sudo usermod guest -a -G photos - -``` - -You may have to log out and log back in to see the changes, but, when you do, running `groups` will show _photos_ as one of the groups you belong to. - -A couple of things to point out about the `usermod` command shown above. First: Be careful not to use the `-g` option instead of `-G`. The `-g` option changes your primary group and could lock you out of your stuff if you use it by accident. `-G`, on the other hand, _adds_ you to the groups listed and doesn't mess with the primary group. If you want to add your user to more groups than one, list them one after another, separated by commas, no spaces, after `-G`: -``` -sudo usermod -a -G photos,pizza,spaceforce - -``` - -Second: Be careful not to forget the `-a` parameter. The `-a` parameter stands for _append_ and attaches the list of groups you pass to `-G` to the ones you already belong to. This means that, if you don't include `-a`, the list of groups you already belong to, will be overwritten, again locking you out from stuff you need. - -Neither of these are catastrophic problems, but it will mean you will have to add your user back manually to all the groups you belonged to, which can be a pain, especially if you have lost access to the _sudo_ and _wheel_ group. - -### Permits, Please! - -There is still one more thing to do before you can copy images to the _/photos_ directory. Notice how, when you did `ls -l /` above, permissions for that folder came back as _drwxr-xr-x_. - -If you read [the article I recommended at the beginning of this post][3], you'll know that the first _d_ indicates that the entry in the file system is a directory, and then you have three sets of three characters ( _rwx_ , _r-x_ , _r-x_ ) that indicate the permissions for the user owner ( _rwx_ ) of the directory, then the group owner ( _r-x_ ), and finally the rest of the users ( _r-x_ ). This means that the only person who has write permissions so far, that is, the only person who can copy or create files in the _/photos_ directory, is the _root_ user. - -But [that article I mentioned also tells you how to change the permissions for a directory or file][3]: -``` -sudo chmod g+w /photos - -``` - -Running `ls -l /` after that will give you _/photos_ permissions as _drwxrwxr-x_ which is what you want: group members can now write into the directory. - -Now you can try and copy an image or, indeed, any other file to the directory and it should go through without a problem: -``` -cp image.jpg /photos - -``` - -The _guest_ user will also be able to read and write from the directory. They will also be able to read and write to it, and even move or delete files created by other users within the shared directory. - -### Conclusion - -The permissions and privileges system in Linux has been honed over decades. inherited as it is from the old Unix systems of yore. As such, it works very well and is well thought out. Becoming familiar with it is essential for any Linux sysadmin. In fact, you can't do much admining at all unless you understand it. But, it's not that hard. - -Next time, we'll be dive into files and see the different ways of creating, manipulating, and destroying them in creative ways. Always fun, that last one. - -See you then! - -Learn more about Linux through the free ["Introduction to Linux" ][4]course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/learn/intro-to-linux/2018/7/users-groups-and-other-linux-beasts-part-2 - -作者：[Paul Brown][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://www.linux.com/users/bro66 -[1]:https://www.linux.com/blog/learn/2018/5/manipulating-directories-linux -[2]:https://www.linux.com/learn/intro-to-linux/2018/7/users-groups-and-other-linux-beasts -[3]:https://www.linux.com/learn/understanding-linux-file-permissions -[4]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20180725 Build an interactive CLI with Node.js.md b/sources/tech/20180725 Build an interactive CLI with Node.js.md index f240e51efd..6ec13f1cfc 100644 --- a/sources/tech/20180725 Build an interactive CLI with Node.js.md +++ b/sources/tech/20180725 Build an interactive CLI with Node.js.md @@ -1,5 +1,3 @@ -translating by Flowsnow - Build an interactive CLI with Node.js ====== diff --git a/sources/tech/20180727 How to analyze your system with perf and Python.md b/sources/tech/20180727 How to analyze your system with perf and Python.md index 4573ed1ee0..c1be98cc0e 100644 --- a/sources/tech/20180727 How to analyze your system with perf and Python.md +++ b/sources/tech/20180727 How to analyze your system with perf and Python.md @@ -1,7 +1,3 @@ -**translating by [erlinux](https://github.com/erlinux)** -**PROJECT MANAGEMENT TOOL called [gn2.sh](https://github.com/lctt/lctt-cli)** - - How to analyze your system with perf and Python ====== diff --git a/sources/tech/20180803 How to use Fedora Server to create a router - gateway.md b/sources/tech/20180803 How to use Fedora Server to create a router - gateway.md index 0394826c10..934693d1cf 100644 --- a/sources/tech/20180803 How to use Fedora Server to create a router - gateway.md +++ b/sources/tech/20180803 How to use Fedora Server to create a router - gateway.md @@ -1,3 +1,5 @@ +ScarboroughCoral translating! + How to use Fedora Server to create a router / gateway ====== diff --git a/sources/tech/20180806 GPaste Is A Great Clipboard Manager For Gnome Shell.md b/sources/tech/20180806 GPaste Is A Great Clipboard Manager For Gnome Shell.md deleted file mode 100644 index be86776740..0000000000 --- a/sources/tech/20180806 GPaste Is A Great Clipboard Manager For Gnome Shell.md +++ /dev/null @@ -1,98 +0,0 @@ -translating---geekpi - -GPaste Is A Great Clipboard Manager For Gnome Shell -====== -**[GPaste][1] is a clipboard management system that consists of a library, daemon, and interfaces for the command line and Gnome (using a native Gnome Shell extension).** - -A clipboard manager allows keeping track of what you're copying and pasting, providing access to previously copied items. GPaste, with its native Gnome Shell extension, makes the perfect addition for those looking for a Gnome clipboard manager. - -[![GPaste Gnome Shell extension Ubuntu 18.04][2]][3] -GPaste Gnome Shell extension -**Using GPaste in Gnome, you get a configurable, searchable clipboard history, available with a click on the top panel. GPaste remembers not only the text you copy, but also file paths and images** (the latter needs to be enabled from its settings as it's disabled by default). - -What's more, GPaste can detect growing lines, meaning it can detect when a new text copy is an extension of another and replaces it if it's true, useful for keeping your clipboard clean. - -From the extension menu you can pause GPaste from tracking the clipboard, and remove items from the clipboard history or the whole history. You'll also find a button that launches the GPaste user interface window. - -**If you prefer to use the keyboard, you can use a key shortcut to open the GPaste history from the top bar** (`Ctrl + Alt + H`), **or open the full GPaste GUI** (`Ctrl + Alt + G`). - -The tool also incorporates keyboard shortcuts to (can be changed): - - * delete the active item from history: `Ctrl + Alt + V` - - * **mark the active item as being a password (which obfuscates the clipboard entry in GPaste):** `Ctrl + Alt + S` - - * sync the clipboard to the primary selection: `Ctrl + Alt + O` - - * sync the primary selection to the clipboard: `Ctrl + Alt + P` - - * upload the active item to a pastebin service: `Ctrl + Alt + U` - -[![][4]][5] -GPaste GUI - -The GPaste interface window provides access to the clipboard history (with options to clear, edit or upload items), which can be searched, an option to pause GPaste from tracking the clipboard, restart the GPaste daemon, backup current clipboard history, as well as to its settings. - -[![][6]][7] -GPaste GUI - -From the GPaste UI you can change settings like: - - * Enable or disable the Gnome Shell extension - * Sync the daemon state with the extension's one - * Primary selection affects history - * Synchronize clipboard with primary selection - * Image support - * Trim items - * Detect growing lines - * Save history - * History settings like max history size, memory usage, max text item length, and more - * Keyboard shortcuts - - - -### Download GPaste - -[Download GPaste](https://github.com/Keruspe/GPaste) - -The Gpaste project page does not link to any GPaste binaries, and only source installation instructions. Users running Linux distributions other than Debian or Ubuntu (for which you'll find GPaste installation instructions below) can search their distro repositories for GPaste. - -Do not confuse GPaste with the GPaste Integration extension posted on the Gnome Shell extension website. That is a Gnome Shell extension that uses GPaste daemon, which is no longer maintained. The native Gnome Shell extension built into GPaste is still maintained. - -#### Install GPaste in Ubuntu (18.04, 16.04) or Debian (Jessie and newer) - -**For Debian, GPaste is available for Jessie and newer, while for Ubuntu, GPaste is in the repositories for 16.04 and newer (so it's available in the Ubuntu 18.04 Bionic Beaver).** - -**You can install GPaste (the daemon and the Gnome Shell extension) in Debian or Ubuntu using this command:** -``` -sudo apt install gnome-shell-extensions-gpaste gpaste - -``` - -After the installation completes, restart Gnome Shell by pressing `Alt + F2` and typing `r` , then pressing the `Enter` key. The GPaste Gnome Shell extension should now be enabled and its icon should show up on the top Gnome Shell panel. If it's not, use Gnome Tweaks (Gnome Tweak Tool) to enable the extension. - -**The GPaste 3.28.0 package from[Debian][8] and [Ubuntu][9] has a bug that makes it crash if the image support option is enabled, so do not enable this feature for now.** This was marked as - - --------------------------------------------------------------------------------- - -via: https://www.linuxuprising.com/2018/08/gpaste-is-great-clipboard-manager-for.html - -作者：[Logix][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://plus.google.com/118280394805678839070 -[1]:https://github.com/Keruspe/GPaste -[2]:https://2.bp.blogspot.com/-2ndArDBcrwY/W2gyhMc1kEI/AAAAAAAABS0/ZAe_onuGCacMblF733QGBX3XqyZd--WuACLcBGAs/s400/gpaste-gnome-shell-extension-ubuntu1804.png (Gpaste Gnome Shell) -[3]:https://2.bp.blogspot.com/-2ndArDBcrwY/W2gyhMc1kEI/AAAAAAAABS0/ZAe_onuGCacMblF733QGBX3XqyZd--WuACLcBGAs/s1600/gpaste-gnome-shell-extension-ubuntu1804.png -[4]:https://2.bp.blogspot.com/-7FBRsZJvYek/W2gyvzmeRxI/AAAAAAAABS4/LhokMFSn8_kZndrNB-BTP4W3e9IUuz9BgCLcBGAs/s640/gpaste-gui_1.png -[5]:https://2.bp.blogspot.com/-7FBRsZJvYek/W2gyvzmeRxI/AAAAAAAABS4/LhokMFSn8_kZndrNB-BTP4W3e9IUuz9BgCLcBGAs/s1600/gpaste-gui_1.png -[6]:https://4.bp.blogspot.com/-047ShYc6RrQ/W2gyz5FCf_I/AAAAAAAABTA/-o6jaWzwNpsSjG0QRwRJ5Xurq_A6dQ0sQCLcBGAs/s640/gpaste-gui_2.png -[7]:https://4.bp.blogspot.com/-047ShYc6RrQ/W2gyz5FCf_I/AAAAAAAABTA/-o6jaWzwNpsSjG0QRwRJ5Xurq_A6dQ0sQCLcBGAs/s1600/gpaste-gui_2.png -[8]:https://packages.debian.org/buster/gpaste -[9]:https://launchpad.net/ubuntu/+source/gpaste -[10]:https://www.imagination-land.org/posts/2018-04-13-gpaste-3.28.2-released.html diff --git a/sources/tech/20180814 HTTP request routing and validation with gorilla-mux.md b/sources/tech/20180814 HTTP request routing and validation with gorilla-mux.md deleted file mode 100644 index 410f692ad9..0000000000 --- a/sources/tech/20180814 HTTP request routing and validation with gorilla-mux.md +++ /dev/null @@ -1,674 +0,0 @@ -HTTP request routing and validation with gorilla/mux -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/data_metrics_analytics_desktop_laptop.png?itok=9QXd7AUr) - -The Go networking library includes the `http.ServeMux` structure type, which supports HTTP request multiplexing (routing): A web server routes an HTTP request for a hosted resource, with a URI such as /sales4today, to a code handler; the handler performs the appropriate logic before sending an HTTP response, typically an HTML page. Here’s a sketch of the architecture: -``` -                 +------------+     +--------+     +---------+ -HTTP request---->| web server |---->| router |---->| handler | -                 +------------+     +--------+     +---------+ -``` - -In a call to the `ListenAndServe` method to start an HTTP server -``` -http.ListenAndServe(":8888", nil) // args: port & router -``` - -a second argument of `nil` means that the `DefaultServeMux` is used for request routing. - -The `gorilla/mux` package has a `mux.Router` type as an alternative to either the `DefaultServeMux` or a customized request multiplexer. In the `ListenAndServe` call, a `mux.Router` instance would replace `nil` as the second argument. What makes the `mux.Router` so appealing is best shown through a code example: - -### 1\. A sample crud web app - -The crud web application (see below) supports the four CRUD (Create Read Update Delete) operations, which match four HTTP request methods: POST, GET, PUT, and DELETE, respectively. In the crud app, the hosted resource is a list of cliche pairs, each a cliche and a conflicting cliche such as this pair: -``` -Out of sight, out of mind. Absence makes the heart grow fonder. - -``` - -New cliche pairs can be added, and existing ones can be edited or deleted. - -**The crud web app** -``` -package main - -import ( -   "gorilla/mux" -   "net/http" -   "fmt" -   "strconv" -) - -const GETALL string = "GETALL" -const GETONE string = "GETONE" -const POST string   = "POST" -const PUT string    = "PUT" -const DELETE string = "DELETE" - -type clichePair struct { -   Id      int -   Cliche  string -   Counter string -} - -// Message sent to goroutine that accesses the requested resource. -type crudRequest struct { -   verb     string -   cp       *clichePair -   id       int -   cliche   string -   counter  string -   confirm  chan string -} - -var clichesList = []*clichePair{} -var masterId = 1 -var crudRequests chan *crudRequest - -// GET / -// GET /cliches -func ClichesAll(res http.ResponseWriter, req *http.Request) { -   cr := &crudRequest{verb: GETALL, confirm: make(chan string)} -   completeRequest(cr, res, "read all") -} - -// GET /cliches/id -func ClichesOne(res http.ResponseWriter, req *http.Request) { -   id := getIdFromRequest(req) -   cr := &crudRequest{verb: GETONE, id: id, confirm: make(chan string)} -   completeRequest(cr, res, "read one") -} - -// POST /cliches - -func ClichesCreate(res http.ResponseWriter, req *http.Request) { - -   cliche, counter := getDataFromRequest(req) - -   cp := new(clichePair) - -   cp.Cliche = cliche - -   cp.Counter = counter - -   cr := &crudRequest{verb: POST, cp: cp, confirm: make(chan string)} - -   completeRequest(cr, res, "create") - -} - - - -// PUT /cliches/id - -func ClichesEdit(res http.ResponseWriter, req *http.Request) { - -   id := getIdFromRequest(req) - -   cliche, counter := getDataFromRequest(req) - -   cr := &crudRequest{verb: PUT, id: id, cliche: cliche, counter: counter, confirm: make(chan string)} - -   completeRequest(cr, res, "edit") - -} - - - -// DELETE /cliches/id - -func ClichesDelete(res http.ResponseWriter, req *http.Request) { - -   id := getIdFromRequest(req) - -   cr := &crudRequest{verb: DELETE, id: id, confirm: make(chan string)} - -   completeRequest(cr, res, "delete") - -} - - - -func completeRequest(cr *crudRequest, res http.ResponseWriter, logMsg string) { - -   crudRequests<-cr - -   msg := <-cr.confirm - -   res.Write([]byte(msg)) - -   logIt(logMsg) - -} - - - -func main() { - -   populateClichesList() - - - -   // From now on, this gorountine alone accesses the clichesList. - -   crudRequests = make(chan *crudRequest, 8) - -   go func() { // resource manager - -      for { - -         select { - -         case req := <-crudRequests: - -         if req.verb == GETALL { - -            req.confirm<-readAll() - -         } else if req.verb == GETONE { - -            req.confirm<-readOne(req.id) - -         } else if req.verb == POST { - -            req.confirm<-addPair(req.cp) - -         } else if req.verb == PUT { - -            req.confirm<-editPair(req.id, req.cliche, req.counter) - -         } else if req.verb == DELETE { - -            req.confirm<-deletePair(req.id) - -         } - -      } - -   }() - -   startServer() - -} - - - -func startServer() { - -   router := mux.NewRouter() - - - -   // Dispatch map for CRUD operations. - -   router.HandleFunc("/", ClichesAll).Methods("GET") - -   router.HandleFunc("/cliches", ClichesAll).Methods("GET") - -   router.HandleFunc("/cliches/{id:[0-9]+}", ClichesOne).Methods("GET") - - - -   router.HandleFunc("/cliches", ClichesCreate).Methods("POST") - -   router.HandleFunc("/cliches/{id:[0-9]+}", ClichesEdit).Methods("PUT") - -   router.HandleFunc("/cliches/{id:[0-9]+}", ClichesDelete).Methods("DELETE") - - - -   http.Handle("/", router) // enable the router - - - -   // Start the server. - -   port := ":8888" - -   fmt.Println("\nListening on port " + port) - -   http.ListenAndServe(port, router); // mux.Router now in play - -} - - - -// Return entire list to requester. - -func readAll() string { - -   msg := "\n" - -   for _, cliche := range clichesList { - -      next := strconv.Itoa(cliche.Id) + ": " + cliche.Cliche + "  " + cliche.Counter + "\n" - -      msg += next - -   } - -   return msg - -} - - - -// Return specified clichePair to requester. - -func readOne(id int) string { - -   msg := "\n" + "Bad Id: " + strconv.Itoa(id) + "\n" - - - -   index := findCliche(id) - -   if index >= 0 { - -      cliche := clichesList[index] - -      msg = "\n" + strconv.Itoa(id) + ": " + cliche.Cliche + "  " + cliche.Counter + "\n" - -   } - -   return msg - -} - - - -// Create a new clichePair and add to list - -func addPair(cp *clichePair) string { - -   cp.Id = masterId - -   masterId++ - -   clichesList = append(clichesList, cp) - -   return "\nCreated: " + cp.Cliche + " " + cp.Counter + "\n" - -} - - - -// Edit an existing clichePair - -func editPair(id int, cliche string, counter string) string { - -   msg := "\n" + "Bad Id: " + strconv.Itoa(id) + "\n" - -   index := findCliche(id) - -   if index >= 0 { - -      clichesList[index].Cliche = cliche - -      clichesList[index].Counter = counter - -      msg = "\nCliche edited: " + cliche + " " + counter + "\n" - -   } - -   return msg - -} - - - -// Delete a clichePair - -func deletePair(id int) string { - -   idStr := strconv.Itoa(id) - -   msg := "\n" + "Bad Id: " + idStr + "\n" - -   index := findCliche(id) - -   if index >= 0 { - -      clichesList = append(clichesList[:index], clichesList[index + 1:]...) - -      msg = "\nCliche " + idStr + " deleted\n" - -   } - -   return msg - -} - - - -//*** utility functions - -func findCliche(id int) int { - -   for i := 0; i < len(clichesList); i++ { - -      if id == clichesList[i].Id { - -         return i; - -      } - -   } - -   return -1 // not found - -} - - - -func getIdFromRequest(req *http.Request) int { - -   vars := mux.Vars(req) - -   id, _ := strconv.Atoi(vars["id"]) - -   return id - -} - - - -func getDataFromRequest(req *http.Request) (string, string) { - -   // Extract the user-provided data for the new clichePair - -   req.ParseForm() - -   form := req.Form - -   cliche := form["cliche"][0]    // 1st and only member of a list - -   counter := form["counter"][0]  // ditto - -   return cliche, counter - -} - - - -func logIt(msg string) { - -   fmt.Println(msg) - -} - - - -func populateClichesList() { - -   var cliches = []string { - -      "Out of sight, out of mind.", - -      "A penny saved is a penny earned.", - -      "He who hesitates is lost.", - -   } - -   var counterCliches = []string { - -      "Absence makes the heart grow fonder.", - -      "Penny-wise and dollar-foolish.", - -      "Look before you leap.", - -   } - - - -   for i := 0; i < len(cliches); i++ { - -      cp := new(clichePair) - -      cp.Id = masterId - -      masterId++ - -      cp.Cliche = cliches[i] - -      cp.Counter = counterCliches[i] - -      clichesList = append(clichesList, cp) - -   } - -} - -``` - -To focus on request routing and validation, the crud app does not use HTML pages as responses to requests. Instead, requests result in plaintext response messages: A list of the cliche pairs is the response to a GET request, confirmation that a new cliche pair has been added to the list is a response to a POST request, and so on. This simplification makes it easy to test the app, in particular, the `gorilla/mux` components, with a command-line utility such as [curl][1]. - -The `gorilla/mux` package can be installed from [GitHub][2]. The crud app runs indefinitely; hence, it should be terminated with a Control-C or equivalent. The code for the crud app, together with a README and sample curl tests, is available on [my website][3]. - -### 2\. Request routing - -The `mux.Router` extends REST-style routing, which gives equal weight to the HTTP method (e.g., GET) and the URI or path at the end of a URL (e.g., /cliches). The URI serves as the noun for the HTTP verb (method). For example, in an HTTP request a startline such as -``` -GET /cliches - -``` - -means get all of the cliche pairs, whereas a startline such as -``` -POST /cliches - -``` - -means create a cliche pair from data in the HTTP body. - -In the crud web app, there are five functions that act as request handlers for five variations of an HTTP request: -``` -ClichesAll(...)    # GET: get all of the cliche pairs - -ClichesOne(...)    # GET: get a specified cliche pair - -ClichesCreate(...) # POST: create a new cliche pair - -ClichesEdit(...)   # PUT: edit an existing cliche pair - -ClichesDelete(...) # DELETE: delete a specified cliche pair - -``` - -Each function takes two arguments: an `http.ResponseWriter` for sending a response back to the requester, and a pointer to an `http.Request`, which encapsulates information from the underlying HTTP request. The `gorilla/mux` package makes it easy to register these request handlers with the web server, and to perform regex-based validation. - -The `startServer` function in the crud app registers the request handlers. Consider this pair of registrations, with `router` as a `mux.Router` instance: -``` -router.HandleFunc("/", ClichesAll).Methods("GET") - -router.HandleFunc("/cliches", ClichesAll).Methods("GET") - -``` - -These statements mean that a GET request for either the single slash / or /cliches should be routed to the `ClichesAll` function, which then handles the request. For example, the curl request (with % as the command-line prompt) -``` -% curl --request GET localhost:8888/ - -``` - -produces this response: -``` -1: Out of sight, out of mind.  Absence makes the heart grow fonder. - -2: A penny saved is a penny earned.  Penny-wise and dollar-foolish. - -3: He who hesitates is lost.  Look before you leap. - -``` - -The three cliche pairs are the initial data in the crud app. - -In this pair of registration statements -``` -router.HandleFunc("/cliches", ClichesAll).Methods("GET") - -router.HandleFunc("/cliches", ClichesCreate).Methods("POST") - -``` - -the URI is the same (/cliches) but the verbs differ: GET in the first case, and POST in the second. This registration exemplifies REST-style routing because the difference in the verbs alone suffices to dispatch the requests to two different handlers. - -More than one HTTP method is allowed in a registration, although this strains the spirit of REST-style routing: -``` -router.HandleFunc("/cliches", DoItAll).Methods("POST", "GET") - -``` - -HTTP requests can be routed on features besides the verb and the URI. For example, the registration -``` -router.HandleFunc("/cliches", ClichesCreate).Schemes("https").Methods("POST") - -``` - -requires HTTPS access for a POST request to create a new cliche pair. In similar fashion, a registration might require a request to have a specified HTTP header element (e.g., an authentication credential). - -### 3\. Request validation - -The `gorilla/mux` package takes an easy, intuitive approach to request validation through regular expressions. Consider this request handler for a get one operation: -``` -router.HandleFunc("/cliches/{id:[0-9]+}", ClichesOne).Methods("GET") - -``` - -This registration rules out HTTP requests such as -``` -% curl --request GET localhost:8888/cliches/foo - -``` - -because foo is not a decimal numeral. The request results in the familiar 404 (Not Found) status code. Including the regex pattern in this handler registration ensures that the `ClichesOne` function is called to handle a request only if the request URI ends with a decimal integer value: -``` -% curl --request GET localhost:8888/cliches/3  # ok - -``` - -As a second example, consider the request -``` -% curl --request PUT --data "..." localhost:8888/cliches - -``` - -This request results in a status code of 405 (Bad Method) because the /cliches URI is registered, in the crud app, only for GET and POST requests. A PUT request, like a GET one request, must include a numeric id at the end of the URI: -``` -router.HandleFunc("/cliches/{id:[0-9]+}", ClichesEdit).Methods("PUT") - -``` - -### 4\. Concurrency issues - -The `gorilla/mux` router executes each call to a registered request handler as a separate goroutine, which means that concurrency is baked into the package. For example, if there are ten simultaneous requests such as -``` -% curl --request POST --data "..." localhost:8888/cliches - -``` - -then the `mux.Router` launches ten goroutines to execute the `ClichesCreate` handler. - -Of the five request operations GET all, GET one, POST, PUT, and DELETE, the last three alter the requested resource, the shared `clichesList` that houses the cliche pairs. Accordingly, the crudapp needs to guarantee safe concurrency by coordinating access to the `clichesList`. In different but equivalent terms, the crud app must prevent a race condition on the `clichesList`. In a production environment, a database system might be used to store a resource such as the `clichesList`, and safe concurrency then could be managed through database transactions. - -The crud app takes the recommended Go approach to safe concurrency: - - * Only a single goroutine, the resource manager started in the crud app `startServer` function, has access to the `clichesList` once the web server starts listening for requests. - * The request handlers such as `ClichesCreate` and `ClichesAll` send a (pointer to) a `crudRequest` instance to a Go channel (thread-safe by default), and the resource manager alone reads from this channel. The resource manager then performs the requested operation on the `clichesList`. - - - -The safe-concurrency architecture can be sketched as follows: -``` -                 crudRequest                   read/write - -request handlers------------->resource manager------------>clichesList - -``` - -With this architecture, no explicit locking of the `clichesList` is needed because only one goroutine, the resource manager, accesses the `clichesList` once CRUD requests start coming in. - -To keep the crud app as concurrent as possible, it’s essential to have an efficient division of labor between the request handlers, on the one side, and the single resource manager, on the other side. Here, for review, is the `ClichesCreate` request handler: -``` -func ClichesCreate(res http.ResponseWriter, req *http.Request) { - -   cliche, counter := getDataFromRequest(req) - -   cp := new(clichePair) - -   cp.Cliche = cliche - -   cp.Counter = counter - -   cr := &crudRequest{verb: POST, cp: cp, confirm: make(chan string)} - -   completeRequest(cr, res, "create") - -}ClichesCreateres httpResponseWriterreqclichecountergetDataFromRequestreqcpclichePaircpClicheclichecpCountercountercr&crudRequestverbPOSTcpcpconfirmcompleteRequestcrres - -``` - -`ClichesCreate` calls the utility function `getDataFromRequest`, which extracts the new cliche and counter-cliche from the POST request. The `ClichesCreate` function then creates a new `ClichePair`, sets two fields, and creates a `crudRequest` to be sent to the single resource manager. This request includes a confirmation channel, which the resource manager uses to return information back to the request handler. All of the setup work can be done without involving the resource manager because the `clichesList` is not being accessed yet. - -The request handlercalls the utility function, which extracts the new cliche and counter-cliche from the POST request. Thefunction then creates a new, sets two fields, and creates ato be sent to the single resource manager. This request includes a confirmation channel, which the resource manager uses to return information back to the request handler. All of the setup work can be done without involving the resource manager because theis not being accessed yet. - -The `completeRequest` utility function called at the end of the `ClichesCreate` function and the other request handlers -``` -completeRequest(cr, res, "create") // shown above - -``` - -brings the resource manager into play by putting a `crudRequest` into the `crudRequests` channel: -``` -func completeRequest(cr *crudRequest, res http.ResponseWriter, logMsg string) { - -   crudRequests<-cr          // send request to resource manager - -   msg := <-cr.confirm       // await confirmation string - -   res.Write([]byte(msg))    // send confirmation back to requester - -   logIt(logMsg)             // print to the standard output - -} - -``` - -For a POST request, the resource manager calls the utility function `addPair`, which changes the `clichesList` resource: -``` -func addPair(cp *clichePair) string { - -   cp.Id = masterId  // assign a unique ID - -   masterId++        // update the ID counter - -   clichesList = append(clichesList, cp) // update the list - -   return "\nCreated: " + cp.Cliche + " " + cp.Counter + "\n" - -} - -``` - -The resource manager calls similar utility functions for the other CRUD operations. It’s worth repeating that the resource manager is the only goroutine to read or write the `clichesList` once the web server starts accepting requests. - -For web applications of any type, the `gorilla/mux` package provides request routing, request validation, and related services in a straightforward, intuitive API. The crud web app highlights the package’s main features. Give the package a test drive, and you’ll likely be a buyer. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/8/http-request-routing-validation-gorillamux - -作者：[Marty Kalin][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/mkalindepauledu -[1]:https://curl.haxx.se/ -[2]:https://github.com/gorilla/mux -[3]:http://condor.depaul.edu/mkalin diff --git a/sources/tech/20180822 9 flowchart and diagramming tools for Linux.md b/sources/tech/20180822 9 flowchart and diagramming tools for Linux.md index 853cd1b7c3..5729f765d1 100644 --- a/sources/tech/20180822 9 flowchart and diagramming tools for Linux.md +++ b/sources/tech/20180822 9 flowchart and diagramming tools for Linux.md @@ -1,3 +1,5 @@ +translating by cycoe +cycoe 翻译中 9 flowchart and diagramming tools for Linux ====== diff --git a/sources/tech/20180828 An Introduction to Quantum Computing with Open Source Cirq Framework.md b/sources/tech/20180828 An Introduction to Quantum Computing with Open Source Cirq Framework.md deleted file mode 100644 index 8cec20916d..0000000000 --- a/sources/tech/20180828 An Introduction to Quantum Computing with Open Source Cirq Framework.md +++ /dev/null @@ -1,228 +0,0 @@ -An Introduction to Quantum Computing with Open Source Cirq Framework -====== -As the title suggests what we are about to begin discussing, this article is an effort to understand how far we have come in Quantum Computing and where we are headed in the field in order to accelerate scientific and technological research, through an Open Source perspective with Cirq. - -First, we will introduce you to the world of Quantum Computing. We will try our best to explain the basic idea behind the same before we look into how Cirq would be playing a significant role in the future of Quantum Computing. Cirq, as you might have heard of recently, has been breaking news in the field and in this Open Science article, we will try to find out why. - - - -Before we start with what Quantum Computing is, it is essential to get to know about the term Quantum, that is, a [subatomic particle][1] referring to the smallest known entity. The word [Quantum][2] is based on the Latin word Quantus, meaning, “how little”, as described in this short video: - - - -It will be easier for us to understand Quantum Computing by comparing it first to Classical Computing. Classical Computing refers to how today’s conventional computers are designed to work. The device with which you are reading this article right now, can also be referred to as a Classical Computing Device. - -### Classical Computing - -Classical Computing is just another way to describe how a conventional computer works. They work via a binary system, i.e, information is stored using either 1 or 0. Our Classical computers cannot understand any other form. - -In literal terms inside the computer, a transistor can be either on (1) or off (0). Whatever information we provide input to, is translated into 0s and 1s, so that the computer can understand and store that information. Everything is represented only with the help of a combination of 0s and 1s. - - - -### Quantum Computing - -Quantum Computing, on the other hand, does not follow an “on or off” model like Classical Computing. Instead, it can simultaneously handle multiple states of information with help of two phenomena called [superimposition and entanglement][3], thus accelerating computing at a much faster rate and also facilitating greater productivity in information storage. - -Please note that superposition and entanglement are [not the same phenomena][4]. - - - -![][5] - -So, if we have bits in Classical Computing, then in the case of Quantum Computing, we would have qubits (or Quantum bits) instead. To know more about the vast difference between the two, check this [page][6] from where the above pic was obtained for explanation. - -Quantum Computers are not going to replace our Classical Computers. But, there are certain humongous tasks that our Classical Computers will never be able to accomplish and that is when Quantum Computers would prove extremely resourceful. The following video describes the same in detail while also describing how Quantum Computers work: - - - -A comprehensive video on the progress in Quantum Computing so far: - - - -### Noisy Intermediate Scale Quantum - -According to the very recently updated research paper (31st July 2018), the term “Noisy” refers to inaccuracy because of producing an incorrect value caused by imperfect control over qubits. This inaccuracy is why there will be serious limitations on what Quantum devices can achieve in the near term. - -“Intermediate Scale” refers to the size of Quantum Computers which will be available in the next few years, where the number of qubits can range from 50 to a few hundred. 50 qubits is a significant milestone because that’s beyond what can be simulated by [brute force][7] using the most powerful existing digital [supercomputers][8]. Read more in the paper [here][9]. - -With the advent of Cirq, a lot is about to change. - -### What is Cirq? - -Cirq is a python framework for creating, editing, and invoking Noisy Intermediate Scale Quantum (NISQ) circuits that we just talked about. In other words, Cirq can address challenges to improve accuracy and reduce noise in Quantum Computing. - -Cirq does not necessarily require an actual Quantum Computer for execution. Cirq can also use a simulator-like interface to perform Quantum circuit simulations. - -Cirq is gradually grabbing a lot of pace, with one of its first users being [Zapata][10], formed last year by a [group of scientists][11] from Harvard University focused on Quantum Computing. - -### Getting started with Cirq on Linux - -The developers of the Open Source [Cirq library][12] recommend the installation in a [virtual python environment][13] like [virtualenv][14]. The developers’ installation guide for Linux can be found [here][15]. - -However, we successfully installed and tested Cirq directly for Python3 on an Ubuntu 16.04 system via the following steps: - -#### Installing Cirq on Ubuntu - -![Cirq Framework for Quantum Computing in Linux][16] - -First, we would require pip or pip3 to install Cirq. [Pip][17] is a tool recommended for installing and managing Python packages. - -For Python 3.x versions, Pip can be installed with: -``` -sudo apt-get install python3-pip - -``` - -Python3 packages can be installed via: -``` -pip3 install - -``` - -We went ahead and installed the Cirq library with Pip3 for Python3: -``` -pip3 install cirq - -``` - -#### Enabling Plot and PDF generation (optional) - -Optional system dependencies not install-able with pip can be installed with: -``` -sudo apt-get install python3-tk texlive-latex-base latexmk - -``` - - * python3-tk is Python’s own graphic library which enables plotting functionality. - * texlive-latex-base and latexmk enable PDF writing functionality. - - - -Later, we successfully tested Cirq with the following command and code: -``` -python3 -c 'import cirq; print(cirq.google.Foxtail)' - -``` - -We got the resulting output as: - -![][18] - -#### Configuring Pycharm IDE for Cirq - -We also configured a Python IDE [PyCharm on Ubuntu][19] to test the same results: - -Since we installed Cirq for Python3 on our Linux system, we set the path to the project interpreter in the IDE settings to be: -``` -/usr/bin/python3 - -``` - -![][20] - -In the output above, you can note that the path to the project interpreter that we just set, is shown along with the path to the test program file (test.py). An exit code of 0 shows that the program has finished executing successfully without errors. - -So, that’s a ready-to-use IDE environment where you can import the Cirq library to start programming with Python and simulate Quantum circuits. - -#### Get started with Cirq - -A good place to start are the [examples][21] that have been made available on Cirq’s Github page. - -The developers have included this [tutorial][22] on GitHub to get started with learning Cirq. If you are serious about learning Quantum Computing, they recommend an excellent book called [“Quantum Computation and Quantum Information” by Nielsen and Chuang][23]. - -#### OpenFermion-Cirq - -[OpenFermion][24] is an open source library for obtaining and manipulating representations of fermionic systems (including Quantum Chemistry) for simulation on Quantum Computers. Fermionic systems are related to the generation of [fermions][25], which according to [particle physics][26], follow [Fermi-Dirac statistics][27]. - -OpenFermion has been hailed as [a great practice tool][28] for chemists and researchers involved with [Quantum Chemistry][29]. The main focus of Quantum Chemistry is the application of [Quantum Mechanics][30] in physical models and experiments of chemical systems. Quantum Chemistry is also referred to as [Molecular Quantum Mechanics][31]. - -The advent of Cirq has now made it possible for OpenFermion to extend its functionality by providing routines and tools for using Cirq to compile and compose circuits for Quantum simulation algorithms. - -#### Google Bristlecone - -On March 5, 2018, Google presented [Bristlecone][32], their new Quantum processor, at the annual [American Physical Society meeting][33] in Los Angeles. The [gate-based superconducting system][34] provides a test platform for research into [system error rates][35] and [scalability][36] of Google’s [qubit technology][37], along-with applications in Quantum [simulation][38], [optimization][39], and [machine learning.][40] - -In the near future, Google wants to make its 72 qubit Bristlecone Quantum processor [cloud accessible][41]. Bristlecone will gradually become quite capable to perform a task that a Classical Supercomputer would not be able to complete in a reasonable amount of time. - -Cirq would make it easier for researchers to directly write programs for Bristlecone on the cloud, serving as a very convenient interface for real-time Quantum programming and testing. - -Cirq will allow us to: - - * Fine tune control over Quantum circuits, - * Specify [gate][42] behavior using native gates, - * Place gates appropriately on the device & - * Schedule the timing of these gates. - - - -### The Open Science Perspective on Cirq - -As we all know Cirq is Open Source on GitHub, its addition to the Open Source Scientific Communities, especially those which are focused on Quantum Research, can now efficiently collaborate to solve the current challenges in Quantum Computing today by developing new ways to reduce error rates and improve accuracy in the existing Quantum models. - -Had Cirq not followed an Open Source model, things would have definitely been a lot more challenging. A great initiative would have been missed out and we would not have been one step closer in the field of Quantum Computing. - -### Summary - -To summarize in the end, we first introduced you to the concept of Quantum Computing by comparing it to existing Classical Computing techniques followed by a very important video on recent developmental updates in Quantum Computing since last year. We then briefly discussed Noisy Intermediate Scale Quantum, which is what Cirq is specifically built for. - -We saw how we can install and test Cirq on an Ubuntu system. We also tested the installation for usability on an IDE environment with some resources to get started to learn the concept. - -Finally, we also saw two examples of how Cirq would be an essential advantage in the development of research in Quantum Computing, namely OpenFermion and Bristlecone. We concluded the discussion by highlighting some thoughts on Cirq with an Open Science Perspective. - -We hope we were able to introduce you to Quantum Computing with Cirq in an easy to understand manner. If you have any feedback related to the same, please let us know in the comments section. Thank you for reading and we look forward to see you in our next Open Science article. - --------------------------------------------------------------------------------- - -via: https://itsfoss.com/qunatum-computing-cirq-framework/ - -作者：[Avimanyu Bandyopadhyay][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://itsfoss.com/author/avimanyu/ -[1]:https://en.wikipedia.org/wiki/Subatomic_particle -[2]:https://en.wikipedia.org/wiki/Quantum -[3]:https://www.clerro.com/guide/491/quantum-superposition-and-entanglement-explained -[4]:https://physics.stackexchange.com/questions/148131/can-quantum-entanglement-and-quantum-superposition-be-considered-the-same-phenom -[5]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/08/bit-vs-qubit.jpg -[6]:http://www.rfwireless-world.com/Terminology/Difference-between-Bit-and-Qubit.html -[7]:https://en.wikipedia.org/wiki/Proof_by_exhaustion -[8]:https://www.explainthatstuff.com/how-supercomputers-work.html -[9]:https://arxiv.org/abs/1801.00862 -[10]:https://www.xconomy.com/san-francisco/2018/07/19/google-partners-with-zapata-on-open-source-quantum-computing-effort/ -[11]:https://www.zapatacomputing.com/about/ -[12]:https://github.com/quantumlib/Cirq -[13]:https://itsfoss.com/python-setup-linux/ -[14]:https://virtualenv.pypa.io -[15]:https://cirq.readthedocs.io/en/latest/install.html#installing-on-linux -[16]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/08/cirq-framework-linux.jpeg -[17]:https://pypi.org/project/pip/ -[18]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/08/cirq-test-output.jpg -[19]:https://itsfoss.com/install-pycharm-ubuntu/ -[20]:https://4bds6hergc-flywheel.netdna-ssl.com/wp-content/uploads/2018/08/cirq-tested-on-pycharm.jpg -[21]:https://github.com/quantumlib/Cirq/tree/master/examples -[22]:https://github.com/quantumlib/Cirq/blob/master/docs/tutorial.md -[23]:http://mmrc.amss.cas.cn/tlb/201702/W020170224608149940643.pdf -[24]:http://openfermion.org -[25]:https://en.wikipedia.org/wiki/Fermion -[26]:https://en.wikipedia.org/wiki/Particle_physics -[27]:https://en.wikipedia.org/wiki/Fermi-Dirac_statistics -[28]:https://phys.org/news/2018-03-openfermion-tool-quantum-coding.html -[29]:https://en.wikipedia.org/wiki/Quantum_chemistry -[30]:https://en.wikipedia.org/wiki/Quantum_mechanics -[31]:https://ocw.mit.edu/courses/chemical-engineering/10-675j-computational-quantum-mechanics-of-molecular-and-extended-systems-fall-2004/lecture-notes/ -[32]:https://techcrunch.com/2018/03/05/googles-new-bristlecone-processor-brings-it-one-step-closer-to-quantum-supremacy/ -[33]:http://meetings.aps.org/Meeting/MAR18/Content/3475 -[34]:https://en.wikipedia.org/wiki/Superconducting_quantum_computing -[35]:https://en.wikipedia.org/wiki/Quantum_error_correction -[36]:https://en.wikipedia.org/wiki/Scalability -[37]:https://research.googleblog.com/2015/03/a-step-closer-to-quantum-computation.html -[38]:https://research.googleblog.com/2017/10/announcing-openfermion-open-source.html -[39]:https://research.googleblog.com/2016/06/quantum-annealing-with-digital-twist.html -[40]:https://arxiv.org/abs/1802.06002 -[41]:https://www.computerworld.com.au/article/644051/google-launches-quantum-framework-cirq-plans-bristlecone-cloud-move/ -[42]:https://en.wikipedia.org/wiki/Logic_gate diff --git a/sources/tech/20180911 Know Your Storage- Block, File - Object.md b/sources/tech/20180911 Know Your Storage- Block, File - Object.md deleted file mode 100644 index 24f179d9d5..0000000000 --- a/sources/tech/20180911 Know Your Storage- Block, File - Object.md +++ /dev/null @@ -1,62 +0,0 @@ -Know Your Storage: Block, File & Object -====== - -![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/block2_1920.jpg?itok=s1y6RLhT) - -Dealing with the tremendous amount of data generated today presents a big challenge for companies who create or consume such data. It’s a challenge for tech companies that are dealing with related storage issues. - -“Data is growing exponentially each year, and we find that the majority of data growth is due to increased consumption and industries adopting transformational projects to expand value. Certainly, the Internet of Things (IoT) has contributed greatly to data growth, but the key challenge for software-defined storage is how to address the use cases associated with data growth,” said Michael St. Jean, principal product marketing manager, Red Hat Storage. - -Every challenge is an opportunity. “The deluge of data being generated by old and new sources today is certainly presenting us with opportunities to meet our customers escalating needs in the areas of scale, performance, resiliency, and governance,” said Tad Brockway, General Manager for Azure Storage, Media and Edge. - -### Trinity of modern software-defined storage - -There are three different kinds of storage solutions -- block, file, and object -- each serving a different purpose while working with the others. - -Block storage is the oldest form of data storage, where data is stored in fixed-length blocks or chunks of data. Block storage is used in enterprise storage environments and usually is accessed using Fibre Channel or iSCSI interface. “Block storage requires an application to map where the data is stored on the storage device,” according to SUSE’s Larry Morris, Sr. Product Manager, Software Defined Storage. - -Block storage is virtualized in storage area network and software defined storage systems, which are abstracted logical devices that reside on a shared hardware infrastructure and are created and presented to the host operating system of a server, virtual server, or hypervisor via protocols like SCSI, SATA, SAS, FCP, FCoE, or iSCSI. - -“Block storage splits a single storage volume (like a virtual or cloud storage node, or a good old fashioned hard disk) into individual instances known as blocks,” said St. Jean. - -Each block exists independently and can be formatted with its own data transfer protocol and operating system — giving users complete configuration autonomy. Because block storage systems aren’t burdened with the same investigative file-finding duties as the file storage systems, block storage is a faster storage system. Pairing that speed with configuration flexibility makes block storage ideal for raw server storage or rich media databases. - -Block storage can be used to host operating systems, applications, databases, entire virtual machines and containers. Traditionally, block storage can only be accessed by individual machine, or machines in a cluster, to which it has been presented. - -### File-based storage - -File-based storage uses a filesystem to map where the data is stored on the storage device. It’s a dominant technology used on direct- and networked-attached storage system, and it takes care of two things: organizing data and representing it to users. “With file storage, data is arranged on the server side in the exact same format as the clients see it. This allows the user to request a file by some unique identifier — like a name, location, or URL — which is communicated to the storage system using specific data transfer protocols,” said St. Jean. - -The result is a type of hierarchical file structure that can be navigated from top to bottom. File storage is layered on top of block storage, allowing users to see and access data as files and folders, but restricting access to the blocks that stand up those files and folders. - -“File storage is typically represented by shared filesystems like NFS and CIFS/SMB that can be accessed by many servers over an IP network. Access can be controlled at a file, directory, and export level via user and group permissions. File storage can be used to store files needed by multiple users and machines, application binaries, databases, virtual machines, and can be used by containers,” explained Brockway. - -### Object storage - -Object storage is the newest form of data storage, and it provides a repository for unstructured data which separates the content from the indexing and allows the concatenation of multiple files into an object. An object is a piece of data paired with any associated metadata that provides context about the bytes contained within the object (things like how old or big the data is). Those two things together — the data and metadata — make an object. - -One advantage of object storage is the unique identifier associated with each piece of data. Accessing the data involves using the unique identifier and does not require the application or user to know where the data is actually stored. Object data is accessed through APIs. - -“The data stored in objects is uncompressed and unencrypted, and the objects themselves are arranged in object stores (a central repository filled with many other objects) or containers (a package that contains all of the files an application needs to run). Objects, object stores, and containers are very flat in nature — compared to the hierarchical structure of file storage systems — which allow them to be accessed very quickly at huge scale,” explained St. Jean. - -Object stores can scale to many petabytes to accommodate the largest datasets and are a great choice for images, audio, video, logs, backups, and data used by analytics services. - -### Conclusion - -Now you know about the various types of storage and how they are used. Stay tuned to learn more about software-defined storage as we examine the topic in the future. - -Join us at [Open Source Summit + Embedded Linux Conference Europe][1] in Edinburgh, UK on October 22-24, 2018, for 100+ sessions on Linux, Cloud, Containers, AI, Community, and more. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/blog/2018/9/know-your-storage-block-file-object - -作者：[Swapnil Bhartiya][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://www.linux.com/users/arnieswap -[1]: https://events.linuxfoundation.org/events/elc-openiot-europe-2018/ diff --git a/sources/tech/20180912 How to turn on an LED with Fedora IoT.md b/sources/tech/20180912 How to turn on an LED with Fedora IoT.md deleted file mode 100644 index 007cfc27ab..0000000000 --- a/sources/tech/20180912 How to turn on an LED with Fedora IoT.md +++ /dev/null @@ -1,201 +0,0 @@ -How to turn on an LED with Fedora IoT -====== - -![](https://fedoramagazine.org/wp-content/uploads/2018/08/LED-IoT-816x345.jpg) - -Do you enjoy running Fedora, containers, and have a Raspberry Pi? What about using all three together to play with LEDs? This article introduces Fedora IoT and shows you how to install a preview image on a Raspberry Pi. You’ll also learn how to interact with GPIO in order to light up an LED. - -### What is Fedora IoT? - -Fedora IoT is one of the current Fedora Project objectives, with a plan to become a full Fedora Edition. The result will be a system that runs on ARM (aarch64 only at the moment) devices such as the Raspberry Pi, as well as on the x86_64 architecture. - -![][1] - -Fedora IoT is based on OSTree, like [Fedora Silverblue][2] and the former [Atomic Host][3]. - -### Download and install Fedora IoT - -The official Fedora IoT images are coming with the Fedora 29 release. However, in the meantime you can download a [Fedora 28-based image][4] for this experiment. - -You have two options to install the system: either flash the SD card using a dd command, or use a fedora-arm-installer tool. The Fedora Wiki offers more information about [setting up a physical device][5] for IoT. Also, remember that you might need to resize the third partition. - -Once you insert the SD card into the device, you’ll need to complete the installation by creating a user. This step requires either a serial connection, or a HDMI display with a keyboard to interact with the device. - -When the system is installed and ready, the next step is to configure a network connection. Log in to the system with the user you have just created choose one of the following options: - - * If you need to configure your network manually, run a command similar to the following. Remember to use the right addresses for your network: -``` - $ nmcli connection add con-name cable ipv4.addresses \ - 192.168.0.10/24 ipv4.gateway 192.168.0.1 \ - connection.autoconnect true ipv4.dns "8.8.8.8,1.1.1.1" \ - type ethernet ifname eth0 ipv4.method manual - -``` - - * If there’s a DHCP service on your network, run a command like this: - -``` - $ nmcli con add type ethernet con-name cable ifname eth0 -``` - - - - -### **The GPIO interface in Fedora** - -Many tutorials about GPIO on Linux focus on a legacy GPIO sysfis interface. This interface is deprecated, and the upstream Linux kernel community plan to remove it completely, due to security and other issues. - -The Fedora kernel is already compiled without this legacy interface, so there’s no /sys/class/gpio on the system. This tutorial uses a new character device /dev/gpiochipN provided by the upstream kernel. This is the current way of interacting with GPIO. - -To interact with this new device, you need to use a library and a set of command line interface tools. The common command line tools such as echo or cat won’t work with this device. - -You can install the CLI tools by installing the libgpiod-utils package. A corresponding Python library is provided by the python3-libgpiod package. - -### **Creating a container with Podman** - -[Podman][6] is a container runtime with a command line interface similar to Docker. The big advantage of Podman is it doesn’t run any daemon in the background. That’s especially useful for devices with limited resources. Podman also allows you to start containerized services with systemd unit files. Plus, it has many additional features. - -We’ll create a container in these two steps: - - 1. Create a layered image containing the required packages. - 2. Create a new container starting from our image. - - - -First, create a file Dockerfile with the content below. This tells podman to build an image based on the latest Fedora image available in the registry. Then it updates the system inside and installs some packages: - -``` -FROM fedora:latest -RUN  dnf -y update -RUN  dnf -y install libgpiod-utils python3-libgpiod - -``` - -You have created a build recipe of a container image based on the latest Fedora with updates, plus packages to interact with GPIO. - -Now, run the following command to build your base image: - -``` -$ sudo podman build --tag fedora:gpiobase -f ./Dockerfile - -``` - -You have just created your custom image with all the bits in place. You can play with this base container images as many times as you want without installing the packages every time you run it. - -### Working with Podman - -To verify the image is present, run the following command: - -``` -$ sudo podman images -REPOSITORY                 TAG        IMAGE ID       CREATED          SIZE -localhost/fedora           gpiobase   67a2b2b93b4b   10 minutes ago  488MB -docker.io/library/fedora   latest     c18042d7fac6   2 days ago     300MB - -``` - -Now, start the container and do some actual experiments. Containers are normally isolated and don’t have an access to the host system, including the GPIO interface. Therefore, you need to mount it inside while starting the container. To do this, use the –device option in the following command: - -``` -$ sudo podman run -it --name gpioexperiment --device=/dev/gpiochip0 localhost/fedora:gpiobase /bin/bash - -``` - -You are now inside the running container. Before you move on, here are some more container commands. For now, exit the container by typing exit or pressing **Ctrl+D**. - -To list the the existing containers, including those not currently running, such as the one you just created, run: - -``` -$ sudo podman container ls -a -CONTAINER ID   IMAGE             COMMAND     CREATED          STATUS                              PORTS   NAMES -64e661d5d4e8   localhost/fedora:gpiobase   /bin/bash 37 seconds ago Exited (0) Less than a second ago           gpioexperiment - -``` - -To create a new container, run this command: - -``` -$ sudo podman run -it --name newexperiment --device=/dev/gpiochip0 localhost/fedora:gpiobase /bin/bash - -``` - -Delete it with the following command: - -``` -$ sudo podman rm newexperiment - -``` - -### **Turn on an LED** - -Now you can use the container you already created. If you exited from the container, start it again with this command: - -``` -$ sudo podman start -ia gpioexperiment - -``` - -As already discussed, you can use the CLI tools provided by the libgpiod-utils package in Fedora. To list the available GPIO chips, run: - -``` -$ gpiodetect -gpiochip0 [pinctrl-bcm2835] (54 lines) - -``` - -To get the list of the lines exposed by a specific chip, run: - -``` -$ gpioinfo gpiochip0 - -``` - -Notice there’s no correlation between the number of physical pins and the number of lines printed by the previous command. What’s important is the BCM number, as shown on [pinout.xyz][7]. It is not advised to play with the lines that don’t have a corresponding BCM number. - -Now, connect an LED to the physical pin 40, that is BCM 21. Remember: the shorter leg of the LED (the negative leg, called the cathode) must be connected to a GND pin of the Raspberry Pi with a 330 ohm resistor, and the long leg (the anode) to the physical pin 40. - -To turn the LED on, run the following command. It will stay on until you press **Ctrl+C** : - -``` -$ gpioset --mode=wait gpiochip0 21=1 - -``` - -To light it up for a certain period of time, add the -b (run in the background) and -s NUM (how many seconds) parameters, as shown below. For example, to light the LED for 5 seconds, run: - -``` -$ gpioset -b -s 5 --mode=time gpiochip0 21=1 - -``` - -Another useful command is gpioget. It gets the status of a pin (high or low), and can be useful to detect buttons and switches. - -![Closeup of LED connection with GPIO][8] - -### **Conclusion** - -You can also play with LEDs using Python — [there are some examples here][9]. And you can also use the i2c devices inside the container as well. In addition, Podman is not strictly related to this Fedora edition. You can install it on any existing Fedora Edition, or try it on the two new OSTree-based systems in Fedora: [Fedora Silverblue][2] and [Fedora CoreOS][10]. - - --------------------------------------------------------------------------------- - -via: https://fedoramagazine.org/turnon-led-fedora-iot/ - -作者：[Alessio Ciregia][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: http://alciregi.id.fedoraproject.org/ -[1]: https://fedoramagazine.org/wp-content/uploads/2018/08/oled-1024x768.png -[2]: https://teamsilverblue.org/ -[3]: https://www.projectatomic.io/ -[4]: https://kojipkgs.fedoraproject.org/compose/iot/latest-Fedora-IoT-28/compose/IoT/ -[5]: https://fedoraproject.org/wiki/InternetOfThings/GettingStarted#Setting_up_a_Physical_Device -[6]: https://github.com/containers/libpod -[7]: https://pinout.xyz/ -[8]: https://fedoramagazine.org/wp-content/uploads/2018/08/breadboard-1024x768.png -[9]: https://github.com/brgl/libgpiod/tree/master/bindings/python/examples -[10]: https://coreos.fedoraproject.org/ diff --git a/sources/tech/20180914 A day in the life of a log message.md b/sources/tech/20180914 A day in the life of a log message.md index 8d60ec9fe6..cc6ebd0f5b 100644 --- a/sources/tech/20180914 A day in the life of a log message.md +++ b/sources/tech/20180914 A day in the life of a log message.md @@ -1,3 +1,4 @@ +Ryze-Borgia is translating A day in the life of a log message ====== diff --git a/sources/tech/20180928 Quiet log noise with Python and machine learning.md b/sources/tech/20180928 Quiet log noise with Python and machine learning.md index 79894775ed..f1fe2f1b7f 100644 --- a/sources/tech/20180928 Quiet log noise with Python and machine learning.md +++ b/sources/tech/20180928 Quiet log noise with Python and machine learning.md @@ -1,5 +1,3 @@ -translating by Flowsnow - Quiet log noise with Python and machine learning ====== diff --git a/sources/tech/20181003 Manage NTP with Chrony.md b/sources/tech/20181003 Manage NTP with Chrony.md new file mode 100644 index 0000000000..aaec88da26 --- /dev/null +++ b/sources/tech/20181003 Manage NTP with Chrony.md @@ -0,0 +1,291 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Manage NTP with Chrony) +[#]: via: (https://opensource.com/article/18/12/manage-ntp-chrony) +[#]: author: (David Both https://opensource.com/users/dboth) + +Manage NTP with Chrony +====== +Chronyd is a better choice for most networks than ntpd for keeping computers synchronized with the Network Time Protocol. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/clocks_time.png?itok=_ID09GDk) + +> "Does anybody really know what time it is? Does anybody really care?" +> – [Chicago][1], 1969 + +Perhaps that rock group didn't care what time it was, but our computers do need to know the exact time. Timekeeping is very important to computer networks. In banking, stock markets, and other financial businesses, transactions must be maintained in the proper order, and exact time sequences are critical for that. For sysadmins and DevOps professionals, it's easier to follow the trail of email through a series of servers or to determine the exact sequence of events using log files on geographically dispersed hosts when exact times are kept on the computers in question. + +I used to work at an organization that received over 20 million emails per day and had four servers just to accept and do a basic filter on the incoming flood of email. From there, emails were sent to one of four other servers to perform more complex anti-spam assessments, then they were delivered to one of several additional servers where the emails were placed in the correct inboxes. At each layer, the emails would be sent to one of the next-level servers, selected only by the randomness of round-robin DNS. Sometimes we had to trace a new message through the system until we could determine where it "got lost," according to the pointy-haired bosses. We had to do this with frightening regularity. + +Most of that email turned out to be spam. Some people actually complained that their [joke, cat pic, recipe, inspirational saying, or other-strange-email]-of-the-day was missing and asked us to find it. We did reject those opportunities. + +Our email and other transactional searches were aided by log entries with timestamps that—today—can resolve down to the nanosecond in even the slowest of modern Linux computers. In very high-volume transaction environments, even a few microseconds of difference in the system clocks can mean sorting thousands of transactions to find the correct one(s). + +### The NTP server hierarchy + +Computers worldwide use the [Network Time Protocol][2] (NTP) to synchronize their times with internet standard reference clocks via a hierarchy of NTP servers. The primary servers are at stratum 1, and they are connected directly to various national time services at stratum 0 via satellite, radio, or even modems over phone lines. The time service at stratum 0 may be an atomic clock, a radio receiver tuned to the signals broadcast by an atomic clock, or a GPS receiver using the highly accurate clock signals broadcast by GPS satellites. + +To prevent time requests from time servers lower in the hierarchy (i.e., with a higher stratum number) from overwhelming the primary reference servers, there are several thousand public NTP stratum 2 servers that are open and available for anyone to use. Many organizations with large numbers of hosts that need an NTP server will set up their own time servers so that only one local host accesses the stratum 2 time servers, then they configure the remaining network hosts to use the local time server which, in my case, is a stratum 3 server. + +### NTP choices + +The original NTP daemon, **ntpd** , has been joined by a newer one, **chronyd**. Both keep the local host's time synchronized with the time server. Both services are available, and I have seen nothing to indicate that this will change anytime soon. + +Chrony has features that make it the better choice for most environments for the following reasons: + + * Chrony can synchronize to the time server much faster than NTP. This is good for laptops or desktops that don't run constantly. + + * It can compensate for fluctuating clock frequencies, such as when a host hibernates or enters sleep mode, or when the clock speed varies due to frequency stepping that slows clock speeds when loads are low. + + * It handles intermittent network connections and bandwidth saturation. + + * It adjusts for network delays and latency. + + * After the initial time sync, Chrony never steps the clock. This ensures stable and consistent time intervals for system services and applications. + + * Chrony can work even without a network connection. In this case, the local host or server can be updated manually. + + + + +The NTP and Chrony RPM packages are available from standard Fedora repositories. You can install both and switch between them, but modern Fedora, CentOS, and RHEL releases have moved from NTP to Chrony as their default time-keeping implementation. I have found that Chrony works well, provides a better interface for the sysadmin, presents much more information, and increases control. + +Just to make it clear, NTP is a protocol that is implemented with either NTP or Chrony. If you'd like to know more, read this [comparison between NTP and Chrony][3] as implementations of the NTP protocol. + +This article explains how to configure Chrony clients and servers on a Fedora host, but the configuration for CentOS and RHEL current releases works the same. + +### Chrony structure + +The Chrony daemon, **chronyd** , runs in the background and monitors the time and status of the time server specified in the **chrony.conf** file. If the local time needs to be adjusted, **chronyd** does it smoothly without the programmatic trauma that would occur if the clock were instantly reset to a new time. + +Chrony's **chronyc** tool allows someone to monitor the current status of Chrony and make changes if necessary. The **chronyc** utility can be used as a command that accepts subcommands, or it can be used as an interactive text-mode program. This article will explain both uses. + +### Client configuration + +The NTP client configuration is simple and requires little or no intervention. The NTP server can be defined during the Linux installation or provided by the DHCP server at boot time. The default **/etc/chrony.conf** file (shown below in its entirety) requires no intervention to work properly as a client. For Fedora, Chrony uses the Fedora NTP pool, and CentOS and RHEL have their own NTP server pools. Like many Red Hat-based distributions, the configuration file is well commented. + +``` +# Use public servers from the pool.ntp.org project. +# Please consider joining the pool (http://www.pool.ntp.org/join.html). +pool 2.fedora.pool.ntp.org iburst + +# Record the rate at which the system clock gains/losses time. +driftfile /var/lib/chrony/drift + +# Allow the system clock to be stepped in the first three updates +# if its offset is larger than 1 second. +makestep 1.0 3 + +# Enable kernel synchronization of the real-time clock (RTC). + + +# Enable hardware timestamping on all interfaces that support it. +#hwtimestamp * + +# Increase the minimum number of selectable sources required to adjust +# the system clock. +#minsources 2 + +# Allow NTP client access from local network. +#allow 192.168.0.0/16 + +# Serve time even if not synchronized to a time source. +#local stratum 10 + +# Specify file containing keys for NTP authentication. +keyfile /etc/chrony.keys + +# Get TAI-UTC offset and leap seconds from the system tz database. +leapsectz right/UTC + +# Specify directory for log files. +logdir /var/log/chrony + +# Select which information is logged. +#log measurements statistics tracking +``` + +Let's look at the current status of NTP on a virtual machine I use for testing. The **chronyc** command, when used with the **tracking** subcommand, provides statistics that report how far off the local system is from the reference server. + +``` +[root@studentvm1 ~]# chronyc tracking +Reference ID    : 23ABED4D (ec2-35-171-237-77.compute-1.amazonaws.com) +Stratum         : 3 +Ref time (UTC)  : Fri Nov 16 16:21:30 2018 +System time     : 0.000645622 seconds slow of NTP time +Last offset     : -0.000308577 seconds +RMS offset      : 0.000786140 seconds +Frequency       : 0.147 ppm slow +Residual freq   : -0.073 ppm +Skew            : 0.062 ppm +Root delay      : 0.041452706 seconds +Root dispersion : 0.022665167 seconds +Update interval : 1044.2 seconds +Leap status     : Normal +[root@studentvm1 ~]# +``` + +The Reference ID in the first line of the result is the server the host is synchronized to—in this case, a stratum 3 reference server that was last contacted by the host at 16:21:30 2018. The other lines are described in the [chronyc(1) man page][4]. + +The **sources** subcommand is also useful because it provides information about the time source configured in **chrony.conf**. + +``` +[root@studentvm1 ~]# chronyc sources +210 Number of sources = 5 +MS Name/IP address         Stratum Poll Reach LastRx Last sample               +=============================================================================== +^+ 192.168.0.51                  3   6   377     0  -2613us[-2613us] +/-   63ms +^+ dev.smatwebdesign.com         3  10   377   28m  -2961us[-3534us] +/-  113ms +^+ propjet.latt.net              2  10   377   465  -1097us[-1085us] +/-   77ms +^* ec2-35-171-237-77.comput>     2  10   377    83  +2388us[+2395us] +/-   95ms +^+ PBX.cytranet.net              3  10   377   507  -1602us[-1589us] +/-   96ms +[root@studentvm1 ~]# +``` + +The first source in the list is the time server I set up for my personal network. The others were provided by the pool. Even though my NTP server doesn't appear in the Chrony configuration file above, my DHCP server provides its IP address for the NTP server. The "S" column—Source State—indicates with an asterisk ( ***** ) the server our host is synced to. This is consistent with the data from the **tracking** subcommand. + +The **-v** option provides a nice description of the fields in this output. + +``` +[root@studentvm1 ~]# chronyc sources -v +210 Number of sources = 5 + +  .-- Source mode  '^' = server, '=' = peer, '#' = local clock. + / .- Source state '*' = current synced, '+' = combined , '-' = not combined, +| /   '?' = unreachable, 'x' = time may be in error, '~' = time too variable. +||                                                 .- xxxx [ yyyy ] +/- zzzz +||      Reachability register (octal) -.           |  xxxx = adjusted offset, +||      Log2(Polling interval) --.      |          |  yyyy = measured offset, +||                                \     |          |  zzzz = estimated error. +||                                 |    |           \ +MS Name/IP address         Stratum Poll Reach LastRx Last sample               +=============================================================================== +^+ 192.168.0.51                  3   7   377    28  -2156us[-2156us] +/-   63ms +^+ triton.ellipse.net            2  10   377    24  +5716us[+5716us] +/-   62ms +^+ lithium.constant.com          2  10   377   351   -820us[ -820us] +/-   64ms +^* t2.time.bf1.yahoo.com         2  10   377   453   -992us[ -965us] +/-   46ms +^- ntp.idealab.com               2  10   377   799  +3653us[+3674us] +/-   87ms +[root@studentvm1 ~]# +``` + +If I wanted my server to be the preferred reference time source for this host, I would add the line below to the **/etc/chrony.conf** file. + +``` +server 192.168.0.51 iburst prefer +``` + +I usually place this line just above the first pool server statement near the top of the file. There is no special reason for this, except I like to keep the server statements together. It would work just as well at the bottom of the file, and I have done that on several hosts. This configuration file is not sequence-sensitive. + +The **prefer** option marks this as the preferred reference source. As such, this host will always be synchronized with this reference source (as long as it is available). We can also use the fully qualified hostname for a remote reference server or the hostname only (without the domain name) for a local reference time source as long as the search statement is set in the **/etc/resolv.conf** file. I prefer the IP address to ensure that the time source is accessible even if DNS is not working. In most environments, the server name is probably the better option, because NTP will continue to work even if the server's IP address changes. + +If you don't have a specific reference source you want to synchronize to, it is fine to use the defaults. + +### Configuring an NTP server with Chrony + +The nice thing about the Chrony configuration file is that this single file configures the host as both a client and a server. To add a server function to our host—it will always be a client, obtaining its time from a reference server—we just need to make a couple of changes to the Chrony configuration, then configure the host's firewall to accept NTP requests. + +Open the **/etc/ ** **chrony****.conf** file in your favorite text editor and uncomment the **local stratum 10** line. This enables the Chrony NTP server to continue to act as if it were connected to a remote reference server if the internet connection fails; this enables the host to continue to be an NTP server to other hosts on the local network. + +Let's restart **chronyd** and track how the service is working for a few minutes. Before we enable our host as an NTP server, we want to test a bit. + +``` +[root@studentvm1 ~]# systemctl restart chronyd ; watch chronyc tracking +``` + +The results should look like this. The **watch** command runs the **chronyc tracking** command every two seconds so we can watch changes occur over time. + +``` +Every 2.0s: chronyc tracking                                           studentvm1: Fri Nov 16 20:59:31 2018 + +Reference ID    : C0A80033 (192.168.0.51) +Stratum         : 4 +Ref time (UTC)  : Sat Nov 17 01:58:51 2018 +System time     : 0.001598277 seconds fast of NTP time +Last offset     : +0.001791533 seconds +RMS offset      : 0.001791533 seconds +Frequency       : 0.546 ppm slow +Residual freq   : -0.175 ppm +Skew            : 0.168 ppm +Root delay      : 0.094823152 seconds +Root dispersion : 0.021242738 seconds +Update interval : 65.0 seconds +Leap status     : Normal +``` + +Notice that my NTP server, the **studentvm1** host, synchronizes to the host at 192.168.0.51, which is my internal network NTP server, at stratum 4. Synchronizing directly to the Fedora pool machines would result in synchronization at stratum 3. Notice also that the amount of error decreases over time. Eventually, it should stabilize with a tiny variation around a fairly small range of error. The size of the error depends upon the stratum and other network factors. After a few minutes, use Ctrl+C to break out of the watch loop. + +To turn our host into an NTP server, we need to allow it to listen on the local network. Uncomment the following line to allow hosts on the local network to access our NTP server. + +``` +# Allow NTP client access from local network. +allow 192.168.0.0/16 +``` + +Note that the server can listen for requests on any local network it's attached to. The IP address in the "allow" line is just intended for illustrative purposes. Be sure to change the IP network and subnet mask in that line to match your local network's. + +Restart **chronyd**. + +``` +[root@studentvm1 ~]# systemctl restart chronyd +``` + +To allow other hosts on your network to access this server, configure the firewall to allow inbound UDP packets on port 123. Check your firewall's documentation to find out how to do that. + +### Testing + +Your host is now an NTP server. You can test it with another host or a VM that has access to the network on which the NTP server is listening. Configure the client to use the new NTP server as the preferred server in the **/etc/chrony.conf** file, then monitor that client using the **chronyc** tools we used above. + +### Chronyc as an interactive tool + +As I mentioned earlier, **chronyc** can be used as an interactive command tool. Simply run the command without a subcommand and you get a **chronyc** command prompt. + +``` +[root@studentvm1 ~]# chronyc +chrony version 3.4 +Copyright (C) 1997-2003, 2007, 2009-2018 Richard P. Curnow and others +chrony comes with ABSOLUTELY NO WARRANTY.  This is free software, and +you are welcome to redistribute it under certain conditions.  See the +GNU General Public License version 2 for details. + +chronyc> +``` + +You can enter just the subcommands at this prompt. Try using the **tracking** , **ntpdata** , and **sources** commands. The **chronyc** command line allows command recall and editing for **chronyc** subcommands. You can use the **help** subcommand to get a list of possible commands and their syntax. + +### Conclusion + +Chrony is a powerful tool for synchronizing the times of client hosts, whether they are all on the local network or scattered around the globe. It's easy to configure because, despite the large number of options available, only a few configurations are required for most circumstances. + +After my client computers have synchronized with the NTP server, I like to set the system hardware clock from the system (OS) time by using the following command: + +``` +/sbin/hwclock --systohc +``` + +This command can be added as a cron job or a script in **cron.daily** to keep the hardware clock synced with the system time. + +Chrony and NTP (the service) both use the same configuration, and the files' contents are interchangeable. The man pages for [chronyd][5], [chronyc][4], and [chrony.conf][6] contain an amazing amount of information that can help you get started or learn about esoteric configuration options. + +Do you run your own NTP server? Let us know in the comments and be sure to tell us which implementation you are using, NTP or Chrony. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/manage-ntp-chrony + +作者：[David Both][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/dboth +[b]: https://github.com/lujun9972 +[1]: https://en.wikipedia.org/wiki/Does_Anybody_Really_Know_What_Time_It_Is%3F +[2]: https://en.wikipedia.org/wiki/Network_Time_Protocol +[3]: https://chrony.tuxfamily.org/comparison.html +[4]: https://linux.die.net/man/1/chronyc +[5]: https://linux.die.net/man/8/chronyd +[6]: https://linux.die.net/man/5/chrony.conf diff --git a/sources/tech/20181004 4 Must-Have Tools for Monitoring Linux.md b/sources/tech/20181004 4 Must-Have Tools for Monitoring Linux.md index 987809aa0d..beb3bab797 100644 --- a/sources/tech/20181004 4 Must-Have Tools for Monitoring Linux.md +++ b/sources/tech/20181004 4 Must-Have Tools for Monitoring Linux.md @@ -1,5 +1,3 @@ -### translating by way-ww - 4 Must-Have Tools for Monitoring Linux ====== diff --git a/sources/tech/20181005 Dbxfs - Mount Dropbox Folder Locally As Virtual File System In Linux.md b/sources/tech/20181005 Dbxfs - Mount Dropbox Folder Locally As Virtual File System In Linux.md deleted file mode 100644 index 691600a4cc..0000000000 --- a/sources/tech/20181005 Dbxfs - Mount Dropbox Folder Locally As Virtual File System In Linux.md +++ /dev/null @@ -1,133 +0,0 @@ -Dbxfs – Mount Dropbox Folder Locally As Virtual File System In Linux -====== - -![](https://www.ostechnix.com/wp-content/uploads/2018/10/dbxfs-720x340.png) - -A while ago, we summarized all the possible ways to **[mount Google drive locally][1]** as a virtual file system and access the files stored in the google drive from your Linux operating system. Today, we are going to learn to mount Dropbox folder in your local file system using **dbxfs** utility. The dbxfs is used to mount your Dropbox folder locally as a virtual filesystem in Unix-like operating systems. While it is easy to [**install Dropbox client**][2] in Linux, this approach slightly differs from the official method. It is a command line dropbox client and requires no disk space for access. The dbxfs application is free, open source and written for Python 3.5+. - -### Installing dbxfs - -The dbxfs officially supports Linux and Mac OS. However, it should work on any POSIX system that provides a **FUSE-compatible library** or has the ability to mount **SMB** shares. Since it is written for Python 3.5, it can installed using **pip3** package manager. Refer the following guide if you haven’t installed PIP yet. - -And, install FUSE library as well. - -On Debian-based systems, run the following command to install FUSE: - -``` -$ sudo apt install libfuse2 - -``` - -On Fedora: - -``` -$ sudo dnf install fuse - -``` - -Once you installed all required dependencies, run the following command to install dbxfs utility: - -``` -$ pip3 install dbxfs - -``` - -### Mount Dropbox folder locally - -Create a mount point to mount your dropbox folder in your local file system. - -``` -$ mkdir ~/mydropbox - -``` - -Then, mount the dropbox folder locally using dbxfs utility as shown below: - -``` -$ dbxfs ~/mydropbox - -``` - -You will be asked to generate an access token: - -![](https://www.ostechnix.com/wp-content/uploads/2018/10/Generate-access-token-1.png) - -To generate an access token, just navigate to the URL given in the above output from your web browser and click **Allow** to authenticate Dropbox access. You need to log in to your dropbox account to complete authorization process. - -A new authorization code will be generated in the next screen. Copy the code and head back to your Terminal and paste it into cli-dbxfs prompt to finish the process. - -You will be then asked to save the credentials for future access. Type **Y** or **N** whether you want to save or decline. And then, you need to enter a passphrase twice for the new access token. - -Finally, click **Y** to accept **“/home/username/mydropbox”** as the default mount point. If you want to set different path, type **N** and enter the location of your choice. - -[![Generate access token 2][3]][4] - -All done! From now on, you can see your Dropbox folder is locally mounted in your filesystem. - -![](https://www.ostechnix.com/wp-content/uploads/2018/10/Dropbox-in-file-manager.png) - -### Change Access Token Storage Path - -By default, the dbxfs application will store your Dropbox access token in the system keyring or an encrypted file. However, you might want to store it in a **gpg** encrypted file or something else. If so, get an access token by creating a personal app on the [Dropbox developers app console][5]. - -![](https://www.ostechnix.com/wp-content/uploads/2018/10/access-token.png) - -Once the app is created, click **Generate** button in the next button. This access token can be used to access your Dropbox account via the API. Don’t share your access token with anyone. - -![](https://www.ostechnix.com/wp-content/uploads/2018/10/Create-a-new-app.png) - -Once you created an access token, encrypt it using any encryption tools of your choice, such as [**Cryptomater**][6], [**Cryptkeeper**][7], [**CryptGo**][8], [**Cryptr**][9], [**Tomb**][10], [**Toplip**][11] and [**GnuPG**][12] etc., and store it in your preferred location. - -Next edit the dbxfs configuration file and add the following line in it: - -``` -"access_token_command": ["gpg", "--decrypt", "/path/to/access/token/file.gpg"] - -``` - -You can find the dbxfs configuration file by running the following command: - -``` -$ dbxfs --print-default-config-file - -``` - -For more details, refer dbxfs help section: - -``` -$ dbxfs -h - -``` - -As you can see, mounting Dropfox folder locally in your file system using Dbxfs utility is no big deal. As far tested, dbxfs just works fine as expected. Give it a try if you’re interested to see how it works and let us know about your experience in the comment section below. - -And, that’s all for now. Hope this was useful. More good stuff to come. Stay tuned! - -Cheers! - - - --------------------------------------------------------------------------------- - -via: https://www.ostechnix.com/dbxfs-mount-dropbox-folder-locally-as-virtual-file-system-in-linux/ - -作者：[SK][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://www.ostechnix.com/author/sk/ -[1]: https://www.ostechnix.com/how-to-mount-google-drive-locally-as-virtual-file-system-in-linux/ -[2]: https://www.ostechnix.com/install-dropbox-in-ubuntu-18-04-lts-desktop/ -[3]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 -[4]: http://www.ostechnix.com/wp-content/uploads/2018/10/Generate-access-token-2.png -[5]: https://dropbox.com/developers/apps -[6]: https://www.ostechnix.com/cryptomator-open-source-client-side-encryption-tool-cloud/ -[7]: https://www.ostechnix.com/how-to-encrypt-your-personal-foldersdirectories-in-linux-mint-ubuntu-distros/ -[8]: https://www.ostechnix.com/cryptogo-easy-way-encrypt-password-protect-files/ -[9]: https://www.ostechnix.com/cryptr-simple-cli-utility-encrypt-decrypt-files/ -[10]: https://www.ostechnix.com/tomb-file-encryption-tool-protect-secret-files-linux/ -[11]: https://www.ostechnix.com/toplip-strong-file-encryption-decryption-cli-utility/ -[12]: https://www.ostechnix.com/an-easy-way-to-encrypt-and-decrypt-files-from-commandline-in-linux/ diff --git a/sources/tech/20181008 Taking notes with Laverna, a web-based information organizer.md b/sources/tech/20181008 Taking notes with Laverna, a web-based information organizer.md index 71adf0112b..27616a9f6e 100644 --- a/sources/tech/20181008 Taking notes with Laverna, a web-based information organizer.md +++ b/sources/tech/20181008 Taking notes with Laverna, a web-based information organizer.md @@ -1,5 +1,3 @@ -translating by cyleft - Taking notes with Laverna, a web-based information organizer ====== diff --git a/sources/tech/20181011 Exploring the Linux kernel- The secrets of Kconfig-kbuild.md b/sources/tech/20181011 Exploring the Linux kernel- The secrets of Kconfig-kbuild.md index f2885b177c..2fd085eda0 100644 --- a/sources/tech/20181011 Exploring the Linux kernel- The secrets of Kconfig-kbuild.md +++ b/sources/tech/20181011 Exploring the Linux kernel- The secrets of Kconfig-kbuild.md @@ -1,4 +1,5 @@ -translating by leemeans +Translating by Jamskr + Exploring the Linux kernel: The secrets of Kconfig/kbuild ====== Dive into understanding how the Linux config/build system works. diff --git a/sources/tech/20181022 Improve login security with challenge-response authentication.md b/sources/tech/20181022 Improve login security with challenge-response authentication.md deleted file mode 100644 index 66ed2534b0..0000000000 --- a/sources/tech/20181022 Improve login security with challenge-response authentication.md +++ /dev/null @@ -1,183 +0,0 @@ -Improve login security with challenge-response authentication -====== - -![](https://fedoramagazine.org/wp-content/uploads/2018/10/challenge-response-816x345.png) - -### Introduction - -Today, Fedora offers multiple ways to improve the secure authentication of our user accounts. Of course it has the familiar user name and password to login. It also offers additional authentication options such as biometric, fingerprint, smart card, one-time password, and even challenge-response authentication. - -Each authentication method has clear pros and cons. That, in itself, could be a topic for a rather lengthy article. Fedora Magazine has covered a few of these options previously: - - -+ [Using the YubiKey4 with Fedora][1] -+ [Fedora 28: Better smart card support in OpenSSH][2] - - -One of the most secure methods in modern Fedora releases is offline hardware challenge-response. It’s also one of the easiest to deploy. Here’s how. - -### Challenge-response authentication - -Technically, when you provide a password, you’re responding to a user name challenge. The offline challenge response covered here requires your user name first. Next, Fedora challenges you to provide an encrypted physical hardware token. The token responds to the challenge with another encrypted key it stores via the Pluggable Authentication Modules (PAM) framework. Finally, Fedora prompts you for the password. This prevents someone from just using a found hardware token, or just using a user name and password without the correct encrypted key. - -This means that in addition to your user name and password, you must have previously registered one or more encrypted hardware tokens with the OS. And you have to provide that physical hardware token to be able to authenticate with your user name. - -Some challenge-response methods, like one time passwords (OTP), take an encrypted code key on the hardware token, and pass that key across the network to a remote authentication server. The server then tells Fedora’s PAM framework if it’s is a valid token for that user name. This is great if the authentication server(s) are on the local network. The downside is if the network connection is down or you’re working remote without a network connection, you can’t use this remote authentication method. You could be locked out of the system until you can connect through the network to the server. - -Sometimes a workplace requires use of Yubikey One Time Passwords (OTP) configuration. However, on home or personal systems you may prefer a local challenge-response configuration. Everything is local, and the method requires no remote network calls. The following process works on Fedora 27, 28, and 29. - -### Preparation - -#### Hardware token keys - -First you need a secure hardware token key. Specifically, this process requires a Yubikey 4, Yubikey NEO, or a recently released Yubikey 5 series device which also supports FIDO2. You should purchase two of them to provide a backup in case one becomes lost or damaged. You can use these keys on numerous workstations. The simpler FIDO or FIDO U2F only versions don’t work for this process, but are great for online services that use FIDO. - -#### Backup, backup, and backup - -Next, make a backup of all your important data. You may want to test the configuration in a Fedora 27/28/29 cloned VM to make sure you understand the process before setting up your personal workstation. - -#### Updating and installing - -Now make sure Fedora is up to date. Then install the required Fedora Yubikey packages via these dnf commands: - -``` -$ sudo dnf upgrade -$ sudo dnf install ykclient* ykpers* pam_yubico* -$ cd -``` - -If you’re in a VM environment, such as Virtual Box, make sure the Yubikey device is inserted in a USB port, and enable USB access to the Yubikey in the VM control. - -### Configuring Yubikey - -Verify that your user account has access to the USB Yubikey: - -``` -$ ykinfo -v -version: 3.5.0 -``` - -If the YubiKey is not detected, the following error message appears: - -``` -Yubikey core error: no yubikey present -``` - -Next, initialize each of your new Yubikeys with the following ykpersonalize command. This sets up the Yubikey configuration slot 2 with a Challenge Response using the HMAC-SHA1 algorithm, even with less than 64 characters. If you have already setup your Yubikeys for challenge-response, you don’t need to run ykpersonalize again. - -``` -ykpersonalize -2 -ochal-resp -ochal-hmac -ohmac-lt64 -oserial-api-visible -``` - -Some users leave the YubiKey in their workstation while using it, and even use challenge-response for virtual machines. However, for more security you may prefer to manually trigger the Yubikey to respond to challenge. - -To add that manual challenge button trigger, add the -ochal-btn-trig flag. This flag causes the Yubikey to flash the yubikey LED on a request. It waits for you to press the button on the hardware key area within 15 seconds to produce the response key. - -``` -$ ykpersonalize -2 -ochal-resp -ochal-hmac -ohmac-lt64 -ochal-btn-trig -oserial-api-visible -``` - -Do this for each of your new hardware keys, only once per key. Once you have programmed your keys, store the Yubikey configuration to ~/.yubico with the following command: - -``` -$ ykpamcfg -2 -v -debug: util.c:222 (check_firmware_version): YubiKey Firmware version: 4.3.4 - -Sending 63 bytes HMAC challenge to slot 2 -Sending 63 bytes HMAC challenge to slot 2 -Stored initial challenge and expected response in '/home/chuckfinley/.yubico/challenge-9992567'. -``` - -If you are setting up multiple keys for backup purposes, configure all the keys the same, and store each key’s challenge-response using the ykpamcfg utility. If you run the command ykpersonalize on an existing registered key, you must store the configuration again. - -### Configuring /etc/pam.d/sudo - -Now to verify this configuration worked, **in the same terminal window** you’ll setup sudo to require the use of the Yubikey challenge-response. Insert the following line into the /etc/pam.d/sudo file: - -``` -auth required pam_yubico.so mode=challenge-response -``` - -Insert the above auth line into the file above the auth include system-auth line. Then save the file and exit the editor. In a default Fedora 29 setup, /etc/pam.d/sudo should now look like this: - -``` -#%PAM-1.0 -auth required pam_yubico.so mode=challenge-response -auth include system-auth -account include system-auth -password include system-auth -session optional pam_keyinit.so revoke -session required pam_limits.so -session include system-auth -``` - -**Keep this original terminal window open** , and test by opening another new terminal window. In the new terminal window type: - -``` -$ sudo echo testing -``` - -You should notice the LED blinking on the key. Tap the Yubikey button and you should see a prompt for your sudo password. After you enter your password, you should see “testing” echoed in the terminal screen. - -Now test to ensure a correct failure. Start another terminal window and remove the Yubikey from the USB port. Verify that sudo no longer works without the Yubikey with this command: - -``` -$ sudo echo testing fail -``` - -You should immediately be prompted for the sudo password. Even if you enter the password, it should fail. - -### Configuring Gnome Desktop Manager - -Once your testing is complete, now you can add challenge-response support for the graphical login. Re-insert your Yubikey into the USB port. Next you’ll add the following line to the /etc/pam.d/gdm-password file: - -``` -auth required pam_yubico.so mode=challenge-response -``` - -Open a terminal window, and issue the following command. You can use another editor if desired: - -``` -$ sudo vi /etc/pam.d/gdm-password -``` - -You should see the yubikey LED blinking. Press the yubikey button, then enter the password at the prompt. - -Modify the /etc/pam.d/gdm-password file to add the new auth line above the existing line auth substack password-auth. The top of the file should now look like this: - -``` -auth [success=done ignore=ignore default=bad] pam_selinux_permit.so -auth required pam_yubico.so mode=challenge-response -auth substack password-auth -auth optional pam_gnome_keyring.so -auth include postlogin - -account required pam_nologin.so -``` - -Save the changes and exit the editor. If you use vi, the key sequence is to hit the **Esc** key, then type wq! at the prompt to save and exit. - -### Conclusion - -Now log out of GNOME. With the Yubikey inserted into the USB port, click on your user name in the graphical login. The Yubikey LED begins to flash. Touch the button, and you will be prompted for your password. - -If you lose the Yubikey, you can still use the secondary backup Yubikey in addition to your set password. You can also add additional Yubikey configurations to your user account. - -If someone gains access to your password, they still can’t login without your physical hardware Yubikey. Congratulations! You’ve now dramatically increased the security of your workstation login. - --------------------------------------------------------------------------------- - -via: https://fedoramagazine.org/login-challenge-response-authentication/ - -作者：[nabooengineer][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://fedoramagazine.org/author/nabooengineer/ -[b]: https://github.com/lujun9972 -[1]: https://fedoramagazine.org/using-the-yubikey4-with-fedora/ -[2]: https://fedoramagazine.org/fedora-28-better-smart-card-support-openssh/ - diff --git a/sources/tech/20181025 How to write your favorite R functions in Python.md b/sources/tech/20181025 How to write your favorite R functions in Python.md deleted file mode 100644 index a06d3557b9..0000000000 --- a/sources/tech/20181025 How to write your favorite R functions in Python.md +++ /dev/null @@ -1,153 +0,0 @@ -How to write your favorite R functions in Python -====== -R or Python? This Python script mimics convenient R-style functions for doing statistics nice and easy. - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/search_find_code_issue_bug_programming.png?itok=XPrh7fa0) - -One of the great modern battles of data science and machine learning is "Python vs. R." There is no doubt that both have gained enormous ground in recent years to become top programming languages for data science, predictive analytics, and machine learning. In fact, according to a recent IEEE article, Python overtook C++ as the [top programming language][1] and R firmly secured its spot in the top 10. - -However, there are some fundamental differences between these two. [R was developed primarily][2] as a tool for statistical analysis and quick prototyping of a data analysis problem. Python, on the other hand, was developed as a general purpose, modern object-oriented language in the same vein as C++ or Java but with a simpler learning curve and more flexible demeanor. Consequently, R continues to be extremely popular among statisticians, quantitative biologists, physicists, and economists, whereas Python has slowly emerged as the top language for day-to-day scripting, automation, backend web development, analytics, and general machine learning frameworks and has an extensive support base and open source development community work. - -### Mimicking functional programming in a Python environment - -[R's nature as a functional programming language][3] provides users with an extremely simple and compact interface for quick calculations of probabilities and essential descriptive/inferential statistics for a data analysis problem. For example, wouldn't it be great to be able to solve the following problems with just a single, compact function call? - - * How to calculate the mean/median/mode of a data vector. - * How to calculate the cumulative probability of some event following a normal distribution. What if the distribution is Poisson? - * How to calculate the inter-quartile range of a series of data points. - * How to generate a few random numbers following a Student's t-distribution. - - - -The R programming environment can do all of these. - -On the other hand, Python's scripting ability allows analysts to use those statistics in a wide variety of analytics pipelines with limitless sophistication and creativity. - -To combine the advantages of both worlds, you just need a simple Python-based wrapper library that contains the most commonly used functions pertaining to probability distributions and descriptive statistics defined in R-style. This enables you to call those functions really fast without having to go to the proper Python statistical libraries and figure out the whole list of methods and arguments. - -### Python wrapper script for most convenient R-functions - -[I wrote a Python script][4] to define the most convenient and widely used R-functions in simple, statistical analysis—in Python. After importing this script, you will be able to use those R-functions naturally, just like in an R programming environment. - -The goal of this script is to provide simple Python subroutines mimicking R-style statistical functions for quickly calculating density/point estimates, cumulative distributions, and quantiles and generating random variates for important probability distributions. - -To maintain the spirit of R styling, the script uses no class hierarchy and only raw functions are defined in the file. Therefore, a user can import this one Python script and use all the functions whenever they're needed with a single name call. - -Note that I use the word mimic. Under no circumstance am I claiming to emulate R's true functional programming paradigm, which consists of a deep environmental setup and complex relationships between those environments and objects. This script allows me (and I hope countless other Python users) to quickly fire up a Python program or Jupyter notebook, import the script, and start doing simple descriptive statistics in no time. That's the goal, nothing more, nothing less. - -If you've coded in R (maybe in grad school) and are just starting to learn and use Python for data analysis, you will be happy to see and use some of the same well-known functions in your Jupyter notebook in a manner similar to how you use them in your R environment. - -Whatever your reason, using this script is fun. - -### Simple examples - -To start, just import the script and start working with lists of numbers as if they were data vectors in R. - -``` -from R_functions import * -lst=[20,12,16,32,27,65,44,45,22,18] - -``` - -Say you want to calculate the [Tuckey five-number][5] summary from a vector of data points. You just call one simple function, **fivenum** , and pass on the vector. It will return the five-number summary in a NumPy array. - -``` -lst=[20,12,16,32,27,65,44,45,22,18] -fivenum(lst) -> array([12. , 18.5, 24.5, 41. , 65. ]) -``` - -Maybe you want to know the answer to the following question: - -Suppose a machine outputs 10 finished goods per hour on average with a standard deviation of 2. The output pattern follows a near normal distribution. What is the probability that the machine will output at least 7 but no more than 12 units in the next hour? - -The answer is essentially this: - -![](https://opensource.com/sites/default/files/uploads/r-functions-in-python_1.png) - -You can obtain the answer with just one line of code using **pnorm** : - -``` -pnorm(12,10,2)-pnorm(7,10,2) -> 0.7745375447996848 -``` - -Or maybe you need to answer the following: - -Suppose you have a loaded coin with the probability of turning heads up 60% every time you toss it. You are playing a game of 10 tosses. How do you plot and map out the chances of all the possible number of wins (from 0 to 10) with this coin? - -You can obtain a nice bar chart with just a few lines of code using just one function, **dbinom** : - -``` -probs=[] -import matplotlib.pyplot as plt -for i in range(11): -    probs.append(dbinom(i,10,0.6)) -plt.bar(range(11),height=probs) -plt.grid(True) -plt.show() -``` - -![](https://opensource.com/sites/default/files/uploads/r-functions-in-python_2.png) - -### Simple interface for probability calculations - -R offers an extremely simple and intuitive interface for quick calculations from essential probability distributions. The interface goes like this: - - * **d** {distribution} gives the density function value at a point **x** - * **p** {distribution} gives the cumulative value at a point **x** - * **q** {distribution} gives the quantile function value at a probability **p** - * **r** {distribution} generates one or multiple random variates - - - -In our implementation, we stick to this interface and its associated argument list so you can execute these functions exactly like you would in an R environment. - -### Currently implemented functions - -The following R-style functions are implemented in the script for fast calling. - - * Mean, median, variance, standard deviation - * Tuckey five-number summary, IQR - * Covariance of a matrix or between two vectors - * Density, cumulative probability, quantile function, and random variate generation for the following distributions: normal, uniform, binomial, Poisson, F, Student's t, Chi-square, beta, and gamma. - - - -### Work in progress - -Obviously, this is a work in progress, and I plan to add some other convenient R-functions to this script. For example, in R, a single line of command **lm** can get you an ordinary least-square fitted model to a numerical dataset with all the necessary inferential statistics (P-values, standard error, etc.). This is powerfully brief and compact! On the other hand, standard linear regression problems in Python are often tackled using [Scikit-learn][6], which needs a bit more scripting for this use, so I plan to incorporate this single function linear model fitting feature using Python's [statsmodels][7] backend. - -If you like and use this script in your work, please help others find it by starring or forking its [GitHub repository][8]. Also, you can check my other [GitHub repos][9] for fun code snippets in Python, R, or MATLAB and some machine learning resources. - -If you have any questions or ideas to share, please contact me at [tirthajyoti[AT]gmail.com][10]. If you are, like me, passionate about machine learning and data science, please [add me on LinkedIn][11] or [follow me on Twitter. ][12] - -Originally published on [Towards Data Science][13]. Reposted under [CC BY-SA 4.0][14]. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/10/write-favorite-r-functions-python - -作者：[Tirthajyoti Sarkar][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://opensource.com/users/tirthajyoti -[b]: https://github.com/lujun9972 -[1]: https://spectrum.ieee.org/at-work/innovation/the-2018-top-programming-languages -[2]: https://www.coursera.org/lecture/r-programming/overview-and-history-of-r-pAbaE -[3]: http://adv-r.had.co.nz/Functional-programming.html -[4]: https://github.com/tirthajyoti/StatsUsingPython/blob/master/R_Functions.py -[5]: https://en.wikipedia.org/wiki/Five-number_summary -[6]: http://scikit-learn.org/stable/ -[7]: https://www.statsmodels.org/stable/index.html -[8]: https://github.com/tirthajyoti/StatsUsingPython -[9]: https://github.com/tirthajyoti?tab=repositories -[10]: mailto:tirthajyoti@gmail.com -[11]: https://www.linkedin.com/in/tirthajyoti-sarkar-2127aa7/ -[12]: https://twitter.com/tirthajyotiS -[13]: https://towardsdatascience.com/how-to-write-your-favorite-r-functions-in-python-11e1e9c29089 -[14]: https://creativecommons.org/licenses/by-sa/4.0/ diff --git a/sources/tech/20181105 5 Easy Tips for Linux Web Browser Security.md b/sources/tech/20181105 5 Easy Tips for Linux Web Browser Security.md deleted file mode 100644 index 17d06c72d6..0000000000 --- a/sources/tech/20181105 5 Easy Tips for Linux Web Browser Security.md +++ /dev/null @@ -1,157 +0,0 @@ -5 Easy Tips for Linux Web Browser Security -====== -![](https://www.linux.com/learn/intro-to-linux/2018/11/5-easy-tips-linux-web-browser-security) - -If you use your Linux desktop and never open a web browser, you are a special kind of user. For most of us, however, a web browser has become one of the most-used digital tools on the planet. We work, we play, we get news, we interact, we bank… the number of things we do via a web browser far exceeds what we do in local applications. Because of that, we need to be cognizant of how we work with web browsers, and do so with a nod to security. Why? Because there will always be nefarious sites and people, attempting to steal information. Considering the sensitive nature of the information we send through our web browsers, it should be obvious why security is of utmost importance. - -So, what is a user to do? In this article, I’ll offer a few basic tips, for users of all sorts, to help decrease the chances that your data will end up in the hands of the wrong people. I will be demonstrating on the Firefox web browser, but many of these tips cross the application threshold and can be applied to any flavor of web browser. - -### 1. Choose Your Browser Wisely - -Although most of these tips apply to most browsers, it is imperative that you select your web browser wisely. One of the more important aspects of browser security is the frequency of updates. New issues are discovered quite frequently and you need to have a web browser that is as up to date as possible. Of major browsers, here is how they rank with updates released in 2017: - - 1. Chrome released 8 updates (with Chromium following up with numerous security patches throughout the year). - - 2. Firefox released 7 updates. - - 3. Edge released 2 updates. - - 4. Safari released 1 update (although Apple does release 5-6 security patches yearly). - - - - -But even if your browser of choice releases an update every month, if you (as a user) don’t upgrade, that update does you no good. This can be problematic with certain Linux distributions. Although many of the more popular flavors of Linux do a good job of keeping web browsers up to date, others do not. So, it’s crucial that you manually keep on top of browser updates. This might mean your distribution of choice doesn’t include the latest version of your web browser of choice in its standard repository. If that’s the case, you can always manually download the latest version of the browser from the developer’s download page and install from there. - -If you like to live on the edge, you can always use a beta or daily build version of your browser. Do note, that using a daily build or beta version does come with it the possibility of unstable software. Say, however, you’re okay with using a daily build of Firefox on a Ubuntu-based distribution. To do that, add the necessary repository with the command: - -``` -sudo apt-add-repository ppa:ubuntu-mozilla-daily/ppa -``` - -Update apt and install the daily Firefox with the commands: - -``` -sudo apt-get update -sudo apt-get install firefox -``` - -What’s most important here is to never allow your browser to get far out of date. You want to have the most updated version possible on your desktop. Period. If you fail this one thing, you could be using a browser that is vulnerable to numerous issues. - -### 2. Use A Private Window - -Now that you have your browser updated, how do you best make use of it? If you happen to be of the really concerned type, you should consider always using a private window. Why? Private browser windows don’t retain your data: No passwords, no cookies, no cache, no history… nothing. The one caveat to browsing through a private window is that (as you probably expect), every time you go back to a web site, or use a service, you’ll have to re-type any credentials to log in. If you’re serious about browser security, never saving credentials should be your default behavior. - -This leads me to a reminder that everyone needs: Make your passwords strong! In fact, at this point in the game, everyone should be using a password manager to store very strong passwords. My password manager of choice is [Universal Password Manager][1]. - -### 3\. Protect Your Passwords - -For some, having to retype those passwords every single time might be too much. So what do you do if you want to protect those passwords, while not having to type them constantly? If you use Firefox, there’s a built-in tool, called Master Password. With this enabled, none of your browser’s saved passwords are accessible, until you correctly type the master password. To set this up, do the following: - - 1. Open Firefox. - - 2. Click the menu button. - - 3. Click Preferences. - - 4. In the Preferences window, click Privacy & Security. - - 5. In the resulting window, click the checkbox for Use a master password (Figure 1). - - 6. When prompted, type and verify your new master password (Figure 2). - - 7. Close and reopen Firefox. - - - - -![Master Password][3] - -Figure 1: The Master Password option in Firefox Preferences. - -[Used with permission][4] - -![Setting password][6] - -Figure 2: Setting the Master Password in Firefox. - -[Used with permission][4] - -### 4\. Know your Extensions - -There are plenty of privacy-focused extensions available for most browsers. What extensions you use will depend upon what you want to focus on. For myself, I choose the following extensions for Firefox: - - * [Firefox Multi-Account Containers][7] \- Allows you to configure certain sites to open in a containerized tab. - - * [Facebook Container][8] \- Always opens Facebook in a containerized tab (Firefox Multi-Account Containers is required for this). - - * [Avast Online Security][9] \- Identifies and blocks known phishing sites and displays a website’s security rating (curated by the Avast community of over 400 million users). - - * [Mining Blocker][10] \- Blocks all CPU-Crypto Miners before they are loaded. - - * [PassFF][11] \- Integrates with pass (A UNIX password manager) to store credentials safely. - - * [Privacy Badger][12] \- Automatically learns to block trackers. - - * [uBlock Origin][13] \- Blocks trackers based on known lists. - - -Of course, you’ll find plenty more security-focused extensions for: - - - -+ [Firefox][2] - -+ [Chrome, Chromium, & Vivaldi][5] - -+ [Opera][14] - - -Not every web browser offers extensions. Some, such as Midoria, offer a limited about of built-in plugins, that can be enabled/disabled (Figure 3). However, you won’t find third-party plugins available for the majority of these lightweight browsers. - -![Midori Browser][15] - -Figure 3: The Midori Browser plugins window. - -[Used with permission][4] - -### 5\. Virtualize - -For those that are concerned about releasing locally stored data to prying eyes, one option would be to only use a browser on a virtual machine. To do this, install the likes of [VirtualBox][16], install a Linux guest, and then run whatever browser you like in the virtual environment. If you then apply the above tips, you can be sure your browsing experience will be safe. - -### The Truth of the Matter - -The truth is, if the machine you are working from is on a network, you’re never going to be 100% safe. However, if you use that web browser intelligently you’ll get more bang out of your security buck and be less prone to having data stolen. The silver lining with Linux is that the chances of getting malicious software installed on your machine is exponentially less than if you were using another platform. Just remember to always use the latest release of your browser, keep your operating system updated, and use caution with the sites you visit. - -Learn more about Linux through the free ["Introduction to Linux" ][17] course from The Linux Foundation and edX. - --------------------------------------------------------------------------------- - -via: https://www.linux.com/learn/intro-to-linux/2018/11/5-easy-tips-linux-web-browser-security - -作者：[Jack Wallen][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://www.linux.com/users/jlwallen -[b]: https://github.com/lujun9972 -[1]: http://upm.sourceforge.net/ -[2]: https://addons.mozilla.org/en-US/firefox/search/?q=security -[3]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/browsersecurity_1.jpg?itok=gHMPKEvr (Master Password) -[4]: https://www.linux.com/licenses/category/used-permission -[5]: https://chrome.google.com/webstore/search/security -[6]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/browsersecurity_2.jpg?itok=4L7DR2Ik (Setting password) -[7]: https://addons.mozilla.org/en-US/firefox/addon/multi-account-containers/?src=search -[8]: https://addons.mozilla.org/en-US/firefox/addon/facebook-container/?src=search -[9]: https://addons.mozilla.org/en-US/firefox/addon/avast-online-security/?src=search -[10]: https://addons.mozilla.org/en-US/firefox/addon/miningblocker/?src=search -[11]: https://addons.mozilla.org/en-US/firefox/addon/passff/?src=search -[12]: https://addons.mozilla.org/en-US/firefox/addon/privacy-badger17/ -[13]: https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/?src=search -[14]: https://addons.opera.com/en/search/?query=security -[15]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/browsersecurity_3.jpg?itok=hdNor0gw (Midori Browser) -[16]: https://www.virtualbox.org/ -[17]: https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20181105 5 Minimal Web Browsers for Linux.md b/sources/tech/20181105 5 Minimal Web Browsers for Linux.md new file mode 100644 index 0000000000..1fbc18aeae --- /dev/null +++ b/sources/tech/20181105 5 Minimal Web Browsers for Linux.md @@ -0,0 +1,163 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (5 Minimal Web Browsers for Linux) +[#]: via: (https://www.linux.com/blog/intro-to-linux/2018/11/5-minimal-web-browsers-linux) +[#]: author: (Jack Wallen https://www.linux.com/users/jlwallen) +[#]: url: ( ) + +5 Minimal Web Browsers for Linux +====== +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/minimal.jpg?itok=ifA0Y3pV) + +There are so many reasons to enjoy the Linux desktop. One reason I often state up front is the almost unlimited number of choices to be found at almost every conceivable level. From how you interact with the operating system (via a desktop interface), to how daemons run, to what tools you use, you have a multitude of options. + +The same thing goes for web browsers. You can use anything from open source favorites, such as [Firefox][1] and [Chromium][2], or closed sourced industry darlings like [Vivaldi][3] and [Chrome][4]. Those options are full-fledged browsers with every possible bell and whistle you’ll ever need. For some, these feature-rich browsers are perfect for everyday needs. + +There are those, however, who prefer using a web browser without all the frills. In fact, there are many reasons why you might prefer a minimal browser over a standard browser. For some, it’s about browser security, while others look at a web browser as a single-function tool (as opposed to a one-stop shop application). Still others might be running low-powered machines that cannot handle the requirements of, say, Firefox or Chrome. Regardless of the reason, Linux has you covered. + +Let’s take a look at five of the minimal browsers that can be installed on Linux. I’ll be demonstrating these browsers on the Elementary OS platform, but each of these browsers are available to nearly every distribution in the known Linuxverse. Let’s dive in. + +### GNOME Web + +GNOME Web (codename Epiphany, which means [“a usually sudden manifestation or perception of the essential nature or meaning of something”][5]) is the default web browser for Elementary OS, but it can be installed from the standard repositories. (Note, however, that the recommended installation of Epiphany is via Flatpak or Snap). If you choose to install via the standard package manager, issue a command such as sudo apt-get install epiphany-browser -y for successful installation. + +Epiphany uses the WebKit rendering engine, which is the same engine used in Apple’s Safari browser. Couple that rendering engine with the fact that Epiphany has very little in terms of bloat to get in the way, you will enjoy very fast page-rendering speeds. Epiphany development follows strict adherence to the following guidelines: + + * Simplicity - Feature bloat and user interface clutter are considered evil. + + * Standards compliance - No non-standard features will ever be introduced to the codebase. + + * Software freedom - Epiphany will always be released under a license that respects freedom. + + * Human interface - Epiphany follows the [GNOME Human Interface Guidelines][6]. + + * Minimal preferences - Preferences are only added when they make sense and after careful consideration. + + * Target audience - Non-technical users are the primary target audience (which helps to define the types of features that are included). + + + + +GNOME Web is as clean and simple a web browser as you’ll find (Figure 1). + +![GNOME Web][8] + +Figure 1: The GNOME Web browser displaying a minimal amount of preferences for the user. + +[Used with permission][9] + +The GNOME Web manifesto reads: + +A web browser is more than an application: it is a way of thinking, a way of seeing the world. Epiphany's principles are simplicity, standards compliance, and software freedom. + +### Netsurf + +The [Netsurf][10] minimal web browser opens almost faster than you can release the mouse button. Netsurf uses its own layout and rendering engine (designed completely from scratch), which is rather hit and miss in its rendering (Figure 2). + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/minimalbrowsers_2.jpg?itok=KhGhIKlj) + +Although you might find Netsurf to suffer from rendering issues on certain sites, understand the Hubbub HTML parser is following the work-in-progress HTML5 specification, so there will be issues popup now and then. To ease those rendering headaches, Netsurf does include HTTPS support, web page thumbnailing, URL completion, scale view, bookmarks, full-screen mode, keyboard shorts, and no particular GUI toolkit requirements. That last bit is important, especially when you switch from one desktop to another. + +For those curious as to the requirements for Netsurf, the browser can run on a machine as slow as a 30Mhz ARM 6 computer with 16MB of RAM. That’s impressive, by today’s standard. + +### QupZilla + +If you’re looking for a minimal browser that uses the Qt Framework and the QtWebKit rendering engine, [QupZilla][11] might be exactly what you’re looking for. QupZilla does include all the standard features and functions you’d expect from a web browser, such as bookmarks, history, sidebar, tabs, RSS feeds, ad blocking, flash blocking, and CA Certificates management. Even with those features, QupZilla still manages to remain a very fast lightweight web browser. Other features include: Fast startup, speed dial homepage, built-in screenshot tool, browser themes, and more. +One feature that should appeal to average users is that QupZilla has a more standard preferences tools than found in many lightweight browsers (Figure 3). So, if going too far outside the lines isn’t your style, but you still want something lighter weight, QupZilla is the browser for you. + +![QupZilla][13] + +Figure 3: The QupZilla preferences tool. + +[Used with permission][9] + +### Otter Browser + +Otter Browser is a free, open source attempt to recreate the closed-source offerings found in the Opera Browser. Otter Browser uses the WebKit rendering engine and has an interface that should be immediately familiar with any user. Although lightweight, Otter Browser does include full-blown features such as: + + * Passwords manager + + * Add-on manager + + * Content blocking + + * Spell checking + + * Customizable GUI + + * URL completion + + * Speed dial (Figure 4) + + * Bookmarks and various related features + + * Mouse gestures + + * User style sheets + + * Built-in Note tool + + +![Otter][15] + +Figure 4: The Otter Browser Speed Dial tab. + +[Used with permission][9] + +Otter Browser can be run on nearly any Linux distribution from an [AppImage][16], so there’s no installation required. Just download the AppImage file, give the file executable permissions (with the command chmod u+x otter-browser-*.AppImage), and then launch the app with the command ./otter-browser*.AppImage. + +Otter Browser does an outstanding job of rendering websites and could function as your go-to minimal browser with ease. + +### Lynx + +Let’s get really minimal. When I first started using Linux, back in ‘97, one of the web browsers I often turned to was a text-only take on the app called [Lynx][17]. It should come as no surprise that Lynx is still around and available for installation from the standard repositories. As you might expect, Lynx works from the terminal window and doesn’t display pretty pictures or render much in the way of advanced features (Figure 5). In fact, Lynx is as bare-bones a browser as you will find available. Because of how bare-bones this web browser is, it’s not recommended for everyone. But if you happen to have a gui-less web server and you have a need to be able to read the occasional website, Lynx can be a real lifesaver. + +![Lynx][19] + +Figure 5: The Lynx browser rendering the Linux.com page. + +[Used with permission][9] + +I have also found Lynx an invaluable tool when troubleshooting certain aspects of a website (or if some feature on a website is preventing me from viewing the content in a regular browser). Another good reason to use Lynx is when you only want to view the content (and not the extraneous elements). + +### Plenty More Where This Came From + +There are plenty more minimal browsers than this. But the list presented here should get you started down the path of minimalism. One (or more) of these browsers are sure to fill that need, whether you’re running it on a low-powered machine or not. + +Learn more about Linux through the free ["Introduction to Linux" ][20]course from The Linux Foundation and edX. + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/intro-to-linux/2018/11/5-minimal-web-browsers-linux + +作者：[Jack Wallen][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.linux.com/users/jlwallen +[b]: https://github.com/lujun9972 +[1]: https://www.mozilla.org/en-US/firefox/new/ +[2]: https://www.chromium.org/ +[3]: https://vivaldi.com/ +[4]: https://www.google.com/chrome/ +[5]: https://www.merriam-webster.com/dictionary/epiphany +[6]: https://developer.gnome.org/hig/stable/ +[7]: /files/images/minimalbrowsers1jpg +[8]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/minimalbrowsers_1.jpg?itok=Q7wZLF8B (GNOME Web) +[9]: /licenses/category/used-permission +[10]: https://www.netsurf-browser.org/ +[11]: https://qupzilla.com/ +[12]: /files/images/minimalbrowsers3jpg +[13]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/minimalbrowsers_3.jpg?itok=O8iMALWO (QupZilla) +[14]: /files/images/minimalbrowsers4jpg +[15]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/minimalbrowsers_4.jpg?itok=5bCa0z-e (Otter) +[16]: https://sourceforge.net/projects/otter-browser/files/ +[17]: https://lynx.browser.org/ +[18]: /files/images/minimalbrowsers5jpg +[19]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/minimalbrowsers_5.jpg?itok=p_Lmiuxh (Lynx) +[20]: https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20181106 How To Check The List Of Packages Installed From Particular Repository.md b/sources/tech/20181106 How To Check The List Of Packages Installed From Particular Repository.md new file mode 100644 index 0000000000..81111b465c --- /dev/null +++ b/sources/tech/20181106 How To Check The List Of Packages Installed From Particular Repository.md @@ -0,0 +1,342 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (How To Check The List Of Packages Installed From Particular Repository?) +[#]: via: (https://www.2daygeek.com/how-to-check-the-list-of-packages-installed-from-particular-repository/) +[#]: author: (Prakash Subramanian https://www.2daygeek.com/author/prakash/) +[#]: url: ( ) + +How To Check The List Of Packages Installed From Particular Repository? +====== + +If you would like to check the list of package installed from particular repository then you are in the right place to get it done. + +Why we need this detail? It may helps you to isolate the installed packages list based on the repository. + +Like, it’s coming from distribution official repository or these are coming from PPA or these are coming from other resources, etc., + +You may want to know what are the packages came from third party repositories to keep eye on those to avoid any damages on your system. + +So many third party repositories and PPAs are available for Linux. These repositories are included set of packages which is not available in distribution repository due to some limitation. + +It helps administrator to easily install some of the important packages which is not available in the distribution official repository. Installing third party repository on production system is not advisable as this may not properly maintained by the repository maintainer due to many reasons. + +So, you have to decide whether you want to install or not. I can say, we can believe some of the third party repositories which is well maintained and suggested by Linux distributions like [EPEL repository][1], Copr (Cool Other Package Repo), etc,. + +If you would like to see the list of package was installed from the corresponding repo, use the following commands based on your distributions. + +[List of Major repositories][2] and it’s details are below. + + * **`CentOS:`** [EPEL][1], [ELRepo][3], etc is [CentOS Community Approved Repositories][4]. + * **`Fedora:`** [RPMfusion repo][5] is commonly used by most of the [Fedora][6] users. + * **`ArchLinux:`** ArchLinux community repository contains packages that have been adopted by Trusted Users from the Arch User Repository. + * **`openSUSE:`** [Packman repo][7] offers various additional packages for openSUSE, especially but not limited to multimedia related applications and libraries that are on the openSUSE Build Service application blacklist. It’s the largest external repository of openSUSE packages. + * **`Ubuntu:`** Personal Package Archives (PPAs) are a kind of repository. Developers create them in order to distribute their software. You can find this information on the PPA’s Launchpad page. Also, you can enable Cananical partners repositories. + + + +### What Is Repository? + +A software repository is a central place which stores the software packages for the particular application. + +All the Linux distributions are maintaining their own repositories and they allow users to retrieve and install packages on their machine. + +Each vendor offered a unique package management tool to manage their repositories such as search, install, update, upgrade, remove, etc. + +Most of the Linux distributions comes as freeware except RHEL and SUSE. To access their repositories you need to buy a subscriptions. + +### How To Check The List Of Packages Installed From Particular Repository on RHEL/CentOS Systems? + +This can be done in multiple ways. Here we will be giving you all the possible options and you can choose which one is best for you. + +### Method-1: Using Yum Command + +RHEL & CentOS systems are using RPM packages hence we can use the [Yum Package Manager][8] to get this information. + +YUM stands for Yellowdog Updater, Modified is an open-source command-line front-end package-management utility for RPM based systems such as Red Hat Enterprise Linux (RHEL) and CentOS. + +Yum is the primary tool for getting, installing, deleting, querying, and managing RPM packages from distribution repositories, as well as other third-party repositories. + +``` +[[email protected] ~]# yum list installed | grep @epel +apachetop.x86_64 0.15.6-1.el7 @epel +aria2.x86_64 1.18.10-2.el7.1 @epel +atop.x86_64 2.3.0-8.el7 @epel +axel.x86_64 2.4-9.el7 @epel +epel-release.noarch 7-11 @epel +lighttpd.x86_64 1.4.50-1.el7 @epel +``` + +Alternatively, you can use the yum command with other option to get the same details like above. + +``` +# yum repo-pkgs epel list installed +Loaded plugins: fastestmirror +Loading mirror speeds from cached hostfile + * epel: epel.mirror.constant.com +Installed Packages +apachetop.x86_64 0.15.6-1.el7 @epel +aria2.x86_64 1.18.10-2.el7.1 @epel +atop.x86_64 2.3.0-8.el7 @epel +axel.x86_64 2.4-9.el7 @epel +epel-release.noarch 7-11 @epel +lighttpd.x86_64 1.4.50-1.el7 @epel +``` + +### Method-2: Using Yumdb Command + +Yumdb info provides information similar to yum info but additionally it provides package checksum data, type, user info (who installed the package). Since yum 3.2.26 yum has started storing additional information outside of the rpmdatabase (where user indicates it was installed by the user, and dep means it was brought in as a dependency). + +``` +# yumdb search from_repo epel* |egrep -v '(from_repo|^$)' +Loaded plugins: fastestmirror +apachetop-0.15.6-1.el7.x86_64 +aria2-1.18.10-2.el7.1.x86_64 +atop-2.3.0-8.el7.x86_64 +axel-2.4-9.el7.x86_64 +epel-release-7-11.noarch +lighttpd-1.4.50-1.el7.x86_64 +``` + +### Method-3: Using Repoquery Command + +repoquery is a program for querying information from YUM repositories similarly to rpm queries. + +``` +# repoquery -a --installed --qf "%{ui_from_repo} %{name}" | grep '^@epel' +@epel apachetop +@epel aria2 +@epel atop +@epel axel +@epel epel-release +@epel lighttpd +``` + +### How To Check The List Of Packages Installed From Particular Repository on Fedora System? + +DNF stands for Dandified yum. We can tell DNF, the next generation of yum package manager (Fork of Yum) using hawkey/libsolv library for back-end. Aleš Kozumplík started working on DNF since Fedora 18 and its implemented/launched in Fedora 22 finally. + +[Dnf command][9] is used to install, update, search & remove packages on Fedora 22 and later system. It automatically resolve dependencies and make it smooth package installation without any trouble. + +``` +# dnf list installed | grep @updates +NetworkManager.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-adsl.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-bluetooth.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-libnm.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-libreswan.x86_64 1.2.10-1.fc29 @updates +NetworkManager-libreswan-gnome.x86_64 1.2.10-1.fc29 @updates +NetworkManager-openvpn.x86_64 1:1.8.8-1.fc29 @updates +NetworkManager-openvpn-gnome.x86_64 1:1.8.8-1.fc29 @updates +NetworkManager-ovs.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-ppp.x86_64 1:1.12.4-2.fc29 @updates +. +. +``` + +Alternatively, you can use the dnf command with other option to get the same details like above. + +``` +# dnf repo-pkgs updates list installed +Installed Packages +NetworkManager.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-adsl.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-bluetooth.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-libnm.x86_64 1:1.12.4-2.fc29 @updates +NetworkManager-libreswan.x86_64 1.2.10-1.fc29 @updates +NetworkManager-libreswan-gnome.x86_64 1.2.10-1.fc29 @updates +NetworkManager-openvpn.x86_64 1:1.8.8-1.fc29 @updates +NetworkManager-openvpn-gnome.x86_64 1:1.8.8-1.fc29 @updates +NetworkManager-ovs.x86_64 1:1.12.4-2.fc29 @updates +. +. +``` + +### How To Check The List Of Packages Installed From Particular Repository on openSUSE System? + +Zypper is a command line package manager which makes use of libzypp. [Zypper command][10] provides functions like repository access, dependency solving, package installation, etc. + +``` +zypper search -ir "Update Repository (Non-Oss)" +Loading repository data... +Reading installed packages... + +S | Name | Summary | Type +---+----------------------------+---------------------------------------------------+-------- +i | gstreamer-0_10-fluendo-mp3 | GStreamer plug-in from Fluendo for MP3 support | package +i+ | openSUSE-2016-615 | Test-update for openSUSE Leap 42.2 Non Free | patch +i+ | openSUSE-2017-724 | Security update for unrar | patch +i | unrar | A program to extract, test, and view RAR archives | package +``` + +Alternatively, we can use repo id instead of repo name. + +``` +zypper search -ir 2 +Loading repository data... +Reading installed packages... + +S | Name | Summary | Type +---+----------------------------+---------------------------------------------------+-------- +i | gstreamer-0_10-fluendo-mp3 | GStreamer plug-in from Fluendo for MP3 support | package +i+ | openSUSE-2016-615 | Test-update for openSUSE Leap 42.2 Non Free | patch +i+ | openSUSE-2017-724 | Security update for unrar | patch +i | unrar | A program to extract, test, and view RAR archives | package +``` + +### How To Check The List Of Packages Installed From Particular Repository on ArchLinux System? + +[Pacman command][11] stands for package manager utility. pacman is a simple command-line utility to install, build, remove and manage Arch Linux packages. Pacman uses libalpm (Arch Linux Package Management (ALPM) library) as a back-end to perform all the actions. + +``` +$ paclist community +acpi 1.7-2 +acpid 2.0.30-1 +adapta-maia-theme 3.94.0.149-1 +android-tools 9.0.0_r3-1 +blueman 2.0.6-1 +brotli 1.0.7-1 +. +. +ufw 0.35-5 +unace 2.5-10 +usb_modeswitch 2.5.2-1 +viewnior 1.7-1 +wallpapers-2018 1.0-1 +xcursor-breeze 5.11.5-1 +xcursor-simpleandsoft 0.2-8 +xcursor-vanilla-dmz-aa 0.4.5-1 +xfce4-whiskermenu-plugin-gtk3 2.3.0-1 +zeromq 4.2.5-1 +``` + +### How To Check The List Of Packages Installed From Particular Repository on Debian Based Systems? + +For Debian based systems, it can be done using grep command. + +If you want to know the list of installed repositories on your system, use the following command. + +``` +$ ls -lh /var/lib/apt/lists/ | uniq +total 370M +-rw-r--r-- 1 root root 10K Oct 26 10:53 archive.canonical.com_ubuntu_dists_bionic_InRelease +-rw-r--r-- 1 root root 6.4K Oct 26 10:53 archive.canonical.com_ubuntu_dists_bionic_partner_binary-amd64_Packages +-rw-r--r-- 1 root root 6.4K Oct 26 10:53 archive.canonical.com_ubuntu_dists_bionic_partner_binary-i386_Packages +-rw-r--r-- 1 root root 3.2K Jun 12 21:19 archive.canonical.com_ubuntu_dists_bionic_partner_i18n_Translation-en +drwxr-xr-x 2 _apt root 4.0K Jul 25 08:44 auxfiles +-rw-r--r-- 1 root root 3.7K Oct 16 15:13 download.virtualbox.org_virtualbox_debian_dists_bionic_contrib_binary-amd64_Packages +-rw-r--r-- 1 root root 7.2K Oct 16 15:13 download.virtualbox.org_virtualbox_debian_dists_bionic_contrib_Contents-amd64.lz4 +-rw-r--r-- 1 root root 4.4K Oct 16 15:13 download.virtualbox.org_virtualbox_debian_dists_bionic_InRelease +-rw-r--r-- 1 root root 34 Mar 19 2018 download.virtualbox.org_virtualbox_debian_dists_bionic_non-free_Contents-amd64.lz4 +-rw-r--r-- 1 root root 6.4K Sep 21 09:42 in.archive.ubuntu.com_ubuntu_dists_bionic-backports_Contents-amd64.lz4 +-rw-r--r-- 1 root root 6.4K Sep 21 09:42 in.archive.ubuntu.com_ubuntu_dists_bionic-backports_Contents-i386.lz4 +-rw-r--r-- 1 root root 73K Nov 6 11:16 in.archive.ubuntu.com_ubuntu_dists_bionic-backports_InRelease +. +. +-rw-r--r-- 1 root root 29 May 11 06:39 security.ubuntu.com_ubuntu_dists_bionic-security_main_dep11_icons-64x64.tar.gz +-rw-r--r-- 1 root root 747K Nov 5 23:57 security.ubuntu.com_ubuntu_dists_bionic-security_main_i18n_Translation-en +-rw-r--r-- 1 root root 2.8K Oct 9 22:37 security.ubuntu.com_ubuntu_dists_bionic-security_multiverse_binary-amd64_Packages +-rw-r--r-- 1 root root 3.7K Oct 9 22:37 security.ubuntu.com_ubuntu_dists_bionic-security_multiverse_binary-i386_Packages +-rw-r--r-- 1 root root 1.8K Jul 24 23:06 security.ubuntu.com_ubuntu_dists_bionic-security_multiverse_i18n_Translation-en +-rw-r--r-- 1 root root 519K Nov 5 20:12 security.ubuntu.com_ubuntu_dists_bionic-security_universe_binary-amd64_Packages +-rw-r--r-- 1 root root 517K Nov 5 20:12 security.ubuntu.com_ubuntu_dists_bionic-security_universe_binary-i386_Packages +-rw-r--r-- 1 root root 11K Nov 6 05:36 security.ubuntu.com_ubuntu_dists_bionic-security_universe_dep11_Components-amd64.yml.gz +-rw-r--r-- 1 root root 8.9K Nov 6 05:36 security.ubuntu.com_ubuntu_dists_bionic-security_universe_dep11_icons-48x48.tar.gz +-rw-r--r-- 1 root root 16K Nov 6 05:36 security.ubuntu.com_ubuntu_dists_bionic-security_universe_dep11_icons-64x64.tar.gz +-rw-r--r-- 1 root root 315K Nov 5 20:12 security.ubuntu.com_ubuntu_dists_bionic-security_universe_i18n_Translation-en +``` + +To get the list of installed packages from the `security.ubuntu.com` repository. + +``` +$ grep Package /var/lib/apt/lists/security.ubuntu.com_*_Packages | awk '{print $2;}' +amd64-microcode +apache2 +apache2-bin +apache2-data +apache2-dbg +apache2-dev +. +. +znc +znc-dev +znc-perl +znc-python +znc-tcl +zsh-static +zziplib-bin +``` + +The security repository containing multiple branches (main, multiverse and universe) and if you would like to list out the installed packages from the particular repository `universe` then use the following format. + +``` +$ grep Package /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_bionic-security_universe*_Packages | awk '{print $2;}' +ant +ant-doc +ant-optional +apache2-suexec-custom +apache2-suexec-pristine +apparmor-easyprof +apport-kde +apport-noui +apport-valgrind +apt-transport-https +. +. +xul-ext-gdata-provider +xul-ext-lightning +xvfb +znc +znc-dev +znc-perl +znc-python +znc-tcl +zsh-static +zziplib-bin +``` + +one more example for `ppa.launchpad.net` repository. + +``` +$ grep Package /var/lib/apt/lists/ppa.launchpad.net_*_Packages | awk '{print $2;}' +notepadqq +notepadqq-gtk +notepadqq-common +notepadqq +notepadqq-gtk +notepadqq-common +numix-gtk-theme +numix-icon-theme +numix-icon-theme-circle +numix-icon-theme-square +numix-gtk-theme +numix-icon-theme +numix-icon-theme-circle +numix-icon-theme-square +``` + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/how-to-check-the-list-of-packages-installed-from-particular-repository/ + +作者：[Prakash Subramanian][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/prakash/ +[b]: https://github.com/lujun9972 +[1]: https://www.2daygeek.com/install-enable-epel-repository-on-rhel-centos-scientific-linux-oracle-linux/ +[2]: https://www.2daygeek.com/category/repository/ +[3]: https://www.2daygeek.com/install-enable-elrepo-on-rhel-centos-scientific-linux/ +[4]: https://www.2daygeek.com/additional-yum-repositories-for-centos-rhel-fedora-systems/ +[5]: https://www.2daygeek.com/install-enable-rpm-fusion-repository-on-centos-fedora-rhel/ +[6]: https://fedoraproject.org/wiki/Third_party_repositories +[7]: https://www.2daygeek.com/install-enable-packman-repository-on-opensuse-leap/ +[8]: https://www.2daygeek.com/yum-command-examples-manage-packages-rhel-centos-systems/ +[9]: https://www.2daygeek.com/dnf-command-examples-manage-packages-fedora-system/ +[10]: https://www.2daygeek.com/zypper-command-examples-manage-packages-opensuse-system/ +[11]: https://www.2daygeek.com/pacman-command-examples-manage-packages-arch-linux-system/ diff --git a/sources/tech/20181107 Top 30 OpenStack Interview Questions and Answers.md b/sources/tech/20181107 Top 30 OpenStack Interview Questions and Answers.md deleted file mode 100644 index e00fc5452b..0000000000 --- a/sources/tech/20181107 Top 30 OpenStack Interview Questions and Answers.md +++ /dev/null @@ -1,324 +0,0 @@ -Top 30 OpenStack Interview Questions and Answers -====== -Now a days most of the firms are trying to migrate their IT infrastructure and Telco Infra into private cloud i.e OpenStack. If you planning to give interviews on Openstack admin profile, then below list of interview questions might help you to crack the interview. - -![](https://www.linuxtechi.com/wp-content/uploads/2018/11/OpenStack-Interview-Questions.jpg) - -### Q:1 Define OpenStack and its key components? - -Ans: It is a bundle of opensource software, which all in combine forms a provide cloud software known as OpenStack.OpenStack is known as Stack of Open source Software or Projects. - -Following are the key components of OpenStack - - * **Nova** – It handles the Virtual machines at compute level and performs other computing task at compute or hypervisor level. - * **Neutron** – It provides the networking functionality to VMs, Compute and Controller Nodes. - * **Keystone** – It provides the identity service for all cloud users and openstack services. In other words, we can say Keystone a method to provide access to cloud users and services. - * **Horizon** – It provides a GUI (Graphical User Interface), using the GUI Admin can all day to day operations task at ease. - * **Cinder** – It provides the block storage functionality, generally in OpenStack Cinder is integrated with Chef and ScaleIO to service block storage to Compute & Controller nodes. - * **Swift** – It provides the object storage functionality. Generally, Glance images are on object storage. External storage like ScaleIO can work as Object storage too and can easily be integrated with Glance Service. - * **Glance** – It provides Cloud image services, using glance admin used to upload and download cloud images. - * **Heat** – It provides an orchestration service or functionality. Using Heat admin can easily VMs as stack and based on requirements VMs in the stack can be scale-in and Scale-out - * **Ceilometer** – It provides the telemetry and billing services. - - - -### Q:2 What are services generally run on a controller node? - -Ans: Following services run on a controller node: - - * Identity Service ( KeyStone) - * Image Service ( Glance) - * Nova Services like Nova API, Nova Scheduler & Nova DB - * Block & Object Service - * Ceilometer Service - * MariaDB / MySQL and RabbitMQ Service - * Management services of Networking (Neutron) and Networking agents - * Orchestration Service (Heat) - - - -### Q:3 What are the services generally run on a Compute Node? - -Ans: Following services run on a compute node, - - * Nova-Compute - * Networking Services like OVS - - - -### Q:4 What is the default location of VMs on the Compute Nodes? - -Ans: VMs in the Compute node are stored at “ **/var/lib/nova/instances** ” - -### Q:5 What is default location of glance images? - -Ans: As the Glance service runs on a controller node, all the glance images are store under the folder “ **/var/lib/glance/images** ” on a controller node. - -Read More : [**How to Create and Delete Virtual Machine(VM) from Command line in OpenStack**][1] - -### Q:6 Tell me the command how to spin a VM from Command Line? - -Ans: We can easily spin a new VM using the following openstack command, - -``` -# openstack server create --flavor {flavor-name} --image {Image-Name-Or-Image-ID}  --nic net-id={Network-ID} --security-group {Security_Group_ID} –key-name {Keypair-Name} -``` - -### Q:7 How to list the network namespace of a tenant in OpenStack? - -Ans: Network namespace of a tenant can be listed using “ip net ns” command - -``` -~# ip netns list -qdhcp-a51635b1-d023-419a-93b5-39de47755d2d -haproxy -vrouter -``` - -### Q:8 How to execute command inside network namespace in openstack? - -Ans: Let’s assume we want to execute “ifconfig” command inside the network namespace “qdhcp-a51635b1-d023-419a-93b5-39de47755d2d”, then run the beneath command, - -Syntax : ip netns exec {network-space} - -``` -~# ip netns exec qdhcp-a51635b1-d023-419a-93b5-39de47755d2d "ifconfig" -``` - -### Q:9 How to upload and download a cloud image in Glance from command line? - -Ans: A Cloud image can be uploaded in glance from command using beneath openstack command, - -``` -~# openstack image create --disk-format qcow2 --container-format bare   --public --file {Name-Cloud-Image}.qcow2     -``` - -Use below openstack command to download a cloud image from command line, - -``` -~# glance image-download --file --progress  -``` - -### Q:10 How to reset error state of a VM into active in OpenStack env? - -Ans: There are some scenarios where some VMs went to error state and this error state can be changed into active state using below commands, - -``` -~# nova reset-state --active {Instance_id} -``` - -### Q:11 How to get list of available Floating IPs from command line? - -Ans: Available floating ips can be listed using the below command, - -``` -~]# openstack ip floating list | grep None | head -10 -``` - -### Q:12 How to provision a virtual machine in specific availability zone and compute Host? - -Ans: Let’s assume we want to provision a VM on the availability zone NonProduction in compute-02, use the beneath command to accomplish this, - -``` -~]# openstack server create --flavor m1.tiny --image cirros --nic net-id=e0be93b8-728b-4d4d-a272-7d672b2560a6 --security-group NonProd_SG  --key-name linuxtec --availability-zone NonProduction:compute-02  nonprod_testvm -``` - -### Q:13 How to get list of VMs which are provisioned on a specific Compute node? - -Ans: Let’s assume we want to list the vms which are provisioned on compute-0-19, use below - -Syntax: openstack server list –all-projects –long -c Name -c Host | grep -i {Compute-Node-Name} - -``` -~# openstack server list --all-projects --long -c Name -c Host | grep -i  compute-0-19 -``` - -### Q:14 How to view the console log of an openstack instance from command line? - -Ans: Console logs of an instance can be viewed from the command line using the following commands, - -First get the ID of an instance and then use the below command, - -``` -~# openstack console log show {Instance-id} -``` - -### Q:15 How to get console URL of an openstack instance? - -Ans: Console URL of an instance can be retrieved from command line using the below openstack command, - -``` -~# openstack console url show {Instance-id} -``` - -### Q:16 How to create a bootable cinder / block storage volume from command line? - -Ans: To Create a bootable cinder or block storage volume (assume 8 GB) , refer the below steps: - - * Get Image list using below - - - -``` -~# openstack image list | grep -i cirros -| 89254d46-a54b-4bc8-8e4d-658287c7ee92 | cirros  | active | -``` - - * Create bootable volume of size 8 GB using cirros image - - - -``` -~# cinder create --image-id 89254d46-a54b-4bc8-8e4d-658287c7ee92 --display-name cirros-bootable-vol  8 -``` - -### Q:17 How to list all projects or tenants that has been created in your opentstack? - -Ans: Projects or tenants list can be retrieved from the command using the below openstack command, - -``` -~# openstack project list --long -``` - -### Q:18 How to list the endpoints of openstack services? - -Ans: Openstack service endpoints are classified into three categories, - - * Public Endpoint - * Internal Endpoint - * Admin Endpoint - - - -Use below openstack command to view endpoints of each openstack service, - -``` -~# openstack catalog list -``` - -To list the endpoint of a specific service like keystone use below, - -``` -~# openstack catalog show keystone -``` - -Read More : [**Step by Step Instance Creation Flow in OpenStack**][2] - -### Q:19 In which order we should restart nova services on a controller node? - -Ans: Following order should be followed to restart the nova services on openstack controller node, - - * service nova-api restart - * service nova-cert restart - * service nova-conductor restart - * service nova-consoleauth restart - * service nova-scheduler restart - - - -### Q:20 Let’s assume DPDK ports are configured on compute node for data traffic, now how you will check the status of dpdk ports? - -Ans: As DPDK ports are configured via openvSwitch (OVS), use below commands to check the status, - -### Q:21 How to add new rules to the existing SG(Security Group) from command line in openstack? - -Ans: New rules to the existing SG in openstack can be added using the neutron command, - -``` -~# neutron security-group-rule-create --protocol   --port-range-min --port-range-max --direction  --remote-ip-prefix Security-Group-Name -``` - -### Q:22 How to view the OVS bridges configured on Controller and Compute Nodes? - -Ans: OVS bridges on Controller and Compute nodes can be viewed using below command, - -``` -~]# ovs-vsctl show -``` - -### Q:23 What is the role of Integration Bridge(br-int) on the Compute Node ? - -Ans: The integration bridge (br-int) performs VLAN tagging and untagging for the traffic coming from and to the instance running on the compute node. - -Packets leaving the n/w interface of an instance goes through the linux bridge (qbr) using the virtual interface qvo. The interface qvb is connected to the Linux Bridge & interface qvo is connected to integration bridge (br-int). The qvo port on integration bridge has an internal VLAN tag that gets appended to packet header when a packet reaches to the integration bridge. - -### Q:24 What is the role of Tunnel Bridge (br-tun) on the compute node? - -Ans: The tunnel bridge (br-tun) translates the VLAN tagged traffic from integration bridge to the tunnel ids using OpenFlow rules. - -br-tun (tunnel bridge) allows the communication between the instances on different networks. Tunneling helps to encapsulate the traffic travelling over insecure networks, br-tun supports two overlay networks i.e GRE and VXLAN - -### Q:25 What is the role of external OVS bridge (br-ex)? - -Ans: As the name suggests, this bridge forwards the traffic coming to and from the network to allow external access to instances. br-ex connects to the physical interface like eth2, so that floating IP traffic for tenants networks is received from the physical network and routed to the tenant network ports. - -### Q:26 What is function of OpenFlow rules in OpenStack Networking? - -Ans: OpenFlow rules is a mechanism that define how a packet will reach to destination starting from its source. OpenFlow rules resides in flow tables. The flow tables are part of OpenFlow switch. - -When a packet arrives to a switch, it is processed by the first flow table, if it doesn’t match any flow entries in the table then packet is dropped or forwarded to another table. - -### Q:27 How to display the information about a OpenFlow switch (like ports, no. of tables, no of buffer)? - -Ans: Let’s assume we want to display the information about OpenFlow switch (br-int), run the following command, - -``` -root@compute-0-15# ovs-ofctl show br-int -OFPT_FEATURES_REPLY (xid=0x2): dpid:0000fe981785c443 -n_tables:254, n_buffers:256 -capabilities: FLOW_STATS TABLE_STATS PORT_STATS QUEUE_STATS ARP_MATCH_IP -actions: output enqueue set_vlan_vid set_vlan_pcp strip_vlan mod_dl_src mod_dl_dst mod_nw_src mod_nw_dst mod_nw_tos mod_tp_src mod_tp_dst - 1(patch-tun): addr:3a:c6:4f:bd:3e:3b -     config:     0 -     state:      0 -     speed: 0 Mbps now, 0 Mbps max - 2(qvob35d2d65-f3): addr:b2:83:c4:0b:42:3a -     config:     0 -     state:      0 -     current:    10GB-FD COPPER -     speed: 10000 Mbps now, 0 Mbps max - ……………………………………… -``` - -### Q:28 How to display the entries for all the flows in a switch? - -Ans: Flows entries of a switch can be displayed using the command ‘ **ovs-ofctl dump-flows** ‘ - -Let’s assume we want to display flow entries of OVS integration bridge (br-int), - -### Q:29 What are Neutron Agents and how to list all neutron agents? - -Ans: OpenStack neutron server acts as the centralized controller, the actual network configurations are executed either on compute and network nodes. Neutron agents are software entities that carry out configuration changes on compute or network nodes. Neutron agents communicate with the main neutron service via Neuron API and message queue. - -Neutron agents can be listed using the following command, - -``` -~# openstack network agent list -c ‘Agent type’ -c Host -c Alive -c State -``` - -### Q:30 What is CPU pinning? - -Ans: CPU pinning refers to reserving the physical cores for specific virtual machine. It is also known as CPU isolation or processor affinity. The configuration is in two parts: - - * it ensures that virtual machine can only run on dedicated cores - * it also ensures that common host processes don’t run on those cores - - - -In other words we can say pinning is one to one mapping of a physical core to a guest vCPU. - --------------------------------------------------------------------------------- - -via: https://www.linuxtechi.com/openstack-interview-questions-answers/ - -作者：[Pradeep Kumar][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: http://www.linuxtechi.com/author/pradeep/ -[b]: https://github.com/lujun9972 -[1]: https://www.linuxtechi.com/create-delete-virtual-machine-command-line-openstack/ -[2]: https://www.linuxtechi.com/step-by-step-instance-creation-flow-in-openstack/ diff --git a/sources/tech/20181108 My Google-free Android life.md b/sources/tech/20181108 My Google-free Android life.md new file mode 100644 index 0000000000..4e94af0de8 --- /dev/null +++ b/sources/tech/20181108 My Google-free Android life.md @@ -0,0 +1,191 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (My Google-free Android life) +[#]: via: (https://lushka.al/my-android-setup/) +[#]: author: (Anxhelo Lushka https://lushka.al/) + +My Google-free Android life +====== + +People have been asking me a lot lately about my phone, my Android setup and how I manage to use my smartphone without Google Services. Well, this is a post that aims to address precisely that. I would like to make this article really beginner-friendly so I’ll try to go slow, going through things one by one and including screenshots so you can have a better view on how things happen and work like. + +At first I’ll start with why Google Services are (imo) bad for your device. I could cut it short and guide you to this [post][1] by [Richard Stallman][2], but I’m grabbing a few main points from it and adding them here. + + * Nonfree software required + * In general, most Google services require running nonfree Javascript code. Nowadays, nothing whatsoever appears if Javascript is disabled, even making a Google account requires running nonfree software (Javascript sent by the site), same thing for logging in. + * Surveillance + * Google quietly combines its ad-tracking profiles with its browsing profiles and stores a huge amount of data on each user. + * Terms of Service + * Google cuts off accounts for users that resell Pixel phones. They lose access to all of their mail and documents stored in Google servers under that account. + * Censorship + * Amazon and Google have cut off domain-fronting, a feature used to enable people in tyrannical countries to reach communication systems that are banned there. + * Google has agreed to perform special censorship of Youtube for the government of Pakistan, deleting views that the state opposes. This will help the illiberal Pakistani state suppress dissent. + * Youtube’s “content ID” automatically deletes posted videos in a way copyright law does not require. + + + +These are just a few reasons, but you can read the post by RMS I linked above in which he tries to explain these points in detail. Although it may look like a tinfoil hat reaction to you, all these actions already happen everyday in real life. + +### Next on the list, my setup and a tutorial on how I achieved it + +I own a **[Xiaomi Redmi Note 5 Pro][3]** smartphone (codename **whyred** ), produced in China by [Xiaomi][4], which I bought for around 185 EUR 4 months ago (from the time of writing this post). + +Now you might be thinking, ‘but why did you buy a Chinese brand, they are not reliable’. Yes, it is not made from the usuals as you would expect, such as Samsung (which people often associate with Android, which is plain wrong), OnePlus, Nokia etc, but you should know almost every phone is produced in China. + +There were a few reasons I chose this phone, first one of course being the price. It is a quite **budget-friendly** device, so most people are able to afford it. Next one would be the specs, which on paper (not only) are pretty decents for the price tag. With a 6 inch screen (Full HD resolution), a **4000 mAh battery** (superb battery life), 4GB of RAM, 64GB of storage, dual back cameras (12MP + 5MP), a front camera with flash (13MP) and a decent efficient Snapdragon 636, it was probably the best choice at that moment. + +The issue with it was that it came with [MIUI][5], the Android skin that Xiaomi ships with most of its devices (except the Android One project devices). Yes, it is not that horrible, it has some extra features, but the problems lie deeper within. One of the reasons these devices from Xiaomi are so cheap (afaik they only have 5-10% win margin from sales) is that **they include data mining and ads in the system altogether with MIUI**. In this way, the system apps requires extra unnecessary permissions that mine your data and bombard you with ads, from which Xiaomi earns money. + +Funnily enough, the Weather app included wanted access to my contacts and to make calls, why would it need that if it would just show the weather? Another case was with the Recorder app, it also required contacts and internet permissions, probably to send those recordings back to Xiaomi. + +To fix this, I’d have to format the phone and get rid of MIUI. This has become increasingly difficult with the latest phones in the market. + +The concept of formatting a phone is simple, you remove the existing system and install a new one of your preference (Android-only in this case). To do that, you have to have your [bootloader][6] unlocked. + +> A bootloader is a computer program that loads an operating system (OS) or runtime environment for the computer after completion of the self-tests. — [Wikipedia][7] + +The problem here is that Xiaomi has a specific policy about the bootloader unlocking. A few months ago, the process was like this. You would have to [make a request][8] to Xiaomi to obtain an unlock code for your phone, by giving a valid reason, but this would not always work, as they could just refuse your request without reason and explanation. + +Now, that process has changed. You’ll have to download a specific software from Xiaomi, called [Mi Unlock][9], install it in your Windows PC, [activate Debugging Settings in Developer Options][10] on your phone, reboot to the bootloader mode (by holding the Volume Down + Power button while the phone is off) and connect the phone to your computer to start a process called “Approval”. This process starts a timer on the Xiaomi servers that will allow you to **unlock the phone only after a period of 15 days** (or a month in some rare cases, totally random) goes by. + +![Mi Unlock app][11] + +After this period of 15 days has passed, you have to re-connect your phone and do the same procedure as above, then by pressing the Unlock button your bootloader will be unlocked and this will allow you to install other ROM-s (systems). **Careful, make sure to backup your data because unlocking the bootloader deletes everything in the phone**. + +The next step would be finding a system ([ROM][12]) that works for your device. I searched through the [XDA Developers Forum][13], which is a place where Android developers and users exchange ideas, apps etc. Fortunately, my phone is quite popular so it had [its own forum category][14]. There, I skimmed through some popular ROM-s for my device and decided to use the [AOSiP ROM][15] (AOSiP standing for Android Open Source illusion Project). + +**EDIT** : Someone emailed me to say that my article is exactly what [/e/][16] does and is targeted to. I wanted to say thank you for reaching out but that is not true at all. The reasoning behind my opinion about /e/ can also be found in this [website][17], but I’ll list a few of the reasons here. + +eelo is a “foundation” that got over 200K € in funding from Kickstarter and IndieGoGo, promising to create a mobile OS and web services that are open and secure and protect your privacy. + + 1. Their OS is based on LineageOS 14.1 (Android 7.1) with microG and other open source apps with it, which already exists for a long time now and it’s called [Lineage for microG][18]. + 2. Instead of building all apps from the source code, they download the APKs from [APKPure][19] and put them in the ROM, without knowing if those APKs contain proprietary code/malware in them. + 3. At one point, they were literally just removing the Lineage copyright header from their code and adding theirs. + 4. They love to delete negative feedback and censor their users’ opinions in their Telegram group chat. + + + +In conclusion, I **don’t recommend using /e/** ROM-s (at least until now). + +Another thing you would likely want to do is have [root access][20] to your phone, to make it truly yours and modify files in the system, such as use a system-wide adblocker etc. To do this, I decided to use [Magisk][21], a godsend app developed by a student to help you gain root access on your device and install what are called [modules][22], basically software. + +After downloading the ROM and Magisk, I had to install them on my phone. To do that, I moved the files to my SD card on the phone. Now, to install the system, I had to use something called a [recovery system][23]. The one I use is called [TWRP][24] (standing for TeamWin Recovery Project), a popular solution. + +To install the recovery system (sounds hard, I know), I had to [flash][20] the file on the phone. To do that, I connected my phone with the computer (Fedora Linux system) and with something called [ADB Tools][25] I issued a command that overwrites the system recovery with the custom one I had. + +> fastboot flash recovery twrp.img + +After this was done, I turned off the phone and kept Volume Up + Power button pressed until I saw the TWRP screen show up. That meant I was good to go and it was ready to receive my commands. + +![TWRP screen][26] + +Next step was to **issue a Wipe command** , necessary when you first install a custom ROM on your phone. As you can see from the image above, the Wipe command clears the Data, Cache and Dalvik (there is also an advanced option that allows us to tick a box to delete the System one too, as we don’t need the old one anymore). + +This takes a few moments and after that, your phone is basically clean. Now it’s time to **install the system**. By pressing the Install button on the main screen, we select the zip file we added there before (the ROM file) and swipe the screen to install it. Next, we have to install Magisk, which gives us root access to the device. + +**EDIT** : As some more experienced/power Android users might have noticed until now, there is no [GApps][27] (Google Apps) included. This is what we call GApps-less in the Android world, not having those packages installed at all. + +Note that one of the downsides of not having Google Services installed is that some of your apps might not work, for example their notifications might take longer to arrive or might not even work at all (this is what happens with Mattermost app for me). This happens because these apps use [Google Cloud Messaging][28] (now called [Firebase][29]) to wake the phone and push notifications to your phone. + +You can solve this (partially) by installing and using [microG][30] which provides some features of Google Services but allows for more control on your side. I don’t recommend using this because it still helps Google Services and you don’t really give up on them, but it’s a good start if you want to quit Google slowly and not go cold turkey on it. + +After successfully installing both, now we reboot the phone and **tada** 🎉, we are in the main screen. + +### Next part, installing the apps and configuring everything + +This is where things start to get easier. To install the apps, I use [F-Droid][31], an alternative app store that includes **only free and open source apps**. If you need apps that are not available there, you can use [Aurora Store][32], a client to download apps from the Play Store without using your Google account or getting tracked. + +F-Droid has what are called repos, a “storehouse” that contains apps you can install. I use the default ones and have added another one from [IzzyOnDroid][33], that contains some more apps not available from the default F-Droid repo and is updated more often. + +![My repos][34] + +Below you will find a list of the apps I have installed, what they replace and their use. + +This is pretty much **my list of the most useful F-Droid apps** I use, but unfortunately these are NOT the only apps I use. The proprietary apps I use (I know, I might sound a hypocrite, but not everything is replaceable, not yet at least) are as below: + + * AliExpress + * Boost for Reddit + * Google Camera (coupled with Camera API 2, this app allows me to take wonderful pictures with a 185 EUR phone, it’s just too impressive) + * Instagram + * MediaBox HD (allows me to stream movies) + * Mi Fit (an app that pairs with my Mi Band 2) + * MyVodafoneAL (the carrier app) + * ProtonMail (email app) + * Shazam Encore (to find those songs you usually listen in coffee shops) + * Snapseed (photo editing app, really simple, powerful and quite good) + * Spotify (music streaming) + * Titanium Backup (to backup my app data, wifi passwords, calls log etc.) + * ViPER4Android FX (music equalizer) + * VSCO (photo editing, never use it really) + * WhatsApp (E2E proprietary messaging app, almost everyone I know has it) + * WiFi Map (mapped hotspots that are available, handy when abroad) + + + +This is pretty much it, all the apps I use on my phone. **The configs are then pretty simple and straightforward and I can give a few tips**. + + 1. Read and check the permissions of apps carefully, don’t click ‘Install’ mindlessly. + 2. Try to use as many open source apps as possible, they both respect your privacy and are free (as in both free beer and freedom). + 3. Use a VPN as much as you can, find a reputable one and don’t use free ones, otherwise you get to be the product and you’ll get your data harvested. + 4. Don’t keep your WiFi/mobile data/location on all the time, it might be a security risk. + 5. Try not to rely on fingerprint unlock only, or better yet use only PIN/password/pattern unlock, as biometric data can be cloned and used against you, for example to unlock your phone and steal your data. + + + +And as a bonus for reading far down here, **a screenshot of my home screen** right now. + +![Screenshot][35] + + +-------------------------------------------------------------------------------- + +via: https://lushka.al/my-android-setup/ + +作者：[Anxhelo Lushka][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://lushka.al/ +[b]: https://github.com/lujun9972 +[1]: https://stallman.org/google.html +[2]: https://en.wikipedia.org/wiki/Richard_Stallman +[3]: https://www.gsmarena.com/xiaomi_redmi_note_5_pro-8893.php +[4]: https://en.wikipedia.org/wiki/Xiaomi +[5]: https://en.wikipedia.org/wiki/MIUI +[6]: https://forum.xda-developers.com/wiki/Bootloader +[7]: https://en.wikipedia.org/wiki/Booting +[8]: https://en.miui.com/unlock/ +[9]: http://www.miui.com/unlock/apply.php +[10]: https://www.youtube.com/watch?v=7zhEsJlivFA +[11]: https://lushka.al//assets/img/posts/mi-unlock.png +[12]: https://www.xda-developers.com/what-is-custom-rom-android/ +[13]: https://forum.xda-developers.com/ +[14]: https://forum.xda-developers.com/redmi-note-5-pro +[15]: https://forum.xda-developers.com/redmi-note-5-pro/development/rom-aosip-8-1-t3804473 +[16]: https://e.foundation +[17]: https://ewwlo.xyz/evil +[18]: https://lineage.microg.org/ +[19]: https://apkpure.com/ +[20]: https://lifehacker.com/5789397/the-always-up-to-date-guide-to-rooting-any-android-phone +[21]: https://forum.xda-developers.com/apps/magisk/official-magisk-v7-universal-systemless-t3473445 +[22]: https://forum.xda-developers.com/apps/magisk +[23]: http://www.smartmobilephonesolutions.com/content/android-system-recovery +[24]: https://dl.twrp.me/whyred/ +[25]: https://developer.android.com/studio/command-line/adb +[26]: https://lushka.al//assets/img/posts/android-twrp.png +[27]: https://opengapps.org/ +[28]: https://developers.google.com/cloud-messaging/ +[29]: https://firebase.google.com/docs/cloud-messaging/ +[30]: https://microg.org/ +[31]: https://f-droid.org/ +[32]: https://f-droid.org/en/packages/com.dragons.aurora/ +[33]: https://android.izzysoft.de/repo +[34]: https://lushka.al//assets/img/posts/android-fdroid-repos.jpg +[35]: https://lushka.al//assets/img/posts/android-screenshot.jpg +[36]: https://creativecommons.org/licenses/by-nc-sa/4.0/ diff --git a/sources/tech/20181112 A Free, Secure And Cross-platform Password Manager.md b/sources/tech/20181112 A Free, Secure And Cross-platform Password Manager.md deleted file mode 100644 index 66d34769c4..0000000000 --- a/sources/tech/20181112 A Free, Secure And Cross-platform Password Manager.md +++ /dev/null @@ -1,137 +0,0 @@ -A Free, Secure And Cross-platform Password Manager -====== - -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-Password-Manager-720x340.png) - -In this modern Internet era, you will surely have multiple accounts on lot of websites. It could be a personal or official mail account, social or professional network account, GitHub account, and ecommerce account etc. So you should have several different passwords for different accounts. I am sure that you are already aware that setting up same password to multiple accounts is crazy and dangerous practice. If an attacker managed to breach one of your accounts, it’s highly likely he/she will try to access other accounts you have with the same password. So, it is **highly recommended to set different passwords** to different accounts. - -However, remembering several passwords might be difficult. You can write them in a paper. But it is not an efficient method either and you might lose them over a period of time. This is where the password managers comes in help. The password managers are like a repository where you can store all your passwords for different accounts and lock them down with a master password. By this way, all you need to remember is just the master password. We already have reviewed an open source password manager named [**KeeWeb**][1]. Today, we are going to see yet another password manager called **Buttercup**. - -### About Buttercup - -Buttercup is a free, open source, secure and cross-platform password manager written using **NodeJS**. It helps you to store all your login credentials of different accounts in an encrypted archive, which can be stored in your local system or any remote services like DropBox, ownCloud, NextCloud and WebDAV-based services. It uses strong **256bit AES encryption** method to save your sensitive data with a master password. So, no one can access your login details except those who have the master password. Buttercup currently supports Linux, Mac OS and Windows. It is also available a browser extension and mobile app. so, you can access the same archive you use on the desktop application and browser extension in your Android or iOS devices as well. - -### Installing Buttercup Password Manager - -Buttercup is currently available as **.deb** , **.rpm** packages, portable AppImage and tar archives for Linux platform. Head over to the [**releases pages**][2] and download and install the version you want to use. - -Buttercup desktop application is also available in [**AUR**][3], so you can install on Arch-based systems using AUR helper programs, such as [**Yay**][4], as shown below: - -``` -$ yay -S buttercup-desktop -``` - -If you have downloaded the portable AppImage file, make it executable using command: - -``` -$ chmod +x buttercup-desktop-1.11.0-x86_64.AppImage -``` - -Then, launch it using command: - -``` -$ ./buttercup-desktop-1.11.0-x86_64.AppImage -``` - -Once you run this command, it will prompt whether you like to integrate Buttercup AppImage with your system. If you choose ‘Yes’, this will add it to your applications menu and install icons. If you don’t do this, you can still launch the application by double-clicking on the AppImage or using the above command from the Terminal. - -### Add archives - -When you launch it for the first time, you will see the following welcome screen: -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-1.png) - -We haven’t added any archives yet, so let us add one. To do so, click on the “New Archive File” button and type the name of the archive file and choose the location to save it. -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-2.png) - -You can name it as you wish. I named it mine as “mypass”. The archives will have extension **.bcup** at the end and saved in the location of your choice. - -If you already have created one, simply choose it by clicking on “Open Archive File”. - -Next, buttercup will prompt you to enter a master password to the newly created archive. It is recommended to provide a strong password to protect the archives from the unauthorized access. - -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-3.png) - -We have now created an archive and secured it with a master password. Similarly, you can create any number of archives and protect them with a password. - -Let us go ahead and add the account details in the archives. - -### Adding entries (login credentials) in the archives - -Once you created or opened the archive, you will see the following screen. - -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-4.png) - -It is like a vault where we are going to save our login credentials of different online accounts. As you can see, we haven’t added any entries yet. Let us add some. - -To add a new entry, click “ADD ENTRY” button on the lower right corner and enter your account information you want to save. - -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-5-1.png) - -If you want to add any extra detail, there is an “ADD NEW FIELD” option right under the each entry. Just click on it and add as many as fields you want to include in the entries. - -Once you added all entries, you will see them on the right pane of the Buttercup interface. - -![][6] - -### Creating new groups - -You can also group login details under different name for easy recognition. Say for example, you can group all your mail accounts under a distinct name named “my_mails”. By default, your login details will be saved under “General” group. To create a new group, click “NEW GROUP” button and provide the name for the group. When creating new entries inside a new group, just click on the group name and start adding the entries as shown above. - -### Manage and access login details - -The data stored in the archives can be edited, moved to different groups, or entirely deleted at anytime. For instance, if you want to copy the username or password to clipboard, right click on the entry and choose “Copy to Clipboard” option. - -![][7] - -To edit/modify the data in the future, just click “Edit” button under the selected entry. - -### Save archives on remote location - -By default, Buttercup will save your data on the local system. However, you can save them on different remote services, such as Dropbox, ownCloud/NextCloud, WebDAV-based service. - -To connect to these services, go to **File - > Connect Cloud Sources**. - -![](https://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-8.png) - -And, choose the service you want to connect and authorize it to save your data. - -![][8] - -You can also connect those services from the Buttercup welcome screen while adding the archives. - -### Import/Export - -Buttercup allows you to import or export data to or from other password managers, such as 1Password, Lastpass and KeePass. You can also export your data and access them from another system or device, for example on your Android phone. You can export Buttercup vaults to CSV format as well. - -![][9] - -Buttercup is a simple, yet mature and fully functional password manager. It is being actively developed for years. If you ever in need of a password manager, Buttercup might a good choice. For more details, refer the project website and github page. - -And, that’s all for now. Hope this was useful. More good stuffs to come. Stay tuned! - -Cheers! - - - --------------------------------------------------------------------------------- - -via: https://www.ostechnix.com/buttercup-a-free-secure-and-cross-platform-password-manager/ - -作者：[SK][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://www.ostechnix.com/author/sk/ -[b]: https://github.com/lujun9972 -[1]: https://www.ostechnix.com/keeweb-an-open-source-cross-platform-password-manager/ -[2]: https://github.com/buttercup/buttercup-desktop/releases/latest -[3]: https://aur.archlinux.org/packages/buttercup-desktop/ -[4]: https://www.ostechnix.com/yay-found-yet-another-reliable-aur-helper/ -[5]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 -[6]: http://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-6.png -[7]: http://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-7.png -[8]: http://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-9.png -[9]: http://www.ostechnix.com/wp-content/uploads/2018/11/buttercup-10.png diff --git a/sources/tech/20181113 An introduction to Udev- The Linux subsystem for managing device events.md b/sources/tech/20181113 An introduction to Udev- The Linux subsystem for managing device events.md deleted file mode 100644 index c406c491b0..0000000000 --- a/sources/tech/20181113 An introduction to Udev- The Linux subsystem for managing device events.md +++ /dev/null @@ -1,228 +0,0 @@ -An introduction to Udev: The Linux subsystem for managing device events -====== -Create a script that triggers your computer to do a specific action when a specific device is plugged in. -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/osdc_520x292_opensourceprescription.png?itok=gFrc_GTH) - -Udev is the Linux subsystem that supplies your computer with device events. In plain English, that means it's the code that detects when you have things plugged into your computer, like a network card, external hard drives (including USB thumb drives), mouses, keyboards, joysticks and gamepads, DVD-ROM drives, and so on. That makes it a potentially useful utility, and it's well-enough exposed that a standard user can manually script it to do things like performing certain tasks when a certain hard drive is plugged in. - -This article teaches you how to create a [udev][1] script triggered by some udev event, such as plugging in a specific thumb drive. Once you understand the process for working with udev, you can use it to do all manner of things, like loading a specific driver when a gamepad is attached, or performing an automatic backup when you attach your backup drive. - -### A basic script - -The best way to work with udev is in small chunks. Don't write the entire script upfront, but instead start with something that simply confirms that udev triggers some custom event. - -Depending on your goal for your script, you can't guarantee you will ever see the results of a script with your own eyes, so make sure your script logs that it was successfully triggered. The usual place for log files is in the **/var** directory, but that's mostly the root user's domain. For testing, use **/tmp** , which is accessible by normal users and usually gets cleaned out with a reboot. - -Open your favorite text editor and enter this simple script: - -``` -#!/usr/bin/bash - -echo $date > /tmp/udev.log -``` - -Place this in **/usr/local/bin** or some such place in the default executable path. Call it **trigger.sh** and, of course, make it executable with **chmod +x**. - -``` -$ sudo mv trigger.sh /usr/local/bin -$ sudo chmod +x /usr/local/bin/trigger.sh -``` - -This script has nothing to do with udev. When it executes, the script places a timestamp in the file **/tmp/udev.log**. Test the script yourself: - -``` -$ /usr/local/bin/trigger.sh -$ cat /tmp/udev.log -Tue Oct 31 01:05:28 NZDT 2035 -``` - -The next step is to make udev trigger the script. - -### Unique device identification - -In order for your script to be triggered by a device event, udev must know under what conditions it should call the script. In real life, you can identify a thumb drive by its color, the manufacturer, and the fact that you just plugged it into your computer. Your computer, however, needs a different set of criteria. - -Udev identifies devices by serial numbers, manufacturers, and even vendor ID and product ID numbers. Since this is early in your udev script's lifespan, be as broad, non-specific, and all-inclusive as possible. In other words, you want first to catch nearly any valid udev event to trigger your script. - -With the **udevadm monitor** command, you can tap into udev in real time and see what it sees when you plug in different devices. Become root and try it. - -``` -$ su -# udevadm monitor -``` - -The monitor function prints received events for: - - * UDEV: the event udev sends out after rule processing - * KERNEL: the kernel uevent - - - -With **udevadm monitor** running, plug in a thumb drive and watch as all kinds of information is spewed out onto your screen. Notice that the type of event is an **ADD** event. That's a good way to identify what type of event you want. - -The **udevadm monitor** command provides a lot of good info, but you can see it with prettier formatting with the command **udevadm info** , assuming you know where your thumb drive is currently located in your **/dev** tree. If not, unplug and plug your thumb drive back in, then immediately issue this command: - -``` -$ su -c 'dmesg | tail | fgrep -i sd*' -``` - -If that command returned **sdb: sdb1** , for instance, you know the kernel has assigned your thumb drive the **sdb** label. - -Alternately, you can use the **lsblk** command to see all drives attached to your system, including their sizes and partitions. - -Now that you have established where your drive is located in your filesystem, you can view udev information about that device with this command: - -``` -# udevadm info -a -n /dev/sdb | less -``` - -This returns a lot of information. Focus on the first block of info for now. - -Your job is to pick out parts of udev's report about a device that are most unique to that device, then tell udev to trigger your script when those unique attributes are detected. - -The **udevadm info** process reports on a device (specified by the device path), then "walks" up the chain of parent devices. For every device found, it prints all possible attributes using a key-value format. You can compose a rule to match according to the attributes of a device plus attributes from one single parent device. - -``` -looking at device '/devices/000:000/blah/blah//block/sdb': -  KERNEL=="sdb" -  SUBSYSTEM=="block" -  DRIVER=="" -  ATTR{ro}=="0" -  ATTR{size}=="125722368" -  ATTR{stat}==" 2765 1537 5393" -  ATTR{range}=="16" -  ATTR{discard\_alignment}=="0" -  ATTR{removable}=="1" -  ATTR{blah}=="blah" -``` - -A udev rule must contain one attribute from one single parent device. - -Parent attributes are things that describe a device from the most basic level, such as it's something that has been plugged into a physical port or it is something with a size or this is a removable device. - -Since the KERNEL label of **sdb** can change depending upon how many other drives were plugged in before you plugged that thumb drive in, that's not the optimal parent attribute for a udev rule. However, it works for a proof of concept, so you could use it. An even better candidate is the SUBSYSTEM attribute, which identifies that this is a "block" system device (which is why the **lsblk** command lists the device). - -Open a file called **80-local.rules** in **/etc/udev/rules.d** and enter this code: - -``` -SUBSYSTEM=="block", ACTION=="add", RUN+="/usr/local/bin/trigger.sh" -``` - -Save the file, unplug your test thumb drive, and reboot. - -Wait, reboot on a Linux machine? - -Theoretically, you can just issue **udevadm control --reload** , which should load all rules, but at this stage in the game, it's best to eliminate all variables. Udev is complex enough, and you don't want to be lying in bed all night wondering if that rule didn't work because of a syntax error or if you just should have rebooted. So reboot regardless of what your POSIX pride tells you. - -When your system is back online, switch to a text console (with Ctl+Alt+F3 or similar) and plug in your thumb drive. If you are running a recent kernel, you will probably see a bunch of output in your console when you plug in the drive. If you see an error message such as Could not execute /usr/local/bin/trigger.sh, you probably forgot to make the script executable. Otherwise, hopefully all you see is a device was plugged in, it got some kind of kernel device assignment, and so on. - -Now, the moment of truth: - -``` -$ cat /tmp/udev.log -Tue Oct 31 01:35:28 NZDT 2035 -``` - -If you see a very recent date and time returned from **/tmp/udev.log** , udev has successfully triggered your script. - -### Refining the rule into something useful - -The problem with this rule is that it's very generic. Plugging in a mouse, a thumb drive, or someone else's thumb drive will indiscriminately trigger your script. Now is the time to start focusing on the exact thumb drive you want to trigger your script. - -One way to do this is with the vendor ID and product ID. To get these numbers, you can use the **lsusb** command. - -``` -$ lsusb -Bus 001 Device 002: ID 8087:0024 Slacker Corp. Hub -Bus 002 Device 002: ID 8087:0024 Slacker Corp. Hub -Bus 003 Device 005: ID 03f0:3307 TyCoon Corp. -Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 hub -Bus 001 Device 003: ID 13d3:5165 SBo Networks -``` - -In this example, the **03f0:3307** before **TyCoon Corp.** denotes the idVendor and idProduct attributes. You can also see these numbers in the output of **udevadm info -a -n /dev/sdb | grep vendor** , but I find the output of **lsusb** a little easier on the eyes. - -You can now include these attributes in your rule. - -``` -SUBSYSTEM=="block", ATTRS{idVendor}=="03f0", ACTION=="add", RUN+="/usr/local/bin/thumb.sh" -``` - -Test this (yes, you should still reboot, just to make sure you're getting fresh reactions from udev), and it should work the same as before, only now if you plug in, say, a thumb drive manufactured by a different company (therefore with a different idVendor) or a mouse or a printer, the script won't be triggered. - -Keep adding new attributes to further focus in on that one unique thumb drive you want to trigger your script. Using **udevadm info -a -n /dev/sdb** , you can find out things like the vendor name, sometimes a serial number, or the product name, and so on. - -For your own sanity, be sure to add only one new attribute at a time. Most mistakes I have made (and have seen other people online make) is to throw a bunch of attributes into their udev rule and wonder why the thing no longer works. Testing attributes one by one is the safest way to ensure udev can identify your device successfully. - -### Security - -This brings up the security concerns of writing udev rules to automatically do something when a drive is plugged in. On my machines, I don't even have auto-mount turned on, and yet this article proposes scripts and rules that execute commands just by having something plugged in. - -Two things to bear in mind here. - - 1. Focus your udev rules once you have them working so they trigger scripts only when you really want them to. Executing a script that blindly copies data to or from your computer is a bad idea in case anyone who happens to be carrying the same brand of thumb drive plugs it into your box. - 2. Do not write your udev rule and scripts and forget about them. I know which computers have my udev rules on them, and those boxes are most often my personal computers, not the ones I take around to conferences or have in my office at work. The more "social" a computer is, the less likely it is to get a udev rule on it that could potentially result in my data ending up on someone else's device or someone else's data or malware on my device. - - - -In other words, as with so much of the power provided by a GNU system, it is your job to be mindful of how you are wielding that power. If you abuse it or fail to treat it with respect, it very well could go horribly wrong. - -### Udev in the real world - -Now that you can confirm that your script is triggered by udev, you can turn your attention to the function of the script. Right now, it is useless, doing nothing more than logging the fact that it has been executed. - -I use udev to trigger [automated backups][2] of my thumb drives. The idea is that the master copies of my active documents are on my thumb drive (since it goes everywhere I go and could be worked on at any moment), and those master documents get backed up to my computer each time I plug the drive into that machine. In other words, my computer is the backup drive and my production data is mobile. The source code is available, so feel free to look at the code of attachup for further examples of constraining your udev tests. - -Since that's what I use udev for the most, it's the example I'll use here, but udev can grab lots of other things, like gamepads (this is useful on systems that aren't set to load the xboxdrv module when a gamepad is attached) and cameras and microphones (useful to set inputs when a specific mic is attached), so realize that it's good for a lot more than this one example. - -A simple version of my backup system is a two-command process: - -``` -SUBSYSTEM=="block", ATTRS{idVendor}=="03f0", ACTION=="add", SYMLINK+="safety%n" -SUBSYSTEM=="block", ATTRS{idVendor}=="03f0", ACTION=="add", RUN+="/usr/local/bin/trigger.sh" -``` - -The first line detects my thumb drive with the attributes already discussed, then assigns the thumb drive a symlink within the device tree. The symlink it assigns is **safety%n**. The **%n** is a udev macro that resolves to whatever number the kernel gives to the device, such as sdb1, sdb2, sdb3, and so on. So **%n** would be the 1 or the 2 or the 3. - -This creates a symlink in the dev tree, so it does not interfere with the normal process of plugging in a device. This means that if you use a desktop environment that likes to auto-mount devices, you won't be causing problems for it. - -The second line runs the script. - -My backup script looks like this: - -``` -#!/usr/bin/bash - -mount /dev/safety1 /mnt/hd -sleep 2 -rsync -az /mnt/hd/ /home/seth/backups/ && umount /dev/safety1 -``` - -The script uses the symlink, which avoids the possibility of udev naming the drive something unexpected (for instance, if I have a thumb drive called DISK plugged into my computer already, and I plug in my other thumb drive also called DISK, the second one will be labeled DISK_, which would foil my script). It mounts **safety1** (the first partition of the drive) at my preferred mount point of **/mnt/hd**. - -Once safely mounted, it uses [rsync][3] to back up the drive to my backup folder (my actual script uses rdiff-backup, and yours can use whatever automated backup solution you prefer). - -### Udev is your dev - -Udev is a very flexible system and enables you to define rules and functions in ways that few other systems dare provide users. Learn it and use it, and enjoy the power of POSIX. - -This article builds on content from the [Slackermedia Handbook][4], which is licensed under the [GNU Free Documentation License 1.3][5]. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/11/udev - -作者：[Seth Kenlon][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://opensource.com/users/seth -[b]: https://github.com/lujun9972 -[1]: https://linux.die.net/man/8/udev -[2]: https://gitlab.com/slackermedia/attachup -[3]: https://opensource.com/article/17/1/rsync-backup-linux -[4]: http://slackermedia.info/handbook/doku.php?id=backup -[5]: http://www.gnu.org/licenses/fdl-1.3.html diff --git a/sources/tech/20181115 3 best practices for continuous integration and deployment.md b/sources/tech/20181115 3 best practices for continuous integration and deployment.md deleted file mode 100644 index 09e10f187b..0000000000 --- a/sources/tech/20181115 3 best practices for continuous integration and deployment.md +++ /dev/null @@ -1,138 +0,0 @@ -[Translating by ChiZelin] -3 best practices for continuous integration and deployment -====== -Learn about automating, using a Git repository, and parameterizing Jenkins pipelines. -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/innovation_lightbulb_gears_devops_ansible.png?itok=TSbmp3_M) - -The article covers three key topics: automating CI/CD configuration, using a Git repository for common CI/CD artifacts, and parameterizing Jenkins pipelines. - -### Terminology - -First things first; let's define a few terms. **CI/CD** is a practice that allows teams to quickly and automatically test, package, and deploy their applications. It is often achieved by leveraging a server called **[Jenkins][1]** , which serves as the CI/CD orchestrator. Jenkins listens to specific inputs (often a Git hook following a code check-in) and, when triggered, kicks off a pipeline. - -A **pipeline** consists of code written by development and/or operations teams that instructs Jenkins which actions to take during the CI/CD process. This pipeline is often something like "build my code, then test my code, and if those tests pass, deploy my application to the next highest environment (usually a development, test, or production environment)." Organizations often have more complex pipelines, incorporating tools such as artifact repositories and code analyzers, but this provides a high-level example. - -Now that we understand the key terminology, let's dive into some best practices. - -### 1\. Automation is key - -To run CI/CD on a PaaS, you need the proper infrastructure to be configured on the cluster. In this example, I will use [OpenShift][2]. - -"Hello, World" implementations of this are quite simple to achieve. Simply run **oc new-app jenkins- ** and voilà, you have a running Jenkins server ready to go. Uses in the enterprise, however, are much more complex. In addition to the Jenkins server, admins will often need to deploy a code analysis tool such as SonarQube and an artifact repository such as Nexus. They will then have to create pipelines to perform CI/CD and Jenkins slaves to reduce the load on the master. Most of these entities are backed by OpenShift resources that need to be created to deploy the desired CI/CD infrastructure. - -Eventually, the manual steps required to deploy your CI/CD components may need to be replicated, and you might not be the person to perform those steps. To ensure the outcome is produced quickly, error-free, and exactly as it was before, an automation method should be incorporated in the way your infrastructure is created. This can be an Ansible playbook, a Bash script, or any other way you would like to automate the deployment of CI/CD infrastructure. I have used [Ansible][3] and the [OpenShift-Applier][4] role to automate my implementations. You may find these tools valuable, or you may find something else that works better for you and your organization. Either way, you'll find that automation significantly reduces the workload required to recreate CI/CD components. - -#### Configuring the Jenkins master - -Outside of general "automation," I'd like to single out the Jenkins master and talk about a few ways admins can take advantage of OpenShift to automate Jenkins configuration. The Jenkins image from the [Red Hat Container Catalog][5] comes packaged with the [OpenShift-Sync plugin][6] installed. In the [video][7], we discuss how this plugin can be used to create Jenkins pipelines and slaves. - -To create a Jenkins pipeline, create an OpenShift BuildConfig similar to this: - -``` -apiVersion: v1 -kind: BuildConfig -... -spec:   -  source:       -    git:   -      ref: master       -      uri:   -  ...   -  strategy:     -    jenkinsPipelineStrategy:     -      jenkinsfilePath: Jenkinsfile       -    type: JenkinsPipeline -``` - -The OpenShift-Sync plugin will notice that a BuildConfig with the strategy **jenkinsPipelineStrategy** has been created and will convert it into a Jenkins pipeline, pulling from the Jenkinsfile specified by the Git source. An inline Jenkinsfile can also be used instead of pulling from one from a Git repository. See the [documentation][8] for more information. - -To create a Jenkins slave, create an OpenShift ImageStream that starts with the following definition: - -``` -apiVersion: v1 -kind: ImageStream -metadata: -  annotations: -    slave-label: jenkins-slave -    labels: -      role: jenkins-slave -… -``` - -Notice the metadata defined in this ImageStream. The OpenShift-Sync plugin will convert any ImageStream with the label **role: jenkins-slave** into a Jenkins slave. The Jenkins slave will be named after the value from the **slave-label** annotation. - -ImageStreams work just fine for simple Jenkins slave configurations, but some teams will find it necessary to configure nitty-gritty details such as resource limits, readiness and liveness probes, and instance caps. This is where ConfigMaps come into play: - -``` -apiVersion: v1 -kind: ConfigMap -metadata: -  labels: -  role: jenkins-slave -... -data: -  template1: |- -    -``` - -Notice that the **role: jenkins-slave** label is still required to convert the ConfigMap into a Jenkins slave. The **Kubernetes pod template** consists of a lengthy bit of XML that will configure every detail to your organization's liking. To view this XML, as well as more information on converting ImageStreams and ConfigMaps into Jenkins slaves, see the [documentation][9]. - -Notice with the three examples shown above that none of the operations required an administrator to make manual changes to the Jenkins console. By using OpenShift resources, Jenkins can be configured in a way that is easily automated. - -### 2\. Sharing is caring - -The second best practice is maintaining a Git repository of common CI/CD artifacts. The main idea is to prevent teams from reinventing the wheel. Imagine your team needs to perform a blue/green deployment to an OpenShift environment as part of the pipeline's CD phase. The members of your team responsible for writing the pipeline may not be OpenShift experts, nor may they have the bandwidth to write this functionality from scratch. Luckily, somebody has already written a function that incorporates that functionality in a common CI/CD repository, so your team can use that function instead of spending time writing one. - -To take this a step further, your organization may decide to maintain entire pipelines. You may find that teams are writing pipelines with similar functionality. It would be more efficient for those teams to use a parameterized pipeline from a common repository as opposed to writing their own from scratch. - -### 3\. Less is more - -As I hinted in the previous section, the third and final best practice is to parameterize your CI/CD pipelines. Parameterization will prevent an over-abundance of pipelines, making your CI/CD system easier to maintain. Imagine I have multiple regions where I can deploy my application. Without parameterization, I would need a separate pipeline for each region. - -To parameterize a pipeline written as an OpenShift build config, add the **env** stanza to the configuration: - -``` -... -spec: -  ... -  strategy: -    jenkinsPipelineStrategy: -      env: -      - name: REGION -        value: US-West           -      jenkinsfilePath: Jenkinsfile       -    type: JenkinsPipeline -``` - -With this configuration, I can pass the **REGION** parameter the pipeline to deploy my application to the specified region. - -The [video][7] provides a more substantial case where parameterization is a must. Some organizations decide to split up their CI/CD pipelines into separate CI and CD pipelines, usually, because there is some sort of approval process that happens before deployment. Imagine I have four images and three different environments to deploy to. Without parameterization, I would need 12 CD pipelines to allow all deployment possibilities. This can get out of hand very quickly. To make maintenance of the CD pipeline easier, organizations would find it better to parameterize the image and environment to allow one pipeline to perform the work of many. - -### Summary - -CI/CD at the enterprise level tends to become more complex than many organizations anticipate. Luckily, with Jenkins, there are many ways to seamlessly provide automation of your setup. Maintaining a Git repository of common CI/CD artifacts will also ease the effort, as teams can pull from maintained dependencies instead of writing their own from scratch. Finally, parameterization of your CI/CD pipelines will reduce the number of pipelines that will have to be maintained. - -If you've found other practices you can't do without, please share them in the comments. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/11/best-practices-cicd - -作者：[Austin Dewey][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://opensource.com/users/adewey -[b]: https://github.com/lujun9972 -[1]: https://jenkins.io/ -[2]: https://www.openshift.com/ -[3]: https://docs.ansible.com/ -[4]: https://github.com/redhat-cop/openshift-applier -[5]: https://access.redhat.com/containers/?tab=overview#/registry.access.redhat.com/openshift3/jenkins-2-rhel7 -[6]: https://github.com/openshift/jenkins-sync-plugin -[7]: https://www.youtube.com/watch?v=zlL7AFWqzfw -[8]: https://docs.openshift.com/container-platform/3.11/dev_guide/dev_tutorials/openshift_pipeline.html#the-pipeline-build-config -[9]: https://docs.openshift.com/container-platform/3.11/using_images/other_images/jenkins.html#configuring-the-jenkins-kubernetes-plug-in diff --git a/sources/tech/20181119 7 command-line tools for writers - Opensource.com.md b/sources/tech/20181119 7 command-line tools for writers - Opensource.com.md deleted file mode 100644 index a482895af2..0000000000 --- a/sources/tech/20181119 7 command-line tools for writers - Opensource.com.md +++ /dev/null @@ -1,73 +0,0 @@ -7 command-line tools for writers | Opensource.com -====== -Put away your word processor and start writing from the command line using these open source tools. -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/terminal_command_linux_desktop_code.jpg?itok=p5sQ6ODE) - -For most people (especially non-techies), the act of writing means tapping out words using LibreOffice Writer or another GUI word processing application. But there are many other options available to help anyone communicate their message in writing, especially for the growing number of writers [embracing plaintext][1]. - -There's also room in a GUI writer's world for command line tools that can help them write, check their writing, and more—regardless of whether they're banging out an article, blog post, or story; writing a README; or prepping technical documentation. - -Here's a look at some command-line tools that any writer will find useful. - -### Editors - -Yes, you _can_ do actual writing at the command line. I know writers who do their work using editors like [Nano][2], [Vim][3], [Emacs][4], and [Jove][5] in a terminal window. And those editors [aren't the only games in town][6]. Text editors are great because they (at a basic level, anyway) are easy to use and distraction free. They're perfect for tapping out a first draft of anything or even completing a long and complicated writing project. - -If you want a more word processor-like experience at the command line, take a look at [WordGrinder][7] . WordGrinder is a bare-bones word processor, but it has more than enough features for writing and publishing your work. It supports basic formatting and styles, and you can export your writing to formats like Markdown, ODT, LaTeX, and HTML. - -### Spell checkers - -Every writer does (or at least should do) a spelling check on their work at least once. Why? An immutable law of the writing universe states that, no matter how many times you look over your manuscript, a spelling mistake or typo will creep in. - -My favorite command-line spelling checker is [GNU Aspell][8], which I previously [looked at][9] in detail. Aspell checks plaintext documents interactively and not only highlights errors but often puts the best correction at the top of its list of suggestions. Aspell also ignores many markup languages while doing its thing. - -A much older but still useful alternative is [Ispell][10]. It's a bit slower than Aspell, but both utilities work the same way. As you interact with your text file, Ispell suggests corrections. Ispell also has good support for foreign languages. - -### Prose linters - -Software developers use [linters][11] to check their code for errors or bugs. There are also linters for prose that check for style and syntax errors; think of them as the _Elements of Style_ for the command line. While any writer can (and probably should) use one, a prose linter is especially useful for team documentation projects that require a consistent voice and style. - -[Proselint][12] is a comprehensive tool for checking what you're writing. It looks for jargon, hyperbole, incorrect date and time format, misused terms, and [much more][13]. It's also easy to run and ignores markup in a plaintext file. - -[Alex][14] is a simple yet powerful prose linter. Run it against a plaintext document or one formatted with Markdown or HTML. Alex pumps out warnings of "gender favouring, polarising, race related, religion inconsiderate, or other unequal phrasing in text." If you want to give Alex a test drive, there's an [online demo][15]. - -### Other tools - -Sometimes you just can't find the right synonym for a word. But you don't need to grab a "dead tree" thesaurus or go to a dedicated website to perfect your word choice. Just run [Aiksaurus][16] against the word you want to replace, and it does the work for you. This utility's main drawback, though, is that it supports English only. - -Even writers with few (if any) technical skills are embracing [Markdown][17] to quickly and easily format their work. Sometimes, though, you need to convert files formatted with Markdown to something else. That's where [Pandoc][18] comes in. You can use it to convert your documents to HTML, Word, LibreOffice Writer, LaTeX, EPUB, and other formats. You can even use Pandoc to produce books and [research papers][19]. - -Do you have a favorite command-line tool for writing? Share it with the Opensource.com community by leaving a comment. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/11/command-line-tools-writers - -作者：[Scott Nesbitt][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://opensource.com/users/scottnesbitt -[b]: https://github.com/lujun9972 -[1]: https://plaintextproject.online -[2]: https://www.nano-editor.org/ -[3]: https://www.vim.org -[4]: https://www.gnu.org/software/emacs/ -[5]: https://opensource.com/article/17/1/jove-lightweight-alternative-vim -[6]: https://en.wikipedia.org/wiki/List_of_text_editors#Text_user_interface -[7]: https://cowlark.com/wordgrinder/ -[8]: http://aspell.net/ -[9]: https://opensource.com/article/18/2/how-check-spelling-linux-command-line-aspell -[10]: https://www.cs.hmc.edu/~geoff/ispell.html -[11]: https://en.wikipedia.org/wiki/Lint_(software) -[12]: http://proselint.com/ -[13]: http://proselint.com/checks/ -[14]: https://github.com/get-alex/alex -[15]: https://alexjs.com/#demo -[16]: http://aiksaurus.sourceforge.net/ -[17]: https://en.wikipedia.org/wiki/Markdown -[18]: https://pandoc.org -[19]: https://opensource.com/article/18/9/pandoc-research-paper diff --git a/sources/tech/20181119 9 obscure Python libraries for data science.md b/sources/tech/20181119 9 obscure Python libraries for data science.md deleted file mode 100644 index 0250199d7c..0000000000 --- a/sources/tech/20181119 9 obscure Python libraries for data science.md +++ /dev/null @@ -1,258 +0,0 @@ -heguangzhi Translating - -9 obscure Python libraries for data science -====== -Go beyond pandas, scikit-learn, and matplotlib and learn some new tricks for doing data science in Python. -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/life-python.jpg?itok=F2PYP2wT) -Python is an amazing language. In fact, it's one of the fastest growing programming languages in the world. It has time and again proved its usefulness both in developer job roles and data science positions across industries. The entire ecosystem of Python and its libraries makes it an apt choice for users (beginners and advanced) all over the world. One of the reasons for its success and popularity is its set of robust libraries that make it so dynamic and fast. - -In this article, we will look at some of the Python libraries for data science tasks other than the commonly used ones like **pandas, scikit-learn** , and **matplotlib**. Although libraries like **pandas and scikit-learn** are the ones that come to mind for machine learning tasks, it's always good to learn about other Python offerings in this field. - -### Wget - -Extracting data, especially from the web, is one of a data scientist's vital tasks. [Wget][1] is a free utility for non-interactive downloading files from the web. It supports HTTP, HTTPS, and FTP protocols, as well as retrieval through HTTP proxies. Since it is non-interactive, it can work in the background even if the user isn't logged in. So the next time you want to download a website or all the images from a page, **wget** will be there to assist. - -#### Installation - -``` -$ pip install wget -``` - -#### Example - -``` -import wget -url = 'http://www.futurecrew.com/skaven/song_files/mp3/razorback.mp3' - -filename = wget.download(url) -100% [................................................] 3841532 / 3841532 - -filename -'razorback.mp3' -``` - -### Pendulum - -For people who get frustrated when working with date-times in Python, **[Pendulum][2]** is here. It is a Python package to ease **datetime** manipulations. It is a drop-in replacement for Python's native class. Refer to the [documentation][3] for in-depth information. - -#### Installation - -``` -$ pip install pendulum -``` - -#### Example - -``` -import pendulum - -dt_toronto = pendulum.datetime(2012, 1, 1, tz='America/Toronto') -dt_vancouver = pendulum.datetime(2012, 1, 1, tz='America/Vancouver') - -print(dt_vancouver.diff(dt_toronto).in_hours()) - -3 -``` - -### Imbalanced-learn - -Most classification algorithms work best when the number of samples in each class is almost the same (i.e., balanced). But real-life cases are full of imbalanced datasets, which can have a bearing upon the learning phase and the subsequent prediction of machine learning algorithms. Fortunately, the **[imbalanced-learn][4]** library was created to address this issue. It is compatible with [**scikit-learn**][5] and is part of **[scikit-learn-contrib][6]** projects. Try it the next time you encounter imbalanced datasets. - -#### Installation - -``` -pip install -U imbalanced-learn - -# or - -conda install -c conda-forge imbalanced-learn -``` - -#### Example - -For usage and examples refer to the [documentation][7]. - -### FlashText - -Cleaning text data during natural language processing (NLP) tasks often requires replacing keywords in or extracting keywords from sentences. Usually, such operations can be accomplished with regular expressions, but they can become cumbersome if the number of terms to be searched runs into the thousands. - -Python's **[FlashText][8]** module, which is based upon the [FlashText algorithm][9], provides an apt alternative for such situations. The best part of FlashText is the runtime is the same irrespective of the number of search terms. You can read more about it in the [documentation][10]. - -#### Installation - -``` -$ pip install flashtext -``` - -#### Examples - -##### **Extract keywords:** - -``` -from flashtext import KeywordProcessor -keyword_processor = KeywordProcessor() - -# keyword_processor.add_keyword(, ) - -keyword_processor.add_keyword('Big Apple', 'New York') -keyword_processor.add_keyword('Bay Area') -keywords_found = keyword_processor.extract_keywords('I love Big Apple and Bay Area.') - -keywords_found -['New York', 'Bay Area'] -``` - -**Replace keywords:** - -``` -keyword_processor.add_keyword('New Delhi', 'NCR region') - -new_sentence = keyword_processor.replace_keywords('I love Big Apple and new delhi.') - -new_sentence -'I love New York and NCR region.' -``` - -For more examples, refer to the [usage][11] section in the documentation. - -### FuzzyWuzzy - -The name sounds weird, but **[FuzzyWuzzy][12]** is a very helpful library when it comes to string matching. It can easily implement operations like string comparison ratios, token ratios, etc. It is also handy for matching records kept in different databases. - -#### Installation - -``` -$ pip install fuzzywuzzy -``` - -#### Example - -``` -from fuzzywuzzy import fuzz -from fuzzywuzzy import process - -# Simple Ratio - -fuzz.ratio("this is a test", "this is a test!") -97 - -# Partial Ratio -fuzz.partial_ratio("this is a test", "this is a test!") - 100 -``` - -More examples can be found in FuzzyWuzzy's [GitHub repo.][12] - -### PyFlux - -Time-series analysis is one of the most frequently encountered problems in machine learning. **[PyFlux][13]** is an open source library in Python that was explicitly built for working with time-series problems. The library has an excellent array of modern time-series models, including but not limited to **ARIMA** , **GARCH** , and **VAR** models. In short, PyFlux offers a probabilistic approach to time-series modeling. It's worth trying out. - -#### Installation - -``` -pip install pyflux -``` - -#### Example - -Please refer to the [documentation][14] for usage and examples. - -### IPyvolume - -Communicating results is an essential aspect of data science, and visualizing results offers a significant advantage. **[**IPyvolume**][15]** is a Python library to visualize 3D volumes and glyphs (e.g., 3D scatter plots) in the Jupyter notebook with minimal configuration and effort. However, it is currently in the pre-1.0 stage. A good analogy would be something like this: IPyvolume's **volshow** is to 3D arrays what matplotlib's **imshow** is to 2D arrays. You can read more about it in the [documentation][16]. - -#### Installation - -``` -Using pip -$ pip install ipyvolume - -Conda/Anaconda -$ conda install -c conda-forge ipyvolume -``` - -#### Examples - -**Animation:** -![](https://opensource.com/sites/default/files/uploads/ipyvolume_animation.gif) - -**Volume rendering:** -![](https://opensource.com/sites/default/files/uploads/ipyvolume_volume-rendering.gif) - -### Dash - -**[Dash][17]** is a productive Python framework for building web applications. It is written on top of Flask, Plotly.js, and React.js and ties modern UI elements like drop-downs, sliders, and graphs to your analytical Python code without the need for JavaScript. Dash is highly suitable for building data visualization apps that can be rendered in the web browser. Consult the [user guide][18] for more details. - -#### Installation - -``` -pip install dash==0.29.0  # The core dash backend -pip install dash-html-components==0.13.2  # HTML components -pip install dash-core-components==0.36.0  # Supercharged components -pip install dash-table==3.1.3  # Interactive DataTable component (new!) -``` - -#### Example - -The following example shows a highly interactive graph with drop-down capabilities. As the user selects a value in the drop-down, the application code dynamically exports data from Google Finance into a Pandas DataFrame. -![](https://opensource.com/sites/default/files/uploads/dash_animation.gif) - -### Gym - -**[Gym][19]** from [OpenAI][20] is a toolkit for developing and comparing reinforcement learning algorithms. It is compatible with any numerical computation library, such as TensorFlow or Theano. The Gym library is a collection of test problems, also called environments, that you can use to work out your reinforcement-learning algorithms. These environments have a shared interface, which allows you to write general algorithms. - -#### Installation - -``` -pip install gym -``` - -#### Example - -The following example will run an instance of the environment **[CartPole-v0][21]** for 1,000 timesteps, rendering the environment at each step. -![](https://opensource.com/sites/default/files/uploads/gym_animation.gif) - -You can read about [other environments][22] on the Gym website. - -### Conclusion - -These are my picks for useful, but little-known Python libraries for data science. If you know another one to add to this list, please mention it in the comments below. - -This was originally published on the [Analytics Vidhya][23] Medium channel and is reprinted with permission. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/11/python-libraries-data-science - -作者：[Parul Pandey][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://opensource.com/users/parul-pandey -[b]: https://github.com/lujun9972 -[1]: https://pypi.org/project/wget/ -[2]: https://github.com/sdispater/pendulum -[3]: https://pendulum.eustace.io/docs/#installation -[4]: https://github.com/scikit-learn-contrib/imbalanced-learn -[5]: http://scikit-learn.org/stable/ -[6]: https://github.com/scikit-learn-contrib -[7]: http://imbalanced-learn.org/en/stable/api.html -[8]: https://github.com/vi3k6i5/flashtext -[9]: https://arxiv.org/abs/1711.00046 -[10]: https://flashtext.readthedocs.io/en/latest/ -[11]: https://flashtext.readthedocs.io/en/latest/#usage -[12]: https://github.com/seatgeek/fuzzywuzzy -[13]: https://github.com/RJT1990/pyflux -[14]: https://pyflux.readthedocs.io/en/latest/index.html -[15]: https://github.com/maartenbreddels/ipyvolume -[16]: https://ipyvolume.readthedocs.io/en/latest/?badge=latest -[17]: https://github.com/plotly/dash -[18]: https://dash.plot.ly/ -[19]: https://github.com/openai/gym -[20]: https://openai.com/ -[21]: https://gym.openai.com/envs/CartPole-v0 -[22]: https://gym.openai.com/ -[23]: https://medium.com/analytics-vidhya/python-libraries-for-data-science-other-than-pandas-and-numpy-95da30568fad diff --git a/sources/tech/20181119 Arch-Wiki-Man - A Tool to Browse The Arch Wiki Pages As Linux Man Page from Offline.md b/sources/tech/20181119 Arch-Wiki-Man - A Tool to Browse The Arch Wiki Pages As Linux Man Page from Offline.md new file mode 100644 index 0000000000..9e1ee18be7 --- /dev/null +++ b/sources/tech/20181119 Arch-Wiki-Man - A Tool to Browse The Arch Wiki Pages As Linux Man Page from Offline.md @@ -0,0 +1,214 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Arch-Wiki-Man – A Tool to Browse The Arch Wiki Pages As Linux Man Page from Offline) +[#]: via: (https://www.2daygeek.com/arch-wiki-man-a-tool-to-browse-the-arch-wiki-pages-as-linux-man-page-from-offline/) +[#]: author: ([Prakash Subramanian](https://www.2daygeek.com/author/prakash/)) +[#]: url: ( ) + +Arch-Wiki-Man – A Tool to Browse The Arch Wiki Pages As Linux Man Page from Offline +====== + +Getting internet is not a big deal now a days, however there will be a limitation on technology. + +I was really surprise to see the technology growth but in the same time there will be fall in everywhere. + +Whenever you search anything about other Linux distributions most of the time you will get a third party links in the first place but for Arch Linux every time you would get the Arch Wiki page for your results. + +As Arch Wiki has most of the solution other than third party websites. + +As of now, you might used web browser to get a solution for your Arch Linux system but you no need to do the same for now. + +There is a solution is available in command line to perform this action much faster way and the utility called arch-wiki-man. If you are Arch Linux lover, i would suggest you to read **[Arch Linux Post Installation guide][1]** which helps you to tweak your system for day to day use. + +### What is arch-wiki-man? + +[arch-wiki-man][2] tool allows user to search the arch wiki pages right from the command line (CLI) instantly without internet connection. It allows user to access and search an entire wiki pages as a Linux man page. + +Also, you no need to switch to GUI. Updates are pushed automatically every two days so, your local copy of the Arch Wiki pages will be upto date. The tool name is `awman`. awman stands for Arch Wiki Man. + +We had already wrote similar kind of topic called **[Arch Wiki Command Line Utility][3]** (arch-wiki-cli) which allows user search Arch Wiki from command line but make sure you should have internet to use this utility. + +### How to Install arch-wiki-man tool? + +arch-wiki-man utility is available in AUR repository so, we need to use AUR helper to install it. There are many AUR helper is available and we had wrote an article about **[Yaourt AUR helper][4]** and **[Packer AUR helper][5]** which are very famous AUR helper. + +``` +$ yaourt -S arch-wiki-man + +or + +$ packer -S arch-wiki-man +``` + +Alternatively we can install it using npm package manager. Make sure, you should have installed **[NodeJS][6]** on your system. If so, run the following command to install it. + +``` +$ npm install -g arch-wiki-man +``` + +### How to Update the local Arch Wiki copy? + +As updated previously, updates are pushed automatically every two days and it can be done by running the following command. + +``` +$ sudo awman-update +[sudo] password for daygeek: +[email protected] /usr/lib/node_modules/arch-wiki-man +└── [email protected] + +arch-wiki-md-repo has been successfully updated or reinstalled. +``` + +awman-update is faster and more convenient method to get the update. However, you can get the updates by reinstalling this package using the following command. + +``` +$ yaourt -S arch-wiki-man + +or + +$ packer -S arch-wiki-man +``` + +### How to Use Arch Wiki from command line? + +It’s very simple interface and easy to use. To search anything, just run `awman` followed by the search term. The general syntax is as follow. + +``` +$ awman Search-Term +``` + +### How to Search Multiple Matches? + +If you would like to list all the results titles comes with `installation` string, run the following command format. If the output comes with multiple results then you will get a selection menu to navigate each item. + +``` +$ awman installation +``` + +![][8] + +Detailed page screenshot. +![][9] + +### Search a given string in Titles & Descriptions + +The `-d` or `--desc-search` option allow users to search a given string in titles and descriptions. + +``` +$ awman -d mirrors + +or + +$ awman --desc-search mirrors +? Select an article: (Use arrow keys) +❯ [1/3] Mirrors: Related articles + [2/3] DeveloperWiki-NewMirrors: Contents + [3/3] Powerpill: Powerpill is a pac +``` + +### Search a given string in Contents + +The `-k` or `--apropos` option allow users to search a given string in content as well. Make a note, this option significantly slower your search as this scan entire wiki page content. + +``` +$ awman -k openjdk + +or + +$ awman --apropos openjdk +? Select an article: (Use arrow keys) +❯ [1/26] Hadoop: Related articles + [2/26] XDG Base Directory support: Related articles + [3/26] Steam-Game-specific troubleshooting: See Steam/Troubleshooting first. + [4/26] Android: Related articles + [5/26] Elasticsearch: Elasticsearch is a search engine based on Lucene. It provides a distributed, mul.. + [6/26] LibreOffice: Related articles + [7/26] Browser plugins: Related articles +(Move up and down to reveal more choices) +``` + +### Open the search results in a web browser + +The `-w` or `--web` option allow users to open the search results in a web browser. + +``` +$ awman -w AUR helper + +or + +$ awman --web AUR helper +``` + +![][10] + +### Search in other languages + +The `-w` or `--web` option allow users to open the search results in a web browser. To see a list of supported language, run the following command. + +``` +$ awman --list-languages +arabic +bulgarian +catalan +chinesesim +chinesetrad +croatian +czech +danish +dutch +english +esperanto +finnish +greek +hebrew +hungarian +indonesian +italian +korean +lithuanian +norwegian +polish +portuguese +russian +serbian +slovak +spanish +swedish +thai +ukrainian +``` + +Run the awman command with your preferred language to see the results with different language other than English. + +``` +$ awman -l chinesesim deepin +``` + +![][11] + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/arch-wiki-man-a-tool-to-browse-the-arch-wiki-pages-as-linux-man-page-from-offline/ + +作者：[Prakash Subramanian][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/prakash/ +[b]: https://github.com/lujun9972 +[1]: https://www.2daygeek.com/arch-linux-post-installation-30-things-to-do-after-installing-arch-linux/ +[2]: https://github.com/greg-js/arch-wiki-man +[3]: https://www.2daygeek.com/search-arch-wiki-website-command-line-terminal/ +[4]: https://www.2daygeek.com/install-yaourt-aur-helper-on-arch-linux/ +[5]: https://www.2daygeek.com/install-packer-aur-helper-on-arch-linux/ +[6]: https://www.2daygeek.com/install-nodejs-on-ubuntu-centos-debian-fedora-mint-rhel-opensuse/ +[7]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[8]: https://www.2daygeek.com/wp-content/uploads/2018/11/arch-wiki-man-%E2%80%93-A-Tool-to-Browse-The-Arch-Wiki-Pages-As-Linux-Man-page-from-Offline-1.png +[9]: https://www.2daygeek.com/wp-content/uploads/2018/11/arch-wiki-man-%E2%80%93-A-Tool-to-Browse-The-Arch-Wiki-Pages-As-Linux-Man-page-from-Offline-2.png +[10]: https://www.2daygeek.com/wp-content/uploads/2018/11/arch-wiki-man-%E2%80%93-A-Tool-to-Browse-The-Arch-Wiki-Pages-As-Linux-Man-page-from-Offline-3.png +[11]: https://www.2daygeek.com/wp-content/uploads/2018/11/arch-wiki-man-%E2%80%93-A-Tool-to-Browse-The-Arch-Wiki-Pages-As-Linux-Man-page-from-Offline-4.png diff --git a/sources/tech/20181119 How To Customize Bash Prompt In Linux.md b/sources/tech/20181119 How To Customize Bash Prompt In Linux.md deleted file mode 100644 index 267e2b85e2..0000000000 --- a/sources/tech/20181119 How To Customize Bash Prompt In Linux.md +++ /dev/null @@ -1,300 +0,0 @@ -HankChow translating - -How To Customize Bash Prompt In Linux -====== -![](https://www.ostechnix.com/wp-content/uploads/2017/10/BASH-720x340.jpg) - -As you know already, **BASH** (the **B** ourne- **A** gain **Sh** ell) is the default shell for most modern Linux distributions. In this guide, we are going to customize BASH prompt and enhance its look by adding some colors and styles. Of course, there are many plugins/tools available to get this job done easily and quickly. However, we still can do some basic customization, such as adding, modifying elements, changing the foreground and background color etc., without having to install any additional tools and plugins. Let us get started! - -### Customize Bash Prompt In Linux - -In BASH, we can customize and change the BASH prompt as the way you want by changing the value of **PS1** environment variable. - -Usually, the BASH prompt will look something like below: -![](https://www.ostechnix.com/wp-content/uploads/2017/10/Linux-Terminal.png) - -Here, **sk** is my username and **ubuntuserver** is my hostname. - -Now, we are going to change this prompt as per your liking by inserting some backslash-escaped special characters called **Escape Sequences**. - -Let me show you some examples. - -Before going further, it is highly recommended to backup the **~/.bashrc** file. - -``` -$ cp ~/.bashrc ~/.bashrc.bak -``` - -**Modify “[[email protected]][1]” part in the Bash prompt** - -As I mentioned above, the BASH prompt has “[[email protected]][1]” part by default in most Linux distributions. You can change this part to something else. - -To do so, edit **~/.bashrc **file: - -``` -$ vi ~/.bashrc -``` - -Add the following line at the end: - -``` -PS1="ostechnix> " -``` - -Replace “ostechnix” with any letters/words of your choice. Once added, hit the **ESC** key and type **:wq** to save and exit the file. - -Run the following command to update the changes: - -``` -$ source ~/.bashrc -``` - -Now, the BASH prompt will have the letters “ostechnix” in the shell prompt. - -![][3] - -Here is another example. I am going to replace “[[email protected]][1]” part with “[[email protected]][1]>”. - -To do so, add the following entry in your **~./bashrc** file. - -Don’t forget to update the changes using “source ~./bashrc” command. - -Here is the output of my BASH prompt in Ubuntu 18.04 LTS. -![](https://www.ostechnix.com/wp-content/uploads/2017/10/bash-prompt-1.png) - -**Display username only:** - -To display the username only, just add the following line in **~/.bashrc** file. - -``` -export PS1="\u " -``` - -Here, **\u** is the escape sequence. - -Here are some more values to add to your PS1 variable to change the BASH prompt. After adding each entry, you must run “source ~/.bashrc” command to take effect the changes. - -**Add username with hostname:** - -``` -export PS1="\u\h " -``` - -Your prompt will now look like below: - -``` -skubuntuserver -``` - -**Add username and FQDN (Fully Qualified Domain Name):** - -``` -export PS1="\u\H " -``` - -**Add extra characters between username and hostname:** - -If you want to any letter, for example **@** , between the username and hostname, use the following entry: - -``` -export PS1="\u@\h " -``` - -The bash prompt will look like below: -``` -sk@ubuntuserver -``` - -**Add username with hostname with $ symbol at the end:** -``` -export PS1="\u@\h\\$ " -``` - -**Add special characters between and after username and hostname:** -``` -export PS1="\u@\h> " -``` - -This entry will change the BASH prompt as shown below. -``` -sk@ubuntuserver> -``` - -Similarly, you can add other special characters, such as colon, semi-colon, *, underscore, space etc. - -**Display username, hostname, shell name:** -``` -export PS1="\u@\h>\s " -``` - -**Display username, hostname, shell and and its version:** -``` -export PS1="\u@\h>\s\v " -``` - -Bash prompt output: - -![][4] - -Display username, hostname and path to current directory: -``` -export PS1="\u@\h\w " -``` - -You will see a tilde (~) symbol if the current directory is $HOME. - -**Display date in BASH prompt:** - -To display date with your username and hostname in the BASH prompt, add the following entry in ~/.bashrc file. -``` -export PS1="\u@\h>\d " -``` -![][5] - -**Date and time in 12 hour format in BASH prompt:** -``` -export PS1="\u@\h>\d\@ " -``` - -**Date and 12 hour time hh:mm:ss format:** -``` -export PS1="\u@\h>\d\T " -``` - -**Date and 24 hour time:** -``` -export PS1="\u@\h>\d\A " -``` - -**Date and 24 hour hh:mm:ss format:** -``` -export PS1="\u@\h>\d\t " -``` - -These are some common escape sequences to change the Bash prompt format. There are few more escape sequences are available. You can view them all in in the **bash man page** under the **“PROMPTING”** section. - -And, you can view the current prompt settings at any time using command: - -``` -$ echo $PS1 -``` - -**Hide “username@hostname” Part In Bash prompt** - -I don’t want to change anything. Can I hide it altogether? Yes, you can! - -If you’re a blogger or tech writer, there are chances that you have to upload the screenshots of your Linux Terminal in your websites and blogs. Your username/hostname might be too cool, so you may not want others to copy and use them as their own. On the other hand, your username/hostname might be too weird or too bad or contain offensive characters, so you don’t want others to view them. In such cases, this small tip might help you to hide or modify “[[email protected]][1]” part in Terminal. - -If you don’t like to let the users to view your username/hostname part, just follow the steps given below. - -Edit your **“~/.bashrc”** file: - -``` -$ vi ~/.bashrc -``` - -Add the following at the end: - -``` -PS1="\W> " -``` - -Type **:wq** to save and close the file. - -Then, run the following command to take effect the changes. - -``` -$ source ~/.bashrc -``` - -That’s it. Now, check your Terminal. You will not see the [[email protected]][1] part. You will only see the **~ >** symbol. - -![][6] - -Want to know another simplest way without messing the **~/.bashrc** file? Just create another user account something like **[[email protected]][1]** , or **[[email protected]][1]**. Use these accounts for making guides, videos and upload them on your blog or online. Now, you have nothing to worry about your identity. - -**Warning:** This is a bad practice in some cases. For example, if another shells like zsh inherits your current shell, it will cause some problems. Use it only for hiding or modifying your [[email protected]][1] part if you use single shell. Apart from hiding the [[email protected]][1] part in the Terminal, this tip is pretty useless and might be problematic. - -### Colorizing BASH prompt - -What we have seen so far is we just changed/added some elements to the BASH prompt. In this section, we are going to add colors the elements. - -You can enhance the foreground (text) and background color of BASH prompt’s elements by adding some code to the ~/.bashrc file. - -For example, to change the foreground color of all texts to Red, add the following code: -``` -export PS1="\u@\[\e[31m\]\h\[\e[m\] " -``` - -Once added, update the changes using command: - -Now, your BASH prompt will look like below: -![][7] - -Similarly, to change the background color, add this code: -``` -export PS1="\u@\[\e[31;46m\]\h\[\e[m\] " -``` - -![][8] - -### **Adding Emojis** - -Who doesn’t love emoji? We can add an emoji by placing the following code in the ~/.bashrc file. - -``` -PS1="\W 🔥 >" -``` - -Please note that some terminal may not show the emojis properly depending upon the font used. You may see either garbled characters or monochrome emoji if you don’t have suitable fonts. - -### Customizing BASH is bit difficult to me, Is there any other easy way? - -If you’re a newbie, writing and adding PS1 values will be confusing and difficult. Also, you will find it bit difficult to arrange the elements to get the result of your choice. No worries! There is an online Bash PS1 generator available which allows you to easily generate different PS1 values as you wish. - -Go to the following website: - -[![EzPrompt](https://www.ostechnix.com/wp-content/uploads/2017/10/EzPrompt.png)][9] - -Just pick the elements you want to use in your BASH prompt. Add the colors to the elements and re-arrange them in any order of your liking. Preview the output instantly and finally copy/paste resulting code in your **~/.bashrc** file. It is that simple! Most of the examples mentioned in this guide are taken from this website. - - -### I messed up with my .bashrc file? How to restore it to default settings? - -As I mentioned earlier, it is strongly recommended to take backup ~./bashrc (Or any important configuration files in general) before making any changes. So, you can restore it to the previous working version if something went wrong. However if you forgot to backup the ~/.bashrc file in the first place, you still can restore it to the default settings as described in the following guide. - -[How To Restore .bashrc File To Default Settings][10] - -The above guide is based on Ubuntu, but it may applicable to other Linux distributions as well. Please let us be clear that the aforementioned guide will help you to reset ~/.bashrc to its default settings at the time of new installation. Any changes done afterwards will be lost. - -And, that’s all for now. I will keep updating this guide as I learned more ways to customize the BASH prompt in future. - -Hope this helps. More good stuffs to come. Stay tuned! - -Cheers! - - - --------------------------------------------------------------------------------- - -via: https://www.ostechnix.com/hide-modify-usernamelocalhost-part-terminal/ - -作者：[SK][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://www.ostechnix.com/author/sk/ -[b]: https://github.com/lujun9972 -[1]: https://www.ostechnix.com/cdn-cgi/l/email-protection -[2]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 -[3]: http://www.ostechnix.com/wp-content/uploads/2017/10/Linux-Terminal-2.png -[4]: http://www.ostechnix.com/wp-content/uploads/2017/10/bash-prompt-2.png -[5]: http://www.ostechnix.com/wp-content/uploads/2017/10/bash-prompt-3.png -[6]: http://www.ostechnix.com/wp-content/uploads/2017/10/Linux-Terminal-1.png -[7]: http://www.ostechnix.com/hide-modify-usernamelocalhost-part-terminal/bash-prompt-4/ -[8]: http://www.ostechnix.com/hide-modify-usernamelocalhost-part-terminal/bash-prompt-5/ -[9]: http://ezprompt.net/ -[10]: https://www.ostechnix.com/restore-bashrc-file-default-settings-ubuntu/ diff --git a/sources/tech/20181120 How To Change GDM Login Screen Background In Ubuntu.md b/sources/tech/20181120 How To Change GDM Login Screen Background In Ubuntu.md deleted file mode 100644 index 1b35fd563d..0000000000 --- a/sources/tech/20181120 How To Change GDM Login Screen Background In Ubuntu.md +++ /dev/null @@ -1,85 +0,0 @@ -Translating by Guevaraya -How To Change GDM Login Screen Background In Ubuntu -====== -Whenever you log in or lock and unlock your Ubuntu 18.04 LTS desktop, you will be greeted with a plain purple-colored screen. It is the default GDM (GNOME Display Manager) background since Ubuntu version 17.04. Some of you may feel boring to look at this plain background and want to make the Login screen something cool and eye-candy! If so, you’re on the right track. This brief guide describes how to change GDM Login screen background in Ubuntu 18.04 LTS desktop. - -### Change GDM Login Screen Background In Ubuntu - -Here is how the default GDM login screen background image looks like in Ubuntu 18.04 LTS desktop. -![](https://www.ostechnix.com/wp-content/uploads/2018/11/GDM-login-screen-1.png) - -Whether you like it or not, you will stumbled upon this screen every time you log in or lock and unlock the system. No worries! You can change this background with any beautiful image of your choice. - -Changing desktop wallpaper and user’s profile picture is not a big deal in Ubuntu. We can do it with a few mouse clicks in no time. However, changing Login/Lock screen background need a little bit editing of a file called **ubuntu.css** located under **/usr/share/gnome-shell/theme** directory. - -Before modifying this file, take a backup of this file. So, we can restore it if something went wrong. - -``` -$ sudo cp /usr/share/gnome-shell/theme/ubuntu.css /usr/share/gnome-shell/theme/ubuntu.css.bak -``` - -Now, edit ubuntu.css file: - -``` -$ sudo nano /usr/share/gnome-shell/theme/ubuntu.css -``` - -Find the following lines under the directive named **“lockDialogGroup”** in the file: - -``` -#lockDialogGroup { - background: #2c001e url(resource:///org/gnome/shell/theme/noise-texture.png); - background-repeat: repeat; -} -``` -![](https://www.ostechnix.com/wp-content/uploads/2018/11/ubuntu_css.png) - -As you can see, the default image for the GDM login screen is **noise-texture.png**. - -Now, change the background image by adding your image path. You can use either .jpg or .png file. Both format images worked fine for me. After editing the file, the contents of file will look like below: - -``` -#lockDialogGroup { - background: #2c001e url(file:///home/sk/image.png); - background-repeat: no-repeat; - background-size: cover; - background-position: center; -} -``` - -Please pay little attention to the modified version of this directive in the ubuntu.css file. I have marked the changes in bold. - -As you might have noticed, I have changed the line “… **url(resource:///org/gnome/shell/theme/noise-texture.png);** ” with “ **…url(file:///home/sk/image.png);”**. I.e You should change “… **url(resource** …” to “… **url(file**..”. - -Also, I have changed the value of “background-repeat:” parameter from **“repeat”** to **“no-repeat”** and added two more lines. You can simply copy/paste the above lines and change image path with your own in your ubuntu.css file. - -Once you are done, save and close the file. And, reboot your system. - -Here is my GDM login screen with updated backgrounds: -![](https://www.ostechnix.com/wp-content/uploads/2018/11/GDM-login-screen-2.png) - -![](https://www.ostechnix.com/wp-content/uploads/2018/11/GDM-login-screen-3.png) - -Cool, yeah? As you can see, changing GDM login screen is not that difficult either. All you have to do is to change the path of the image in ubuntu.css file and restart your system. It is simple as that. Have fun! - -You can also edit **gdm3.css** file located under **/usr/share/gnome-shell/theme** directory and modify it as shown above to get the same result. Again, don’t forget to take the backup of the file before making any changes. - -And, that’s all now. More good stuffs to come. Stay tuned! - -Cheers! - - - --------------------------------------------------------------------------------- - -via: https://www.ostechnix.com/how-to-change-gdm-login-screen-background-in-ubuntu/ - -作者：[SK][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://www.ostechnix.com/author/sk/ -[b]: https://github.com/lujun9972 diff --git a/sources/tech/20181122 Getting started with Jenkins X.md b/sources/tech/20181122 Getting started with Jenkins X.md new file mode 100644 index 0000000000..1c2aab6903 --- /dev/null +++ b/sources/tech/20181122 Getting started with Jenkins X.md @@ -0,0 +1,148 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Getting started with Jenkins X) +[#]: via: (https://opensource.com/article/18/11/getting-started-jenkins-x) +[#]: author: (Dave Johnson https://opensource.com/users/snoopdave) +[#]: url: ( ) + +Getting started with Jenkins X +====== +Jenkins X provides continuous integration, automated testing, and continuous delivery to Kubernetes. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/ship_wheel_gear_devops_kubernetes.png?itok=xm4a74Kv) + +[Jenkins X][1] is an open source system that offers software developers continuous integration, automated testing, and continuous delivery, known as CI/CD, in Kubernetes. Jenkins X-managed projects get a complete CI/CD process with a Jenkins pipeline that builds and packages project code for deployment to Kubernetes and access to pipelines for promoting projects to staging and production environments. + +Developers are already benefiting from running "classic" open source Jenkins and CloudBees Jenkins on Kubernetes, thanks in part to the Jenkins Kubernetes plugin, which allows you to dynamically spin-up Kubernetes pods to run Jenkins build agents. Jenkins X adds what's missing from Jenkins: comprehensive support for continuous delivery and managing the promotion of projects to preview, staging, and production environments running in Kubernetes. + +This article is a high-level explanation of how Jenkins X works; it assumes you have some knowledge of Kubernetes and classic Jenkins. + +### What you get with Jenkins X + +If you're running on one of the major cloud providers (Amazon Elastic Container Service for Kubernetes, Google Kubernetes Engine, or Microsoft Azure Kubernetes Service), installing and deploying Jenkins X is easy. Download the Jenkins X command-line interface and run the **jx create cluster** command. You'll be prompted for the necessary information and, if you take the defaults, Jenkins X will create a starter-size Kubernetes cluster and install Jenkins X. + +When you deploy Jenkins X, a number of services are put in motion to watch your Git repositories and respond by building, testing, and promoting your applications to staging, production, and other environments you define. Jenkins X also deploys a set of supporting services, including [Jenkins][2], [Docker Registry][3], [Chart Museum][4], and [Monocular][5] to manage [Helm][6] charts, and [Nexus][7], which serves as a Maven and npm repository. + +The Jenkins X deployment also creates two Git repositories, one for your staging environment and one for production. These are in addition to the Git repositories you use to manage your project source code. Jenkins X uses these repositories to manage what is deployed to each environment, and promotions are done via Git pull requests (PRs)—this approach is known as [GitOps][8]. Each repository contains a Helm chart that specifies the applications to be deployed to the corresponding environment. Each repository also has a Jenkins pipeline to handle promotions. + +### Creating a new project with Jenkins X + +To create a new project with Jenkins X, use the **jx create quickstart** command. If you don't specify any options, jx will prompt you to select a project name and a platform—which can be just about anything. SpringBoot, Go, Python, Node, ASP.NET, Rust, Angular, and React are all supported, and the list keeps growing. Once you have chosen your project name and platform, Jenkins X will: + + * Create a new project that includes a "hello-world"-style web project + * Add the appropriate type of makefile or build script for the chosen platform + * Add a Jenkinsfile to manage promotions to staging and production environments + * Add a Dockerfile and Helm charts, created via [Draft][9] + * Add a [Skaffold][10] configuration for deploying the application to Kubernetes + * Create a Git repository and push the new project code there + + + +Next, a webhook from Git will notify Jenkins X that a project changed, and it will run your project's Jenkins pipeline to build and push your Docker image and Helm charts. + +Finally, the pipeline will submit a PR to the staging environment's Git repository with the changes needed to promote the application. + +Once the PR is merged, the staging pipeline will run to apply those changes and do the promotion. A couple of minutes after creating your project, you'll have end-to-end CI/CD, and your project will be running in staging and available for use. + +![Developer commits changes, project deployed to staging][12] + +Developer commits changes, project deployed to the staging environment. + +The figure above illustrates the repositories, registries, and pipelines and how they interact in a Jenkins X promotion to staging. Here are the steps: + + 1. The developer commits and pushes the change to the project's Git repository + 2. Jenkins X is notified and runs the project's Jenkins pipeline in a Docker image that includes the project's language and supporting frameworks + 3. The project pipeline builds, tests, and pushes the project's Helm chart to Chart Museum and its Docker image to the registry + 4. The project pipeline creates a PR with changes needed to add the project to the staging environment + 5. Jenkins X automatically merges the PR to Master + 6. Jenkins X is notified and runs the staging pipeline + 7. The staging pipeline runs Helm, which deploys the environment, pulling Helm charts from Chart Museum and Docker images from the Docker registry. Kubernetes creates the project's resources, typically a pod, service, and ingress. + + + +### Importing your existing projects into Jenkins X + +**jx import** , Jenkins X adds the things needed for your project to be deployed to Kubernetes and participate in CI/CD. It will add a Jenkins pipeline, Helm charts, and a Skaffold configuration for deploying the application to Kubernetes. Jenkins X will create a Git repository and push the changes there. Next, a webhook from Git will notify Jenkins X that a project changed, and promotion to staging will happen as described above for new projects. + +### Promoting your project to production + +When you import a project via, Jenkins X adds the things needed for your project to be deployed to Kubernetes and participate in CI/CD. It will add a Jenkins pipeline, Helm charts, and a Skaffold configuration for deploying the application to Kubernetes. Jenkins X will create a Git repository and push the changes there. Next, a webhook from Git will notify Jenkins X that a project changed, and promotion to staging will happen as described above for new projects. + +To promote a version of your project to the production environment, use the **jx promote** command. This command will prepare a Git PR that contains the Helm chart changes needed to deploy into the production environment and submit this request to the production environment's Git repository. Once the request is manually approved, Jenkins X will run the production pipeline to deploy your project via Helm. + +![Promoting project to production][14] + +Developer promotes the project to production. + +This figure illustrates the repositories, registries, and pipelines and how they interact in a Jenkins X promotion to production. Here are the steps: + + 1. The developer runs the **jx promote** command to promote a project to production + 2. Jenkins X creates a PR with changes needed to add the project to the production environment + 3. The developer manually approves the PR, and it is merged to Master + 4. Jenkins X is notified and runs the production pipeline + 5. The production pipeline runs Helm, which deploys the environment, pulling Helm charts from Chart Museum and Docker images from the Docker registry. Kubernetes creates the project's resources, typically a pod, service, and ingress. + + + +### Other features of Jenkins X + +Other interesting and appealing features of Jenkins X include: + +#### Preview environments + +When you create a PR to add a new feature to your project, you can ask Jenkins X to create a preview environment so you can make your new feature available for preview and testing before the PR is merged. + +#### Extensions + +It is possible to create extensions to Jenkins X. An extension is code that runs at specific times in the CI/CD process. An extension can provide code that runs when the extension is installed, uninstalled, as well as before and after each pipeline. + +#### Serverless Jenkins + +Instead of running the Jenkins web application, which continually consumes CPU and memory resources, you can run Jenkins only when you need it. During the past year, the Jenkins community created a version of Jenkins that can run classic Jenkins pipelines via the command line with the configuration defined by code instead of HTML forms. + +This capability is now available in Jenkins X. When you create a Jenkins X cluster, you can choose to use Serverless Jenkins. If you do, Jenkins X will deploy [Prow][15] to handle webhooks from GitHub and [Knative][16] to run Jenkins pipelines. + +### Jenkins X limitations + +Jenkins X also has some limitations that should be considered: + + * **Jenkins X is currently limited to projects that use Git:** Jenkins X is opinionated about CI/CD and assumes everybody wants to run and deploy software to Kubernetes and everybody is happy to use Git for source code and defining environments. Also, the Serverless Jenkins feature currently works only with GitHub. + * **Jenkins X is limited to Kubernetes:** It is true that Jenkins X can run automated builds, testing, and continuous integration for any type of software, but the continuous delivery part targets a Kubernetes namespace managed by Jenkins X. + * **Jenkins X requires cluster-admin level Kubernetes access:** Jenkins X needs cluster-admin access so it can define and manage a Kubernetes custom resource definition. Hopefully, this is a temporary limitation, because it could be a show-stopper for some. + + + +### Conclusions + +Jenkins X looks to be a good way to implement CI/CD for Kubernetes, and I'm looking forward to putting it to the test in production. Using Jenkins X is also a good way to learn about some useful open source tools for deploying to Kubernetes, including Helm, Draft, Skaffold, Prow, and more. These are things you might want to use even if you decide Jenkins X is not for you. If you're deploying to Kubernetes, take Jenkins X for a spin. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/11/getting-started-jenkins-x + +作者：[Dave Johnson][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/snoopdave +[b]: https://github.com/lujun9972 +[1]: https://jenkins-x.io/ +[2]: https://jenkins.io/ +[3]: https://docs.docker.com/registry/ +[4]: https://github.com/helm/chartmuseum +[5]: https://github.com/helm/monocular +[6]: https://helm.sh +[7]: https://www.sonatype.com/nexus-repository-oss +[8]: https://www.weave.works/blog/gitops-operations-by-pull-request +[9]: https://draft.sh/ +[10]: https://github.com/GoogleContainerTools/skaffold +[11]: /file/414941 +[12]: https://opensource.com/sites/default/files/uploads/jenkinsx_fig1.png (Developer commits changes, project deployed to staging) +[13]: /file/414946 +[14]: https://opensource.com/sites/default/files/uploads/jenkinsx_fig2.png (Promoting project to production) +[15]: https://github.com/kubernetes/test-infra/tree/master/prow +[16]: https://cloud.google.com/knative/ diff --git a/sources/tech/20181123 How to Build a Netboot Server, Part 1.md b/sources/tech/20181123 How to Build a Netboot Server, Part 1.md deleted file mode 100644 index 980ccba78c..0000000000 --- a/sources/tech/20181123 How to Build a Netboot Server, Part 1.md +++ /dev/null @@ -1,466 +0,0 @@ -[^#]: collector: lujun9972 -[^#]: translator: -[^#]: reviewer: -[^#]: publishor: -[^#]: subject: How to Build a Netboot Server, Part 1 -[^#]: via: https://fedoramagazine.org/how-to-build-a-netboot-server-part-1/ -[^#]: author: [Gregory Bartholomew](https://fedoramagazine.org/author/glb/) -[^#]: url: - -How to Build a Netboot Server, Part 1 -====== - -![](https://fedoramagazine.org/wp-content/uploads/2018/11/build-netboot-816x345.jpg) - -Some computer networks need to maintain identical software installations and configurations on several physical machines. One such environment would be a school computer lab. A [netboot][1] server can be set up to serve an entire operating system over a network so that the client computers can be configured from one central location. This tutorial will show one method of building a netboot server. - -Part 1 of this tutorial will cover creating a netboot server and image. Part 2 will show how to add Kerberos-authenticated home directories to the netboot configuration. - -### Initial Configuration - -Start by downloading one of Fedora Server’s [netinst][2] images, burning it to a CD, and booting the server that will be reformatted from it. We just need a typical “Minimal Install” of Fedora Server for our starting point and we will use the command line to add any additional packages that are needed after the installation is finished. - -![][3] - -> NOTE: For this tutorial we will be using Fedora 28. Other versions may include a slightly different set of packages in their “Minimal Install”. If you start with a different version of Fedora, then you may need to do some troubleshooting if an expected file or command is not available. - -Once you have your minimal installation of Fedora Server up and running, log in as root and set the hostname: - -``` -$ MY_HOSTNAME=server-01.example.edu -$ hostnamectl set-hostname $MY_HOSTNAME -``` - -> NOTE: Red Hat recommends that both static and transient names match the fully-qualified domain name (FQDN) used for the machine in DNS, such as host.example.com ([Understanding Host Names][4]). -> -> NOTE: This guide is meant to be copy-and-paste friendly. Any value that you might need to customize will be stated as a MY_* variable that you can tweak before running the remaining commands. Beware that if you log out, the variable assignments will be cleared. -> -> NOTE: Fedora 28 Server tends to dump a lot of logging output to the console by default. You may want to disable the console logging temporarily by running: sysctl -w kernel.printk=0 - -Next, we need a static network address on our server. The following sequence of commands should find and reconfigure your default network connection appropriately: - -``` -$ MY_DNS1=192.0.2.91 -$ MY_DNS2=192.0.2.92 -$ MY_IP=192.0.2.158 -$ MY_PREFIX=24 -$ MY_GATEWAY=192.0.2.254 -$ DEFAULT_DEV=$(ip route show default | awk '{print $5}') -$ DEFAULT_CON=$(nmcli d show $DEFAULT_DEV | sed -n '/^GENERAL.CONNECTION:/s!.*:\s*!! p') -$ nohup bash << END -nmcli con mod "$DEFAULT_CON" connection.id "$DEFAULT_DEV" -nmcli con mod "$DEFAULT_DEV" connection.interface-name "$DEFAULT_DEV" -nmcli con mod "$DEFAULT_DEV" ipv4.method disabled -nmcli con up "$DEFAULT_DEV" -nmcli con add con-name br0 ifname br0 type bridge -nmcli con mod br0 bridge.stp no -nmcli con mod br0 ipv4.dns $MY_DNS1,$MY_DNS2 -nmcli con mod br0 ipv4.addresses $MY_IP/$MY_PREFIX -nmcli con mod br0 ipv4.gateway $MY_GATEWAY -nmcli con mod br0 ipv4.method manual -nmcli con up br0 -nmcli con add con-name br0-slave0 ifname "$DEFAULT_DEV" type bridge-slave master br0 -nmcli con up br0-slave0 -END -``` - -> NOTE: The last set of commands above is wrapped in a “nohup” script because it will disable networking temporarily. The nohup command should allow the nmcli commands to finish running even while your ssh connection is down. Beware that it may take 10 or so seconds for the connection to come back up and that you will have to start a new ssh connection if you changed the server’s IP address. -> -> NOTE: The above network configuration creates a [network bridge][5] on top of the default connection so that we can run a virtual machine instance directly on the server for testing later. If you do not want to test the netboot image directly on the server, you can skip creating the bridge and set the static IP address directly on your default network connection. - -### Install and Configure NFS4 - -Start by installing the nfs-utils package: - -``` -$ dnf install -y nfs-utils -``` - -Create a top-level [pseudo filesystem][6] for the NFS exports and share it out to your network: - -``` -$ MY_SUBNET=192.0.2.0 -$ mkdir /export -$ echo "/export -fsid=0,ro,sec=sys,root_squash $MY_SUBNET/$MY_PREFIX" > /etc/exports -``` - -SELinux will interfere with the netboot server’s operation. Configuring exceptions for it is beyond the scope of this tutorial, so we will disable it: - -``` -$ sed -i '/GRUB_CMDLINE_LINUX/s/"$/ audit=0 selinux=0"/' /etc/default/grub -$ grub2-mkconfig -o /boot/grub2/grub.cfg -$ sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/sysconfig/selinux -$ setenforce 0 -``` - -> NOTE: Editing the grub command line should not be necessary, but simply editing /etc/sysconfig/selinux proved ineffective across reboots of Fedora Server 28 during testing, so the “selinux=0” flag has been set here to be doubly sure. - -Now, add an exception for the NFS service to the local firewall and start the NFS service: - -``` -$ firewall-cmd --add-service nfs -$ firewall-cmd --runtime-to-permanent -$ systemctl enable nfs-server.service -$ systemctl start nfs-server.service -``` - -### Create the Netboot Image - -Now that our NFS server is up and running, we need to supply it with an operating system image to serve to the client computers. We will start with a very minimal image and add to it after everything is working. - -First, create a new directory where our image will be stored: - -``` -$ mkdir /fc28 -``` - -Use the “dnf” command to build the image under the new directory with only a few base packages: - -``` -$ dnf -y --releasever=28 --installroot=/fc28 install fedora-release systemd passwd rootfiles sudo dracut dracut-network nfs-utils vim-minimal dnf -``` - -It is important that the “kernel” packages were omitted from the above command. Before they are installed, we need to tweak the set of drivers that will be included in the “initramfs” image that is built automatically when the kernel is first installed. In particular, we need to disable “hostonly” mode so that the initramfs image will work on a wider set of hardware platforms and we need to add support for networking and NFS: - -``` -$ echo 'hostonly=no' > /fc28/etc/dracut.conf.d/hostonly.conf -$ echo 'add_dracutmodules+=" network nfs "' > /fc28/etc/dracut.conf.d/netboot.conf -``` - -Now, install the kernel: - -``` -$ dnf -y --installroot=/fc28 install kernel -``` - -Set a rule to prevent the kernel from being updated: - -``` -$ echo 'exclude=kernel-*' >> /fc28/etc/dnf/dnf.conf -``` - -Set the locale: - -``` -$ echo 'LANG="en_US.UTF-8"' > /fc28/etc/locale.conf -``` - -> NOTE: Some programs (e.g. GNOME Terminal) will not function if the locale is not properly configured. - -Blank root’s passwd: - -``` -$ sed -i 's/^root:\*/root:/' /fc28/etc/shadow -``` - -Set the client’s hostname: - -``` -$ MY_CLIENT_HOSTNAME=client-01.example.edu -$ echo $MY_CLIENT_HOSTNAME > /fc28/etc/hostname -``` - -Disable logging to the console: - -``` -$ echo 'kernel.printk = 0 4 1 7' > /fc28/etc/sysctl.d/00-printk.conf -``` - -Define a local “liveuser” in the netboot image: - -``` -$ echo 'liveuser:x:1000:1000::/home/liveuser:/bin/bash' >> /fc28/etc/passwd -$ echo 'liveuser::::::::' >> /fc28/etc/shadow -$ echo 'liveuser:x:1000:' >> /fc28/etc/group -$ echo 'liveuser:!::' >> /fc28/etc/gshadow -``` - -Allow “liveuser” to sudo: - -``` -$ echo 'liveuser ALL=(ALL) NOPASSWD: ALL' > /fc28/etc/sudoers.d/liveuser -``` - -Enable automatic home directory creation: - -``` -$ dnf install -y --installroot=/fc28 authselect oddjob-mkhomedir -$ echo 'dirs /home' > /fc28/etc/rwtab.d/home -$ chroot /fc28 authselect select sssd with-mkhomedir --force -$ chroot /fc28 systemctl enable oddjobd.service -``` - -Since multiple clients will be mounting our image concurrently, we need to configure the image so that it will operate in read-only mode: - -``` -$ sed -i 's/^READONLY=no$/READONLY=yes/' /fc28/etc/sysconfig/readonly-root -``` - -Configure logging to go to RAM rather than permanent storage: - -``` -$ sed -i 's/^#Storage=auto$/Storage=volatile/' /fc28/etc/systemd/journald.conf -``` - -Configure DNS: - -``` -$ MY_DNS1=192.0.2.91 -$ MY_DNS2=192.0.2.92 -$ cat << END > /fc28/etc/resolv.conf -nameserver $MY_DNS1 -nameserver $MY_DNS2 -END -``` - -Work-around a few bugs that exist for read-only root mounts at the time this tutorial is being written ([BZ1542567][7]): - -``` -$ echo 'dirs /var/lib/gssproxy' > /fc28/etc/rwtab.d/gssproxy -$ cat << END > /fc28/etc/rwtab.d/systemd -dirs /var/lib/systemd/catalog -dirs /var/lib/systemd/coredump -END -``` - -Finally, we can create the NFS filesystem for our image and share it out to our subnet: - -``` -$ mkdir /export/fc28 -$ echo '/fc28 /export/fc28 none bind 0 0' >> /etc/fstab -$ mount /export/fc28 -$ echo "/export/fc28 -ro,sec=sys,no_root_squash $MY_SUBNET/$MY_PREFIX" > /etc/exports.d/fc28.exports -$ exportfs -vr -``` - -### Create the Boot Loader - -Now that we have an operating system available to netboot, we need a boot loader to kickstart it on the client systems. For this setup, we will be using [iPXE][8]. - -> NOTE: This section and the following section — Testing with QEMU — can be done on a separate computer; they do not have to be run on the netboot server. - -Install git and use it to download iPXE: - -``` -$ dnf install -y git -$ git clone http://git.ipxe.org/ipxe.git $HOME/ipxe -``` - -Now we need to create a special startup script for our bootloader: - -``` -$ cat << 'END' > $HOME/ipxe/init.ipxe -#!ipxe - -prompt --key 0x02 --timeout 2000 Press Ctrl-B for the iPXE command line... && shell || - -dhcp || exit -set prefix file:///linux -chain ${prefix}/boot.cfg || exit -END -``` - -Enable the “file” download protocol: - -``` -$ echo '#define DOWNLOAD_PROTO_FILE' > $HOME/ipxe/src/config/local/general.h -``` - -Install the C compiler and related tools and libraries: - -``` -$ dnf groupinstall -y "C Development Tools and Libraries" -``` - -Build the boot loader: - -``` -$ cd $HOME/ipxe/src -$ make clean -$ make bin-x86_64-efi/ipxe.efi EMBED=../init.ipxe -``` - -Make note of where the where the newly-compiled boot loader is. We will need it for the next section: - -``` -$ IPXE_FILE="$HOME/ipxe/src/bin-x86_64-efi/ipxe.efi" -``` - -### Testing with QEMU - -This section is optional, but you will need to duplicate the file layout of the [EFI system partition][9] that is shown below on your physical machines to configure them for netbooting. - -> NOTE: You could also copy the files to a TFTP server and reference that server from DHCP if you wanted a fully diskless system. - -In order to test our boot loader with QEMU, we are going to create a small disk image containing only an EFI system partition and our startup files. - -Start by creating the required directory layout for the EFI system partition and copying the boot loader that we created in the previous section to it: - -``` -$ mkdir -p $HOME/esp/efi/boot -$ mkdir $HOME/esp/linux -$ cp $IPXE_FILE $HOME/esp/efi/boot/bootx64.efi -``` - -The below command should identify the kernel version that our netboot image is using and store it in a variable for use in the remaining configuration directives: - -``` -$ DEFAULT_VER=$(ls -c /fc28/lib/modules | head -n 1) -``` - -Define the boot configuration that our client computers will be using: - -``` -$ MY_DNS1=192.0.2.91 -$ MY_DNS2=192.0.2.92 -$ MY_NFS4=server-01.example.edu -$ cat << END > $HOME/esp/linux/boot.cfg -#!ipxe - -kernel --name kernel.efi \${prefix}/vmlinuz-$DEFAULT_VER initrd=initrd.img ro ip=dhcp rd.peerdns=0 nameserver=$MY_DNS1 nameserver=$MY_DNS2 root=nfs4:$MY_NFS4:/fc28 console=tty0 console=ttyS0,115200n8 audit=0 selinux=0 quiet -initrd --name initrd.img \${prefix}/initramfs-$DEFAULT_VER.img -boot || exit -END -``` - -> NOTE: The above boot script shows a minimal example of how to get iPXE to netboot Linux. Much more complex configurations are possible. Most notably, iPXE has support for interactive boot menus which can be configured with a default selection and a timeout. A more advanced iPXE script could, for example, default to booting an operation system from the local disk and only go to the netboot operation if a user pressed a key before a countdown timer reached zero. - -Copy the Linux kernel and its associated initramfs to the EFI system partition: - -``` -$ cp $(find /fc28/lib/modules -maxdepth 2 -name 'vmlinuz' | grep -m 1 $DEFAULT_VER) $HOME/esp/linux/vmlinuz-$DEFAULT_VER -$ cp $(find /fc28/boot -name 'init*' | grep -m 1 $DEFAULT_VER) $HOME/esp/linux/initramfs-$DEFAULT_VER.img -``` - -Our resulting directory layout should look like this: - -``` -esp -├── efi -│   └── boot -│   └── bootx64.efi -└── linux - ├── boot.cfg - ├── initramfs-4.18.18-200.fc28.x86_64.img - └── vmlinuz-4.18.18-200.fc28.x86_64 -``` - -To use our EFI system partition with QEMU, we need to create a small “uefi.img” disk image containing it and then connect that to QEMU as the primary boot drive. - -Begin by installing the necessary tools: - -``` -$ dnf install -y parted dosfstools -``` - -Now create the “uefi.img” file and copy the files from the “esp” directory into it: - -``` -$ ESP_SIZE=$(du -ks $HOME/esp | cut -f 1) -$ dd if=/dev/zero of=$HOME/uefi.img count=$((${ESP_SIZE}+5000)) bs=1KiB -$ UEFI_DEV=$(losetup --show -f $HOME/uefi.img) -$ parted ${UEFI_DEV} -s mklabel gpt mkpart EFI FAT16 1MiB 100% toggle 1 boot -$ mkfs -t msdos ${UEFI_DEV}p1 -$ mkdir -p $HOME/mnt -$ mount ${UEFI_DEV}p1 $HOME/mnt -$ cp -r $HOME/esp/* $HOME/mnt -$ umount $HOME/mnt -$ losetup -d ${UEFI_DEV} -``` - -> NOTE: On a physical computer, you need only copy the files from the “esp” directory to the computer’s existing EFI system partition. You do not need the “uefi.img” file to boot a physical computer. -> -> NOTE: On a physical computer you can rename the “bootx64.efi” file if a file by that name already exists, but if you do so, you will probably have to edit the computer’s BIOS settings and add the renamed efi file to the boot list. - -Next we need to install the qemu package: - -``` -$ dnf install -y qemu-system-x86 -``` - -Allow QEMU to access the bridge that we created in the “Initial Configuration” section of this tutorial: - -``` -$ echo 'allow br0' > /etc/qemu/bridge.conf -``` - -Create a copy of the “OVMF_VARS.fd” image to store our virtual machine’s persistent BIOS settings: - -``` -$ cp /usr/share/edk2/ovmf/OVMF_VARS.fd $HOME -``` - -Now, start the virtual machine: - -``` -$ qemu-system-x86_64 -machine accel=kvm -nographic -m 1024 -drive if=pflash,format=raw,unit=0,file=/usr/share/edk2/ovmf/OVMF_CODE.fd,readonly=on -drive if=pflash,format=raw,unit=1,file=$HOME/OVMF_VARS.fd -drive if=ide,format=raw,file=$HOME/uefi.img -net bridge,br=br0 -net nic,model=virtio -``` - -If all goes well, you should see results similar to what is shown in the below image: - -![][10] -You can use the “shutdown” command to get out of the virtual machine and back to the server: - -``` -$ sudo shutdown -h now -``` - -> NOTE: If something goes wrong and the virtual machine hangs, you may need to start a new ssh session to the server and use the “kill” command to terminate the “qemu-system-x86_64” process. - -### Adding to the Image - -Adding to the image should be a simple matter of chroot’ing into the image on the server and running “dnf install ”. - -There is no limit to what can be installed on the netboot image. A full graphical installation should function perfectly. - -Here is an example of how to bring our minimal netboot image up to a complete graphical installation: - -``` -$ for i in dev dev/pts dev/shm proc sys run; do mount -o bind /$i /fc28/$i; done -$ chroot /fc28 /usr/bin/bash --login -$ dnf -y groupinstall "Fedora Workstation" -$ dnf -y remove gnome-initial-setup -$ systemctl disable sshd.service -$ systemctl enable gdm.service -$ systemctl set-default graphical.target -$ sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/sysconfig/selinux -$ logout -$ for i in run sys proc dev/shm dev/pts dev; do umount /fc28/$i; done -``` - -Optionally, you may want to enable automatic login for the “liveuser” account: - -``` -$ sed -i '/daemon/a AutomaticLoginEnable=true' /fc28/etc/gdm/custom.conf -$ sed -i '/daemon/a AutomaticLogin=liveuser' /fc28/etc/gdm/custom.conf -``` - -#### Like this: - -Like - -Loading... - --------------------------------------------------------------------------------- - -via: https://fedoramagazine.org/how-to-build-a-netboot-server-part-1/ - -作者：[Gregory Bartholomew][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://fedoramagazine.org/author/glb/ -[b]: https://github.com/lujun9972 -[1]: https://en.wikipedia.org/wiki/Network_booting -[2]: https://dl.fedoraproject.org/pub/fedora/linux/releases/28/Server/x86_64/iso/ -[3]: https://fedoramagazine.org/wp-content/uploads/2018/11/installation-summary-1024x768.png -[4]: https://docs.fedoraproject.org/en-US/Fedora/25/html/Networking_Guide/ch-Configure_Host_Names.html#sec_Understanding_Host_Names -[5]: https://en.wikipedia.org/wiki/Bridging_(networking) -[6]: https://www.centos.org/docs/5/html/5.1/Deployment_Guide/s3-nfs-server-config-exportfs-nfsv4.html -[7]: https://bugzilla.redhat.com/show_bug.cgi?id=1542567 -[8]: https://ipxe.org/ -[9]: https://en.wikipedia.org/wiki/EFI_system_partition -[10]: https://fedoramagazine.org/wp-content/uploads/2018/11/netboot-liveuser-1024x641.png diff --git a/sources/tech/20181123 Three SSH GUI Tools for Linux.md b/sources/tech/20181123 Three SSH GUI Tools for Linux.md new file mode 100644 index 0000000000..9691a737ca --- /dev/null +++ b/sources/tech/20181123 Three SSH GUI Tools for Linux.md @@ -0,0 +1,176 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Three SSH GUI Tools for Linux) +[#]: via: (https://www.linux.com/blog/learn/intro-to-linux/2018/11/three-ssh-guis-linux) +[#]: author: (Jack Wallen https://www.linux.com/users/jlwallen) +[#]: url: ( ) + +Three SSH GUI Tools for Linux +====== + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh.jpg?itok=3UcXhJt7) + +At some point in your career as a Linux administrator, you’re going to use Secure Shell (SSH) to remote into a Linux server or desktop. Chances are, you already have. In some instances, you’ll be SSH’ing into multiple Linux servers at once. In fact, Secure Shell might well be one of the most-used tools in your Linux toolbox. Because of this, you’ll want to make the experience as efficient as possible. For many admins, nothing is as efficient as the command line. However, there are users out there who do prefer a GUI tool, especially when working from a desktop machine to remote into and work on a server. + +If you happen to prefer a good GUI tool, you’ll be happy to know there are a couple of outstanding graphical tools for SSH on Linux. Couple that with a unique terminal window that allows you to remote into multiple machines from the same window, and you have everything you need to work efficiently. Let’s take a look at these three tools and find out if one (or more) of them is perfectly apt to meet your needs. + +I’ll be demonstrating these tools on [Elementary OS][1], but they are all available for most major distributions. + +### PuTTY + +Anyone that’s been around long enough knows about [PuTTY][2]. In fact, PuTTY is the de facto standard tool for connecting, via SSH, to Linux servers from the Windows environment. But PuTTY isn’t just for Windows. In fact, from withing the standard repositories, PuTTY can also be installed on Linux. PuTTY’s feature list includes: + + * Saved sessions. + + * Connect via IP address or hostname. + + * Define alternative SSH port. + + * Connection type definition. + + * Logging. + + * Options for keyboard, bell, appearance, connection, and more. + + * Local and remote tunnel configuration + + * Proxy support + + * X11 tunneling support + + + + +The PuTTY GUI is mostly a way to save SSH sessions, so it’s easier to manage all of those various Linux servers and desktops you need to constantly remote into and out of. Once you’ve connected, from PuTTY to the Linux server, you will have a terminal window in which to work. At this point, you may be asking yourself, why not just work from the terminal window? For some, the convenience of saving sessions does make PuTTY worth using. + +Installing PuTTY on Linux is simple. For example, you could issue the command on a Debian-based distribution: + +``` +sudo apt-get install -y putty +``` + +Once installed, you can either run the PuTTY GUI from your desktop menu or issue the command putty. In the PuTTY Configuration window (Figure 1), type the hostname or IP address in the HostName (or IP address) section, configure the port (if not the default 22), select SSH from the connection type, and click Open. + +![PuTTY Connection][4] + +Figure 1: The PuTTY Connection Configuration Window. + +[Used with permission][5] + +Once the connection is made, you’ll then be prompted for the user credentials on the remote server (Figure 2). + +![log in][7] + +Figure 2: Logging into a remote server with PuTTY. + +[Used with permission][5] + +To save a session (so you don’t have to always type the remote server information), fill out the IP address (or hostname), configure the port and connection type, and then (before you click Open), type a name for the connection in the top text area of the Saved Sessions section, and click Save. This will then save the configuration for the session. To then connect to a saved session, select it from the saved sessions window, click Load, and then click Open. You should then be prompted for the remote credentials on the remote server. + +### EasySSH + +Although [EasySSH][8] doesn’t offer the amount of configuration options found in PuTTY, it’s (as the name implies) incredibly easy to use. One of the best features of EasySSH is that it offers a tabbed interface, so you can have multiple SSH connections open and quickly switch between them. Other EasySSH features include: + + * Groups (so you can group tabs for an even more efficient experience). + + * Username/password save. + + * Appearance options. + + * Local and remote tunnel support. + + + + +Install EasySSH on a Linux desktop is simple, as the app can be installed via flatpak (which does mean you must have Flatpak installed on your system). Once flatpak is installed, add EasySSH with the commands: + +``` +sudo flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo + +sudo flatpak install flathub com.github.muriloventuroso.easyssh +``` + +Run EasySSH with the command: + +``` +flatpak run com.github.muriloventuroso.easyssh +``` + +The EasySSH app will open, where you can click the + button in the upper left corner. In the resulting window (Figure 3), configure your SSH connection as required. + +![Adding a connection][10] + +Figure 3: Adding a connection in EasySSH is simple. + +[Used with permission][5] + +Once you’ve added the connection, it will appear in the left navigation of the main window (Figure 4). + +![EasySSH][12] + +Figure 4: The EasySSH main window. + +[Used with permission][5] + +To connect to a remote server in EasySSH, select it from the left navigation and then click the Connect button (Figure 5). + +![Connecting][14] + +Figure 5: Connecting to a remote server with EasySSH. + +[Used with permission][5] + +The one caveat with EasySSH is that you must save the username and password in the connection configuration (otherwise the connection will fail). This means anyone with access to the desktop running EasySSH can remote into your servers without knowing the passwords. Because of this, you must always remember to lock your desktop screen any time you are away (and make sure to use a strong password). The last thing you want is to have a server vulnerable to unwanted logins. + +### Terminator + +Terminator is not actually an SSH GUI. Instead, Terminator functions as a single window that allows you to run multiple terminals (and even groups of terminals) at once. Effectively you can open Terminator, split the window vertical and horizontally (until you have all the terminals you want), and then connect to all of your remote Linux servers by way of the standard SSH command (Figure 6). + +![Terminator][16] + +Figure 6: Terminator split into three different windows, each connecting to a different Linux server. + +[Used with permission][5] + +To install Terminator, issue a command like: + +### sudo apt-get install -y terminator + +Once installed, open the tool either from your desktop menu or from the command terminator. With the window opened, you can right-click inside Terminator and select either Split Horizontally or Split Vertically. Continue splitting the terminal until you have exactly the number of terminals you need, and then start remoting into those servers. +The caveat to using Terminator is that it is not a standard SSH GUI tool, in that it won’t save your sessions or give you quick access to those servers. In other words, you will always have to manually log into your remote Linux servers. However, being able to see your remote Secure Shell sessions side by side does make administering multiple remote machines quite a bit easier. + +Few (But Worthwhile) Options + +There aren’t a lot of SSH GUI tools available for Linux. Why? Because most administrators prefer to simply open a terminal window and use the standard command-line tools to remotely access their servers. However, if you have a need for a GUI tool, you have two solid options and one terminal that makes logging into multiple machines slightly easier. Although there are only a few options for those looking for an SSH GUI tool, those that are available are certainly worth your time. Give one of these a try and see for yourself. + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/learn/intro-to-linux/2018/11/three-ssh-guis-linux + +作者：[Jack Wallen][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.linux.com/users/jlwallen +[b]: https://github.com/lujun9972 +[1]: https://elementary.io/ +[2]: https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html +[3]: https://www.linux.com/files/images/sshguis1jpg +[4]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh_guis_1.jpg?itok=DiNTz_wO (PuTTY Connection) +[5]: https://www.linux.com/licenses/category/used-permission +[6]: https://www.linux.com/files/images/sshguis2jpg +[7]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh_guis_2.jpg?itok=4ORsJlz3 (log in) +[8]: https://github.com/muriloventuroso/easyssh +[9]: https://www.linux.com/files/images/sshguis3jpg +[10]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh_guis_3.jpg?itok=bHC2zlda (Adding a connection) +[11]: https://www.linux.com/files/images/sshguis4jpg +[12]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh_guis_4.jpg?itok=hhJzhRIg (EasySSH) +[13]: https://www.linux.com/files/images/sshguis5jpg +[14]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh_guis_5.jpg?itok=piFEFYTQ (Connecting) +[15]: https://www.linux.com/files/images/sshguis6jpg +[16]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/ssh_guis_6.jpg?itok=-kYl6iSE (Terminator) diff --git a/sources/tech/20181124 14 Best ASCII Games for Linux That are Insanely Good.md b/sources/tech/20181124 14 Best ASCII Games for Linux That are Insanely Good.md new file mode 100644 index 0000000000..094467698b --- /dev/null +++ b/sources/tech/20181124 14 Best ASCII Games for Linux That are Insanely Good.md @@ -0,0 +1,335 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (14 Best ASCII Games for Linux That are Insanely Good) +[#]: via: (https://itsfoss.com/best-ascii-games/) +[#]: author: (Ankush Das https://itsfoss.com/author/ankush/) +[#]: url: ( ) + +14 Best ASCII Games for Linux That are Insanely Good +====== + +Text-based or should I say [terminal-based games][1] were very popular a decade back – when you didn’t have visual masterpieces like God Of War, Red Dead Redemption 2 or Spiderman. + +Of course, the Linux platform has its share of good games – but not always the “latest and greatest”. But, there are some ASCII games out there – to which you can never turn your back on. + +I’m not sure if you’d believe me, some of the ASCII games proved to be very addictive (So, it might take a while for me to resume work on the next article, or I might just get fired? – Help me!) + +Jokes apart, let us take a look at the best ASCII games. + +**Note:** Installing ASCII games could be time-consuming (some might ask you to install additional dependencies or simply won’t work). You might even encounter some ASCII games that require you build from Source. So, we’ve filtered out only the ones that are easy to install/run – without breaking a sweat. + +### Things to do before Running or Installing an ASCII Game + +Some of the ASCII games might require you to install [Simple DirectMedia Layer][2] unless you already have it installed. So, in case, you should install them first before trying to run any of the games mentioned in this article. + +For that, you just need to type in these commands: + +``` +sudo apt install libsdl2-2.0 +``` + +``` +sudo apt install libsdl2_mixer-2.0 +``` + + +### Best ASCII Games for Linux + +![Best Ascii games for Linux][3] + +The games listed are in no particular order of ranking. + +#### 1 . [Curse of War][4] + +![Curse of War ascii games][5] + +Curse of War is an interesting strategy game. You might find it a bit confusing at first but once you get to know it – you’ll love it. I’ll recommend you to take a look at the rules of the game on their [homepage][4] before launching the game. + +You will be building infrastructure, secure resources and directing your army to fight. All you have to do is place your flag in a good position to let your army take care of the rest. It’s not just about attacking – you need to manage and secure the resources to help win the fight. + +If you’ve never played any ASCII game before, be patient and spend some time learning it – to experience it to its fullest potential. + +##### How to install Curse of War? + +You will find it in the official repository. So, type in the following command to install it: + +``` +sudo apt install curseofwar +``` +#### 2. ASCII Sector + +![ascii sector][6] + +Hate strategy games? Fret not, ASCII sector is a game that has a space-setting and lets you explore a lot. + +Also, the game isn’t just limited to exploration, you need some action? You got that here as well. Of course, not the best combat experience- but it is fun. It gets even more exciting when you see a variety of bases, missions, and quests. You’ll encounter a leveling system in this tiny game where you have to earn enough money or trade in order upgrade your spaceship. + +The best part about this game is – you can create your own quests or play other’s. + +###### How to install ASCII Sector? + +You need to first download and unpack the archived package from the [official site][7]. After it’s done, open up your terminal and type these commands (replace the **Downloads** folder with your location where the unpacked folder exists, ignore it if the unpacked folder resides inside your home directory): + +``` +cd Downloads +cd asciisec +chmod +x asciisec +./asciisec +``` + +#### 3. DoomRL + +![doom ascii game][8] + +You must be knowing the classic game “Doom”. So, if you want the scaled down experience of it as a rogue-like, DoomRL is for you. It is an ASCII-based game, in case you don’t feel like it to be. + +It’s a very tiny game with a lot of gameplay hours to have fun with. + +###### How to install DoomRL? + +Similar to what you did for ASCII Sector, you need to download the official archive from their [download page][9] and then extract it to a folder. + +After extracting it, type in these commands: + +``` +cd Downloads // navigating to the location where the unpacked folder exists +``` + +``` +cd doomrl-linux-x64-0997 +chmod +x doomrl +./doomrl +``` +#### 4. Pyramid Builder + +![Pyramid Builder ascii game for Linux][10] + +Pyramid Builder is an innovative take as an ASCII game where get to improve your civilization by helping build pyramids. + +You need to direct the workers to farm, unload the cargo, and move the gigantic stones to successfully build the pyramid. + +It is indeed a beautiful ASCII game to download. + +###### How to install Pyramid Builder? + +Simply head to its official site and download the package to unpack it. After extraction, navigate to the folder and run the executable file. + +``` +cd Downloads +cd pyramid_builder_linux +chmod +x pyramid_builder_linux.x86_64 +./pyramid_builder_linux.x86_64 +``` +#### 5. DiabloRL + +![Diablo ascii RPG game][11] + +If you’re an avid gamer, you must have heard about Blizzard’s Diablo 1. It is undoubtedly a good game. + +You get the chance to play a unique rendition of the game – which is an ASCII game. DiabloRL is a turn-based rogue-like game that is insanely good. You get to choose from a variety of classes (Warrior, Sorcerer, or Rogue). Every class would result in a different gameplay experience with a set of different stats. + +Of course, personal preference will differ – but it’s a decent “unmake” of Diablo. What do you think? + +#### 6. Ninvaders + +![Ninvaders terminal game for Linux][12] + +Ninvaders is one of the best ASCII game just because it’s so simple and an arcade game to kill time. + +You have to defend against a hord of invaders – just finish them off before they get to you. It sounds very simple – but it is a challenging game. + +##### How to install Ninvaders? + +Similar to Curse of War, you can find this in the official repository. So, just type in this command to install it: + +``` +sudo apt install ninvaders  +``` +#### 7. Empire + +![Empire terminal game][13] + +A real-time strategy game for which you will need an active Internet connection. I’m personally not a fan of Real-Time strategy games, but if you are a fan of such games – you should really check out their [guide][14] to play this game – because it can be very challenging to learn. + +The rectangle contains cities, land, and water. You need to expand your city with an army, ships, planes and other resources. By expanding quickly, you will be able to capture other cities by destroying them before they make a move. + +##### How to install Empire? + +Install this is very simple, just type in the following command: + +``` +sudo apt install empire +``` + +#### 8. Nudoku + +![Nudoku is a terminal version game of Sudoku][15] + +Love Sudoku? Well, you have Nudoku – a clone for it. A perfect time-killing ASCII game while you relax. + +It presents you with three difficulty levels – Easy, normal, and hard. If you want to put up a challenge with the computer, the hard difficulty will be perfect! If you just want to chill, go for the easy one. + +##### How to install Nudoku? + +It’s very easy to get it installed, just type in the following command in the terminal: + +``` +sudo apt install nudoku +``` + +#### 9\. Nethack + +A dungeons and dragon-style ASCII game which is one of the best out there. I believe it’s one of your favorites if you already knew about ASCII games for Linux – in general. + +It features a lot of different levels (about 45) and comes packed in with a bunch of weapons, scrolls, potions, armor, rings, and gems. You can also choose permadeath as your mode to play it. + +It’s not just about killing here – you got a lot to explore. + +##### How to install Nethack? + +Simply follow the command below to install it: + +``` +sudo apt install nethack +``` + +#### 10. ASCII Jump + +![ascii jump game][16] + +ASCII Jump is a dead simple game where you have to slide along a varierty of tracks – while jumping, changing position, and moving as long as you can to cover maximum distance. + +It’s really amazing to see how this ASCII game looks like (visually) even it seems so simple. You can start with the training mode and then proceed to the world cup. You also get to choose your competitors and the hills on which you want to start the game. + +##### How to install Ascii Jump? + +To install the game, just type the following command: + +``` +sudo apt install asciijump +``` + +#### 11. Bastet + +![Bastet is tetris game in ascii form][17] + +Let’s just not pay any attention to the name – it’s actually a fun clone of Tetris game. + +You shouldn’t expect it to be just another ordinary tetris game – but it will present you the worst possible bricks to play with. Have fun! + +##### How to install Bastet? + +Open the terminal and type in the following command: + +``` +sudo apt install bastet +``` + +#### 12\. Bombardier + +![Bomabrdier game in ascii form][18] + +Bombardier is yet another simple ASCII game which will keep you hooked on to it. + +Here, you have a helicopter (or whatever you’d like to call your aircraft) which lowers down every cycle and you need to throw bombs in order to destroy the blocks/buildings under you. The game also puts a pinch of humor for the messages it displays when you destroy a block. It is fun. + +##### How to install Bombardier? + +Bombardier is available in the official repository, so just type in the following in the terminal to install it: + +``` +sudo apt install bombardier +``` + +#### 13\. Angband + +![Angband ascii game][19] + +A cool dungeon exploration game with a neat interface. You can see all the vital information in a single screen while you explore the game. + +It contains different kinds of race to pick a character. You can either be an Elf, Hobbit, Dwarf or something else – there’s nearly a dozen to choose from. Remember, that you need to defeat the lord of darkness at the end – so make every upgrade possible to your weapon and get ready. + +How to install Angband? + +Simply type in the following command: + +``` +sudo apt install angband +``` + +#### 14\. GNU Chess + +![GNU Chess is a chess game that you can play in Linux terminal][20] + +How can you not play chess? It is my favorite strategy game! + +But, GNU Chess can be tough to play with unless you know the Algebraic notation to describe the next move. Of course, being an ASCII game – it isn’t quite possible to interact – so it asks you the notation to detect your move and displays the output (while it waits for the computer to think its next move). + +##### How to install GNU Chess? + +If you’re aware of the algebraic notations of Chess, enter the following command to install it from the terminal: + +``` +sudo apt install gnuchess +``` + +#### Some Honorable Mentions + +As I mentioned earlier, we’ve tried to recommend you the best (but also the ones that are the easiest to install on your Linux machine). + +However, there are some iconic ASCII games which deserve the attention and requires a tad more effort to install (You will get the source code and you need to build it / install it). + +Some of those games are: + ++ [Cataclysm: Dark Days Ahead][22] ++ [Brogue][23] ++ [Dwarf Fortress][24] + +You should follow our [guide to install software from source code][21]. + +### Wrapping Up + +Which of the ASCII games mentioned seem perfect for you? Did we miss any of your favorites? + +Let us know your thoughts in the comments below. + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/best-ascii-games/ + +作者：[Ankush Das][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/ankush/ +[b]: https://github.com/lujun9972 +[1]: https://itsfoss.com/best-command-line-games-linux/ +[2]: https://www.libsdl.org/ +[3]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/best-ascii-games-featured.png?resize=800%2C450&ssl=1 +[4]: http://a-nikolaev.github.io/curseofwar/ +[5]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/11/curseofwar-ascii-game.jpg?fit=800%2C479&ssl=1 +[6]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/ascii-sector-game.jpg?fit=800%2C424&ssl=1 +[7]: http://www.asciisector.net/download/ +[8]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/doom-rl-ascii-game.jpg?ssl=1 +[9]: https://drl.chaosforge.org/downloads +[10]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/pyramid-builder-ascii-game.jpg?fit=800%2C509&ssl=1 +[11]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/diablo-rl-ascii-game.jpg?ssl=1 +[12]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/ninvaders-ascii-game.jpg?fit=800%2C426&ssl=1 +[13]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/empire-ascii-game.jpg?fit=800%2C570&ssl=1 +[14]: http://www.wolfpackempire.com/infopages/Guide.html +[15]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/11/nudoku-ascii-game.jpg?fit=800%2C434&ssl=1 +[16]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/11/ascii-jump.jpg?fit=800%2C566&ssl=1 +[17]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/bastet-tetris-clone-ascii.jpg?fit=800%2C465&ssl=1 +[18]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/11/bombardier.jpg?fit=800%2C571&ssl=1 +[19]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/angband-ascii-game.jpg?ssl=1 +[20]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/gnuchess-ascii-game.jpg?ssl=1 +[21]: https://itsfoss.com/install-software-from-source-code/ +[22]: https://github.com/CleverRaven/Cataclysm-DDA +[23]: https://sites.google.com/site/broguegame/ +[24]: http://www.bay12games.com/dwarves/index.html + diff --git a/sources/tech/20181127 Bio-Linux- A stable, portable scientific research Linux distribution.md b/sources/tech/20181127 Bio-Linux- A stable, portable scientific research Linux distribution.md new file mode 100644 index 0000000000..a38acec9da --- /dev/null +++ b/sources/tech/20181127 Bio-Linux- A stable, portable scientific research Linux distribution.md @@ -0,0 +1,79 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Bio-Linux: A stable, portable scientific research Linux distribution) +[#]: via: (https://opensource.com/article/18/11/bio-linux) +[#]: author: (Matt Calverley https://opensource.com/users/mattcalverley) +[#]: url: ( ) + +Bio-Linux: A stable, portable scientific research Linux distribution +====== +Linux distro's integrated software approach offers powerful bioinformatic data analysis with a familiar look and feel. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/LIFE_science.png?itok=WDKARWGV) + +Bio-Linux was introduced and detailed in a [Nature Biotechnology paper in July 2006][1]. The distribution was a group effort by the Natural Environment Research Council in the UK. As the creators and authors point out, the analysis demands of high-throughput “-omic” (genomic, proteomic, metabolomic) science has necessitated the development of integrated computing solutions to analyze the resultant mountains of experimental data. + +From this need, Bio-Linux was born. The distribution, [according to its creators][2], serves as a “free bioinformatics workstation platform that can be installed on anything from a laptop to a large server.” The current distro version, Bio-Linux 8, is built on an Ubuntu 14.04 LTS base. Thus, the general look and feel of Bio-Linux is similar to that of Ubuntu. + +In my own work as a research immunologist, I can attest to both the need for and success of the integrated software approach in Bio-Linux's design and development. Bio-Linux functions as a true turnkey solution to data pipeline requirements of modern science. As the website mentions, Bio-Linux includes [more than 250 pre-installed software packages][3], many of which are specific to the requirements of bioinformatic data analysis. + +The power of this approach becomes immediately evident when you try to duplicate the software installation process under another operating system. Integrating all software components and installing all required dependencies is immensely time-consuming, and in some instances is not even possible outside of the Linux operating system. The Bio-Linux distro provides a portable, stable, integrated environment with pre-installed software sufficient to begin a vast array of bioinformatic analysis tasks. + +By now you’re probably saying, “I’m sold—how do I get this amazing distro?” + +I’m glad you asked. I'll start by saying that there is excellent documentation on the Bio-Linux website. This [documentation][4] covers both installation instructions and a very thorough overview of using the distro. + +The distro can be installed and run locally, run off a CD/DVD or USB, installed on a server, or run out of a virtual machine environment. To begin the installation process for local installation, [download the disk image or ISO][5] for the Bio-Linux distro. The disk image is a 3.3GB file, and depending on your internet download speed, this may be a good time to get a cup of coffee or take a nice nap. + +Once the ISO has been downloaded, the Bio-Linux developers recommend using [UNetBootin][6], a freely available cross-platform software package used to make bootable USBs. There is a link provided for UNetBootin on the Bio-Linux website. I can attest to the effectiveness of UNetBootin in both Mac and Linux operating systems. + +On Unix family operating systems (Mac OS and Linux), it is also possible to make a bootable USB from the command line using the `dd `command: + +``` +sudo umount “USB location” + +sudo dd bs=4M if=”ISO location” of =”USB location” conv=fdatasync +``` +Regardless of the method you use, this might be another good time for a coffee break. + +At this point in my installation, UNetBootin appeared to freeze at the `squashfs` file transfer during bootable USB creation. However, a quick check of the Ubuntu disks application confirmed that the file was still being written to the USB. In other words, be patient—it takes quite some time to make the bootable USB. + +Once you’ve had your coffee and you have a finished USB in hand, you are ready to use Bio-Linux. As the Bio-Linux website points out, if you are trying to use a bootable USB with a Mac computer (particularly newer hardware versions), you may not be able to boot from the USB. There are workarounds, but they involve configuring the system for dual boot. Likewise, on Windows-based machines, it may be necessary to make changes to the boot order and possibly the secure boot settings for the machine from within BIOS. + +From this point, how you use the distro is up to you. You can run the distro from the USB to test it. You can install the distro to your computer. You can even follow the instructions on the Bio-Linux website to make a VM instance of the distro or run it on a server. Regardless of how you use it, you have a high-powered bioinformatic data analysis workstation at your disposal. + +Maybe you have a professional need for such a workstation, but even if you never use Bio-Linux as a professional researcher, it could provide a great resource for biology teaching professionals at all levels to introduce students to modern bioinformatics principles. For the price of a laptop and a USB, every school can have an in silico teaching resource to complement classroom lessons in the “-omics” age. Your only limitations are your creativity and the performance of your hardware. + +### More on Linux + +As an open source operating system with strong community support, the Linux kernel shares many of the strengths common to other successful open source software endeavors. Linux tends to be both stable and amenable to customization. It is also fairly hardware-agnostic, capable of running alongside other operating systems on a wide array of hardware configurations. In fact, installing Linux is a common method of regaining usability from dated hardware that is incapable of running other modern operating systems. Linux is also highly portable and can be run from any bootable external storage device, such as a USB drive, without the need to permanently install the operating system. + +It is this combination of stability, customizability, and portability that initially drew me to Linux. Each Linux operating system variant is referred to as a distribution (or distro), and it seems as though there is a Linux distribution for every imaginable computing scenario or desire. The options can actually be rather intimidating, and I suspect they may often discourage people from trying Linux. + +“How many different distributions can there possibly be?” you might wonder. If you have a few minutes, or even a few hours, have a look at [DistroWatch.com][7]. As its name implies, this site is devoted to the cataloging of all things Linux distribution-related. For visual learners, there is an amazing [Linux family tree][8] that really puts it into perspective. + +While [entire books][9] are devoted to the topic of Linux distributions, the differences often depend on what software is included in the base installation, how the software is managed, and graphical differences affecting the “look and feel” of the distribution. Certainly, there are also subtleties of hardware compatibility, speed, and stability. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/11/bio-linux + +作者：[Matt Calverley][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/mattcalverley +[b]: https://github.com/lujun9972 +[1]: https://www.nature.com/articles/nbt0706-801 +[2]: http://environmentalomics.org/bio-linux/ +[3]: http://environmentalomics.org/bio-linux-software-list/ +[4]: http://nebc.nerc.ac.uk/downloads/courses/Bio-Linux/bl8_latest.pdf +[5]: http://environmentalomics.org/bio-linux-download/ +[6]: https://unetbootin.github.io/ +[7]: https://distrowatch.com/ +[8]: https://distrowatch.com/images/other/distro-family-tree.png +[9]: https://www.amazon.com/Introducing-Linux-Distros-Dieguez-Castro/dp/1484213939 diff --git a/sources/tech/20181128 Arch-Audit - A Tool To Check Vulnerable Packages In Arch Linux.md b/sources/tech/20181128 Arch-Audit - A Tool To Check Vulnerable Packages In Arch Linux.md new file mode 100644 index 0000000000..d359a4f57c --- /dev/null +++ b/sources/tech/20181128 Arch-Audit - A Tool To Check Vulnerable Packages In Arch Linux.md @@ -0,0 +1,128 @@ +[#]: collector: (lujun9972) +[#]: translator: ( Auk7F7) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Arch-Audit : A Tool To Check Vulnerable Packages In Arch Linux) +[#]: via: (https://www.2daygeek.com/arch-audit-a-tool-to-check-vulnerable-packages-in-arch-linux/) +[#]: author: (Prakash Subramanian https://www.2daygeek.com/author/prakash/) +[#]: url: ( ) + + +Arch-Audit : A Tool To Check Vulnerable Packages In Arch Linux +====== + +We have to make the system up-to date to minimize the downtime and issues. + +It’s one of the routine task for Linux administrator to patch the system once in a month or 60 days once or 90 days at maximum. + +It would be sufficient schedule and we can’t do it this less than a month as it’s involve multiple activities and environments. + +Basically infrastructure comes with Test, Development, QA a.k.a Staging & Prod environments. + +Initially we will deploy the patches in the Test environment and corresponding team will be monitoring the system a week then they will give a status report like good or bad. + +If it’s success then we will move forward to other environments. If everything is good then finally we will patch production servers. + +Many of the organization has prepare to patch entire system. i mean full system update. It is a general patching schedule for a typical infrastructure. + +In some of the infrastructure they may have only production environment so, we should not prepare for the full system update instead we can go with security patch to make the system more stable and secure. + +Since Arch Linux and its derivatives distributions are fall under rolling release can be considered to be always up-to-date, as it uses the latest versions of software packages from the upstream. + +In some cases if you want to update security patch alone then you have to use arch-audit tool to identify and fix the security patches. + +### What is a Vulnerability? + +A vulnerability is a security weakness in a software program or hardware components (firmware). It’s a flaw that can leave it open to attack. + +To mitigate this we need to patch accordingly like for application/hardware it could be a code changes or config changes or parameter changes. + +### What is Arch-Audit Tool? + +[Arch-audit][1] is a tool like pkg-audit for Arch Linux system. It Uses data collected by the awesome Arch Security Team. It wont scan and find the vulnerable packages on your system like **yum –security check-update & yum updateinfo list available** and it will simply parse the page and display the results in terminal. So, it would show the accurate data. + +The Arch Security Team is a group of volunteers whose goal is to track security issues with Arch Linux packages. All issues are tracked on the Arch Linux security tracker. + +The team was formerly known as the Arch CVE Monitoring Team. The mission of the Arch Security Team is to contribute to the improvement of the security of Arch Linux. + +### How to Install arch-audit tool in Arch Linux + +The arch-audit tool is available in community repository so you can use the Pacman Package Manager to install it. + +``` +$ sudo pacman -S arch-audit +``` + +Run the `arch-audit` tool to find the open vulnerable packages on Arch based distributions. + +``` +$ arch-audit +Package cairo is affected by CVE-2017-7475. Low risk! +Package exiv2 is affected by CVE-2017-11592, CVE-2017-11591, CVE-2017-11553, CVE-2017-17725, CVE-2017-17724, CVE-2017-17723, CVE-2017-17722. Medium risk! +Package libtiff is affected by CVE-2018-18661, CVE-2018-18557, CVE-2017-9935, CVE-2017-11613. High risk!. Update to 4.0.10-1! +Package openssl is affected by CVE-2018-0735, CVE-2018-0734. Low risk! +Package openssl-1.0 is affected by CVE-2018-5407, CVE-2018-0734. Low risk! +Package patch is affected by CVE-2018-6952, CVE-2018-1000156. High risk!. Update to 2.7.6-7! +Package pcre is affected by CVE-2017-11164. Low risk! +Package systemd is affected by CVE-2018-6954, CVE-2018-15688, CVE-2018-15687, CVE-2018-15686. Critical risk!. Update to 239.300-1! +Package unzip is affected by CVE-2018-1000035. Medium risk! +Package webkit2gtk is affected by CVE-2018-4372. Critical risk!. Update to 2.22.4-1! +``` + +The above result shows the vulnerability risk status as well such as Low, Medium and Critical. + +To Show only vulnerable package names and their versions. + +``` +$ arch-audit -q +cairo +exiv2 +libtiff>=4.0.10-1 +openssl +openssl-1.0 +patch>=2.7.6-7 +pcre +systemd>=239.300-1 +unzip +webkit2gtk>=2.22.4-1 +``` + +To show only packages that have already been fixed. + +``` +$ arch-audit --upgradable --quiet +libtiff>=4.0.10-1 +patch>=2.7.6-7 +systemd>=239.300-1 +webkit2gtk>=2.22.4-1 +``` + +To cross check the above results, i’m going to test one of the package which is listed above in to confirm whether the vulnerability is still open or fixed it. Yes, it’s fixed and published the updated package in repository on yesterday. +![][3] + +To print only package names and associated CVEs alone. + +``` +$ arch-audit -uf "%n|%c" +libtiff|CVE-2018-18661,CVE-2018-18557,CVE-2017-9935,CVE-2017-11613 +patch|CVE-2018-6952,CVE-2018-1000156 +systemd|CVE-2018-6954,CVE-2018-15688,CVE-2018-15687,CVE-2018-15686 +webkit2gtk|CVE-2018-4372 +``` + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/arch-audit-a-tool-to-check-vulnerable-packages-in-arch-linux/ + +作者：[Prakash Subramanian][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/prakash/ +[b]: https://github.com/lujun9972 +[1]: https://github.com/ilpianista/arch-audit +[2]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[3]: https://www.2daygeek.com/wp-content/uploads/2018/11/A-Tool-To-Check-Vulnerable-Packages-In-Arch-Linux.png diff --git a/sources/tech/20181128 Building custom documentation workflows with Sphinx.md b/sources/tech/20181128 Building custom documentation workflows with Sphinx.md new file mode 100644 index 0000000000..7d9137fa40 --- /dev/null +++ b/sources/tech/20181128 Building custom documentation workflows with Sphinx.md @@ -0,0 +1,126 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Building custom documentation workflows with Sphinx) +[#]: via: (https://opensource.com/article/18/11/building-custom-workflows-sphinx) +[#]: author: ([Mark Meyer](https://opensource.com/users/ofosos)) +[#]: url: ( ) + +Building custom documentation workflows with Sphinx +====== +Create documentation the way that works best for you. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/programming-code-keyboard-laptop.png?itok=pGfEfu2S) + +[Sphinx][1] is a popular application for creating documentation, similar to JavaDoc or Jekyll. However, Sphinx's reStructured Text input allows for a higher degree of customization than those other tools. + +This tutorial will explain how to customize Sphinx to suit your workflow. You can follow along using sample code on [GitHub][2]. + +### Some definitions + +Sphinx goes far beyond just enabling you to style text with predefined tags. It allows you to shape and automate your documentation by defining new roles and directives. A role is a single word element that usually is rendered inline in your documentation, while a directive can contain more complex content. These can be contained in a domain. + +A Sphinx domain is a collection of directives and roles as well as a few other things, such as an index definition. Your next Sphinx domain could be a specific programming language (Sphinx was developed to create Python's documentation). Or you might have a command line tool that implements the same command pattern (e.g., **tool \--args**) over and over. You can document it with a custom domain, adding directives and indexes along the way. + +Here's an example from our **recipe** domain: + +``` +The recipe contains `tomato` and `cilantro`. + +.. rcp:recipe:: TomatoSoup +  :contains: tomato cilantro salt pepper   + +  This recipe is a tasty tomato soup, combine all ingredients +  and cook. +``` + +Now that we've defined the recipe **TomatoSoup** , we can reference it anywhere in our documentation using the custom role **refef**. For example: + +``` +You can use the :rcp:reref:`TomatoSoup` recipe to feed your family. +``` + +This enables our recipes to show up in two indices: the first lists all recipes, and the second lists all recipes by ingredient. + +### What's in a domain? + +A Sphinx domain is a specialized container that ties together roles, directives, and indices, among other things. The domain has a name ( **rcp** ) to address its components in the documentation source. It announces its existence to Sphinx in the **setup()** method of the package. From there, Sphinx can find roles and directives, since these are part of the domain. + +This domain also serves as the central catalog of objects in this sample. Using initial data, it defines two variables, **objects** and **obj2ingredient**. These contain a list of all objects defined (all recipes) and a hash that maps a canonical ingredient name to the list of objects. + +``` +initial_data = { +    'objects': [],  # object list +    'obj2ingredient': {},  # ingredient -> [objects] +} +``` + +The way we name objects is common across our extension. For each object created, the canonical name is **rcp. .**, where **< typename>** is the Python type of the object, and **< objectname>** is the name the documentation writer gives the object. This enables the extension to use different object types that share the same name. + +Having a canonical name and central place for our objects is a huge advantage. Both our indices and our cross-referencing code use this feature. + +### Custom roles and directives + +In our example, **.. rcp:recipe::** indicates a custom directive. You might think it's overly specific to create custom syntax for these items, but it illustrates the degree of customization you can get in Sphinx. This provides rich markup that structures documents and leads to better docs. Specialization allows us to extract information from our docs. + +Our definition for this directive will provide minimal formatting, but it will be functional. + +``` +class RecipeNode(ObjectDescription): +  """A custom node that describes a recipe.""" + +  required_arguments = 1 + +  option_spec = { +    'contains': rst.directives.unchanged_required +  } +``` + +For this directive, **required_arguments** tells Sphinx to expect one parameter, the recipe name. **option_spec** lists the optional arguments, including their names. Finally, **has_content** specifies that there will be more reStructured Text as a child to this node. + +We also implement multiple methods: + + * **handle_signature()** implements parsing the signature of the directive and passes on the object's name and type to its superclass + * **add_taget_and_index()** adds a target (to link to) and an entry to the index for this node + + + +### Creating indices + +Both **IngredientIndex** and **RecipeIndex** are derived from Sphinx's **Index** class. They implement custom logic to generate a tuple of values that define the index. Note that **RecipeIndex** is a degenerate index that has only one entry. Extending it to cover more object types—and moving from a **RecipeDomain** to a **CookbookDomain** —is not yet part of the code. + +Both indices use the method **generate()** to do their work. This method combines the information from our domain, sorts it, and returns it in a list structure that will be accepted by Sphinx. See the [Sphinx Domain API][3] page for more information. + +The first time you visit the Domain API page, you may be a little overwhelmed by the structure. But our ingredient index is just a list of tuples, like **('tomato', 'TomatoSoup', 'test', 'rec-TomatoSoup',...)**. + +### Referencing recipes + +Adding cross-references is not difficult (but it's also not a given). Add an **XRefRole** to the domain and implement the method **resolve_xref()**. Having a custom role to reference a type allows us to unambiguously reference any object, even if two objects have the same name. If you look at the parameters of **resolve_xref()** in **Domain** , you'll see **typ** and **target**. These define the cross-reference type and its target name. We'll use **target** to resolve our destination from our domain's **objects** because we currently have only one type of node. + +We can add the cross-reference role to **RecipeDomain** in the following way: + +``` +roles = { +    'reref': XRefRole() +} +``` + +There's nothing for us to implement. Defining a working **resolve_xref()** and attaching an **XRefRole** to the domain is all you need to do. + + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/11/building-custom-workflows-sphinx + +作者：[Mark Meyer][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/ofosos +[b]: https://github.com/lujun9972 +[1]: http://www.sphinx-doc.org/en/master/ +[2]: https://github.com/ofosos/sphinxrecipes +[3]: https://www.sphinx-doc.org/en/master/extdev/domainapi.html#sphinx.domains.Index.generate diff --git a/sources/tech/20181128 How to test your network with PerfSONAR.md b/sources/tech/20181128 How to test your network with PerfSONAR.md new file mode 100644 index 0000000000..9e9e66ef62 --- /dev/null +++ b/sources/tech/20181128 How to test your network with PerfSONAR.md @@ -0,0 +1,148 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (How to test your network with PerfSONAR) +[#]: via: (https://opensource.com/article/18/11/how-test-your-network-perfsonar) +[#]: author: (Jessica Repka https://opensource.com/users/jrepka) +[#]: url: ( ) + +How to test your network with PerfSONAR +====== +Set up a single-node configuration to measure your network performance. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/command_line_prompt.png?itok=wbGiJ_yg) + +[PerfSONAR][1] is a network measurement toolkit collection for testing and sharing data on end-to-end network perfomance. + +The overall benefit of using network measurement tools like PerfSONAR is they can find issues before they become a large elephant in the room that nobody wants to talk about. Specifically, with the right answers from the right tools, patching can become more stringent, network traffic can be shaped to speed connections across the board, and the network infrastructure design can be improved. + +PerfSONAR is licensed under the open source Apache 2.0 license, which makes it more affordable than most tools that do this type of analysis, a key advantage given constrained network infrastructure budgets. + +### PerfSONAR versions + +Several versions of PerfSONAR are available: + + * **Perfsonar-tools:** The command line client version meant for on-demand testing. + * **Perfsonar-testpoint:** Adds automated testing and central management testing to PerfSONAR-tools. It has an archiving feature, but the archive must be set to an external node. + * **Perfsonar-core:** Includes everything in the testpoint software, but with local rather than external archiving. + * **Perfsonar-toolkit:** The core software; it includes a web UI with systemwide security settings. + * **Perfsonar-centralmanagement:** A completely separate version of PerfSONAR that uses mass grids of nodes to display results. It also has a feature to push out task templates to every node that is sending measurements back to the central host. + + + +This tutorial will use **PerfSonar-toolkit** ; the tools used in this software include [iPerf, iPerf3][2], and [OWAMP][3]. + +### Requirements + + * **Recommended operating system:** CentOS/RHEL7 + * **ISO:** [Downloading][4] the full installation ISO is the fastest way to get the software up and running. While there is a [Debian version][5], it is much harder and more complicated to use. + * **Minimum hardware requirements:** 2 cores and 4GB RAM + * **Recommended hardware:** 200GB HDD, 4 cores, 6GB of RAM + + + +### Installing and configuring PerfSONAR + +The installation is a quick CentOS install where you pick your timezone and configuration for the hard drive and user. I suggest using hard drive autoconfiguration, as you only need to choose "Install Toolkit" and follow the prompts from there. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image1_welcome.png) +Select your language. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image4_language.png) +Select a destination. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image3_destination.png) +After base installation, you see the Linux login screen. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image5a_linuxlogin.png) +After you log in, you are prompted to create a user ID and password to log into PerfSONAR's web frontend—make sure to remember your login information. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image5_createuser.png) +You're also asked to disable SSH access for root and create a new user for sudo; just follow the steps to create the new user. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image17_sudouser.png) +You can use a provisioning service to automatically provide an IP address and hostname. Otherwise, you will have to set the hostname (optional) and configure the IP address. + +### Log into the web frontend + +Once the base configuration is complete, you can log into the web frontend via **** or ****. The web frontend will appear with the name or IP address of the device you just set up, the list of tools used, a test result area, host information, global node directory, and on-demand testing. + +These options appear on the right-hand side of the web page. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image13_ondemandtesting.png) +![](https://opensource.com/sites/default/files/uploads/perfsonar_image1_frontend.png) + +For a single configuration mode, you will need another node to test with. To get one, click on the global node [Lookup Service Directory][6] link, which will bring you to a list of available nodes. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image20_lookupservicemap1.png) + +Pick an external node from the pScheduler Server list on the left. (I picked ESnet's Atlanta testing server.) +![](https://opensource.com/sites/default/files/uploads/perfsonar_image10_selectnode.png) + +Configure the node by clicking the Log In button and entering the user ID and password you created during base configuration. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image8_login.png) + +Next, choose Configuration. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image14_chooseconfig.png) + +This takes you to the configuration page, where you can add tests to other nodes by clicking Test, then clicking +Test. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image6_config.png) + +After you click +Test, you'll see a pop-up window with some drop-down options. For this tutorial, I used One-Way Active Measurement Protocol (OWAMP) testing for one-way latency against the ESnet Atlanta node that is IPv4. + +#### Side bar + + * The OWAMP measures unidirectional characteristics such as one-way delay and one-way loss. High-precision measurement of these one-way IP performance metrics became possible with wider availability of good time sources (such as GPS and CDMA). OWAMP enables the interoperability of these measurements. + * IPv4 is a fourth version of the Internet Protocol, which today is the main protocol to most of the internet. IPv4 protocol defines the rules for the operation of computer networks on the packet-exchange principle. This is a low-level protocol that is responsible for the connection between the nodes of the network on the basis of IP Addresses. + * The IPv4 node is a perfsonar testing node that only does network testing using the IPv4 protocols. The perfsonar testing node you connect to is the same application that is built in this documentation. + + + +The drop-down should use the server's main interface. Confirm that the test is enabled (the Test Status switch will be green) and click the OK button at the bottom of the window. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image9_addtest.png) + +Once you have added the test information, click the Save button at the bottom of the page. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image18_savetestinfo.png) + +You will see information about all of the scheduled tests and the hosts they are testing. You can add more hosts to the test by clicking the Settings icon in the Actions column. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image16_scheduledtests.png) + +The testing intervals are automatically set according to the recommended settings. If the test frequency increases, the tests will still run OK, but your hard drive may fill up with data more quickly. + +Once the test finishes, click View Public Dashboard to see the data that's returned. Note that it may take anywhere from five minutes to several hours to access the first sets of data. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image19_viewpublicdash.png) + +The public dashboard shows a high-level summary dataset. If you want more information, click Details. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image2_details.png) + +You'll see a larger graph and have the option to expand the graph over a year as data is collected. +![](https://opensource.com/sites/default/files/uploads/perfsonar_image7_expandedgraph.png) + +PerfSONAR is now up, running, and testing the network. You can also test with two nodes inside your network (or one internal network node and one external node). + +### What can you learn about your network? + +In the time I've been using PerfSONAR, I've already uncovered the following issues: + + * Asymmetrical throughput + * Fiber outages + * Speed on circuit not meeting contractual agreement + * Internal network slowdowns due to misconfigurations + * Incorrect routes + + + +Have you used PerfSONAR or a similar tool? What benefits have you seen? + + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/11/how-test-your-network-perfsonar + +作者：[Jessica Repka][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jrepka +[b]: https://github.com/lujun9972 +[1]: https://www.perfsonar.net/ +[2]: https://iperf.fr/ +[3]: http://software.internet2.edu/owamp/ +[4]: http://downloads.perfsonar.net/toolkit/pS-Toolkit-4.1.3-CentOS7-FullInstall-x86_64-2018Oct24.iso +[5]: http://docs.perfsonar.net/install_options.html# +[6]: http://stats.es.net/ServicesDirectory/ diff --git a/sources/tech/20181128 Turn an old Linux desktop into a home media center.md b/sources/tech/20181128 Turn an old Linux desktop into a home media center.md new file mode 100644 index 0000000000..f87750b513 --- /dev/null +++ b/sources/tech/20181128 Turn an old Linux desktop into a home media center.md @@ -0,0 +1,87 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (Turn an old Linux desktop into a home media center) +[#]: via: (https://opensource.com/article/18/11/old-linux-desktop-new-home-media-center) +[#]: author: ([Alan Formy-Duval](https://opensource.com/users/alanfdoss)) +[#]: url: ( ) + +Turn an old Linux desktop into a home media center +====== +Repurpose an outdated computer to browse the internet and watch videos on your big screen TV. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/migration_innovation_computer_software.png?itok=VCFLtd0q) + +My first attempt to set up an "entertainment PC" was back in the late 1990s, using a plain old desktop computer with a Trident ProVidia 9685 PCI graphics card. I used what was known as a "TV-out" card, which had an extra output to connect to a standard television set. The onscreen result didn't look very nice and there was no audio output. And it was ugly: I had an S-Video cable running across my living room floor to my 19" Sony Trinitron CRT TV set. + +I had the same sad result from Linux and Windows 98. After struggling with systems that never looked right, I gave up for a few years. Thankfully, today we have HDMI with its vastly better performance and standardized resolution, which makes an inexpensive home media center a reality. + +My new media center entertainment computer is actually my old Ubuntu Linux desktop, which I recently replaced with something faster. The computer became too slow for work, but its AMD Phenom II X4 965 processor at 3.4GHz and 8GB of RAM are good enough for general browsing and video streaming. + +Here are the steps I took to get the best possible performance out of this old system for its new role. + +### Hardware + +First, I removed unnecessary devices including a card reader, hard drives, DVD drive, and a rear-mounted USB card, and I added a PCI-Express WiFi card. I installed Ubuntu to a single solid-state drive (SSD), which can really improve the performance of any older system. + +### BIOS + +In the BIOS, I disabled all unused devices, such as floppy and IDE drive controllers. I disabled onboard video because I installed an NVidia GeForce GTX 650 PCI Express graphics card with an HDMI output. I also disabled onboard audio because the NVidia graphics card chipset provides audio. + +### Audio + +The Nvidia GeForce GTX audio device is listed in the GNOME Control Center's sound settings as a GK107 HDMI Audio Controller, so a single HDMI cable handles both audio and video. There's no need for an audio cable connected to the onboard audio output jack. + +![Sound settings screenshot][2] + +HDMI audio controller shown in GNOME sound settings. + +### Keyboard and mouse + +I have a wireless keyboard and mouse, both from Logitech. When I installed them, I plugged in both peripherals' USB receivers; they worked, but I often had signal-response problems. Then I discovered one was labeled a Unifying Receiver, which meant it can handle multiple Logitech input devices on its own. Logitech doesn't provide software to configure Unifying Receivers in Linux; fortunately, the open source utility [Solaar][3] does. Using a single receiver solved my input performance issues. + +![Solaar][5] + +Solaar Unifying Receiver interface. + +### Video + +It was initially hard to read fonts on my 47" flat-panel TV, so I enabled "Large Text" under Universal Access. I downloaded some wallpapers matching the TV's 1920x1080 resolution that look fantastic! + +### Final touches + +I needed to balance the computer's cooling needs with my desire for unimpeded entertainment. Since this is a standard ATX mini-tower computer, I made sure I had just enough fans with carefully configured temperature settings in the BIOS to reduce fan noise. I also placed the computer behind my entertainment console to further block fan noise but positioned so I can reach the power button. + +The result is a simple machine that is not overly loud and uses only two cables—AC power and HDMI. It should be able to run any mainstream or specialized media center Linux distribution. I don't expect to do too much high-end gaming because that may require more processing horsepower. + +![Showing Ubuntu Linux About page onscreen][7] + +Ubuntu Linux About page. + +![YouTube on the big screen][9] + +Testing a YouTube video on the big screen. + +I haven't yet installed a dedicated media center distribution of Linux like [Kodi][10]. For now, it is running Ubuntu Linux 18.04.1 LTS and is very stable. + +This was a fun challenge to make the best of what I already had rather than buying new hardware. This is just one benefit of open source software. Eventually, I will probably replace it with a smaller, quieter system with a media-center case or another small box, but for now, it meets my needs quite well. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/11/old-linux-desktop-new-home-media-center + +作者：[Alan Formy-Duval][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/alanfdoss +[b]: https://github.com/lujun9972 +[2]: https://opensource.com/sites/default/files/uploads/soundsettings.png (Sound settings screenshot) +[3]: https://pwr.github.io/Solaar/ +[5]: https://opensource.com/sites/default/files/uploads/solaar_interface.png (Solaar) +[7]: https://opensource.com/sites/default/files/uploads/finalresult1.png (Showing Ubuntu Linux About page onscreen) +[9]: https://opensource.com/sites/default/files/uploads/finalresult2.png (YouTube on the big screen) +[10]: https://kodi.tv/ diff --git a/sources/tech/20181129 The Top Command Tutorial With Examples For Beginners.md b/sources/tech/20181129 The Top Command Tutorial With Examples For Beginners.md new file mode 100644 index 0000000000..df932ebb83 --- /dev/null +++ b/sources/tech/20181129 The Top Command Tutorial With Examples For Beginners.md @@ -0,0 +1,192 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (The Top Command Tutorial With Examples For Beginners) +[#]: via: (https://www.ostechnix.com/the-top-command-tutorial-with-examples-for-beginners/) +[#]: author: ([SK](https://www.ostechnix.com/author/sk/)) +[#]: url: ( ) + +The Top Command Tutorial With Examples For Beginners +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/top-command-720x340.png) + +As a Linux administrator, you may need to need to know some basic details of your Linux system, such as the currently running processes, average system load, cpu and memory usage etc., at some point. Thankfully, we have a command line utility called **“top”** to get such details. The top command is a well-known and most widely used utility to display dynamic real-time information about running processes in Unix-like operating systems. In this brief tutorial, we are going to see some common use cases of top command. + +### Top Command Examples + +**Monitor all processes** + +To start monitoring the running processes, simply run the top command without any options: + +``` +$ top +``` + +Sample output: + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/top-command-1.png) + +As you see in the above screenshot, top command displays the list of processes in multiple columns. Each column displays details such as pid, user, cpu usage, memory usage. Apart from the list of processes, you will also see the brief stats about average system load, number of tasks, cpu usage, memory usage and swap usage on the top. + +Here is the explanation of the parameters mentioned above. + + * **PID** – Process id of the task. + * **USER** – Username of the the task’s owner. + * **PR** – Priority of the task. + * **NI** – Nice value of the task. If the nice value is negative, the process gets higher priority. If the nice value is positive, the priority is low. Refer [**this guide**][1] to know more about nice. + * **VIRT** – Total amount of virtual memory used by the task. + * **RES** – Resident Memory Size, the non-swapped physical memory a task is currently using. + * **SHR** – Shared Memory Size. The amount of shared memory used by a task. + * **S** – The status of the process (S=sleep R=running Z=zombie). + * **%CPU** – CPU usage. The task’s share of the elapsed CPU time since the last screen update, expressed as a percentage of total CPU time. + * **%MEM** – Memory Usage. A task’s currently resident share of available physical memory. + * **TIME+** – Total CPU time used by the task since it has started, precise to the hundredths of a second. + * **COMMAND** – Name of the running program. + + + +**Display path of processes** + +If you want to see the absolute path of the running processes, just press **‘c’**. Now you will see the actual path of the programs under the COMMAND column in the below screenshot. + +![][3] + +**Monitor processes owned by a specific user** + +If you run top command without any options, it will list all running processes owned by all users. How about displaying processes owned by a specific user? It is easy! To show the processes owned by a given user, for example **sk** , simply run: + +``` +$ top -u sk +``` + +![](https://www.ostechnix.com/wp-content/uploads/2018/11/top-command-3.png) + +**Do not show idle/zombie processes** + +Instead of viewing all processes, you can simply ignore the idle or zombie processes. The following command will not show any idle or zombie processes: + +``` +$ top -i +``` + +**Monitor processes with PID** + +If you know the PID of any processes, for example 21180, you can monitor that process using **-p** flag. + +``` +$ top -p 21180 +``` + +You can specify multiple PIDs with comma-separated values. + +**Monitor processes with process name** + +I don’t know PID, but know only the process name. How to monitor it? Simple! + +``` +$ top -p $(pgrep -d ',' firefox) +``` + +Here, **firefox** is the process name and **‘pgrep -d’** picks the respective PID from the process name. + +**Display processes by CPU usage** + +Sometimes, you might want to display processes sorted by CPU usage. If so, use the following command: + +``` +$ top -o %CPU +``` + +![][4] + +The processes with higher CPU usage will be displayed on the top. Alternatively, you sort the processes by CPU usage by pressing **SHIFT+p**. + +**Display processes by Memory usage** + +Similarly, to order processes by memory usage, the command would be: + +``` +$ top -o %MEM +``` + +**Renice processes** + +You can change the priority of a process at any time using the option **‘r’**. Run the top command and press **r** and type the PID of a process to change its priority. + +![][5] + +Here, **‘r’** refers renice. + +**Set update interval** + +Top program has an option to specify the delay between screen updates. If want to change the delay-time, say 5 seconds, run: + +``` +$ top -d 5 +``` + +The default value is **3.0** seconds. + +If you already started the top command, just press **‘d’** and type delay-time and hit ENTER key. + +![][6] + +**Set number of iterations (repetition)** + +By default, top command will keep running until you press **q** to exit. However, you can set the number of iterations after which top will end. For instance, to exit top command automatically after 5 iterations, run: + +``` +$ top -n 5 +``` + +**Kill running processes** + +To kill a running process, simply press **‘k’** and type its PID and hit ENTER key. + +![][7] + +Top command supports few other options as well. For example, press **‘z’** to switch between mono and color output. It will help you to easily highlight running processes. + +![][8] + +Press **‘h’** to view all available keyboard shortcuts and help section. + +To quit top, just press **q**. + +At this stage, you will have a basic understanding of top command. For more details, refer man pages. + +``` +$ man top +``` + +As you can see, using Top command to monitor the running processes isn’t that hard. Top command is easy to learn and use! + +And, that’s all for now. More good stuffs to come. Stay tuned! + +Cheers! + + + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/the-top-command-tutorial-with-examples-for-beginners/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: https://www.ostechnix.com/change-priority-process-linux/ +[2]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[3]: http://www.ostechnix.com/wp-content/uploads/2018/11/top-command-2.png +[4]: http://www.ostechnix.com/wp-content/uploads/2018/11/top-command-4.png +[5]: http://www.ostechnix.com/wp-content/uploads/2018/11/top-command-8.png +[6]: http://www.ostechnix.com/wp-content/uploads/2018/11/top-command-7.png +[7]: http://www.ostechnix.com/wp-content/uploads/2018/11/top-command-5.png +[8]: http://www.ostechnix.com/wp-content/uploads/2018/11/top-command-6.png diff --git a/sources/tech/20181202 How To Customize The GNOME 3 Desktop.md b/sources/tech/20181202 How To Customize The GNOME 3 Desktop.md new file mode 100644 index 0000000000..91c16e4e99 --- /dev/null +++ b/sources/tech/20181202 How To Customize The GNOME 3 Desktop.md @@ -0,0 +1,266 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (How To Customize The GNOME 3 Desktop?) +[#]: via: (https://www.2daygeek.com/how-to-customize-the-gnome-3-desktop/) +[#]: author: (Magesh Maruthamuthu https://www.2daygeek.com/author/magesh/) +[#]: url: ( ) + +How To Customize The GNOME 3 Desktop? +====== + +We have got many emails from user to write an article about GNOME 3 desktop customization but we don’t get a time to write this topic. + +I was using Ubuntu operating system since long time in my primary laptop and i got bored so, i would like to test some other distro which is related to Arch Linux. + +I prefer to go with Majaro so, i have installed Manjaro 18.0 with GNOME 3 desktop in my laptop. + +I’m customizing my desktop, how i want it. So, i would like to take this opportunity to write up this article in detailed way to help others. + +This article helps others to customize their desktop without headache. + +I’m not going to include all my customization and i will be adding a necessary things which will be mandatory and useful for Linux desktop users. + +If you feel some tweak is missing in this article, i would request you to mention that in comment sections. It will be very helpful for other users. + +### 1) How to Launch Activities Overview in GNOME 3 Desktop? + +The Activities Overview will display all the running applications or launched/opened windows by clicking `Super Key` or by clicking `Activities` button in the topmost left corner. + +It allows you to launch a new applications, switch windows, and move windows between workspaces. + +You can simply exit the Activities Overview by choosing the following any of the one actions like selecting a window, application or workspace, or by pressing the `Super Key` or `Esc Key`. + +Activities Overview Screenshot. +![][2] + +### 2) How to Resize Windows in GNOME 3 Desktop? + +The Launched windows can be maximized, unmaximized and snapped to one side of the screen (Left or Right) by using the following key combinations. + + * `Super Key+Down Arrow:` To unmaximize the window. + * `Super Key+Up Arrow:` To maximize the window. + * `Super Key+Right Arrow:` To fill a window in the right side of the half screen. + * `Super Key+Left Arrow:` To fill a window in the left side of the half screen + + + +Use `Super Key+Down Arrow` to unmaximize the window. +![][3] + +Use `Super Key+Up Arrow` to maximize the window. +![][4] + +Use `Super Key+Right Arrow` to fill a window in the right side of the half screen. +![][5] + +Use `Super Key+Left Arrow` to fill a window in the left side of the half screen. +![][6] + +This feature will help you to view two applications at a time a.k.a splitting screen. +![][7] + +### 3) How to Display Applications in GNOME 3 Desktop? + +Click on the `Show Application Grid` button in the Dash to display all the installed applications on your system. +![][8] + +### 4) How to Add Applications on Dash in GNOME 3 Desktop? + +To speed up your day to day activity you may want to add frequently used application into Dash or Drag the application launcher to the Dash. + +It will allow you to directly launch your favorite applications without searching them. To do so, simply right click on it and use the option `Add to Favorites`. +![][9] + +To remove a application launcher a.k.a favorite from Dash, either drag it from the Dash to the grid button or simply right click on it and use the option `Remove from Favorites`. +![][10] + +### 5) How to Switch Between Workspaces in GNOME 3 Desktop? + +Workspaces allow you to group windows together. It will helps you to segregate your work properly. If you are working on Multiple things and you want to group each work and related things separately then it will be very handy and perfect option for you. + +You can switch workspaces in two ways, Open the Activities Overview and select a workspace from the right-hand side or use the following key combinations. + + * Use `Ctrl+Alt+Up` Switch to the workspace above. + * Use `Ctrl+Alt+Down` Switch to the workspace below. + + + +![][11] + +### 6) How to Switch Between Applications (Application Switcher) in GNOME 3 Desktop? + +Use either `Alt+Tab` or `Super+Tab` to switch between applications. To launch Application Switcher, use either `Alt+Tab` or `Super+Tab`. + +Once launched, just keep holding the Alt or Super key and hit the tab key to move to the next application from left to right order. + +### 7) How to Add UserName to Top Panel in GNOME 3 Desktop? + +If you would like to add your UserName to Top Panel then install the following [Add Username to Top Panel][12] GNOME Extension. +![][13] + +### 8) How to Add Microsoft Bing’s wallpaper in GNOME 3 Desktop? + +Install the following [Bing Wallpaper Changer][14] GNOME shell extension to change your wallpaper every day to Microsoft Bing’s wallpaper. +![][15] + +### 9) How to Enable Night Light in GNOME 3 Desktop? + +Night light app is one of the famous app which reduces strain on the eyes by turning your screen a dim yellow from blue light after sunset. + +It is available in smartphones. The other known apps for the same purpose are flux and **[redshift][16]**. + +To enable this, navigate to **System Settings** >> **Devices** >> **Displays** and turn Nigh Light on. +![][17] + +Once it’s enabled and status icon will be placed on the top panel. +![][18] + +### 10) How to Show the Battery Percentage in GNOME 3 Desktop? + +Battery percentage will show you the exact battery usage. To enable this follow the below steps. + +Start GNOME Tweaks >> **Top Bar** >> **Battery Percentage** and switch it on. +![][19] + +After modification you can able to see the battery percentage icon on the top panel. +![][20] + +### 11) How to Enable Mouse Right Click in GNOME 3 Desktop? + +By default right click is disabled on GNOME 3 desktop environment. To enable this follow the below steps. + +Start GNOME Tweaks >> **Keyboard & Mouse** >> Mouse Click Emulation and select “Area” option. +![][21] + +### 12) How to Enable Minimize On Click in GNOME 3 Desktop? + +Enable one-click minimize feature which will help us to minimize opened window without using minimize option. + +``` +$ gsettings set org.gnome.shell.extensions.dash-to-dock click-action 'minimize' +``` + +### 13) How to Customize Dock in GNOME 3 Desktop? + +If you would like to change your Dock similar to Deepin desktop or Mac then use the following set of commands. + +``` +$ gsettings set org.gnome.shell.extensions.dash-to-dock dock-position BOTTOM +$ gsettings set org.gnome.shell.extensions.dash-to-dock extend-height false +$ gsettings set org.gnome.shell.extensions.dash-to-dock transparency-mode FIXED +$ gsettings set org.gnome.shell.extensions.dash-to-dock dash-max-icon-size 50 +``` + +![][22] + +### 14) How to Show Desktop in GNOME 3 Desktop? + +By default `Super Key+D` shortcut doesn’t show your desktop. To configure this follow the below steps. + +Settings >> **Devices** >> **Keyboard** >> Click **Hide all normal windows** under Navigation then Press `Super Key+D` finally hit `Set` button to enable it. +![][23] + +### 15) How to Customize Date and Time Format? + +By default GNOME 3 shows date and time with `Sun 04:48`. It’s not clear and if you want to get the output with following format `Sun Dec 2 4:49 AM` follow the below steps. + +**For Date Modification:** Start GNOME Tweaks >> **Top Bar** and enable `Weekday` option under Clock. +![][24] + +**For Time Modification:** Settings >> **Details** >> **Date & Time** then choose `AM/PM` option in the time format. +![][25] + +After modification you can able to see the date and time format same as below. +![][26] + +### 16) How to Permanently Disable Unused Services in Boot? + +In my case, i’m not going to use **Bluetooth** & **cpus a.k.a Printer service**. Hence, disabling these services on my laptop. To disable services on Arch based systems use **[Pacman Package Manager][27]**. +For Bluetooth + +``` +$ sudo systemctl stop bluetooth.service +$ sudo systemctl disable bluetooth.service +$ sudo systemctl mask bluetooth.service +$ systemctl status bluetooth.service +``` + +For cups + +``` +$ sudo systemctl stop org.cups.cupsd.service +$ sudo systemctl disable org.cups.cupsd.service +$ sudo systemctl mask org.cups.cupsd.service +$ systemctl status org.cups.cupsd.service +``` + +Finally verify whether these services are disabled or not in the boot using the following command. If you want to double confirm this, you can reboot once and check the same. Navigate to the following link to know more about **[systemctl][28]** usage, + +``` +$ systemctl list-unit-files --type=service | grep enabled +[email protected] enabled +dbus-org.freedesktop.ModemManager1.service enabled +dbus-org.freedesktop.NetworkManager.service enabled +dbus-org.freedesktop.nm-dispatcher.service enabled +display-manager.service enabled +gdm.service enabled +[email protected] enabled +linux-module-cleanup.service enabled +ModemManager.service enabled +NetworkManager-dispatcher.service enabled +NetworkManager-wait-online.service enabled +NetworkManager.service enabled +systemd-fsck-root.service enabled-runtime +tlp-sleep.service enabled +tlp.service enabled +``` + +### 17) Install Icons & Themes in GNOME 3 Desktop? + +Bunch of Icons and Themes are available for GNOME Desktop so, choose the desired **[GTK Themes][29]** and **[Icons Themes][30]** for you. To configure this further, navigate to the below links which makes your Desktop more elegant. + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/how-to-customize-the-gnome-3-desktop/ + +作者：[Magesh Maruthamuthu][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/magesh/ +[b]: https://github.com/lujun9972 +[1]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[2]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-activities-overview-screenshot.jpg +[3]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-activities-unmaximize-the-window.jpg +[4]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-activities-maximize-the-window.jpg +[5]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-activities-fill-a-window-right-side.jpg +[6]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-activities-fill-a-window-left-side.jpg +[7]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-activities-split-screen.jpg +[8]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-display-applications.jpg +[9]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-add-applications-on-dash.jpg +[10]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-remove-applications-from-dash.jpg +[11]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-workspaces-screenshot.jpg +[12]: https://extensions.gnome.org/extension/1108/add-username-to-top-panel/ +[13]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-add-username-to-top-panel.jpg +[14]: https://extensions.gnome.org/extension/1262/bing-wallpaper-changer/ +[15]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-add-microsoft-bings-wallpaper.jpg +[16]: https://www.2daygeek.com/install-redshift-reduce-prevent-protect-eye-strain-night-linux/ +[17]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-enable-night-light.jpg +[18]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-enable-night-light-1.jpg +[19]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-display-battery-percentage.jpg +[20]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-display-battery-percentage-1.jpg +[21]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-enable-mouse-right-click.jpg +[22]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-dock-customization.jpg +[23]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-enable-show-desktop.jpg +[24]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-customize-date.jpg +[25]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-customize-time.jpg +[26]: https://www.2daygeek.com/wp-content/uploads/2018/12/how-to-customize-the-gnome-3-desktop-customize-date-time.jpg +[27]: https://www.2daygeek.com/pacman-command-examples-manage-packages-arch-linux-system/ +[28]: https://www.2daygeek.com/sysvinit-vs-systemd-cheatsheet-systemctl-command-usage/ +[29]: https://www.2daygeek.com/category/gtk-theme/ +[30]: https://www.2daygeek.com/category/icon-theme/ diff --git a/sources/tech/20181203 ANGRYsearch - Quick Search GUI Tool for Linux.md b/sources/tech/20181203 ANGRYsearch - Quick Search GUI Tool for Linux.md new file mode 100644 index 0000000000..7c8952549f --- /dev/null +++ b/sources/tech/20181203 ANGRYsearch - Quick Search GUI Tool for Linux.md @@ -0,0 +1,108 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (ANGRYsearch – Quick Search GUI Tool for Linux) +[#]: via: (https://itsfoss.com/angrysearch/) +[#]: author: (John Paul https://itsfoss.com/author/john/) +[#]: url: ( ) + +ANGRYsearch – Quick Search GUI Tool for Linux +====== + +A search application is one of the most important tools you can have on your computer. Most are slow to indexes your system and find results. However, today we will be looking at an application that can display results as you type. Today, we will be looking at ANGRYsearch. + +### What is ANGRYsearch? + +![][1] +Newly installed ANGRYsearch + +[ANGRYsearch][2] is a Python-based application that delivers results as you type your search query. The overall idea and design of the application are both inspired by [Everything][3] a search tool for Windows. (I discovered Everything ad couple of years ago and install it wherever I use Windows.) + +ANGRYsearch is able to display the search results so quickly because it only indexes filenames. After you install ANGRYsearch, you create a database of filenames by indexing your system. ANGRYsearch then quickly filters filenames as you type your query. + +Even though there is not much to ANGRYsearch, there are several things you can do to customize the experience. First, ANGRYsearch has two different display modes: lite and full. Lite mode only shows the filename and path. Full mode displays filename, path, size, and date of the last modification. Full mode, obviously, takes longer to display. The default is lite mode. In order to switch to full mode, you need to edit the config file at `~/.config/angrysearch/angrysearch.conf`. In that file change the `angrysearch_lite` value to false. + +ANGRYsearch also has three different search modes: fast, slow, and regex. Fast mode displays filenames that start with your search term. For example, if you had a folder full of the latest releases of a bunch of Linux distros and you searched “Ubuntu”, ANGRYsearch would display Ubuntu, Ubuntu Mate, Ubuntu Budgie, but not Kubuntu, Xubuntu, or Lubuntu. Fast mode is on by default and can be turned off by unchecking the checkbox next to the “update” button. Slow mode is slightly slower (obviously), but it will display files that have your search term anywhere in their name. In the previous example, ANGRYsearch would show all Ubuntu distros. Regex mode is the slowest and most precise. It uses [regular expressions][4] and is case insensitive. Regex mode is activated by pressing F8. + +You can also tell ANGRYsearch to ignore certain folders when it indexes your system. Just click the “update” button and enter the names of the folders you want to be ignored in the space provided. You can also choose from several icon themes, though it doesn’t make that much difference. + +![][5]Fast mode results + +### Installing ANGRYsearch on Linux + +ANGRYsearch is available in the [Arch User Repository][6]. It has also been packaged for [Fedora and openSUSE][7]. + +To install on other distros, follow these instructions. Instructions are written for a Debian or Ubuntu based system. + +ANGRYsearch depends on `python3-pyqt5` and`xdg-utils` so you will need to install them first. Most distros have `xdg-utils`already installed. + +`sudo apt install python3-pyqt5` + +Next. download the latest version (1.0.1). + +`wget https://github.com/DoTheEvo/ANGRYsearch/archive/v1.0.1.zip` + +Now, unzip the archive file. + +`unzip v1.0.1.zip` + +Next, we will navigate to the new folder (ANGRYsearch-1.0.1) and run the installer. + +`cd ANGRYsearch-1.0.1` + +`chmod +x install.sh` + +`sudo ./install.sh` + +The installation process is very quick, so don’t be surprised when a new command line is displayed as soon as you hit `Enter`. + +The first time that you start ANGRYsearch, you will need to index your system. ANGRYsearch does not automatically keep its database updated. You can use `crontab` to schedule a system scan. + +To open a text editor to create a new cronjob, use `crontab -e`. To make sure that the ANGRYsearch database is updated every 6 hours, use this command `0 */6 选题模板.txt 中文排版指北.md core.md Dict.md lctt2014.md lctt2016.md lctt2018.md LCTT翻译规范.md LICENSE published README.md scripts sources translated 选题模板.txt 中文排版指北.md core.md Dict.md lctt2014.md lctt2016.md lctt2018.md LCTT翻译规范.md LICENSE published README.md scripts sources translated 选题模板.txt 中文排版指北.md core.md Dict.md lctt2014.md lctt2016.md lctt2018.md LCTT翻译规范.md LICENSE published README.md scripts sources translated /usr/share/angrysearch/angrysearch_update_database.py`. `crontab` does not run the job if it is powered off when the timer does off. In some case, you may need to manually update the database, but it should not take long. + +![][8]ANGRYsearch update/options menu + +### Experience + +In the past, I was always frustrated by how painfully slow it was to search my computer. I knew that Windows had the Everything app, but I thought Linux out of luck. It didn’t even occur to me to look for something similar on Linux. I’m glad I accidentally stumbled upon ANGRYsearch. + +I know there will be quite a few people complaining that ANGRYsearch only searches filenames, but most of the time that is all I need. Thankfully, most of the time I only need to remember part of the name to find what I am looking for. + +The only thing that annoys me about ANGRYsearch is that fact that it does not automatically update its database. You’d think there would be a way for the installer to create a cron job when you install it. + +![][9]Slow mode results + +### Final Thoughts + +Since ANGRYsearch is basically a Linux port of one of my favorite Windows apps, I’m pretty happy with it. I plan to install it on all my systems going forward. + +I know that I have ragged on other Linux apps for not being packaged for easy install, but I can’t do the same for ANGRYsearch. The installation process is pretty easy. I would definitely recommend it for Linux noobs. + +Have you ever used [ANGRYsearch][2]? If not, what is your favorite Linux search application? Let us know in the comments below. + +If you found this article interesting, please take a minute to share it on social media, Hacker News or [Reddit][10]. + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/angrysearch/ + +作者：[John Paul][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/john/ +[b]: https://github.com/lujun9972 +[1]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/11/angrysearch3.jpg?resize=800%2C627&ssl=1 +[2]: https://github.com/dotheevo/angrysearch/ +[3]: https://www.voidtools.com/ +[4]: http://www.aivosto.com/articles/regex.html +[5]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/angrysearch1.jpg?resize=800%2C627&ssl=1 +[6]: https://aur.archlinux.org/packages/angrysearch/ +[7]: https://software.opensuse.org/package/angrysearch +[8]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/angrysearch2.jpg?resize=800%2C626&ssl=1 +[9]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/angrysearch4.jpg?resize=800%2C627&ssl=1 +[10]: http://reddit.com/r/linuxusersgroup diff --git a/sources/tech/20181203 How to bring good fortune to your Linux terminal.md b/sources/tech/20181203 How to bring good fortune to your Linux terminal.md new file mode 100644 index 0000000000..7549dc0249 --- /dev/null +++ b/sources/tech/20181203 How to bring good fortune to your Linux terminal.md @@ -0,0 +1,86 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: subject: (How to bring good fortune to your Linux terminal) +[#]: via: (https://opensource.com/article/18/12/linux-toy-fortune) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) +[#]: url: ( ) + +How to bring good fortune to your Linux terminal +====== +Bring quotes and quips to the command line with the fortune utility. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-fortune.png?itok=5PVVZVer) + +It's December, and if you haven't found a [tech advent calendar][1] that sparks your fancy yet, well, maybe this one will do the trick. Every day, from now to the 24th, we're bringing you a different Linux command-line toy. What's a command-line toy, you ask? It could be a game or any simple diversion to bring a little happiness to your terminal. + +You may have seen some of these before. We hope you'll find something new, too. Either way, we hope you have fun following along. + +Today's toy, **fortune** , is an old one. Versions of it date back to the 1980s when it was included with Unix. The version I installed in Fedora was available under a BSD license, and I grabbed it with the following. + +``` +$ sudo dnf install fortune-mod -y +``` + +Your distribution may be different. On some, you may need to install the fortunes separately from **fortune** itself (try searching your package manager for "fortunes*"). You can also check out the source code on [GitHub][2]. Then, just run **fortune** to get, well, a fortune. + +``` +$ fortune +"Time is an illusion.  Lunchtime doubly so." +-- Ford Prefect, _Hitchhiker's Guide to the Galaxy_ +``` + +So why do you need fortunes at the terminal? For fun, of course. Perhaps you'd like to add them to the message of the day on your system? + +Personally, I like using the **fortune** command as a built-in piece of dummy data when I'm using the terminal to parse text, particularly with [regular expressions][3], and want something simple to try it out on. + +For example, let's say I was testing our a transformation with the **tr** command to replace letter the letter e with a numeral 3. + +``` +$ fortune | tr 'eE' '3' +Unix 3xpr3ss: +All pass3ng3r bring a pi3c3 of th3 a3roplan3 and a box of tools with th3m to +th3 airport. Th3y gath3r on th3 tarmac, arguing constantly about what kind +of plan3 th3y want to build and how to put it tog3th3r. 3v3ntually, th3 +pass3ng3rs split into groups and build s3v3ral diff3r3nt aircraft, but giv3 +th3m all th3 sam3 nam3. Som3 pass3ng3rs actually r3ach th3ir d3stinations. +All pass3ng3rs b3li3v3 th3y got th3r3. +``` + +So what fortunes come with your distribution? Take a look in your **/usr/share/games/fortune** directory to find them all. Here are a few of my favorites. + +``` +Never laugh at live dragons. +                -- Bilbo Baggins [J.R.R. Tolkien, "The Hobbit"] + +I dunno, I dream in Perl sometimes... +             -- Larry Wall in  <8538@jpl-devvax.JPL.NASA.GOV> + +I have an existential map.  It has "You are here" written all over it. +                -- Steven Wright +``` + +Looking for more on **fortune**? You can, of course, always check out the man page to learn more about the options, or read a little bit more about the history of the command on [Wikipedia][4]. + +Do you have a favorite command-line toy that you think I ought to profile? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [Drive a locomotive through your Linux terminal][5], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-fortune + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/16/11/7-tech-advent-calendars-holiday-season +[2]: https://github.com/shlomif/fortune-mod +[3]: https://opensource.com/article/18/5/getting-started-regular-expressions +[4]: https://en.wikipedia.org/wiki/Fortune_%28Unix%29 +[5]: https://opensource.com/article/18/12/linux-toy-sl diff --git a/sources/tech/20181204 4 Unique Terminal Emulators for Linux.md b/sources/tech/20181204 4 Unique Terminal Emulators for Linux.md new file mode 100644 index 0000000000..04110b670e --- /dev/null +++ b/sources/tech/20181204 4 Unique Terminal Emulators for Linux.md @@ -0,0 +1,169 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (4 Unique Terminal Emulators for Linux) +[#]: via: (https://www.linux.com/blog/learn/2018/12/4-unique-terminals-linux) +[#]: author: (Jack Wallen https://www.linux.com/users/jlwallen) + +4 Unique Terminal Emulators for Linux +====== +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_main.jpg?itok=e6av-5VO) +Let’s face it, if you’re a Linux administrator, you’re going to work with the command line. To do that, you’ll be using a terminal emulator. Most likely, your distribution of choice came pre-installed with a default terminal emulator that gets the job done. But this is Linux, so you have a wealth of choices to pick from, and that ideology holds true for terminal emulators as well. In fact, if you open up your distribution’s GUI package manager (or search from the command line), you’ll find a trove of possible options. Of those, many are pretty straightforward tools; however, some are truly unique. + +In this article, I’ll highlight four such terminal emulators, that will not only get the job done, but do so while making the job a bit more interesting or fun. So, let’s take a look at these terminals. + +### Tilda + +[Tilda][1] is designed for Gtk and is a member of the cool drop-down family of terminals. That means the terminal is always running in the background, ready to drop down from the top of your monitor (such as Guake and Yakuake). What makes Tilda rise above many of the others is the number of configuration options available for the terminal (Figure 1). +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_1.jpg?itok=bra6qb6X) + +Tilda can be installed from the standard repositories. On a Ubuntu- (or Debian-) based distribution, the installation is as simple as: + +``` +sudo apt-get install tilda -y +``` + +Once installed, open Tilda from your desktop menu, which will also open the configuration window. Configure the app to suit your taste and then close the configuration window. You can then open and close Tilda by hitting the F1 hotkey. One caveat to using Tilda is that, after the first run, you won’t find any indication as to how to reach the configuration wizard. No worries. If you run the command tilda -C it will open the configuration window, while still retaining the options you’ve previously set. + +Available options include: + + * Terminal size and location + + * Font and color configurations + + * Auto Hide + + * Title + + * Custom commands + + * URL Handling + + * Transparency + + * Animation + + * Scrolling + + * And more + + + + +What I like about these types of terminals is that they easily get out of the way when you don’t need them and are just a button click away when you do. For those that hop in and out of the terminal, a tool like Tilda is ideal. + +### Aterm + +Aterm holds a special place in my heart, as it was one of the first terminals I used that made me realize how flexible Linux was. This was back when AfterStep was my window manager of choice (which dates me a bit) and I was new to the command line. What Aterm offered was a terminal emulator that was highly customizable, while helping me learn the ins and outs of using the terminal (how to add options and switches to a command). “How?” you ask. Because Aterm never had a GUI for customization. To run Aterm with any special options, it had to run as a command. For example, say you want to open Aterm with transparency enabled, green text, white highlights, and no scroll bar. To do this, issue the command: + +``` +aterm -tr -fg green -bg white +xb +``` + +The end result (with the top command running for illustration) would look like that shown in Figure 2. + +![Aterm][3] + +Figure 2: Aterm with a few custom options. + +[Used with permission][4] + +Of course, you must first install Aterm. Fortunately, the application is still found in the standard repositories, so installing on the likes of Ubuntu is as simple as: + +``` +sudo apt-get install aterm -y +``` + +If you want to always open Aterm with those options, your best bet is to create an alias in your ~/.bashrc file like so: + +``` +alias=”aterm -tr -fg green -bg white +sb” +``` + +Save that file and, when you issue the command aterm, it will always open with those options. For more about creating aliases, check out [this tutorial][5]. + +### Eterm + +Eterm is the second terminal that really showed me how much fun the Linux command line could be. Eterm is the default terminal emulator for the Enlightenment desktop. When I eventually migrated from AfterStep to Enlightenment (back in the early 2000s), I was afraid I’d lose out on all those cool aesthetic options. That turned out to not be the case. In fact, Eterm offered plenty of unique options, while making the task easier with a terminal toolbar. With Eterm, you can easily select from a large number of background images (should you want one - Figure 3) by selecting from the Background > Pixmap menu entry. + +![Eterm][7] + +Figure 3: Selecting from one of the many background images for Eterm. + +[Used with permission][4] + +There are a number of other options to configure (such as font size, map alerts, toggle scrollbar, brightness, contrast, and gamma of background images, and more). The one thing you want to make sure is, after you’ve configured Eterm to suit your tastes, to click Eterm > Save User Settings (otherwise, all settings will be lost when you close the app). + +Eterm can be installed from the standard repositories, with a command such as: + +``` +sudo apt-get install eterm +``` + +### Extraterm + +[Extraterm][8] should probably win a few awards for coolest feature set of any terminal window project available today. The most unique feature of Extraterm is the ability to wrap commands in color-coded frames (blue for successful commands and red for failed commands - Figure 4). + +![Extraterm][10] + +Figure 4: Extraterm showing two failed command frames. + +[Used with permission][4] + +When you run a command, Extraterm will wrap the command in an isolated frame. If the command succeeds, the frame will be outlined in blue. Should the command fail, the frame will be outlined in red. + +Extraterm cannot be installed via the standard repositories. In fact, the only way to run Extraterm on Linux (at the moment) is to [download the precompiled binary][11] from the project’s GitHub page, extract the file, change into the newly created directory, and issue the command ./extraterm. + +Once the app is running, to enable frames you must first enable bash integration. To do that, open Extraterm and then right-click anywhere in the window to reveal the popup menu. Scroll until you see the entry for Inject Bash shell Integration (Figure 5). Select that entry and you can then begin using the frames option. + +![Extraterm][13] + +Figure 5: Injecting Bash integration for Extraterm. + +[Used with permission][4] + +If you run a command, and don’t see a frame appear, you probably have to create a new frame for the command (as Extraterm only ships with a few default frames). To do that, click on the Extraterm menu button (three horizontal lines in the top right corner of the window), select Settings, and then click the Frames tab. In this window, scroll down and click the New Rule button. You can then add a command you want to work with the frames option (Figure 6). + +![frames][15] + +Figure 6: Adding a new rule for frames. + +[Used with permission][4] + +If, after this, you still don’t see frames appearing, download the extraterm-commands file from the [Download page][11], extract the file, change into the newly created directory, and issue the command sh setup_extraterm_bash.sh. That should enable frames for Extraterm. +There’s plenty more options available for Extraterm. I’m convinced, once you start playing around with this new take on the terminal window, you won’t want to go back to the standard terminal. Hopefully the developer will make this app available to the standard repositories soon (as it could easily become one of the most popular terminal windows in use). + +### And Many More + +As you probably expected, there are quite a lot of terminals available for Linux. These four represent (at least for me) four unique takes on the task, each of which do a great job of helping you run the commands every Linux admin needs to run. If you aren’t satisfied with one of these, give your package manager a look to see what’s available. You are sure to find something that works perfectly for you. + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/learn/2018/12/4-unique-terminals-linux + +作者：[Jack Wallen][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.linux.com/users/jlwallen +[b]: https://github.com/lujun9972 +[1]: http://tilda.sourceforge.net/tildadoc.php +[2]: https://www.linux.com/files/images/terminals2jpg +[3]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_2.jpg?itok=gBkRLwDI (Aterm) +[4]: https://www.linux.com/licenses/category/used-permission +[5]: https://www.linux.com/blog/learn/2018/12/aliases-diy-shell-commands +[6]: https://www.linux.com/files/images/terminals3jpg +[7]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_3.jpg?itok=RVPTJAtK (Eterm) +[8]: http://extraterm.org +[9]: https://www.linux.com/files/images/terminals4jpg +[10]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_4.jpg?itok=2n01qdwO (Extraterm) +[11]: https://github.com/sedwards2009/extraterm/releases +[12]: https://www.linux.com/files/images/terminals5jpg +[13]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_5.jpg?itok=FdaE1Mpf (Extraterm) +[14]: https://www.linux.com/files/images/terminals6jpg +[15]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/terminals_6.jpg?itok=lQ1Zv5wq (frames) diff --git a/sources/tech/20181206 How to view XML files in a web browser.md b/sources/tech/20181206 How to view XML files in a web browser.md new file mode 100644 index 0000000000..6060c792e2 --- /dev/null +++ b/sources/tech/20181206 How to view XML files in a web browser.md @@ -0,0 +1,109 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (How to view XML files in a web browser) +[#]: via: (https://opensource.com/article/18/12/xml-browser) +[#]: author: (Greg Pittman https://opensource.com/users/greg-p) + +How to view XML files in a web browser +====== +Turn XML files into something more useful. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/web_browser_desktop_devlopment_design_system_computer.jpg?itok=pfqRrJgh) + +Once you learn that HTML is a form of XML, you might wonder what would happen if you tried to view an XML file in a browser. The results are quite disappointing—Firefox shows you a banner at the top of the page that says, "This XML file does not appear to have any style information associated with it. The document tree is shown below." The document tree looks like the file would look in an editor: +![](https://opensource.com/sites/default/files/uploads/xml_menu.png) +This is the beginning of the **menu.xml** file for the online manual that comes with [Scribus][1], to which I'm a contributor. Although you see blue text, they are not clickable links. I wanted to be able to view this in a regular browser, since sometimes I need to go back and forth from the canvas in Scribus to the manual to figure out how to do something (maybe to see if I need to edit the manual to straighten out some misinformation or to add some missing information). + +The way to help a browser know what to do with these XML tags is by using XSLT—Extensible Stylesheet Language Transformations. In a broad sense, you could use XSLT to transform XML to a variety of outputs, or even HTML to XML. Here I want to use it to present the XML tags to a browser as suitable HTML. + +One slight modification needs to happen to the XML file: + +![](https://opensource.com/sites/default/files/uploads/xml_modified-menu.png) + +Adding this second line to the file tells the browser to look for a file named **scribus-manual.xsl** for the style information. The more important part is to create this XSL file. Here is the complete listing of **scribus-manual.xsl** for the Scribus manual: + +``` + + + +  +    +    Scribus Online Manual + + +        +                +                +        +
                  + +    + +      +        +         

                  +          +           

                  +                +                 

                    +                   
                    • +                 

                  +                                  +                            +        +         

                  +                          +                          +                        +    +    +                    +                   +``` + +This looks a lot more like HTML, and you can see it contains a number of HTML tags. After some preliminary tags and some particulars about displaying H2, H3, and H4 tags, you see a Table tag. This adds a graphical heading at the top of the page and uses some images already in the documentation files. + +After this, you get into the process of dissecting the various **submenuitem** tags, trying to create the nested listing structure as it appears in Scribus when you view the manual. One feature I did not try to duplicate is the ability to collapse and expand **submenuitem** areas. As you can imagine, it takes some time to sort through the number of nested lists you need to create, but when I finished, here is how it looked: + +![](https://opensource.com/sites/default/files/uploads/xml_scribusmenuinbrowser.png) + +This minimal editing to **menu.xml** does not interfere with Scribus' ability to show the manual in its own browser. I put this modified **menu.xml** file and the **scribus-manual.xsl** in the English documentation folder for 1.5.x versions of Scribus, so anyone using these versions can simply point their browser to the **menu.xml** file and it should show up just like you see above. + +A much bigger chore I took on a few years ago was to create a version of the ICD10 (International Classification of Diseases, version 10) when it came out. Many changes were made from the previous version (ICD9) to 10. These are important since these codes must be used for diagnostic purposes in medical practice. You can easily download XML files from the US [Centers for Medicare and Medicaid][2] website since it is public information, but—just as with the Scribus manual—these files are hard to use. + +Here is the beginning of the tabular listing of diseases: + +![](https://opensource.com/sites/default/files/uploads/xml_tabular_begin.png) + +One of the features I created was the color coding used in the listing shown here: + +![](https://opensource.com/sites/default/files/uploads/xml_tabular_body.png) + +As with **menu.xml** , the only editing I did in this **Tabular.xml** file was to add **** as the second line of the file. I started this project with the 2014 version, and I was quite pleased to find that the original **tabular.xsl** stylesheet worked perfectly when the 2016 version came out, which is the last one I worked on. The** Tabular.xml** file is 8.4MB, quite large for a plaintext file. It takes a few seconds to load into a browser, but once it's loaded, navigation is fast. + +While you may not often have to deal with an XML file in this way, if you do, I hope this article shows that your file can easily be turned into something much more usable. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/xml-browser + +作者：[Greg Pittman][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/greg-p +[b]: https://github.com/lujun9972 +[1]: https://www.scribus.net/ +[2]: https://www.cms.gov/ diff --git a/sources/tech/20181207 5 Screen Recorders for the Linux Desktop.md b/sources/tech/20181207 5 Screen Recorders for the Linux Desktop.md new file mode 100644 index 0000000000..4dd47e948a --- /dev/null +++ b/sources/tech/20181207 5 Screen Recorders for the Linux Desktop.md @@ -0,0 +1,177 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (5 Screen Recorders for the Linux Desktop) +[#]: via: (https://www.linux.com/blog/intro-to-linux/2018/12/5-screen-recorders-linux-desktop) +[#]: author: (Jack Wallen https://www.linux.com/users/jlwallen) + +5 Screen Recorders for the Linux Desktop +====== + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/screen-record.png?itok=tKWx29k8) + +There are so many reasons why you might need to record your Linux desktop. The two most important are for training and for support. If you are training users, a video recording of the desktop can go a long way to help them understand what you are trying to impart. Conversely, if you’re having trouble with one aspect of your Linux desktop, recording a video of the shenanigans could mean the difference between solving the problem and not. But what tools are available for the task? Fortunately, for every Linux user (regardless of desktop), there are options available. I want to highlight five of my favorite screen recorders for the Linux desktop. Among these five, you are certain to find one that perfectly meets your needs. I will only be focusing on those screen recorders that save as video. What video format you prefer may or may not dictate which tool you select. + +And, without further ado, let’s get on with the list. + +### Simple Screen Recorder + +I’m starting out with my go-to screen recorder. I use [Simple Screen Recorder][1] on a daily basis, and it never lets me down. This particular take on the screen recorder is available for nearly every flavor of Linux and is, as the name implies, very simple to use. With Simple Screen Recorder you can select a single window, a portion of the screen, or the entire screen to record. One of the best features of Simple Screen Recorder is the ability to save profiles (Figure 1), which allows you to configure the input for a recording (including scaling, frame rate, width, height, left edge and top edge spacing, and more). By saving profiles, you can easily use a specific profile to meet a unique need, without having to go through the customization every time. This is handy for those who do a lot of screen recording, with different input variables for specific jobs. + +![Simple Screen Recorder ][3] + +Figure 1: Simple Screen Recorder input profile window. + +[Used with permission][4] + +Simple screen recorder also: + + * Records audio input + + * Allows you to pause and resume recording + + * Offers a preview during recording + + * Allows for the selection of video containers and codecs + + * Adds timestamp to file name (optional) + + * Includes hotkey recording and sound notifications + + * Works well on slower machines + + * And much more + + + + +Simple Screen Recorder is one of the most reliable screen recording tools I have found for the Linux desktop. Simple Screen Recorder can be installed from the standard repositories on many desktops, or via easy to follow instructions on the [application download page][5]. + +### Gtk-recordmydesktop + +The next entry, [gtk-recordmydesktop][6], doesn’t give you nearly the options found in Simple Screen Recorder, but it does offer a command line component (for those who prefer not working with a GUI). The simplicity that comes along with this tool also means you are limited to a specific video output format (.ogv). That doesn’t mean gtk-recordmydesktop isn’t without appeal. In fact, there are a few features that make this option in the genre fairly appealing. First and foremost, it’s very simple to use. Second, the record window automatically gets out of your way while you record (as opposed to Simple Screen Recorder, where you need to minimize the recording window when recording full screen). Another feature found in gtk-recordmydesktop is the ability to have the recording follow the mouse (Figure 2). + +![gtk-recordmydesktop][8] + +Figure 2: Some of the options for gtk-recordmydesktop. + +[Used with permission][4] + +Unfortunately, the follow the mouse feature doesn’t always work as expected, so chances are you’ll be using the tool without this interesting option. In fact, if you opt to go the gtk-recordmydesktop route, you should understand the GUI frontend isn’t nearly as reliable as is the command line version of the tool. From the command line, you could record a specific position of the screen like so: + +``` +recordmydesktop -x X_POS -y Y_POS --width WIDTH --height HEIGHT -o FILENAME.ogv +``` + +where: + + * X_POS is the offset on the X axis + + * Y_POS is the offset on the Y axis + + * WIDTH is the width of the screen to be recorded + + * HEIGHT is the height of the screen to be recorded + + * FILENAME is the name of the file to be saved + + + + +To find out more about the command line options, issue the command man recordmydesktop and read through the manual page. + +### Kazam + +If you’re looking for a bit more than just a recorded screencast, you might want to give Kazam a go. Not only can you record a standard screen video (with the usual—albeit limited amount of—bells and whistles), you can also take screenshots and even broadcast video to YouTube Live (Figure 3). + +![Kazam][10] + +Figure 3: Setting up YouTube Live broadcasting in Kazam. + +[Used with permission][4] + +Kazam falls in line with gtk-recordmydesktop, when it comes to features. In other words, it’s slightly limited in what it can do. However, that doesn’t mean you shouldn’t give Kazam a go. In fact, Kazam might be one of the best screen recorders out there for new Linux users, as this app is pretty much point and click all the way. But if you’re looking for serious bells and whistles, look away. + +The version of Kazam, with broadcast goodness, can be found in the following repository: + +``` +ppa:sylvain-pineau/kazam +``` + +For Ubuntu (and Ubuntu-based distributions), install with the following commands: + +``` +sudo apt-add-repository ppa:sylvain-pineau/kazam + +sudo apt-get update + +sudo apt-get install kazam -y +``` + +### Vokoscreen + +The [Vokoscreen][11] recording app is for new-ish users who need more options. Not only can you configure the output format and the video/audio codecs, you can also configure it to work with a webcam (Figure 4). + +![Vokoscreen][13] + +Figure 4: Configuring a web cam for a Vokoscreen screen recording. + +[Used with permission][4] + +As with most every screen recording tool, Vokoscreen allows you to specify what on your screen to record. You can record the full screen (even selecting which display on multi-display setups), window, or area. Vokoscreen also allows you to select a magnification level (200x200, 400x200, or 600x200). The magnification level makes for a great tool to highlight a specific section of the screen (the magnification window follows your mouse). + +Like all the other tools, Vokoscreen can be installed from the standard repositories or cloned from its [GitHub repository][14]. + +### OBS Studio + +For many, [OBS Studio][15] will be considered the mack daddy of all screen recording tools. Why? Because OBS Studio is as much a broadcasting tool as it is a desktop recording tool. With OBS Studio, you can broadcast to YouTube, Smashcast, Mixer.com, DailyMotion, Facebook Live, Restream.io, LiveEdu.tv, Twitter, and more. In fact, OBS Studio should seriously be considered the de facto standard for live broadcasting the Linux desktop. + +Upon installation (the software is only officially supported for Ubuntu Linux 14.04 and newer), you will be asked to walk through an auto-configuration wizard, where you setup your streaming service (Figure 5). This is, of course, optional; however, if you’re using OBS Studio, chances are this is exactly why, so you won’t want to skip out on configuring your default stream. + +![OBS Studio][17] + +Figure 5: Configuring your streaming service for OBS Studio. + +[Used with permission][4] + +I will warn you: OBS Studio isn’t exactly for the faint of heart. Plan on spending a good amount of time getting the streaming service up and running and getting up to speed with the tool. But for anyone needing such a solution for the Linux desktop, OBS Studio is what you want. Oh … it can also record your desktop screencast and save it locally. + +### There’s More Where That Came From + +This is a short list of screen recording solutions for Linux. Although there are plenty more where this came from, you should be able to fill all your desktop recording needs with one of these five apps. + +Learn more about Linux through the free ["Introduction to Linux" ][18]course from The Linux Foundation and edX. + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/intro-to-linux/2018/12/5-screen-recorders-linux-desktop + +作者：[Jack Wallen][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.linux.com/users/jlwallen +[b]: https://github.com/lujun9972 +[1]: http://www.maartenbaert.be/simplescreenrecorder/ +[2]: /files/images/screenrecorder1jpg +[3]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/screenrecorder_1.jpg?itok=hZJ5xugI (Simple Screen Recorder ) +[4]: /licenses/category/used-permission +[5]: http://www.maartenbaert.be/simplescreenrecorder/#download +[6]: http://recordmydesktop.sourceforge.net/about.php +[7]: /files/images/screenrecorder2jpg +[8]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/screenrecorder_2.jpg?itok=TEGXaVYI (gtk-recordmydesktop) +[9]: /files/images/screenrecorder3jpg +[10]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/screenrecorder_3.jpg?itok=cvtFjxen (Kazam) +[11]: https://github.com/vkohaupt/vokoscreen +[12]: /files/images/screenrecorder4jpg +[13]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/screenrecorder_4.jpg?itok=c3KVS954 (Vokoscreen) +[14]: https://github.com/vkohaupt/vokoscreen.git +[15]: https://obsproject.com/ +[16]: /files/images/desktoprecorder5jpg +[17]: https://www.linux.com/sites/lcom/files/styles/rendered_file/public/desktoprecorder_5.jpg?itok=xyM-dCa7 (OBS Studio) +[18]: https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/sources/tech/20181207 Automatic continuous development and delivery of a hybrid mobile app.md b/sources/tech/20181207 Automatic continuous development and delivery of a hybrid mobile app.md new file mode 100644 index 0000000000..c513f36017 --- /dev/null +++ b/sources/tech/20181207 Automatic continuous development and delivery of a hybrid mobile app.md @@ -0,0 +1,102 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Automatic continuous development and delivery of a hybrid mobile app) +[#]: via: (https://opensource.com/article/18/12/hybrid-mobile-app-development) +[#]: author: (Angelo Manganiello https://opensource.com/users/amanganiello90) + +Automatic continuous development and delivery of a hybrid mobile app +====== +Hybrid apps are a good middle ground between native and web apps. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/idea_innovation_mobile_phone.png?itok=RqVtvxkd) + +Offering a mobile app is essentially a business requirement for organizations today. One of the first steps in developing an app is to understand the different types—native, hybrid (or cross-platform), and web—so you can decide which one will best meet your needs. + +### Native is better, right? + +**Native apps** represent the vast majority of applications that people download every day. Native applications are developed specifically for an operating system. Thus, a native iOS application will not work on an Android system and vice versa. To develop a native app, you need to know two things: + + 1. How to develop in a specific programming language (e.g., Swift for Apple devices; Java for Android) + 2. The app will not work for other platforms + + + +Even though native apps will work only on the platform they're developed for, they have several notable advantages over hybrid and web apps: + + * Increased speed, reliability, and responsiveness and higher resolution, all of which provide a better user experience + * May work offline/without internet service + * Easier access to all phone features (e.g., accelerometer, camera, microphone) + + + +### But my business is still linked to the web… + +Most companies have focused their resources on web development and now want to enter the mobile market. But many don't have the right technical resources to develop a native app for each platform. For these companies, **hybrid** development is the right choice. In this model, developers can use their existing frontend skills to develop a single, cross-platform mobile app. + +![Hybrid mobile apps][2] + +Hybrid apps are a good middle ground: they're faster and less expensive to develop than native apps, and they offer more possibilities than web apps. The tradeoffs are they don't perform as well as native apps and developers can't maintain their existing tight focus on web development (as they could with web apps). + +If you already are a fan of the [Angular][3] cross-platform development framework, I recommend trying the [Ionic][4] framework, which "lets web developers build, test, and deploy cross-platform hybrid mobile apps." I see Ionic as an extension of the [Apache Cordova][5] framework, which enables a normal web app (JS, HTML, or CSS) to run as a mobile app in a container. Ionic uses the base Cordova features that support the Angular development for its user interface. + +The advantage of this approach is simple: the Angular paradigm is maintained, so developers can continue writing [TypeScript][6] files but target a build for Android, iOS, and Windows by properly configuring the development environment. It also provides two important tools: + + * An appealing design and widget that are very similar to a native app's, so your hybrid app will look less "web" + * Cordova Plugins allow the app to communicate with all phone features + + + +### What about the Node.js backend? + +The programming world likes to standardize, which is why hybrid apps are so popular. Frontend developers' common skills are useful in the mobile world. But if we have a technology stack for the user interface, why not focus on a single backend with the same programming paradigm? + +This makes [Node.js][7] an appealing option. Node.js is a JavaScript runtime built on the Chrome V8 JavaScript engine. It can make the API development backend very fast and easy, and it integrates fully with web technologies. You can develop a Cordova plugin, using your Node.js backend, internally in your hybrid app, as I did with the [nodejs-cordova-plugin][8]. This plugin, following the Cordova guidelines, integrates a mobile-compatible version of the Node.js platform to provide a full-stack mobile app. + +If you need a simple CRUD Node.js backend, you can use my [API][9] [node generator][9] that generates an app using a [MongoDB][10] embedded database. + +![Cordova Full Stack application][12] + +### Deploying your app + +Open source offers everything you need to deploy your app in the best way. You just need a GitHub repository and a good continuous integration tool. I recommend [Travis-ci][13], an excellent tool that allows you to build and deploy your product for every commit. + +Travis-ci is a fork of the better known [Jenkins][14]. Like with Jenkins, you have to configure your pipeline through a configuration file (in this case a **.travis.yml** file) in your GitHub repo. See the [.travis.yml file][15] in my repository as an example. + +![](https://opensource.com/sites/default/files/uploads/3-travis-ci-process.png) + +In addition, this pipeline automatically delivers and installs your app on [Appetize.io][16], a web-based iOS simulator and Android emulator, for testing. + +You can learn more in the [Cordova Android][17] section of my GitHub repository. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/hybrid-mobile-app-development + +作者：[Angelo Manganiello][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/amanganiello90 +[b]: https://github.com/lujun9972 +[1]: /file/416441 +[2]: https://opensource.com/sites/default/files/uploads/1-title.png (Hybrid mobile apps) +[3]: https://angular.io/ +[4]: https://ionicframework.com/ +[5]: https://cordova.apache.org/ +[6]: https://www.typescriptlang.org/ +[7]: https://nodejs.org/ +[8]: https://github.com/fullStackApp/nodejs-cordova-plugin +[9]: https://github.com/fullStackApp/generator-full-stack-api +[10]: https://www.mongodb.com/ +[11]: /file/416351 +[12]: https://opensource.com/sites/default/files/uploads/2-cordova-full-stack-app.png (Cordova Full Stack application) +[13]: https://travis-ci.org/ +[14]: https://jenkins.io/ +[15]: https://github.com/amanganiello90/java-angular-web-app/blob/master/.travis.yml +[16]: https://appetize.io/ +[17]: https://github.com/amanganiello90/java-angular-web-app#cordova-android diff --git a/sources/tech/20181207 Plan your own holiday calendar at the Linux command line.md b/sources/tech/20181207 Plan your own holiday calendar at the Linux command line.md new file mode 100644 index 0000000000..b4d6f58b32 --- /dev/null +++ b/sources/tech/20181207 Plan your own holiday calendar at the Linux command line.md @@ -0,0 +1,132 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Plan your own holiday calendar at the Linux command line) +[#]: via: (https://opensource.com/article/18/12/linux-toy-cal) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Plan your own holiday calendar at the Linux command line +====== +Link commands together to build a colorful calendar, and then whisk it away in a snowstorm. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-cal.png?itok=S0F8RY9k) + +Welcome to today's installment of the Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself, what’s a command-line toy. Even I'm not quite sure, but generally, it could be a game or any simple diversion that helps you have fun at the terminal. + +It's quite possible that some of you will have seen various selections from our calendar before, but we hope there’s at least one new thing for everyone. + +We've somehow made it to the seventh day of our series without creating an actual calendar to celebrate with, so let's use a command-line tool to do that today: **cal**. By itself, **cal** is perhaps not the most amazing of tools, but we can use a few other utilities to spice it up a bit. + +Chances are, **cal** is installed on your system already. To use it in this instance, just type **cal**. + +``` +$ cal +    December 2018   +Su Mo Tu We Th Fr Sa +                   1 + 2  3  4  5  6  7  8 + 9 10 11 12 13 14 15 +16 17 18 19 20 21 22 +23 24 25 26 27 28 29 +30 31           +``` + +We aren't going to go into advanced usage in this article, so if you want to learn more about **cal** , go check out Opensource.com Community Moderator Don Watkin's excellent [overview of the date and cal commands][1]. + +Now, let's spice it up with a pretty box, as we covered in our previous Linux toy article. I'll use the diamonds box, and use a little bit of padding to get it nicely aligned. + +``` +$ cal | boxes -d diamonds -p a1l4t2  +       /\          /\          /\ +    /\//\\/\    /\//\\/\    /\//\\/\ + /\//\\\///\\/\//\\\///\\/\//\\\///\\/\ +//\\\//\/\\///\\\//\/\\///\\\//\/\\///\\ +\\//\/                            \/\\// + \/                                  \/ + /\           December 2018          /\ +//\\      Su Mo Tu We Th Fr Sa      //\\ +\\//                         1      \\// + \/        2  3  4  5  6  7  8       \/ + /\        9 10 11 12 13 14 15       /\ +//\\      16 17 18 19 20 21 22      //\\ +\\//      23 24 25 26 27 28 29      \\// + \/       30 31                      \/ + /\                                  /\ +//\\/\                            /\//\\ +\\///\\/\//\\\///\\/\//\\\///\\/\//\\\// + \/\\///\\\//\/\\///\\\//\/\\///\\\//\/ +    \/\\//\/    \/\\//\/    \/\\//\/ +       \/          \/          \/ +``` + +That looks nice, but for good measure, let's put the whole thing in a second box, just for fun. We'll use the scoll design this time. + +``` +cal | boxes -d diamonds -p a1t2l3 | boxes -a c -d scroll         + / ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ \ +|  /~~\                                              /~~\  | +|\ \   |         /\          /\          /\         |   / /| +| \   /|      /\//\\/\    /\//\\/\    /\//\\/\      |\   / | +|  ~~  |   /\//\\\///\\/\//\\\///\\/\//\\\///\\/\   |  ~~  | +|      |  //\\\//\/\\///\\\//\/\\///\\\//\/\\///\\  |      | +|      |  \\//\/                            \/\\//  |      | +|      |   \/                                  \/   |      | +|      |   /\          December 2018           /\   |      | +|      |  //\\     Su Mo Tu We Th Fr Sa       //\\  |      | +|      |  \\//                        1       \\//  |      | +|      |   \/       2  3  4  5  6  7  8        \/   |      | +|      |   /\       9 10 11 12 13 14 15        /\   |      | +|      |  //\\     16 17 18 19 20 21 22       //\\  |      | +|      |  \\//     23 24 25 26 27 28 29       \\//  |      | +|      |   \/      30 31                       \/   |      | +|      |   /\                                  /\   |      | +|      |  //\\/\                            /\//\\  |      | +|      |  \\///\\/\//\\\///\\/\//\\\///\\/\//\\\//  |      | +|      |   \/\\///\\\//\/\\///\\\//\/\\///\\\//\/   |      | +|      |      \/\\//\/    \/\\//\/    \/\\//\/      |      | +|      |         \/          \/          \/         |      | +|      |                                            |      | + \     |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|     / +  \   /                                              \   / +   ~~~                                                ~~~ +``` + +Perfect. Now, here's where things get a little crazy. I like our design, but, I'd like to go all out. So I'm going to colorize it. But here in the Raleigh, NC office where Opensource.com's staff are based, there's a good chance for snow this weekend. So let's enjoy our colorized advent calendar, and then wipe it out with snow. + +For the snow, I'm grabbing a nifty [snippet][2] of Bash and Gawk goodness I found over on CLIMagic. If you're not familiar with CLIMagic, go check out their [website][3] and follow them on [Twitter][4]. You'll be glad you did. + +So here we go. Let's clear the screen, throw up our boxy calendar, colorize it, wait a few seconds, then snowstorm it away. All here at the terminal, in one line. + +``` +$ clear;cal|boxes -d diamonds -p a1t2l3|boxes -a c -d scroll|lolcat;sleep 3;while :;do echo $LINES $COLUMNS $(($RANDOM%$COLUMNS)) $(printf "\u2744\n");sleep 0.1;done|gawk '{a[$3]=0;for(x in a) {o=a[x];a[x]=a[x]+1;printf "\033[%s;%sH ",o,x;printf "\033[%s;%sH%s \033[0;0H",a[x],x,$4;}}' +``` + +And there we go. + +![](https://opensource.com/sites/default/files/uploads/linux-toy-cal-animated.gif) + +For this to work on your system, you'll need all of the referenced utilities (boxes, lolcat, cal, gawk, etc.), and you'll need to use a terminal emulator that supports Unicode. + +Do you have a favorite command-line toy that you think I ought to profile? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [Take a break at the Linux command line with Nyan Cat][5], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-cal + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/16/12/using-calendar-function-linux +[2]: http://climagic.org/coolstuff/let-it-snow.html +[3]: http://climagic.org/ +[4]: https://twitter.com/climagic +[5]: https://opensource.com/article/18/12/linux-toy-nyancat diff --git a/sources/tech/20181209 Powers of two, powers of Linux- 2048 at the command line.md b/sources/tech/20181209 Powers of two, powers of Linux- 2048 at the command line.md new file mode 100644 index 0000000000..da1b241713 --- /dev/null +++ b/sources/tech/20181209 Powers of two, powers of Linux- 2048 at the command line.md @@ -0,0 +1,52 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Powers of two, powers of Linux: 2048 at the command line) +[#]: via: (https://opensource.com/article/18/12/linux-toy-2048) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Powers of two, powers of Linux: 2048 at the command line +====== +Looking for a terminal-based game to pass the time? Look no further than 2048-cli. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-2048.png?itok=3M6S-n1a) + +Hello and welcome to today's installment of the Linux command-line toys advent calendar. Every day, we look at a different toy for your terminal: it could be a game or any simple diversion that helps you have fun. + +Maybe you have seen various selections from our calendar before, but we hope there’s at least one new thing for everyone. + +Today's toy is a [command-line version][1] of one of my all-time favorite casual games, [2048][2] (which itself is a clone of another clone). + +To play, you just slide blocks up, down, left, and right to combine matching pairs and increment numbers, until you've made a block that is 2048 in size. The catch (and the challenge), is that you can't just move one block; instead, you move every block on the screen. + +It's simple, fun, and easy to get lost in it for hours. This 2048 clone, [2048-][1][cli][1], is by Marc Tiehuis and written in C, and made available as open source under an MIT license. You can find the source code [on GitHub][1], where you can also get installation instructions for your platform. Since it was packaged for Fedora, for me, installing it was as simple as: + +``` +$ sudo dnf install 2048-cli +``` + +That's it, have fun! + +![](https://opensource.com/sites/default/files/uploads/linux-toy-2048-animated_0.gif) + +Do you have a favorite command-line toy that you think I ought to profile? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [Play Tetris at your Linux terminal][3], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-2048 + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://github.com/tiehuis/2048-cli +[2]: https://github.com/gabrielecirulli/2048 +[3]: https://opensource.com/article/18/12/linux-toy-tetris diff --git a/sources/tech/20181210 Snake your way across your Linux terminal.md b/sources/tech/20181210 Snake your way across your Linux terminal.md new file mode 100644 index 0000000000..5ae452dcf5 --- /dev/null +++ b/sources/tech/20181210 Snake your way across your Linux terminal.md @@ -0,0 +1,52 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Snake your way across your Linux terminal) +[#]: via: (https://opensource.com/article/18/12/linux-toy-snake) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Snake your way across your Linux terminal +====== +Python isn't the only snake you'll find at the Linux command line with this classic 1970s game remake. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-snake.png?itok=oNhqUTDu) + +Welcome back to the Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is. It's hard to say exactly, but my definition is anything that helps you have fun at the terminal. + +We've been on a roll with games over the weekend, and it was fun, so let's look at one more game today, Snake! + +Snake is an oldie but goodie; versions of it have been around seemingly forever. The first version I remember playing was one called [Nibbles][1] that came packaged with [QBasic][2] in the 1990s, and was probably pretty important to my understanding of what a programming language even was. Here I had the source code to a game that I could modify and just see what happens, and maybe learn something about what all of those funny little words that made up a programming language were all about. + +Today's [Snake][3] is written in Go, and while it's simple, it's just as much fun as the original. Like most simple old games, there are a ton of versions to choose from. In Snake's case, there's even a version in the classic [bsdgames][4] package that's almost certainly packaged for your distribution. + +But what I like about this version of Snake is that it's packaged for Docker so I can easily run it in one line from my terminal without worrying about anything disto-specific. That, and it makes use of 15 randomized food emojis for the snake to eat. I'm a sucker for food emojis. Anyway, give it a try using: + +``` +$ docker run -ti dyego/snake-game +``` + +This Snake is licensed as open source under an MIT license, and you can check out the source code [on GitHub][3]. +![](https://opensource.com/sites/default/files/uploads/linux-toy-snake-animated.gif) +Do you have a favorite command-line toy that you think I ought to profile? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [Powers of two, powers of Linux: 2048 at the command line][5], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-snake + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://en.wikipedia.org/wiki/Nibbles_(video_game) +[2]: https://en.wikipedia.org/wiki/QBasic +[3]: https://github.com/DyegoCosta/snake-game +[4]: https://github.com/vattam/BSDGames +[5]: https://opensource.com/article/18/12/linux-toy-2048 diff --git a/sources/tech/20181211 How To Benchmark Linux Commands And Programs From Commandline.md b/sources/tech/20181211 How To Benchmark Linux Commands And Programs From Commandline.md new file mode 100644 index 0000000000..3962e361f3 --- /dev/null +++ b/sources/tech/20181211 How To Benchmark Linux Commands And Programs From Commandline.md @@ -0,0 +1,265 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (How To Benchmark Linux Commands And Programs From Commandline) +[#]: via: (https://www.ostechnix.com/how-to-benchmark-linux-commands-and-programs-from-commandline/) +[#]: author: (SK https://www.ostechnix.com/author/sk/) + +How To Benchmark Linux Commands And Programs From Commandline +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/benchmark-720x340.png) + +A while ago, I have written a guide about the [**alternatives to ‘top’, the command line utility**][1]. Some of the users asked me which one among those tools is best and on what basis (like features, contributors, years active, page requests etc.) I compared those tools. They also asked me to share the bench-marking results If I have any. Unfortunately, I didn’t even know how to benchmark programs at that time. While searching for some simple and easy to use bench-marking tools to compare the Linux programs, I stumbled upon two utilities named **‘Bench’** and **‘Hyperfine’**. These are simple and easy-to-use command line tools to benchmark Linux commands and programs on Unix-like systems. + +### 1\. Bench Tool + +The **‘Bench’** utility benchmarks one or more given commands/programs using **Haskell’s criterion** library and displays the output statistics in an easy-to-understandable format. This tool can be helpful where you need to compare similar programs based on the bench-marking result. We can also export the results to HTML format or CSV or templated output. + +#### Installing Bench Utility + +The bench utility can be installed in three methods. + +**1\. Using Linuxbrew** + +We can install Bench utility using Linuxbrew package manager. If you haven’t installed Linuxbrew yet, refer the following link. + +After installing Linuxbrew, run the following command to install Bench: + +``` +$ brew install bench +``` + +**2\. Using Haskell’s stack tool** + +First, install Haskell as described in the following link. + +And then, run the following commands to install Bench. + +``` +$ stack setup + +$ stack install bench +``` + +The ‘stack’ will install bench to **~/.local/bin** or something similar. Make sure that the installation directory is on your executable search path before using bench tool. You will be reminded to do this even if you forgot. + +**3\. Using Nix package manager** + +Another way to install Bench is using **Nix** package manager. Install Nix as shown in the below link. + +After installing Nix, install Bench tool using command: + +``` +$ nix-env -i bench +``` + +#### Benchmark Linux Commands And Programs Using Bench + +It is time to start benchmarking the programs. + +For instance, let me show you the benchmark result of ‘ls -al’ command. + +``` +$ bench 'ls -al' +``` + +**Sample output:** + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Benchmark-commands-1.png) + +You must quote the commands when you use flags/options with them. + +Similarly, you can benchmark any programs installed in your system. The following commands shows the benchmarking result of ‘htop’ and ‘ptop’ programs. + +``` +$ bench htop + +$ bench ptop +``` +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Benchmark-commands-2-1.png) +Bench tool can benchmark multiple programs at once as well. Here is the benchmarking result of ls, htop, ptop programs. + +``` +$ bench ls htop ptop +``` + +Sample output: +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Benchmark-commands-3.png) + +We can also export the benchmark result to a HTML like below. + +``` +$ bench htop --output example.html +``` + +To export the result to CSV, just run: + +``` +$ bench htop --csv FILE +``` + +View help section: + +``` +$ bench --help +``` + +### **2. Hyperfine Benchmark Tool + +** + +**Hyperfine** is yet another command line benchmarking tool inspired by the ‘Bench’ tool which we just discussed above. It is free, open source, cross-platform benchmarking program and written in **Rust** programming language. It has few additional features compared to the Bench tool as listed below. + + * Statistical analysis across multiple runs. + * Support for arbitrary shell commands. + * Constant feedback about the benchmark progress and current estimates. + * Perform warmup runs before the actual benchmark. + * Cache-clearing commands can be set up before each timing run. + * Statistical outlier detection. + * Export benchmark results to various formats, such as CSV, JSON, Markdown. + * Parameterized benchmarks. + + + +#### Installing Hyperfine + +We can install Hyperfine using any one of the following methods. + +**1\. Using Linuxbrew** + +``` +$ brew install hyperfine +``` + +**2\. Using Cargo** + +Make sure you have installed Rust as described in the following link. + +After installing Rust, run the following command to install Hyperfine via Cargo: + +``` +$ cargo install hyperfine +``` + +**3\. Using AUR helper programs** + +Hyperfine is available in [**AUR**][2]. So, you can install it on Arch-based systems using any helper programs, such as [**YaY**][3], like below. + +``` +$ yay -S hyperfine +``` + +**4\. Download and install the binaries** + +Hyperfine is available in binaries for Debian-based systems. Download the latest .deb binary file from the [**releases page**][4] and install it using ‘dpkg’ package manager. As of writing this guide, the latest version was **1.4.0**. + +``` +$ wget https://github.com/sharkdp/hyperfine/releases/download/v1.4.0/hyperfine_1.4.0_amd64.deb + +$ sudo dpkg -i hyperfine_1.4.0_amd64.deb + +$ sudo apt install -f +``` + +#### Benchmark Linux Commands And Programs Using Hyperfine + +To run a benchmark using Hyperfine, simply run it along with the program/command as shown below. + +``` +$ hyperfine 'ls -al' +``` + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/hyperfine-1.png) + +Benchmark multiple commands/programs: + +``` +$ hyperfine htop ptop +``` + +Sample output: + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/hyperfine-2.png) + +As you can see at the end of the output, Hyperfine mentiones – **‘htop ran 1.96 times faster than ptop’** , so we can immediately conclude htop performs better than Ptop. This will help you to quickly find which program performs better when benchmarking multiple programs. We don’t get this detailed output in Bench utility though. + +Hyperfine will automatically determine the number of runs to perform for each command. By default, it will perform at least **10 benchmarking runs**. If you want to set the **minimum number of runs** (E.g 5 runs), use the `-m` **/`--min-runs`** option like below: + +``` +$ hyperfine --min-runs 5 htop ptop +``` + +Or, + +``` +$ hyperfine -m 5 htop ptop +``` + +Similarly, to perform **maximum number of runs** for each command, the command would be: + +``` +$ hyperfine --max-runs 5 htop ptop +``` + +Or, + +``` +$ hyperfine -M 5 htop ptop +``` + +We can even perform **exact number of runs** for each command using the following command: + +``` +$ hyperfine -r 5 htop ptop +``` + +As you may know, if the program execution time is limited by disk I/O, the benchmarking results can be heavily influenced by disk caches and whether they are cold or warm. Luckily, Hyperfine has the options to perform a certain number of program executions before performing the actual benchmark. + +To perform NUM warmup runs (E.g 3) before the actual benchmark, use the **`-w`/**`--warmup` option like below: + +``` +$ hyperfine --warmup 3 htop +``` + +Just like Bench utility, Hyperfine also allows us to export the benchmark results to a given file. We can export the results to CSV, JSON, and Markdown formats. + +For instance, to export the results in Markdown format, use the following command: + +``` +$ hyperfine htop ptop --export-markdown +``` + +For more options and usage details, refer the help secion: + +``` +$ hyperfine --help +``` + +And, that’s all for now. If you ever be in a situation where you need to benchmark similar and alternative programs, these tools might help to compare how they performs and share the details with your peers and colleagues. + +More good stuffs to come. Stay tuned! + +Cheers! + + + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/how-to-benchmark-linux-commands-and-programs-from-commandline/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: https://www.ostechnix.com/some-alternatives-to-top-command-line-utility-you-might-want-to-know/ +[2]: https://aur.archlinux.org/packages/hyperfine +[3]: https://www.ostechnix.com/yay-found-yet-another-reliable-aur-helper/ +[4]: https://github.com/sharkdp/hyperfine/releases diff --git a/sources/tech/20181211 Winterize your Bash prompt in Linux.md b/sources/tech/20181211 Winterize your Bash prompt in Linux.md new file mode 100644 index 0000000000..bae5837a2c --- /dev/null +++ b/sources/tech/20181211 Winterize your Bash prompt in Linux.md @@ -0,0 +1,85 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Winterize your Bash prompt in Linux) +[#]: via: (https://opensource.com/article/18/12/linux-toy-bash-prompt) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Winterize your Bash prompt in Linux +====== +Your Linux terminal probably supports Unicode, so why not take advantage of that and add a seasonal touch to your prompt? +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-bash-prompt.png?itok=HK_kVn37) + +Hello once again for another installment of the Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is? Really, we're keeping it pretty open-ended: It's anything that's a fun diversion at the terminal, and we're giving bonus points for anything holiday-themed. + +Maybe you've seen some of these before, maybe you haven't. Either way, we hope you have fun. + +Today's toy is super-simple: It's your Bash prompt. Your Bash prompt? Yep! We've got a few more weeks of the holiday season left to stare at it, and even more weeks of winter here in the northern hemisphere, so why not have some fun with it. + +Your Bash prompt currently might be a simple dollar sign ( **$** ), or more likely, it's something a little longer. If you're not sure what makes up your Bash prompt right now, you can find it in an environment variable called $PS1. To see it, type: + +``` +echo $PS1 +``` + +For me, this returns: + +``` +[\u@\h \W]\$ +``` + +The **\u** , **\h** , and **\W** are special characters for username, hostname, and working directory. There are others you can use as well; for help building out your Bash prompt, you can use [EzPrompt][1], an online generator of PS1 configurations that includes lots of options including date and time, Git status, and more. + +You may have other variables that make up your Bash prompt set as well; **$PS2** for me contains the closing brace of my command prompt. See [this article][2] for more information. + +To change your prompt, simply set the environment variable in your terminal like this: + +``` +$ PS1='\u is cold: ' +jehb is cold: +``` + +To set it permanently, add the same code to your **/etc/bashrc **using your favorite text editor. + +So what does this have to do with winterization? Well, chances are on a modern machine, your terminal support Unicode, so you're not limited to the standard ASCII character set. You can use any emoji that's a part of the Unicode specification, including a snowflake ❄, a snowman ☃, or a pair of skis 🎿. You've got plenty of wintery options to choose from. + +``` +🎄 Christmas Tree +🧥 Coat +🦌 Deer +🧤 Gloves +🤶 Mrs. Claus +🎅 Santa Claus +🧣 Scarf +🎿 Skis +🏂 Snowboarder +❄ Snowflake +☃ Snowman +⛄ Snowman Without Snow +🎁 Wrapped Gift +``` + +Pick your favorite, and enjoy some winter cheer. Fun fact: modern filesystems also support Unicode characters in their filenames, meaning you can technically name your next program **"❄❄❄❄❄.py"**. That said, please don't. + +Do you have a favorite command-line toy that you think I ought to include? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [Snake your way across your Linux terminal][3], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-bash-prompt + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: http://ezprompt.net/ +[2]: https://access.redhat.com/solutions/505983 +[3]: https://opensource.com/article/18/12/linux-toy-snake diff --git a/sources/tech/20181212 TLP - An Advanced Power Management Tool That Improve Battery Life On Linux Laptop.md b/sources/tech/20181212 TLP - An Advanced Power Management Tool That Improve Battery Life On Linux Laptop.md new file mode 100644 index 0000000000..e1e6a7f25e --- /dev/null +++ b/sources/tech/20181212 TLP - An Advanced Power Management Tool That Improve Battery Life On Linux Laptop.md @@ -0,0 +1,745 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (TLP – An Advanced Power Management Tool That Improve Battery Life On Linux Laptop) +[#]: via: (https://www.2daygeek.com/tlp-increase-optimize-linux-laptop-battery-life/) +[#]: author: (Magesh Maruthamuthu https://www.2daygeek.com/author/magesh/) + +TLP – An Advanced Power Management Tool That Improve Battery Life On Linux Laptop +====== + +Laptop battery is highly optimized for Windows OS, that i had realized when i was using Windows OS in my laptop but it’s not same for Linux. + +Over the years Linux has improved a lot for battery optimization but still we need make some necessary things to improve laptop battery life in Linux. + +When i think about battery life, i got few options for that but i felt TLP is a better solutions for me so, i’m going with it. + +In this tutorial we are going to discuss about TLP in details to improve battery life. + +We had written three articles previously in our site about **[laptop battery saving utilities][1]** for Linux **[PowerTOP][2]** and **[Battery Charging State][3]**. + +### What is TLP? + +[TLP][4] is a free opensource advanced power management tool that improve your battery life without making any configuration change. + +Since it comes with a default configuration already optimized for battery life, so you may just install and forget it. + +Also, it is highly customizable to fulfill your specific requirements. TLP is a pure command line tool with automated background tasks. It does not contain a GUI. + +TLP runs on every laptop brand. Setting the battery charge thresholds is available for IBM/Lenovo ThinkPads only. + +All TLP settings are stored in `/etc/default/tlp`. The default configuration provides optimized power saving out of the box. + +The following TLP settings is available for customization and you need to make the necessary changes accordingly if you want it. + +### TLP Features + + * Kernel laptop mode and dirty buffer timeouts + * Processor frequency scaling including “turbo boost” / “turbo core” + * Limit max/min P-state to control power dissipation of the CPU + * HWP energy performance hints + * Power aware process scheduler for multi-core/hyper-threading + * Processor performance versus energy savings policy (x86_energy_perf_policy) + * Hard disk advanced power magement level (APM) and spin down timeout (per disk) + * AHCI link power management (ALPM) with device blacklist + * PCIe active state power management (PCIe ASPM) + * Runtime power management for PCI(e) bus devices + * Radeon graphics power management (KMS and DPM) + * Wifi power saving mode + * Power off optical drive in drive bay + * Audio power saving mode + * I/O scheduler (per disk) + * USB autosuspend with device blacklist/whitelist (input devices excluded automatically) + * Enable or disable integrated wifi, bluetooth or wwan devices upon system startup and shutdown + * Restore radio device state on system startup (from previous shutdown). + * Radio device wizard: switch radios upon network connect/disconnect and dock/undock + * Disable Wake On LAN + * Integrated WWAN and bluetooth state is restored after suspend/hibernate + * Untervolting of Intel processors – requires kernel with PHC-Patch + * Battery charge thresholds – ThinkPads only + * Recalibrate battery – ThinkPads only + + + +### How to Install TLP in Linux + +TLP package is available in most of the distributions official repository so, use the distributions **[Package Manager][5]** to install it. + +For **`Fedora`** system, use **[DNF Command][6]** to install TLP. + +``` +$ sudo dnf install tlp tlp-rdw +``` + +ThinkPads require an additional packages. + +``` +$ sudo dnf install https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm +$ sudo dnf install http://repo.linrunner.de/fedora/tlp/repos/releases/tlp-release.fc$(rpm -E %fedora).noarch.rpm +$ sudo dnf install akmod-tp_smapi akmod-acpi_call kernel-devel +``` + +Install smartmontool to display S.M.A.R.T. data in tlp-stat. + +``` +$ sudo dnf install smartmontools +``` + +For **`Debian/Ubuntu`** systems, use **[APT-GET Command][7]** or **[APT Command][8]** to install TLP. + +``` +$ sudo apt install tlp tlp-rdw +``` + +ThinkPads require an additional packages. + +``` +$ sudo apt-get install tp-smapi-dkms acpi-call-dkms +``` + +Install smartmontool to display S.M.A.R.T. data in tlp-stat. + +``` +$ sudo apt-get install smartmontools +``` + +When the official package becomes outdated for Ubuntu based systems then use the following PPA repository which provides an up-to-date version. Run the following commands to install TLP using the PPA. + +``` +$ sudo apt-get install tlp tlp-rdw +``` + +For **`Arch Linux`** based systems, use **[Pacman Command][9]** to install TLP. + +``` +$ sudo pacman -S tlp tlp-rdw +``` + +ThinkPads require an additional packages. + +``` +$ pacman -S tp_smapi acpi_call +``` + +Install smartmontool to display S.M.A.R.T. data in tlp-stat. + +``` +$ sudo pacman -S smartmontools +``` + +Enable TLP & TLP-Sleep service on boot for Arch Linux based systems. + +``` +$ sudo systemctl enable tlp.service +$ sudo systemctl enable tlp-sleep.service +``` + +You should also mask the following services to avoid conflicts and assure proper operation of TLP’s radio device switching options for Arch Linux based systems. + +``` +$ sudo systemctl mask systemd-rfkill.service +$ sudo systemctl mask systemd-rfkill.socket +``` + +For **`RHEL/CentOS`** systems, use **[YUM Command][10]** to install TLP. + +``` +$ sudo yum install tlp tlp-rdw +``` + +Install smartmontool to display S.M.A.R.T. data in tlp-stat. + +``` +$ sudo yum install smartmontools +``` + +For **`openSUSE Leap`** system, use **[Zypper Command][11]** to install TLP. + +``` +$ sudo zypper install TLP +``` + +Install smartmontool to display S.M.A.R.T. data in tlp-stat. + +``` +$ sudo zypper install smartmontools +``` + +After successfully TLP installed, use the following command to start the service. + +``` +$ systemctl start tlp.service +``` + +To show battery information. + +``` +$ sudo tlp-stat -b +or +$ sudo tlp-stat --battery + +--- TLP 1.1 -------------------------------------------- + ++++ Battery Status +/sys/class/power_supply/BAT0/manufacturer = SMP +/sys/class/power_supply/BAT0/model_name = L14M4P23 +/sys/class/power_supply/BAT0/cycle_count = (not supported) +/sys/class/power_supply/BAT0/energy_full_design = 60000 [mWh] +/sys/class/power_supply/BAT0/energy_full = 48850 [mWh] +/sys/class/power_supply/BAT0/energy_now = 48850 [mWh] +/sys/class/power_supply/BAT0/power_now = 0 [mW] +/sys/class/power_supply/BAT0/status = Full + +Charge = 100.0 [%] +Capacity = 81.4 [%] +``` + +To show disk information. + +``` +$ sudo tlp-stat -d +or +$ sudo tlp-stat --disk + +--- TLP 1.1 -------------------------------------------- + ++++ Storage Devices +/dev/sda: + Model = WDC WD10SPCX-24HWST1 + Firmware = 02.01A02 + APM Level = 128 + Status = active/idle + Scheduler = mq-deadline + + Runtime PM: control = on, autosuspend_delay = (not available) + + SMART info: + 4 Start_Stop_Count = 18787 + 5 Reallocated_Sector_Ct = 0 + 9 Power_On_Hours = 606 [h] + 12 Power_Cycle_Count = 1792 + 193 Load_Cycle_Count = 25775 + 194 Temperature_Celsius = 31 [°C] + + ++++ AHCI Link Power Management (ALPM) +/sys/class/scsi_host/host0/link_power_management_policy = med_power_with_dipm +/sys/class/scsi_host/host1/link_power_management_policy = med_power_with_dipm +/sys/class/scsi_host/host2/link_power_management_policy = med_power_with_dipm +/sys/class/scsi_host/host3/link_power_management_policy = med_power_with_dipm + ++++ AHCI Host Controller Runtime Power Management +/sys/bus/pci/devices/0000:00:17.0/ata1/power/control = on +/sys/bus/pci/devices/0000:00:17.0/ata2/power/control = on +/sys/bus/pci/devices/0000:00:17.0/ata3/power/control = on +/sys/bus/pci/devices/0000:00:17.0/ata4/power/control = on +``` + +To show PCI device information. + +``` +$ sudo tlp-stat -e +or +$ sudo tlp-stat --pcie + +--- TLP 1.1 -------------------------------------------- + ++++ Runtime Power Management +Device blacklist = (not configured) +Driver blacklist = amdgpu nouveau nvidia radeon pcieport + +/sys/bus/pci/devices/0000:00:00.0/power/control = auto (0x060000, Host bridge, skl_uncore) +/sys/bus/pci/devices/0000:00:01.0/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:02.0/power/control = auto (0x030000, VGA compatible controller, i915) +/sys/bus/pci/devices/0000:00:14.0/power/control = auto (0x0c0330, USB controller, xhci_hcd) +/sys/bus/pci/devices/0000:00:16.0/power/control = auto (0x078000, Communication controller, mei_me) +/sys/bus/pci/devices/0000:00:17.0/power/control = auto (0x010601, SATA controller, ahci) +/sys/bus/pci/devices/0000:00:1c.0/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1c.2/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1c.3/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1d.0/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1f.0/power/control = auto (0x060100, ISA bridge, no driver) +/sys/bus/pci/devices/0000:00:1f.2/power/control = auto (0x058000, Memory controller, no driver) +/sys/bus/pci/devices/0000:00:1f.3/power/control = auto (0x040300, Audio device, snd_hda_intel) +/sys/bus/pci/devices/0000:00:1f.4/power/control = auto (0x0c0500, SMBus, i801_smbus) +/sys/bus/pci/devices/0000:01:00.0/power/control = auto (0x030200, 3D controller, nouveau) +/sys/bus/pci/devices/0000:07:00.0/power/control = auto (0x080501, SD Host controller, sdhci-pci) +/sys/bus/pci/devices/0000:08:00.0/power/control = auto (0x028000, Network controller, iwlwifi) +/sys/bus/pci/devices/0000:09:00.0/power/control = auto (0x020000, Ethernet controller, r8168) +/sys/bus/pci/devices/0000:0a:00.0/power/control = auto (0x010802, Non-Volatile memory controller, nvme) +``` + +To show graphics card information. + +``` +$ sudo tlp-stat -g +or +$ sudo tlp-stat --graphics + +--- TLP 1.1 -------------------------------------------- + ++++ Intel Graphics +/sys/module/i915/parameters/enable_dc = -1 (use per-chip default) +/sys/module/i915/parameters/enable_fbc = 1 (enabled) +/sys/module/i915/parameters/enable_psr = 0 (disabled) +/sys/module/i915/parameters/modeset = -1 (use per-chip default) +``` + +To show Processor information. + +``` +$ sudo tlp-stat -p +or +$ sudo tlp-stat --processor + +--- TLP 1.1 -------------------------------------------- + ++++ Processor +CPU model = Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz + +/sys/devices/system/cpu/cpu0/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu0/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu1/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu1/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu1/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu1/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu1/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu2/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu2/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu2/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu2/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu2/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu2/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu2/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu3/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu3/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu3/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu3/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu3/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu3/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu3/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu4/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu4/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu4/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu4/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu4/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu4/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu4/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu5/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu5/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu5/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu5/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu5/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu5/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu5/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu6/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu6/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu6/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu6/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu6/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu6/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu6/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu7/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu7/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu7/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu7/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu7/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu7/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu7/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/intel_pstate/min_perf_pct = 22 [%] +/sys/devices/system/cpu/intel_pstate/max_perf_pct = 100 [%] +/sys/devices/system/cpu/intel_pstate/no_turbo = 0 +/sys/devices/system/cpu/intel_pstate/turbo_pct = 33 [%] +/sys/devices/system/cpu/intel_pstate/num_pstates = 28 + +x86_energy_perf_policy: program not installed. + +/sys/module/workqueue/parameters/power_efficient = Y +/proc/sys/kernel/nmi_watchdog = 0 + ++++ Undervolting +PHC kernel not available. +``` + +To show system data information. + +``` +$ sudo tlp-stat -s +or +$ sudo tlp-stat --system + +--- TLP 1.1 -------------------------------------------- + ++++ System Info +System = LENOVO Lenovo ideapad Y700-15ISK 80NV +BIOS = CDCN35WW +Release = "Manjaro Linux" +Kernel = 4.19.6-1-MANJARO #1 SMP PREEMPT Sat Dec 1 12:21:26 UTC 2018 x86_64 +/proc/cmdline = BOOT_IMAGE=/boot/vmlinuz-4.19-x86_64 root=UUID=69d9dd18-36be-4631-9ebb-78f05fe3217f rw quiet resume=UUID=a2092b92-af29-4760-8e68-7a201922573b +Init system = systemd +Boot mode = BIOS (CSM, Legacy) + ++++ TLP Status +State = enabled +Last run = 11:04:00 IST, 596 sec(s) ago +Mode = battery +Power source = battery +``` + +To show temperatures and fan speed information. + +``` +$ sudo tlp-stat -t +or +$ sudo tlp-stat --temp + +--- TLP 1.1 -------------------------------------------- + ++++ Temperatures +CPU temp = 36 [°C] +Fan speed = (not available) +``` + +To show USB device data information. + +``` +$ sudo tlp-stat -u +or +$ sudo tlp-stat --usb + +--- TLP 1.1 -------------------------------------------- + ++++ USB +Autosuspend = disabled +Device whitelist = (not configured) +Device blacklist = (not configured) +Bluetooth blacklist = disabled +Phone blacklist = disabled +WWAN blacklist = enabled + +Bus 002 Device 001 ID 1d6b:0003 control = auto, autosuspend_delay_ms = 0 -- Linux Foundation 3.0 root hub (hub) +Bus 001 Device 003 ID 174f:14e8 control = auto, autosuspend_delay_ms = 2000 -- Syntek (uvcvideo) +Bus 001 Device 002 ID 17ef:6053 control = on, autosuspend_delay_ms = 2000 -- Lenovo (usbhid) +Bus 001 Device 004 ID 8087:0a2b control = auto, autosuspend_delay_ms = 2000 -- Intel Corp. (btusb) +Bus 001 Device 001 ID 1d6b:0002 control = auto, autosuspend_delay_ms = 0 -- Linux Foundation 2.0 root hub (hub) +``` + +To show warnings. + +``` +$ sudo tlp-stat -w +or +$ sudo tlp-stat --warn + +--- TLP 1.1 -------------------------------------------- + +No warnings detected. +``` + +Status report with configuration and all active settings. + +``` +$ sudo tlp-stat + +--- TLP 1.1 -------------------------------------------- + ++++ Configured Settings: /etc/default/tlp +TLP_ENABLE=1 +TLP_DEFAULT_MODE=AC +TLP_PERSISTENT_DEFAULT=0 +DISK_IDLE_SECS_ON_AC=0 +DISK_IDLE_SECS_ON_BAT=2 +MAX_LOST_WORK_SECS_ON_AC=15 +MAX_LOST_WORK_SECS_ON_BAT=60 +CPU_HWP_ON_AC=balance_performance +CPU_HWP_ON_BAT=balance_power +SCHED_POWERSAVE_ON_AC=0 +SCHED_POWERSAVE_ON_BAT=1 +NMI_WATCHDOG=0 +ENERGY_PERF_POLICY_ON_AC=performance +ENERGY_PERF_POLICY_ON_BAT=power +DISK_DEVICES="sda sdb" +DISK_APM_LEVEL_ON_AC="254 254" +DISK_APM_LEVEL_ON_BAT="128 128" +SATA_LINKPWR_ON_AC="med_power_with_dipm max_performance" +SATA_LINKPWR_ON_BAT="med_power_with_dipm max_performance" +AHCI_RUNTIME_PM_TIMEOUT=15 +PCIE_ASPM_ON_AC=performance +PCIE_ASPM_ON_BAT=powersave +RADEON_POWER_PROFILE_ON_AC=default +RADEON_POWER_PROFILE_ON_BAT=low +RADEON_DPM_STATE_ON_AC=performance +RADEON_DPM_STATE_ON_BAT=battery +RADEON_DPM_PERF_LEVEL_ON_AC=auto +RADEON_DPM_PERF_LEVEL_ON_BAT=auto +WIFI_PWR_ON_AC=off +WIFI_PWR_ON_BAT=on +WOL_DISABLE=Y +SOUND_POWER_SAVE_ON_AC=0 +SOUND_POWER_SAVE_ON_BAT=1 +SOUND_POWER_SAVE_CONTROLLER=Y +BAY_POWEROFF_ON_AC=0 +BAY_POWEROFF_ON_BAT=0 +BAY_DEVICE="sr0" +RUNTIME_PM_ON_AC=on +RUNTIME_PM_ON_BAT=auto +RUNTIME_PM_DRIVER_BLACKLIST="amdgpu nouveau nvidia radeon pcieport" +USB_AUTOSUSPEND=0 +USB_BLACKLIST_BTUSB=0 +USB_BLACKLIST_PHONE=0 +USB_BLACKLIST_PRINTER=1 +USB_BLACKLIST_WWAN=1 +RESTORE_DEVICE_STATE_ON_STARTUP=0 + ++++ System Info +System = LENOVO Lenovo ideapad Y700-15ISK 80NV +BIOS = CDCN35WW +Release = "Manjaro Linux" +Kernel = 4.19.6-1-MANJARO #1 SMP PREEMPT Sat Dec 1 12:21:26 UTC 2018 x86_64 +/proc/cmdline = BOOT_IMAGE=/boot/vmlinuz-4.19-x86_64 root=UUID=69d9dd18-36be-4631-9ebb-78f05fe3217f rw quiet resume=UUID=a2092b92-af29-4760-8e68-7a201922573b +Init system = systemd +Boot mode = BIOS (CSM, Legacy) + ++++ TLP Status +State = enabled +Last run = 11:04:00 IST, 684 sec(s) ago +Mode = battery +Power source = battery + ++++ Processor +CPU model = Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz + +/sys/devices/system/cpu/cpu0/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu0/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu1/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu1/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu1/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu1/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu1/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu2/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu2/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu2/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu2/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu2/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu2/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu2/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu3/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu3/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu3/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu3/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu3/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu3/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu3/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu4/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu4/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu4/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu4/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu4/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu4/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu4/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu5/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu5/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu5/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu5/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu5/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu5/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu5/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu6/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu6/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu6/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu6/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu6/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu6/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu6/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/cpu7/cpufreq/scaling_driver = intel_pstate +/sys/devices/system/cpu/cpu7/cpufreq/scaling_governor = powersave +/sys/devices/system/cpu/cpu7/cpufreq/scaling_available_governors = performance powersave +/sys/devices/system/cpu/cpu7/cpufreq/scaling_min_freq = 800000 [kHz] +/sys/devices/system/cpu/cpu7/cpufreq/scaling_max_freq = 3500000 [kHz] +/sys/devices/system/cpu/cpu7/cpufreq/energy_performance_preference = balance_power +/sys/devices/system/cpu/cpu7/cpufreq/energy_performance_available_preferences = default performance balance_performance balance_power power + +/sys/devices/system/cpu/intel_pstate/min_perf_pct = 22 [%] +/sys/devices/system/cpu/intel_pstate/max_perf_pct = 100 [%] +/sys/devices/system/cpu/intel_pstate/no_turbo = 0 +/sys/devices/system/cpu/intel_pstate/turbo_pct = 33 [%] +/sys/devices/system/cpu/intel_pstate/num_pstates = 28 + +x86_energy_perf_policy: program not installed. + +/sys/module/workqueue/parameters/power_efficient = Y +/proc/sys/kernel/nmi_watchdog = 0 + ++++ Undervolting +PHC kernel not available. + ++++ Temperatures +CPU temp = 42 [°C] +Fan speed = (not available) + ++++ File System +/proc/sys/vm/laptop_mode = 2 +/proc/sys/vm/dirty_writeback_centisecs = 6000 +/proc/sys/vm/dirty_expire_centisecs = 6000 +/proc/sys/vm/dirty_ratio = 20 +/proc/sys/vm/dirty_background_ratio = 10 + ++++ Storage Devices +/dev/sda: + Model = WDC WD10SPCX-24HWST1 + Firmware = 02.01A02 + APM Level = 128 + Status = active/idle + Scheduler = mq-deadline + + Runtime PM: control = on, autosuspend_delay = (not available) + + SMART info: + 4 Start_Stop_Count = 18787 + 5 Reallocated_Sector_Ct = 0 + 9 Power_On_Hours = 606 [h] + 12 Power_Cycle_Count = 1792 + 193 Load_Cycle_Count = 25777 + 194 Temperature_Celsius = 31 [°C] + + ++++ AHCI Link Power Management (ALPM) +/sys/class/scsi_host/host0/link_power_management_policy = med_power_with_dipm +/sys/class/scsi_host/host1/link_power_management_policy = med_power_with_dipm +/sys/class/scsi_host/host2/link_power_management_policy = med_power_with_dipm +/sys/class/scsi_host/host3/link_power_management_policy = med_power_with_dipm + ++++ AHCI Host Controller Runtime Power Management +/sys/bus/pci/devices/0000:00:17.0/ata1/power/control = on +/sys/bus/pci/devices/0000:00:17.0/ata2/power/control = on +/sys/bus/pci/devices/0000:00:17.0/ata3/power/control = on +/sys/bus/pci/devices/0000:00:17.0/ata4/power/control = on + ++++ PCIe Active State Power Management +/sys/module/pcie_aspm/parameters/policy = powersave + ++++ Intel Graphics +/sys/module/i915/parameters/enable_dc = -1 (use per-chip default) +/sys/module/i915/parameters/enable_fbc = 1 (enabled) +/sys/module/i915/parameters/enable_psr = 0 (disabled) +/sys/module/i915/parameters/modeset = -1 (use per-chip default) + ++++ Wireless +bluetooth = on +wifi = on +wwan = none (no device) + +hci0(btusb) : bluetooth, not connected +wlp8s0(iwlwifi) : wifi, connected, power management = on + ++++ Audio +/sys/module/snd_hda_intel/parameters/power_save = 1 +/sys/module/snd_hda_intel/parameters/power_save_controller = Y + ++++ Runtime Power Management +Device blacklist = (not configured) +Driver blacklist = amdgpu nouveau nvidia radeon pcieport + +/sys/bus/pci/devices/0000:00:00.0/power/control = auto (0x060000, Host bridge, skl_uncore) +/sys/bus/pci/devices/0000:00:01.0/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:02.0/power/control = auto (0x030000, VGA compatible controller, i915) +/sys/bus/pci/devices/0000:00:14.0/power/control = auto (0x0c0330, USB controller, xhci_hcd) +/sys/bus/pci/devices/0000:00:16.0/power/control = auto (0x078000, Communication controller, mei_me) +/sys/bus/pci/devices/0000:00:17.0/power/control = auto (0x010601, SATA controller, ahci) +/sys/bus/pci/devices/0000:00:1c.0/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1c.2/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1c.3/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1d.0/power/control = auto (0x060400, PCI bridge, pcieport) +/sys/bus/pci/devices/0000:00:1f.0/power/control = auto (0x060100, ISA bridge, no driver) +/sys/bus/pci/devices/0000:00:1f.2/power/control = auto (0x058000, Memory controller, no driver) +/sys/bus/pci/devices/0000:00:1f.3/power/control = auto (0x040300, Audio device, snd_hda_intel) +/sys/bus/pci/devices/0000:00:1f.4/power/control = auto (0x0c0500, SMBus, i801_smbus) +/sys/bus/pci/devices/0000:01:00.0/power/control = auto (0x030200, 3D controller, nouveau) +/sys/bus/pci/devices/0000:07:00.0/power/control = auto (0x080501, SD Host controller, sdhci-pci) +/sys/bus/pci/devices/0000:08:00.0/power/control = auto (0x028000, Network controller, iwlwifi) +/sys/bus/pci/devices/0000:09:00.0/power/control = auto (0x020000, Ethernet controller, r8168) +/sys/bus/pci/devices/0000:0a:00.0/power/control = auto (0x010802, Non-Volatile memory controller, nvme) + ++++ USB +Autosuspend = disabled +Device whitelist = (not configured) +Device blacklist = (not configured) +Bluetooth blacklist = disabled +Phone blacklist = disabled +WWAN blacklist = enabled + +Bus 002 Device 001 ID 1d6b:0003 control = auto, autosuspend_delay_ms = 0 -- Linux Foundation 3.0 root hub (hub) +Bus 001 Device 003 ID 174f:14e8 control = auto, autosuspend_delay_ms = 2000 -- Syntek (uvcvideo) +Bus 001 Device 002 ID 17ef:6053 control = on, autosuspend_delay_ms = 2000 -- Lenovo (usbhid) +Bus 001 Device 004 ID 8087:0a2b control = auto, autosuspend_delay_ms = 2000 -- Intel Corp. (btusb) +Bus 001 Device 001 ID 1d6b:0002 control = auto, autosuspend_delay_ms = 0 -- Linux Foundation 2.0 root hub (hub) + ++++ Battery Status +/sys/class/power_supply/BAT0/manufacturer = SMP +/sys/class/power_supply/BAT0/model_name = L14M4P23 +/sys/class/power_supply/BAT0/cycle_count = (not supported) +/sys/class/power_supply/BAT0/energy_full_design = 60000 [mWh] +/sys/class/power_supply/BAT0/energy_full = 51690 [mWh] +/sys/class/power_supply/BAT0/energy_now = 50140 [mWh] +/sys/class/power_supply/BAT0/power_now = 12185 [mW] +/sys/class/power_supply/BAT0/status = Discharging + +Charge = 97.0 [%] +Capacity = 86.2 [%] +``` + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/tlp-increase-optimize-linux-laptop-battery-life/ + +作者：[Magesh Maruthamuthu][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/magesh/ +[b]: https://github.com/lujun9972 +[1]: https://www.2daygeek.com/check-laptop-battery-status-and-charging-state-in-linux-terminal/ +[2]: https://www.2daygeek.com/powertop-monitors-laptop-battery-usage-linux/ +[3]: https://www.2daygeek.com/monitor-laptop-battery-charging-state-linux/ +[4]: https://linrunner.de/en/tlp/docs/tlp-linux-advanced-power-management.html +[5]: https://www.2daygeek.com/category/package-management/ +[6]: https://www.2daygeek.com/dnf-command-examples-manage-packages-fedora-system/ +[7]: https://www.2daygeek.com/apt-get-apt-cache-command-examples-manage-packages-debian-ubuntu-systems/ +[8]: https://www.2daygeek.com/apt-command-examples-manage-packages-debian-ubuntu-systems/ +[9]: https://www.2daygeek.com/pacman-command-examples-manage-packages-arch-linux-system/ +[10]: https://www.2daygeek.com/yum-command-examples-manage-packages-rhel-centos-systems/ +[11]: https://www.2daygeek.com/zypper-command-examples-manage-packages-opensuse-system/ diff --git a/sources/tech/20181212 Top 5 configuration management tools.md b/sources/tech/20181212 Top 5 configuration management tools.md new file mode 100644 index 0000000000..72aebb209a --- /dev/null +++ b/sources/tech/20181212 Top 5 configuration management tools.md @@ -0,0 +1,122 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Top 5 configuration management tools) +[#]: via: (https://opensource.com/article/18/12/configuration-management-tools) +[#]: author: (Marco Bravo https://opensource.com/users/marcobravo) + +Top 5 configuration management tools +====== +Learn about configuration management tools and figure out which will work best for your DevOps organization. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/innovation_lightbulb_gears_devops_ansible.png?itok=TSbmp3_M) + +DevOps is evolving and gaining traction as organizations discover how it enables them to produce better applications and reduce their software products' time to market. + +[DevOps' core values][1] are Culture, Automation, Measurement, and Sharing (CAMS), and an organization's adherence to them influences how successful it is. + + * **Culture** brings people and processes together; + * **Automation** creates a fabric for DevOps; + * **Measurement** permits improvements; and + * **Sharing** enables the feedback loop in the CAMS cycle. + + + +Another DevOps concept is the idea that almost everything can be managed in code: servers, databases, networks, log files, application configurations, documentation, automated tests, deployment processes, and more. + +In this article, I'll focus on one aspect of automation: Configuration management. As part of [Infrastructure as Code][2] (IaC), configuration management tools enable the use of tested and proven software development practices for managing and provisioning data centers through plaintext definition files. + +By manipulating simple configuration files, a DevOps team can use application development best practices, such as version control, testing, small deployments, and design patterns. In short, this means code can be written to provision and manage an infrastructure as well as automate processes. + +### Why use configuration management tools? + +Configuration management tools enable changes and deployments to be faster, repeatable, scalable, predictable, and able to maintain the desired state, which brings controlled assets into an expected state. + +Some advantages of using configuration management tools include: + + * Adherence to coding conventions that make it easier to navigate code + * Idempotency, which means that the end state remains the same, no matter how many times the code is executed + * Distribution design to improve managing large numbers of remote servers + + + +Some configuration management tools use a pull model, in which an agent installed on the servers runs periodically to pull the latest definitions from a central repository and apply them to the server. Other tools use a push model, where a central server triggers updates to managed servers. + +### Top 5 configuration management tools + +There are a variety of configuration management tools available, and each has specific features that make it better for some situations than others. Yet the top five configuration management tools, presented below in alphabetical order, have several things in common that I believe are essential for DevOps success: all have an open source license, use externalized configuration definition files, run unattended, and are scriptable. All of the descriptions are based on information from the tools' software repositories and websites. + +#### Ansible + +"Ansible is a radically simple IT automation platform that makes your applications and systems easier to deploy. Avoid writing scripts or custom code to deploy and update your applications—automate in a language that approaches plain English, using SSH, with no agents to install on remote systems." —[GitHub repository][3] + +Ansible is one of my favorite tools; I started using it several years ago and fell in love with it. You can use Ansible to execute the same command for a list of servers from the command line. You can also use it to automate tasks using "playbooks" written into a YAML file, which facilitate communication between teams and non-technical people. Its main advantages are that it is simple, agentless, and easy to read (especially for non-programmers). + +Because agents are not required, there is less overhead on servers. An SSH connection is necessary when running in push mode (which is the default), but pull mode is available if needed. [Playbooks][4] can be written with a minimal set of commands or they can be scaled for more elaborate automation tasks that could include roles, variables, and modules written by other people. + +You can combine Ansible with other tools to create a central console to control processes. Those tools include Ansible Works (AWX), Jenkins, RunDeck, and [ARA][5], which offers [traceability when running playbooks][6]. + +### CFEngine + +"CFEngine 3 is a popular open source configuration management system. Its primary function is to provide automated configuration and maintenance of large-scale computer systems." —[GitHub repository][7] + +CFEngine was introduced by Mark Burgess in 1993 as a scientific approach to automated configuration management. The goal was to deal with the entropy in computer systems' configuration and resolve it with end-state "convergence." Convergence means a desired end-state and elaborates on idempotence as a capacity to reach the desired end-state. Burgess' research evolved in 2004 when he proposed the [Promise theory][8] as a model of voluntary cooperation between agents. + +The current version of CFEngine incorporates Promise theory and uses agents running on each server that pull the configuration from a central repository. It requires some expert knowledge to deal with configurations, so it's best suited for technical people. + +### Chef + +"A systems integration framework, built to bring the benefits of configuration management to your entire infrastructure." —[GitHub repository][9] + +Chef uses "recipes" written in Ruby to keep your infrastructure running up-to-date and compliant. The recipes describe a series of resources that should be in a particular state. Chef can run in client/server mode or in a standalone configuration named [chef-solo][10]. It has good integration with the major cloud providers to automatically provision and configure new machines. + +Chef has a solid user base and provides a full toolset to allow people with different technical backgrounds and skills to interact around the recipes. But, at its base, it is more technically oriented tool. + +### Puppet + +"Puppet, an automated administrative engine for your Linux, Unix, and Windows systems, performs administrative tasks (such as adding users, installing packages, and updating server configurations) based on a centralized specification." —[GitHub repository][11] + +Conceived as a tool oriented toward operations and sysadmins, Puppet has consolidated as a configuration management tool. It usually works in a client-server architecture, and an agent communicates with the server to fetch configuration instructions. + +Puppet uses a declarative language or Ruby to describe the system configuration. It is organized in modules, and manifest files contain the desired-state goals to keep everything as required. Puppet uses the push model by default, and the pull model can be configured. + +### Salt + +"Software to automate the management and configuration of any infrastructure or application at scale." — [GitHub repository][12] + +Salt was created for high-speed data collection and scale beyond tens of thousands of servers. It uses Python modules to handle configuration details and specific actions. These modules manage all of Salt's remote execution and state management behavior. Some level of technical skills are required to configure the modules. + +Salt uses a client-server topology (with the Salt master as server and Salt minions as clients). Configurations are kept in Salt state files, which describe everything required to keep a system in the desired state. + +### Conclusion + +The landscape of DevOps tools is evolving all the time, and it is important to keep an eye on the changes. I hope this article will encourage you to explore these concepts and tools further. If so, the Cloud Native Computing Foundation (CNCF) maintains a good reference in the [Cloud Native Landscape Project][13]. + + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/configuration-management-tools + +作者：[Marco Bravo][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/marcobravo +[b]: https://github.com/lujun9972 +[1]: https://www.oreilly.com/learning/why-use-terraform +[2]: https://www.oreilly.com/library/view/infrastructure-as-code/9781491924334/ch04.html +[3]: https://github.com/ansible/ansible +[4]: https://opensource.com/article/18/8/ansible-playbooks-you-should-try +[5]: https://github.com/openstack/ara +[6]: https://opensource.com/article/18/5/analyzing-ansible-runs-using-ara +[7]: https://github.com/cfengine/core +[8]: https://en.wikipedia.org/wiki/Promise_theory +[9]: https://github.com/chef/chef +[10]: https://docs.chef.io/chef_solo.html +[11]: https://github.com/puppetlabs/puppet +[12]: https://github.com/saltstack/salt +[13]: https://github.com/cncf/landscape diff --git a/sources/tech/20181213 Podman and user namespaces- A marriage made in heaven.md b/sources/tech/20181213 Podman and user namespaces- A marriage made in heaven.md new file mode 100644 index 0000000000..adc14c6111 --- /dev/null +++ b/sources/tech/20181213 Podman and user namespaces- A marriage made in heaven.md @@ -0,0 +1,145 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Podman and user namespaces: A marriage made in heaven) +[#]: via: (https://opensource.com/article/18/12/podman-and-user-namespaces) +[#]: author: (Daniel J Walsh https://opensource.com/users/rhatdan) + +Podman and user namespaces: A marriage made in heaven +====== +Learn how to use Podman to run containers in separate user namespaces. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/architecture_structure_planning_design_.png?itok=KL7dIDct) + +[Podman][1], part of the [libpod][2] library, enables users to manage pods, containers, and container images. In my last article, I wrote about [Podman as a more secure way to run containers][3]. Here, I'll explain how to use Podman to run containers in separate user namespaces. + +I have always thought of [user namespace][4], primarily developed by Red Hat's Eric Biederman, as a great feature for separating containers. User namespace allows you to specify a user identifier (UID) and group identifier (GID) mapping to run your containers. This means you can run as UID 0 inside the container and UID 100000 outside the container. If your container processes escape the container, the kernel will treat them as UID 100000. Not only that, but any file object owned by a UID that isn't mapped into the user namespace will be treated as owned by "nobody" (65534, kernel.overflowuid), and the container process will not be allowed access unless the object is accessible by "other" (world readable/writable). + +If you have a file owned by "real" root with permissions [660][5], and the container processes in the user namespace attempt to read it, they will be prevented from accessing it and will see the file as owned by nobody. + +### An example + +Here's how that might work. First, I create a file in my system owned by root. + +``` +$ sudo bash -c "echo Test > /tmp/test" +$ sudo chmod 600 /tmp/test +$ sudo ls -l /tmp/test +-rw-------. 1 root root 5 Dec 17 16:40 /tmp/test +``` + +Next, I volume-mount the file into a container running with a user namespace map 0:100000:5000. + +``` +$ sudo podman run -ti -v /tmp/test:/tmp/test:Z --uidmap 0:100000:5000 fedora sh +# id +uid=0(root) gid=0(root) groups=0(root) +# ls -l /tmp/test +-rw-rw----. 1 nobody nobody 8 Nov 30 12:40 /tmp/test +# cat /tmp/test +cat: /tmp/test: Permission denied +``` + +The **\--uidmap** setting above tells Podman to map a range of 5000 UIDs inside the container, starting with UID 100000 outside the container (so the range is 100000-104999) to a range starting at UID 0 inside the container (so the range is 0-4999). Inside the container, if my process is running as UID 1, it is 100001 on the host + +Since the real UID=0 is not mapped into the container, any file owned by root will be treated as owned by nobody. Even if the process inside the container has **CAP_DAC_OVERRIDE** , it can't override this protection. **DAC_OVERRIDE** enables root processes to read/write any file on the system, even if the process was not owned by root or world readable or writable. + +User namespace capabilities are not the same as capabilities on the host. They are namespaced capabilities. This means my container root has capabilities only within the container—really only across the range of UIDs that were mapped into the user namespace. If a container process escaped the container, it wouldn't have any capabilities over UIDs not mapped into the user namespace, including UID=0. Even if the processes could somehow enter another container, they would not have those capabilities if the container uses a different range of UIDs. + +Note that SELinux and other technologies also limit what would happen if a container process broke out of the container. + +### Using `podman top` to show user namespaces + +We have added features to **podman top** to allow you to examine the usernames of processes running inside a container and identify their real UIDs on the host. + +Let's start by running a sleep container using our UID mapping. + +``` +$ sudo podman run --uidmap 0:100000:5000 -d fedora sleep 1000 +``` + +Now run **podman top** : + +``` +$ sudo podman top --latest user huser +USER   HUSER +root   100000 + +$ ps -ef | grep sleep +100000   21821 21809  0 08:04 ?         00:00:00 /usr/bin/coreutils --coreutils-prog-shebang=sleep /usr/bin/sleep 1000 +``` + +Notice **podman top** reports that the user process is running as root inside the container but as UID 100000 on the host (HUSER). Also the **ps** command confirms that the sleep process is running as UID 100000. + +Now let's run a second container, but this time we will choose a separate UID map starting at 200000. + +``` +$ sudo podman run --uidmap 0:200000:5000 -d fedora sleep 1000 +$ sudo podman top --latest user huser +USER   HUSER +root   200000 + +$ ps -ef | grep sleep +100000   21821 21809  0 08:04 ?         00:00:00 /usr/bin/coreutils --coreutils-prog-shebang=sleep /usr/bin/sleep 1000 +200000   23644 23632  1 08:08 ?         00:00:00 /usr/bin/coreutils --coreutils-prog-shebang=sleep /usr/bin/sleep 1000 +``` + +Notice that **podman top** reports the second container is running as root inside the container but as UID=200000 on the host. + +Also look at the **ps** command—it shows both sleep processes running: one as 100000 and the other as 200000. + +This means running the containers inside separate user namespaces gives you traditional UID separation between processes, which has been the standard security tool of Linux/Unix from the beginning. + +### Problems with user namespaces + +For several years, I've advocated user namespace as the security tool everyone wants but hardly anyone has used. The reason is there hasn't been any filesystem support or a shifting file system. + +In containers, you want to share the **base** image between lots of containers. The examples above use the Fedora base image in each example. Most of the files in the Fedora image are owned by real UID=0. If I run a container on this image with the user namespace 0:100000:5000, by default it sees all of these files as owned by nobody, so we need to shift all of these UIDs to match the user namespace. For years, I've wanted a mount option to tell the kernel to remap these file UIDs to match the user namespace. Upstream kernel storage developers continue to investigate and make progress on this feature, but it is a difficult problem. + + +Podman can use different user namespaces on the same image because of automatic [chowning][6] built into [containers/storage][7] by a team led by Nalin Dahyabhai. Podman uses containers/storage, and the first time Podman uses a container image in a new user namespace, container/storage "chowns" (i.e., changes ownership for) all files in the image to the UIDs mapped in the user namespace and creates a new image. Think of this as the **fedora:0:100000:5000** image. + +When Podman runs another container on the image with the same UID mappings, it uses the "pre-chowned" image. When I run the second container on 0:200000:5000, containers/storage creates a second image, let's call it **fedora:0:200000:5000**. + +Note if you are doing a **podman build** or **podman commit** and push the newly created image to a container registry, Podman will use container/storage to reverse the shift and push the image with all files chowned back to real UID=0. + +This can cause a real slowdown in creating containers in new UID mappings since the **chown** can be slow depending on the number of files in the image. Also, on a normal [OverlayFS][8], every file in the image gets copied up. The normal Fedora image can take up to 30 seconds to finish the chown and start the container. + +Luckily, the Red Hat kernel storage team, primarily Vivek Goyal and Miklos Szeredi, added a new feature to OverlayFS in kernel 4.19. The feature is called **metadata only copy-up**. If you mount an overlay filesystem with **metacopy=on** as a mount option, it will not copy up the contents of the lower layers when you change file attributes; the kernel creates new inodes that include the attributes with references pointing at the lower-level data. It will still copy up the contents if the content changes. This functionality is available in the Red Hat Enterprise Linux 8 Beta, if you want to try it out. + +This means container chowning can happen in a couple of seconds, and you won't double the storage space for each container. + +This makes running containers with tools like Podman in separate user namespaces viable, greatly increasing the security of the system. + +### Going forward + +I want to add a new flag, like **\--userns=auto** , to Podman that will tell it to automatically pick a unique user namespace for each container you run. This is similar to the way SELinux works with separate multi-category security (MCS) labels. If you set the environment variable **PODMAN_USERNS=auto** , you won't even need to set the flag. + +Podman is finally allowing users to run containers in separate user namespaces. Tools like [Buildah][9] and [CRI-O][10] will also be able to take advantage of user namespaces. For CRI-O, however, Kubernetes needs to understand which user namespace will run the container engine, and the upstream is working on that. + +In my next article, I will explain how to run Podman as non-root in a user namespace. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/podman-and-user-namespaces + +作者：[Daniel J Walsh][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/rhatdan +[b]: https://github.com/lujun9972 +[1]: https://podman.io/ +[2]: https://github.com/containers/libpod +[3]: https://opensource.com/article/18/10/podman-more-secure-way-run-containers +[4]: http://man7.org/linux/man-pages/man7/user_namespaces.7.html +[5]: https://chmodcommand.com/chmod-660/ +[6]: https://en.wikipedia.org/wiki/Chown +[7]: https://github.com/containers/storage +[8]: https://en.wikipedia.org/wiki/OverlayFS +[9]: https://buildah.io/ +[10]: http://cri-o.io/ diff --git a/sources/tech/20181213 What is PPA- Everything You Need to Know About PPA in Linux.md b/sources/tech/20181213 What is PPA- Everything You Need to Know About PPA in Linux.md new file mode 100644 index 0000000000..d0132aebf8 --- /dev/null +++ b/sources/tech/20181213 What is PPA- Everything You Need to Know About PPA in Linux.md @@ -0,0 +1,315 @@ +[#]: collector: (lujun9972) +[#]: translator: (jlztan) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (What is PPA? Everything You Need to Know About PPA in Linux) +[#]: via: (https://itsfoss.com/ppa-guide/) +[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/) + +What is PPA? Everything You Need to Know About PPA in Linux +====== + +**Brief: An in-depth article that covers almost all the questions around using PPA in Ubuntu and other Linux distributions.** + +If you have been using Ubuntu or some other Linux distribution based on Ubuntu such as Linux Mint, Linux Lite, Zorin OS etc, you may have come across three magical lines of this sort: + +``` +sudo add-apt-repository ppa:dr-akulavich/lighttable +sudo apt-get update +sudo apt-get install lighttable-installer +``` + +A number of websites suggest these kind of lines to [install applications in Ubuntu][1]. This is what is called installing an application using PPA. + +But what is PPA? Why is it used? Is it safe to use PPA? How to properly use PPA? How to delete a PPA? + +I’ll answer all of the above questions in this detailed guide. Even if you already know a few things about PPAs, I am sure this article will still add to your knowledge. + +Do note that I am writing this article using Ubuntu. Therefore I’ll use the term Ubuntu almost everywhere but the explanations and steps are also applicable to other Debian/Ubuntu based distributions. + +### What is PPA? Why is it used? + +![Everything you need to know about PPA in Ubuntu Linux][2] + +PPA stands for Personal Package Archive. + +Does that make sense? Probably not. + +Before you understand PPA, you should know the concept of repositories in Linux. I won’t go into details here though. + +#### Concept of repositories and package management + +A repository is a collection of files that has information about various software, their versions and some other details like the checksum. Each Ubuntu version has its own official set of four repositories: + + * **Main** – Canonical-supported free and open-source software. + + * **Universe** – Community-maintained free and open-source software. + + * **Restricted** – Proprietary drivers for devices. + + * **Multiverse** – Software restricted by copyright or legal issues. + + + + +You can see such repositories for all Ubuntu versions [here][3]. You can browse through them and also go to the individual repositories. For example, Ubuntu 16.04 main repository can be found [here][4]. + +So basically it’s a web URL that has information about the software. How does your system know where are these repositories? + +This information is stored in the sources.list file in the directory /etc/apt. If you look at its content, you’ll see that it has the URL of the repositories. The lines with # at the beginning are ignored. + +Now when you run the command sudo apt update, your system uses [APT tool][5] to check against the repo and stores the information about the software and their version in a cache. When you use the command sudo apt install package_name, it uses the information to get that package from the URL where the actual software is stored. + +If the repository doesn’t have the information about a certain package, you’ll see an error like: + +``` +E: Unable to locate package +``` + +At this point, I recommend reading my [guide to using apt commands][6]. This will give you a much better understanding of apt commands, update etc. + +So this was about repositories. But what is PPA? How does it enter into the picture? + +#### Why is PPA used? + +As you can see, Ubuntu controls what software and more importantly which version of a software you get on your system. But imagine if a software developer releases a new version of the software. + +Ubuntu won’t make it available immediately. There is a procedure to check if the new version of the software is compatible with the system or not. This ensures the stability of the system. + +But this also means that it will be some weeks or in some cases, some months before it is made available by Ubuntu. Not everyone would want to wait that long to get their hands on the new version of their favorite software. + +Similarly, suppose someone develops a software and wants Ubuntu to include that software in the official repositories. It again will take months before Ubuntu makes a decision and includes it in the official repositories. + +Another case would be during beta testing. Even if a stable version of the software is available in the official repositories, a software developer may want some end users to test their upcoming release. How do they enable the end user to beta test the upcoming release? + +Enter PPA! + +### How to use PPA? How does PPA work? + +[PPA][7], as I already told you, means Personal Package Archive. Mind the word ‘Personal’ here. That gives the hint that this is something exclusive to a developer and is not officially endorsed by the distribution. + +Ubuntu provides a platform called Launchpad that enables software developers to create their own repositories. An end user i.e. you can add the PPA repository to your sources.list and when you update your system, your system would know about the availability of this new software and you can install it using the standard sudo apt install command like this. + +`sudo add-apt-repository ppa:dr-akulavich/lighttable` +`sudo apt-get update` +`sudo apt-get install lighttable-installer` + +To summarize: + + * sudo add-apt-repository <– This command adds the PPA repository to the list. + * sudo apt-get update <– This command updates the list of the packages that can be installed on the system. + * sudo apt-get install <– This command installs the package. + + + +You see that it is important to use the command sudo apt update or else your system will not know when a new package is available. + +Now let’s take a look at the first command in a bit more detail. + +``` +sudo add-apt-repository ppa:dr-akulavich/lighttable +``` + +You would notice that this command doesn’t have a URL to the repository. This is because the tool has been designed to abstract the information about URL from you. + +Just a small note. If you add ppa:dr-akulavich/lighttable, you get Light Table. But if you add ppa:dr-akulavich, you’ll get all the repository or packages mentioned in the ‘upper repository’. It’s hierarchical. + +Basically, when you add a PPA using add-apt-repository, it will do the same action as if you manually run these commands: + +``` +deb http://ppa.launchpad.net/dr-akulavich/lighttable/ubuntu YOUR_UBUNTU_VERSION_HERE main +deb-src http://ppa.launchpad.net/dr-akulavich/lighttable/ubuntu YOUR_UBUNTU_VERSION_HERE main +``` + +The above two lines are the traditional way to add any repositories to your sources.list. But PPA does it automatically for you, without wondering about the exact repository URL and operating system version. + +One important thing to not here is that when you use PPA, it doesn’t change your original sources.list. Instead, it creates two files in /etc/apt/sources.d directory, a list and a back up file with suffix ‘save’. + +![Using a PPA in Ubuntu][8]PPA create separate sources.list + +The files with suffix ‘list’ has the command that adds the information about the repository. + +![PPA add repository information][9]Content of source.list of a PPA + +This is a safety measure to ensure that adding PPAs don’t mess with the original sources.list. It also helps in removing the PPA. + +#### Why PPA? Why not DEB packages? + +You may ask why should you use PPA when it involves using command line which might not be preferred by everyone. Why not just distribute a DEB package that can be installed graphically? + +The answer lies in the update procedure. If you install a software using a DEB package, there is no guarantee that the installed software will be updated to a newer version when you run sudo apt update && sudo apt upgrade. + +It’s because the apt upgrade procedure relies on the sources.list. If there is no entry for a software, it doesn’t get the update via the standard software updater. + +So does it mean software installed using DEB never gets an update? No, not really. It depends on how the package was created. + +Some developers automatically add an entry to the sources.list and then it is updated like a regular software. Google Chrome is one such example. + +Some software would notify you of availability of a new version when you try to run it. You’ll have to download the new DEB package and run it again to update the current software to a newer version. Oracle Virtual Box is an example in this case. + +For the rest of the DEB packages, you’ll have to manually look for an update and this is not convenient, especially if your software is meant for beta testers. You need to add more updates frequently. This is where PPA come to the rescue. + +#### Offical PPA vs unofficial PPA + +You may also hear the term official PPA or unofficial PPA. What’s the difference? + +When developers create PPA for their software, it is called the official PPA. Quite obviously because it is coming from none other than the project developers. + +But at times, individuals create PPA of projects that were created by other developers. + +Why would someone do that? Because many developers just provide the source code of the software and you know that [installing software from source code in Linux][10] is a pain and not everyone could or would do that. + +This is why volunteers take it upon themselves to create a PPA from those source code so that other users can install the software easily. After all, using those 3 lines is a lot easier than battling the source code installation. + +#### Make sure that a PPA is available for your distribution version + +When it comes to using PPA in Ubuntu or any other Debian based distribution, there are a few things you should keep in mind. + +Not every PPA is available for your particular version. You should know [which Ubuntu version][11] you are using. The codename of the release is important because when you go to the webpage of a certain PPA, you can see which Ubuntu versions are supported by the PPA. + +For other Ubuntu-based distributions, you can check the content of /etc/os-release to [find out the Ubuntu version][11] information. + +![Verify PPA availability for Ubuntu version][12]Check if PPA is available for your Ubuntu version + +How to know the PPA url? Simply search on the internet with the PPA name like ppa:dr-akulavich/lighttable and you’ll get the first result from [Launchpad][13], the official platform for hosting PPA. You can also go to Launchpad and search for the required PPA directly there. + +If you don’t verify and add the PPA, you may see an error like this when you try to install a software not available for your version. + +``` +E: Unable to locate package +``` + +What’s worse is that since it has been added to your source.list, each time you run software updater, you’ll see an error “[Failed to download repository information][14]“. + +![Failed to download repository information Ubuntu 13.04][15] + +If you run sudo apt update in the terminal, the error will have more details about which repository is causing the trouble. You can see something like this in the end of the output of sudo apt update: + +``` +W: Failed to fetch http://ppa.launchpad.net/venerix/pkg/ubuntu/dists/raring/main/binary-i386/Packages  404  Not Found +E: Some index files failed to download. They have been ignored, or old ones used instead. +``` + +Which is self-explanatory because the system cannot find the repository for your version. Remember what we saw earlier about repository structure? APT will try to look for software information in the place /ubuntu/dists/Ubuntu_Version + +And if the PPA for the specific version is not available, it will never be able to open the URL and you get the famous 404 error. + +#### Why are PPAs not available for all the Ubuntu release versions? + +It is because someone has to compile the software and create a PPA out of it on the specific versions. Considering that a new Ubuntu version is released every six months, it’s a tiresome task to update the PPA for every Ubuntu release. Not all developers have time to do that. + +#### How to install the application if PPA is not available for your version? + +It is possible that though the PPA is not available for your Ubuntu version, you could still download the DEB file and install the application + +Let’s say that you go to the Light Table PPA. Using the knowledge about PPA you just learned, you realize that the PPA is not available for your specific Ubuntu release. + +What you can do is to click on the ‘View package details’. + +![Get DEB file from PPA][16] + +And in here, you can click on a package to reveal more details. You’ll also find the source code and the DEB file of the package here. + +![Download DEB file from PPA][17] + +I advise [using Gdebi to install these DEB files][18] instead of the Software Center because Gdebi is a lot better at handling dependencies. + +Do note that the package installed this way might not get any future updates. + +I think you have read enough about adding PPAs. How about removing a PPA and the software installed by it? + +### How to delete PPA? + +I have written about [deleting PPA][19] in the past. I am going to describe the same methods here as well. + +I advise deleting the software that you installed from a PPA before removing the PPA. If you just remove the PPA, the installed software remains in the system but it won’t get any updates. You wouldn’t want that, would you? + +So, the question comes, how to know which application was installed by which PPA? + +#### Find packages installed by a PPA and remove them + +Ubuntu Software Center doesn’t help here. You’ll have to use Synaptic package manager here which has more advanced features. + +You can install Synaptic from Software Center or use the command below: + +``` +sudo apt install synaptic +``` + +Once installed, start Synaptic package manager and select Origin. You’ll see various repositories added to the system. PPA entries will be labeled with prefix PPA. Click on them to see the packages that are available by the PPA. Installed software will have appropriate symbol before it. + +![Managing PPA with Synaptic package manager][20]Find packages installed via a PPA + +Once you have found the packages, you can delete them from Synaptic itself. Otherwise, you always have the option to use the command line: + +``` +sudo apt remove package_name +``` + +Once you have removed the packages installed by a PPA, you can continue to remove the PPA from your sources.list. + +#### Remove a PPA graphically + +Go to Software & Updates and then go to tab Other Software. Look for the PPA that you want to remove: + +![Delete a PPA from Software Source][21] + +You have two options here. Either you deselect the PPA or you choose the Remove option. + +The difference is that when you deselect a PPA entry, your system will comment out the repository entry in its ppa_name.list file in /etc/apt/sources.list.d but if you choose the Remove option, it will delete the repository entry from its ppa_name.list file in /etc/apt/sources.list.d directory. + +In both the cases, the files ppa_name.list remains in the said directory, even if it is empty. + +### Is it safe to use PPA? + +It is a subjective question. Purists abhor PPA because most of the time PPAs are from third-party developers. But at the same time, PPAs are popular in the Debian/Ubuntu world as they provide an easier installation option. + +As far as the security is concerned, it’s less likely that you use a PPA and your Linux system is hacked or injected with malware. I don’t recall such an incident ever happened so far. + +Official PPAs can be used without thinking twice. Using unofficial PPA is entirely your decision. + +As a rule of thumb, you should avoid installing a program via a third party PPA if it the program requires sudo access to run. + +### What do you think about using PPA? + +I know it’s a long read but I wanted to give you a better understanding of PPA. I hope this detailed guide answered most of your questions about using PPA. + +If you have more questions about PPA, please feel free to ask in the comment section. + +If you notice any technical or grammatical error or if you have suggestions for improving this article, please let me know. + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/ppa-guide/ + +作者：[Abhishek Prakash][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/abhishek/ +[b]: https://github.com/lujun9972 +[1]: https://itsfoss.com/remove-install-software-ubuntu/ +[2]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/what-is-ppa.png?resize=800%2C450&ssl=1 +[3]: http://archive.ubuntu.com/ubuntu/dists/ +[4]: http://archive.ubuntu.com/ubuntu/dists/xenial/main/ +[5]: https://wiki.debian.org/Apt +[6]: https://itsfoss.com/apt-command-guide/ +[7]: https://launchpad.net/ubuntu/+ppas +[8]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/01/ppa-sources-list-files.png?resize=800%2C259&ssl=1 +[9]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/01/content-of-ppa-list.png?ssl=1 +[10]: https://itsfoss.com/install-software-from-source-code/ +[11]: https://itsfoss.com/how-to-know-ubuntu-unity-version/ +[12]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2017/12/verify-ppa-availibility-version.jpg?resize=800%2C481&ssl=1 +[13]: https://launchpad.net/ +[14]: https://itsfoss.com/failed-to-download-repository-information-ubuntu-13-04/ +[15]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2013/04/Failed-to-download-repository-information-Ubuntu-13.04.png?ssl=1 +[16]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/12/deb-from-ppa.jpg?resize=800%2C483&ssl=1 +[17]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/12/deb-from-ppa-2.jpg?resize=800%2C477&ssl=1 +[18]: https://itsfoss.com/gdebi-default-ubuntu-software-center/ +[19]: https://itsfoss.com/how-to-remove-or-delete-ppas-quick-tip/ +[20]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/01/ppa-synaptic-manager.jpeg?resize=800%2C394&ssl=1 +[21]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2012/08/Delete-a-PPA.jpeg?ssl=1 diff --git a/sources/tech/20181214 The Linux terminal is no one-trick pony.md b/sources/tech/20181214 The Linux terminal is no one-trick pony.md new file mode 100644 index 0000000000..28964b249c --- /dev/null +++ b/sources/tech/20181214 The Linux terminal is no one-trick pony.md @@ -0,0 +1,66 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (The Linux terminal is no one-trick pony) +[#]: via: (https://opensource.com/article/18/12/linux-toy-ponysay) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +The Linux terminal is no one-trick pony +====== +Bring the magic of My Little Pony to your Linux command line. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-ponysay.png?itok=ehl6pTr_) + +Welcome to another day of the Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is. We’re figuring that out as we go, but generally, it could be a game, or any simple diversion that helps you have fun at the terminal. + +Some of you will have seen various selections from our calendar before, but we hope there’s at least one new thing for everyone. + +Reader [Lori][1] made the suggestion of today's toy in a comment on my previous article on [cowsay][2]: + +"Hmmm, I've been playing with something called ponysay which seems to be a full-color variant on your cowsay." + +Intrigued, I had to check it out, and I was not disappointed with what I found. + +In a nutshell, **[ponysay][3]** is exactly that: a rewrite of **cowsay** that includes many full-color characters from [My Little Pony][4], that you can use to output phrases at the Linux command line. It's actually a really well-done project, that features over 400 characters and character combinations, and is incredibly well documented in a [78-page PDF][5] covering full usage. + +To install **ponysay** , you'll want to check out the project [README][6] to select the installation method that works best for your distribution and situation. Since ponysay didn't appear to be packaged for my distribution, Fedora, I opted to try out the Docker container image, but do what works best for you; installation from source may also work for you. + +I was curious to try out [**podman**][7] as a drop-in replacement for **docker** for a casual container users, and for me at least, it just worked! + +``` +$ podman run -ti --rm mpepping/ponysay 'Ponytastic' +``` + +The outputs are amazing, and I challenge you to try it out and let me know your favorite. Here was one of mine: + +![](https://opensource.com/sites/default/files/uploads/linux-toy-ponysay-output.png) + +It's developers chose to write the code in [Pony][8]! (Update: Sadly, I was wrong about this. It's written in Python, though GitHub believes it to be Pony because of the file extensions.) Ponysay is licensed under the GPL version 3, and you can pick up its source code [on GitHub][3]. + +Do you have a favorite command-line toy that you think I ought to profile? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [Relax by the fire at your Linux terminal][9], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-ponysay + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/users/n8chz +[2]: https://opensource.com/article/18/12/linux-toy-cowsay +[3]: https://github.com/erkin/ponysay +[4]: https://en.wikipedia.org/wiki/My_Little_Pony +[5]: https://github.com/erkin/ponysay/blob/master/ponysay.pdf?raw=true +[6]: https://github.com/erkin/ponysay/blob/master/README.md +[7]: https://opensource.com/article/18/10/podman-more-secure-way-run-containers +[8]: https://opensource.com/article/18/5/pony +[9]: https://opensource.com/article/18/12/linux-toy-aafire diff --git a/sources/tech/20181214 Tips for using Flood Element for performance testing.md b/sources/tech/20181214 Tips for using Flood Element for performance testing.md new file mode 100644 index 0000000000..90994b0724 --- /dev/null +++ b/sources/tech/20181214 Tips for using Flood Element for performance testing.md @@ -0,0 +1,180 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Tips for using Flood Element for performance testing) +[#]: via: (https://opensource.com/article/18/12/tips-flood-element-testing) +[#]: author: (Nicole van der Hoeven https://opensource.com/users/nicolevanderhoeven) + +Tips for using Flood Element for performance testing +====== +Get started with this powerful, intuitive load testing tool. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/tools_sysadmin_cloud.png?itok=sUciG0Cn) + +In case you missed it, there’s a new performance test tool on the block: [Flood Element][1]. It’s a scalable, browser-based tool that allows you to write scripts in JavaScript that interact with web pages like a real user would. + +Browser Level Users is a [newer approach to load testing][2] that overcomes many of the common challenges we hear about traditional methods of testing. It offers: + + * Scripting that is akin to common functional tools like Selenium and easier to learn + * More realistic results that are based on true browser performance rather than API response + * The ability to test against all components of your web app, including things like JavaScript that are rendered via the browser + + + +Given the above benefits, it’s a no-brainer to check out Flood Element for your web load testing, especially if you have struggled with existing tools like JMeter or HP LoadRunner. + +Pairing Element with [Flood][3] turns it into a pretty powerful load test tool. We have a [great guide here][4] that you can follow if you’d like to get started. I’ve been using and testing Element for several months now, and I’d like to share some tips I’ve learned along the way. + +### Initializing your script + +You can always start from scratch, but the quickest way to get started is to type `element init myfirstelementtest` from your terminal, filling in your preferred project name. + +You’ll then be asked to type the title of your test as well as the URL you’d like to script against. After a minute, you’ll see that a new directory has been created: + +![](https://opensource.com/sites/default/files/uploads/image_1_-_new_directory.png) + +Element will automatically create a file called **test.ts**. This file contains the skeleton of a script, along with some sample code to help you find a button and then click on it. But before you open it, let’s move on to… + +### Choosing the right text editor + +Scripting in Element is already pretty simple, but two things that help are syntax highlighting and code completion. Syntax highlighting will greatly improve the experience of learning a new test tool like Element, and code completion will make your scripting lightning-fast as you become more experienced. My text editor of choice is [Visual Studio Code][5], which has both of those features. It’s slick and clean, and it does the job. + +Syntax highlighting is when the text editor intelligently changes the font color of your code according to its role in the programming language you’re using. Here’s a screenshot of the **test.ts** file we generated earlier in VS Code to show you what I mean: + +![](https://opensource.com/sites/default/files/uploads/image_2_test.ts_.png) + +This makes it easier to make sense of the code at a glance: Comments are in green, values and labels are in orange, etc. + +Code completion is when you start to type something, and VS Code helpfully opens a context menu with suggestions for methods you can use. + +![][6] + +I love this because it means I don’t need to remember the exact name of the method. It also suggests names of variables you’ve already defined and highlights code that doesn’t make sense. This will help to make your tests more maintainable and readable for others, which is a great benefit as you look to scale your testing out in the future. + +![](https://opensource.com/sites/default/files/image-4-element-visible-copy.gif) + +### Taking screenshots + +One of the most powerful features of Element is its ability to take screenshots. I find it immensely useful when debugging because sometimes it’s just easier to see what’s going on visually. With protocol-based tools, debugging can be a much more involved and technical process. + +There are two ways to take screenshots in Element: + + 1. Add a setting to automatically take a screenshot when an error is encountered. You can do this by setting `screenshotOnFailure` to "true" in `TestSettings`: + + + +``` +export const settings: TestSettings = { +        device: Device.iPadLandscape, +        userAgent: 'flood-chrome-test', +        clearCache: true, +        disableCache: true, +        screenshotOnFailure: true, +} +``` + + 2. Explicitly take a screenshot at a particular point in the script. You can do this by adding + + + +``` +await browser.takeScreenshot() +``` + +to your code. + +### Viewing screenshots + +Once you’ve taken screenshots within your tests, you will probably want to view them and know that they will be stored for future safekeeping. Whether you are running your test locally on have uploaded it to Flood to run with increased concurrency, Flood Element has you covered. + +**Locally run tests** + +Screenshots will be saved as .jpg files in a timestamped folder corresponding to your run. It should look something like this: **…myfirstelementtest/tmp/element-results/test/2018-11-20T135700.595Z/flood/screenshots/**. The screenshots will be uniquely named so that new screenshots, even for the same step, don’t overwrite older ones. + +However, I rarely need to look up the screenshots in that folder because I prefer to see them in iTerm2 for MacOS. iTerm is an alternative to the terminal that works particularly well with Element. When you take a screenshot, iTerm actually shows it in-line: + +![](https://opensource.com/sites/default/files/uploads/image_5_iterm_inline.png) + +**Tests run in Flood** + +Running an Element script on Flood is ideal when you need larger concurrency. Rather than accessing your screenshot locally, Flood will centralize the images into your account, so the images remain even after the cloud load injectors are destroyed. You can get to the screenshot files by downloading Archived Results: + +![](https://opensource.com/sites/default/files/image_6_archived_results.png) + +You can also click on a step on the dashboard to see a filmstrip of your test: + +![](https://opensource.com/sites/default/files/uploads/image_7_filmstrip_view.png) + +### Using logs + +You may need to check out the logs for more technical debugging, especially when the screenshots don’t tell the whole story. Again, whether you are running your test locally or have uploaded it to Flood to run with increased concurrency, Flood Element has you covered. + +**Locally run tests** + +You can print to the console by typing, for example: `console.log('orderValues = ’ + orderValues)` + +This will print the value of the variable `orderValues` at that point in the script. You would see this in your terminal if you’re running Element locally. + +**Tests run in Flood** + +If you’re running the script on Flood, you can either download the log (in the same Archived Results zipped file mentioned earlier) or click on the Logs tab: + +![](https://opensource.com/sites/default/files/uploads/image_8_logs_tab.png) + +### Fun with flags + +Element comes with a few flags that give you more control over how the script is run locally. Here are a few of my favorites: + +**Headless flag** + +When in doubt, run Element in non-headless mode to see the script actually opening the web app on Chrome and interacting with the page. This is only possible locally, but there’s nothing like actually seeing for yourself what’s happening in real time instead of relying on screenshots and logs after the fact. To enable this mode, add the flag when running your test: + +``` +element run myfirstelementtest.ts --no-headless +``` + +**Watch flag** + +Element will automatically close the browser window when it encounters an error or finishes the iteration. Adding `--watch` will leave the browser window open and then monitor the script. As soon as the script is saved, it will automatically run it in the same window from the beginning. Simply add this flag like the above example: + +``` +--watch +``` + +**Dev tools flag** + +This opens a browser instance and runs the script with the Chrome Dev Tools open, allowing you to find locators for the next action you want to script. Simply add this flag as in the first example: + +``` +--dev-tools +``` + +For more flags, use `element run --help`. + +### Try Element + +You’ve just gotten a crash course on Flood Element and are ready to get started. [Download Element][1] to start writing functional test scripts and reusing them as load test scripts on Flood. If you don’t have a Flood account, you can easily sign up for a free trial [on the Flood website][7]. + +We’re proud to contribute to the open source community and can’t wait to have you try this new addition to the Flood line. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/tips-flood-element-testing + +作者：[Nicole van der Hoeven][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/nicolevanderhoeven +[b]: https://github.com/lujun9972 +[1]: https://element.flood.io/ +[2]: https://flood.io/blog/why-you-should-load-test-with-browsers/ +[3]: https://flood.io/ +[4]: https://help.flood.io/getting-started-with-load-testing/step-by-step-guide-flood-element +[5]: https://code.visualstudio.com/ +[6]: https://flood.io/wp-content/uploads/2018/11/vscode-codecompletion2.gif +[7]: https://flood.io/load-performance-testing-tool/free-load-testing-trial/ diff --git a/sources/tech/20181215 Head to the arcade in your Linux terminal with this Pac-man clone.md b/sources/tech/20181215 Head to the arcade in your Linux terminal with this Pac-man clone.md new file mode 100644 index 0000000000..3bd36352a4 --- /dev/null +++ b/sources/tech/20181215 Head to the arcade in your Linux terminal with this Pac-man clone.md @@ -0,0 +1,52 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Head to the arcade in your Linux terminal with this Pac-man clone) +[#]: via: (https://opensource.com/article/18/12/linux-toy-myman) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Head to the arcade in your Linux terminal with this Pac-man clone +====== +Want to recreate the magic of your favorite arcade game? Today's command-line toy will transport you back in time. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-myman.png?itok=9j1DFgH0) + +Welcome back to another day of the Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what command-line toys are all about. Basically, they're games and simple diversions that help you have fun at the terminal. + +Some are new, and some are old classics. We hope you enjoy. + +Today's toy, MyMan, is a fun clone of the classic arcade game [Pac-Man][1]. (You didn't think this was going to be about the [similarly-named][2] Linux package manager, did you?) If you're anything like me, you spent more than your fair share of quarters trying to hit a high score Pac-Man back in the day, and still give it a go whenever you get a chance. + +MyMan isn't the only Pac-Man clone for the Linux terminal, but it's the one I chose to include because 1) I like its visual style, which rings true to the original and 2) it's conveniently packaged for my Linux distribution so it was an easy install. But you should check out your other options as well. Here's [another one][3] that looks like it may be promising, but I haven't tried it. + +Since MyMan was packaged for Fedora, installation was as simple as: + +``` +$ dnf install myman +``` + +MyMan is made available under an MIT license and you can check out the source code on [SourceForge][4]. +![](https://opensource.com/sites/default/files/uploads/linux-toy-myman-animated.gif) +Do you have a favorite command-line toy that you think I ought to profile? The calendar for this series is mostly filled out but I've got a few spots left. Let me know in the comments below, and I'll check it out. If there's space, I'll try to include it. If not, but I get some good submissions, I'll do a round-up of honorable mentions at the end. + +Check out yesterday's toy, [The Linux terminal is no one-trick pony][5], and check back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-myman + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://en.wikipedia.org/wiki/Pac-Man +[2]: https://wiki.archlinux.org/index.php/pacman +[3]: https://github.com/YoctoForBeaglebone/pacman4console +[4]: https://myman.sourceforge.io/ +[5]: https://opensource.com/article/18/12/linux-toy-ponysay diff --git a/sources/tech/20181216 Schedule a visit with the Emacs psychiatrist.md b/sources/tech/20181216 Schedule a visit with the Emacs psychiatrist.md new file mode 100644 index 0000000000..6d72cda348 --- /dev/null +++ b/sources/tech/20181216 Schedule a visit with the Emacs psychiatrist.md @@ -0,0 +1,62 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Schedule a visit with the Emacs psychiatrist) +[#]: via: (https://opensource.com/article/18/12/linux-toy-eliza) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Schedule a visit with the Emacs psychiatrist +====== +Eliza is a natural language processing chatbot hidden inside of one of Linux's most popular text editors. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-eliza.png?itok=3ioiBik_) + +Welcome to another day of the 24-day-long Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is. We’re figuring that out as we go, but generally, it could be a game, or any simple diversion that helps you have fun at the terminal. + +Some of you will have seen various selections from our calendar before, but we hope there’s at least one new thing for everyone. + +Today's selection is a hidden gem inside of Emacs: Eliza, the Rogerian psychotherapist, a terminal toy ready to listen to everything you have to say. + +A brief aside: While this toy is amusing, your health is no laughing matter. Please take care of yourself this holiday season, physically and mentally, and if stress and anxiety from the holidays are having a negative impact on your wellbeing, please consider seeing a professional for guidance. It really can help. + +To launch [Eliza][1], first, you'll need to launch Emacs. There's a good chance Emacs is already installed on your system, but if it's not, it's almost certainly in your default repositories. + +Since I've been pretty fastidious about keeping this series in the terminal, launch Emacs with the **-nw** flag to keep in within your terminal emulator. + +``` +$ emacs -nw +``` + +Inside of Emacs, type M-x doctor to launch Eliza. For those of you like me from a Vim background who have no idea what this means, just hit escape, type x and then type doctor. Then, share all of your holiday frustrations. + +Eliza goes way back, all the way to the mid-1960s a the MIT Artificial Intelligence Lab. [Wikipedia][2] has a rather fascinating look at her history. + +Eliza isn't the only amusement inside of Emacs. Check out the [manual][3] for a whole list of fun toys. + + +![Linux toy: eliza animated][5] + +Do you have a favorite command-line toy that you think I ought to profile? We're running out of time, but I'd still love to hear your suggestions. Let me know in the comments below, and I'll check it out. And let me know what you thought of today's amusement. + +Be sure to check out yesterday's toy, [Head to the arcade in your Linux terminal with this Pac-man clone][6], and come back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-eliza + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://www.emacswiki.org/emacs/EmacsDoctor +[2]: https://en.wikipedia.org/wiki/ELIZA +[3]: https://www.gnu.org/software/emacs/manual/html_node/emacs/Amusements.html +[4]: /file/417326 +[5]: https://opensource.com/sites/default/files/uploads/linux-toy-eliza-animated.gif (Linux toy: eliza animated) +[6]: https://opensource.com/article/18/12/linux-toy-myman diff --git a/sources/tech/20181217 4 cool new projects to try in COPR for December 2018.md b/sources/tech/20181217 4 cool new projects to try in COPR for December 2018.md new file mode 100644 index 0000000000..0564320363 --- /dev/null +++ b/sources/tech/20181217 4 cool new projects to try in COPR for December 2018.md @@ -0,0 +1,93 @@ +[#]: collector: (lujun9972) +[#]: translator: (geekpi) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (4 cool new projects to try in COPR for December 2018) +[#]: via: (https://fedoramagazine.org/4-try-copr-december-2018/) +[#]: author: (Dominik Turecek https://fedoramagazine.org) + +4 cool new projects to try in COPR for December 2018 +====== +![](https://fedoramagazine.org/wp-content/uploads/2017/08/4-copr-945x400.jpg) + +COPR is a [collection][1] of personal repositories for software that isn’t carried in Fedora. Some software doesn’t conform to standards that allow easy packaging. Or it may not meet other Fedora standards, despite being free and open source. COPR can offer these projects outside the Fedora set of packages. Software in COPR isn’t supported by Fedora infrastructure or signed by the project. However, it can be a neat way to try new or experimental software. + +Here’s a set of new and interesting projects in COPR. + +### MindForger + +[MindForger][2] is a Markdown editor and a notebook. In addition to features you’d expect from a Markdown editor, MindForger lets you split a single file into multiple notes. It’s easy to organize the notes and move them around between files, as well as search through them. I’ve been using MindForger for some time for my study notes, so it’s nice that it’s available through COPR now.![][3] + +#### Installation instructions + +The repo currently provides MindForger for Fedora 29 and Rawhide. To install MindForger, use these commands: + +``` +sudo dnf copr enable deadmozay/mindforger +sudo dnf install mindforger +``` + +### Clingo + +[Clingo][4] is a program for solving logical problems using [answer set programming][5] (ASP) modeling language. With ASP, you can declaratively describe a problem as a logical program that Clingo then solves. As a result, Clingo produces solutions to the problem in the form of logical models, called answer sets. + +#### Installation instructions + +The repo currently provides Clingo for Fedora 28 and 29. To install Clingo, use these commands: + +``` +sudo dnf copr enable timn/clingo +sudo dnf install clingo +``` + +### SGVrecord + +[SGVrecord][6] is a simple tool for recording your screen. It allows you to either capture the whole screen or select just a part of it. Furthermore, it is possible to make the record with or without sound. Sgvrecord produces files in WebM format.![][7] + +#### Installation instructions + +The repo currently provides SGVrecord for Fedora 28, 29, and Rawhide. To install SGVrecord, use these commands: + +``` +sudo dnf copr enable youssefmsourani/sgvrecord +sudo dnf install sgvrecord +``` + +### Watchman + +[Watchman][8] is a service for monitoring and recording when changes are done to files. +You can specify directory trees for Watchman to monitor, as well as define actions +that are triggered when specified files are changed. + +#### Installation instructions + +The repo currently provides Watchman for Fedora 29 and Rawhide. To install Watchman, use these commands: + +``` +sudo dnf copr enable eklitzke/watchman +sudo dnf install watchman +``` + + +-------------------------------------------------------------------------------- + +via: https://fedoramagazine.org/4-try-copr-december-2018/ + +作者：[Dominik Turecek][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://fedoramagazine.org +[b]: https://github.com/lujun9972 +[1]: https://copr.fedorainfracloud.org/ +[2]: https://www.mindforger.com/ +[3]: https://fedoramagazine.org/wp-content/uploads/2018/12/mindforger.png +[4]: https://potassco.org/clingo/ +[5]: https://en.wikipedia.org/wiki/Answer_set_programming +[6]: https://github.com/yucefsourani/sgvrecord +[7]: https://fedoramagazine.org/wp-content/uploads/2018/12/SGVrecord.png +[8]: https://facebook.github.io/watchman/ diff --git a/sources/tech/20181217 6 tips and tricks for using KeePassX to secure your passwords.md b/sources/tech/20181217 6 tips and tricks for using KeePassX to secure your passwords.md new file mode 100644 index 0000000000..ad688a7820 --- /dev/null +++ b/sources/tech/20181217 6 tips and tricks for using KeePassX to secure your passwords.md @@ -0,0 +1,78 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (6 tips and tricks for using KeePassX to secure your passwords) +[#]: via: (https://opensource.com/article/18/12/keepassx-security-best-practices) +[#]: author: (Michael McCune https://opensource.com/users/elmiko) + +6 tips and tricks for using KeePassX to secure your passwords +====== +Get more out of your password manager by following these best practices. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/security-lock-password.jpg?itok=KJMdkKum) + +Our increasingly interconnected digital world makes security an essential and common discussion topic. We hear about [data breaches][1] with alarming regularity and are often on our own to make informed decisions about how to use technology securely. Although security is a deep and nuanced topic, there are some easy daily habits you can keep to reduce your attack surface. + +Securing passwords and account information is something that affects anyone today. Technologies like [OAuth][2] help make our lives simpler by reducing the number of accounts we need to create, but we are still left with a staggering number of places where we need new, unique information to keep our records secure. An easy way to deal with the increased mental load of organizing all this sensitive information is to use a password manager like [KeePassX][3]. + +In this article, I will explain the importance of keeping your password information secure and offer suggestions for getting the most out of KeePassX. For an introduction to KeePassX and its features, I highly recommend Ricardo Frydman's article "[Managing passwords in Linux with KeePassX][4]." + +### Why are unique passwords important? + +Using a different password for each account is the first step in ensuring that your accounts are not vulnerable to shared information leaks. Generating new credentials for every account is time-consuming, and it is extremely common for people to fall into the trap of using the same password on several accounts. The main problem with reusing passwords is that you increase the number of accounts an attacker could access if one of them experiences a credential breach. + +It may seem like a burden to create new credentials for each account, but the few minutes you spend creating and recording this information will pay for itself many times over in the event of a data breach. This is where password management tools like KeePassX are invaluable for providing convenience and reliability in securing your logins. + +### 3 tips for getting the most out of KeePassX + +I have been using KeePassX to manage my password information for many years, and it has become a primary resource in my digital toolbox. Overall, it's fairly simple to use, but there are a few best practices I've learned that I think are worth highlighting. + + 1. Add the direct login URL for each account entry. KeePassX has a very convenient shortcut to open the URL listed with an entry. (It's Control+Shift+U on Linux.) When creating a new account entry for a website, I spend some time to locate the site's direct login URL. Although most websites have a login widget in their navigation toolbars, they also usually have direct pages for login forms. By putting this URL into the URL field on the account entry setup form, I can use the shortcut to directly open the login page in my browser. + +![](https://opensource.com/sites/default/files/uploads/keepassx-tip1.png) + + 2. Use the Notes field to record extra security information. In addition to passwords, most websites will ask several questions to create additional authentication factors for an account. I use the Notes sections in my account entries to record these additional factors. + +![](https://opensource.com/sites/default/files/uploads/keepassx-tip2.png) + + 3. Turn on automatic database locking. In the **Application Settings** under the **Tools** menu, there is an option to lock the database after a period of inactivity. Enabling this option is a good common-sense measure, similar to enabling a password-protected screen lock, that will help ensure your password database is not left open and unprotected if someone else gains access to your computer. + +![](https://opensource.com/sites/default/files/uploads/keepassx_application-settings.png) + +### Food for thought + +Protecting your accounts with better password practices and daily habits is just the beginning. Once you start using a password manager, you need to consider issues like protecting the password database file and ensuring you don't forget or lose the master credentials. + +The cloud-native world of disconnected devices and edge computing makes having a central password store essential. The practices and methodologies you adopt will help minimize your risk while you explore and work in the digital world. + + 1. Be aware of retention policies when storing your database in the cloud. KeePassX's database has an open format used by several tools on multiple platforms. Sooner or later, you will want to transfer your database to another device. As you do this, consider the medium you will use to transfer the file. The best option is to use some sort of direct transfer between devices, but this is not always convenient. Always think about where the database file might be stored as it winds its way through the information superhighway; an email may get cached on a server, an object store may move old files to a trash folder. Learn about these interactions for the platforms you are using before deciding where and how you will share your database file. + + 2. Consider the source of truth for your database while you're making edits. After you share your database file between devices, you might need to create accounts for new services or change information for existing services while using a device. To ensure your information is always correct across all your devices, you need to make sure any edits you make on one device end up in all copies of the database file. There is no easy solution to this problem, but you might think about making all edits from a single device or storing the master copy in a location where all your devices can make edits. + + 3. Do you really need to know your passwords? This is more of a philosophical question that touches on the nature of memorable passwords, convenience, and secrecy. I hardly look at passwords as I create them for new accounts; in most cases, I don't even click the "Show Password" checkbox. There is an idea that you can be more secure by not knowing your passwords, as it would be impossible to compel you to provide them. This may seem like a worrisome idea at first, but consider that you can recover or reset passwords for most accounts through alternate verification methods. When you consider that you might want to change your passwords on a semi-regular basis, it almost makes more sense to treat them as ephemeral information that can be regenerated or replaced. + + + + +Here are a few more ideas to consider as you develop your best practices. + +I hope these tips and tricks have helped expand your knowledge of password management and KeePassX. You can find tools that support the KeePass database format on nearly every platform. If you are not currently using a password manager or have never tried KeePassX, I highly recommend doing so now! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/keepassx-security-best-practices + +作者：[Michael McCune][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/elmiko +[b]: https://github.com/lujun9972 +[1]: https://vigilante.pw/ +[2]: https://en.wikipedia.org/wiki/OAuth +[3]: https://www.keepassx.org/ +[4]: https://opensource.com/business/16/5/keepassx diff --git a/sources/tech/20181217 Working with tarballs on Linux.md b/sources/tech/20181217 Working with tarballs on Linux.md new file mode 100644 index 0000000000..2c95f1038f --- /dev/null +++ b/sources/tech/20181217 Working with tarballs on Linux.md @@ -0,0 +1,100 @@ +[#]: collector: (lujun9972) +[#]: translator: (geekpi) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Working with tarballs on Linux) +[#]: via: (https://www.networkworld.com/article/3328840/linux/working-with-tarballs-on-linux.html) +[#]: author: (Sandra Henry-Stocker https://www.networkworld.com/author/Sandra-Henry_Stocker/) + +Working with tarballs on Linux +====== +![](https://images.idgesg.net/images/article/2018/12/tarball-100783148-large.jpg) + +The word “tarball” is often used to describe the type of file used to back up a select group of files and join them into a single file. The name comes from the **.tar** file extension and the **tar** command that is used to group together the files into a single file that is then sometimes compressed to make it smaller for its move to another system. + +Tarballs are often used to back up personal or system files in place to create an archive, especially prior to making changes that might have to be reversed. Linux sysadmins, for example, will often create a tarball containing a series of configuration files before making changes to an application just in case they have to reverse those changes. Extracting the files from a tarball that’s sitting in place will generally be faster than having to retrieve the files from backups. + +### How to create a tarball on Linux + +You can create a tarball and compress it in a single step if you use a command like this one: + +``` +$ tar -cvzf PDFs.tar.gz *.pdf +``` + +The result in this case is a compressed (gzipped) file that contains all of the PDF files that are in the current directory. The compression is optional, of course. A slightly simpler command would just put all of the PDF files into an uncompressed tarball: + +``` +$ tar -cvf PDFs.tar *.pdf +``` + +Note that it’s the **z** in that list of options that causes the file to be compressed or “zipped”. The **c** specifies that you are creating the file and the **v** (verbose) indicates that you want some feedback while the command is running. Omit the **v** if you don't want to see the files listed. + +Another common naming convention is to give zipped tarballs the extension **.tgz** instead of the double extension **.tar.gz** as shown in this command: + +``` +$ tar cvzf MyPDFs.tgz *.pdf +``` + +### How to extract files from a tarball + +To extract all of the files from a gzipped tarball, you would use a command like this: + +``` +$ tar -xvzf file.tar.gz +``` + +If you use the .tgz naming convention, that command would look like this: + +``` +$ tar -xvzf MyPDFs.tgz +``` + +To extract an individual file from a gzipped tarball, you do almost the same thing but add the file name: + +``` +$ tar -xvzf PDFs.tar.gz ShenTix.pdf +ShenTix.pdf +ls -l ShenTix.pdf +-rw-rw-r-- 1 shs shs 122057 Dec 14 14:43 ShenTix.pdf +``` + +You can even delete files from a tarball if the tarball is not compressed. For example, if we wanted to remove tile file that we extracted above from the PDFs.tar.gz file, we would do it like this: + +``` +$ gunzip PDFs.tar.gz +$ ls -l PDFs.tar +-rw-rw-r-- 1 shs shs 10700800 Dec 15 11:51 PDFs.tar +$ tar -vf PDFs.tar --delete ShenTix.pdf +$ ls -l PDFs.tar +-rw-rw-r-- 1 shs shs 10577920 Dec 15 11:45 PDFs.tar +``` + +Notice that we shaved a little space off the tar file while deleting the ShenTix.pdf file. We can then compress the file again if we want: + +``` +$ gzip -f PDFs.tar +ls -l PDFs.tar.gz +-rw-rw-r-- 1 shs shs 10134499 Dec 15 11:51 PDFs.tar.gzFlickr / James St. John +``` + +The versatility of the command line options makes working with tarballs easy and very convenient. + +Join the Network World communities on [Facebook][1] and [LinkedIn][2] to comment on topics that are top of mind. + +-------------------------------------------------------------------------------- + +via: https://www.networkworld.com/article/3328840/linux/working-with-tarballs-on-linux.html + +作者：[Sandra Henry-Stocker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.networkworld.com/author/Sandra-Henry_Stocker/ +[b]: https://github.com/lujun9972 +[1]: https://www.facebook.com/NetworkWorld/ +[2]: https://www.linkedin.com/company/network-world diff --git a/sources/tech/20181218 Insync- The Hassleless Way of Using Google Drive on Linux.md b/sources/tech/20181218 Insync- The Hassleless Way of Using Google Drive on Linux.md new file mode 100644 index 0000000000..c10e7ae4ed --- /dev/null +++ b/sources/tech/20181218 Insync- The Hassleless Way of Using Google Drive on Linux.md @@ -0,0 +1,137 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Insync: The Hassleless Way of Using Google Drive on Linux) +[#]: via: (https://itsfoss.com/insync-linux-review/) +[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/) + +Insync: The Hassleless Way of Using Google Drive on Linux +====== + +Using Google Drive on Linux is a pain and you probably already know that. There is no official desktop client of Google Drive for Linux. It’s been [more than six years since Google promised Google Drive on Linux][1] but it doesn’t seem to be happening. + +In the absence of the official Google Drive client on Linux, you have no option other than trying the alternatives. I have already discussed a number of [tools that allow you to use Google Drive on Linux][2]. One of those to[ols is][3] Insync, and in my opinion, this is your best bet for a native Google Drive experience on desktop Linux. + +Note that Insync is not an open source software. Heck, it is not even free to use. + +But it has so many features that it becomes an essential tool for those Linux users who rely heavily on Google Drive. + +I briefly discussed Insync in the old article about [Google Drive and Linux][2]. In this article, I’ll discuss Insync features in detail. + +### Insync brings native Google Drive experience to Linux desktop + +![Use insync to access Google Drive in Linux][4] + +The core competency of Insync is syncing your Google Drive, but the app is much more than that. It has features to help you maximize and control your productivity, your Google Drive and your files such as: + + * Cross-platform access (supports Linux, Windows and macOS) + * Easy multiple Google Drive accounts access + * Choose your syncing location. Sync files to your hard drive, external drives and NAS! + * Support for features like file matching, symlink and ignore list + + + +Let me show you some of the main features in action: + +#### Cross-platform in true sense + +Insync claims to run the same app across all operating systems i.e., Linux, Windows, and macOS. That means that you can access the same UI across different OSes, making it easy for you to manage your files across multiple machines. + +![The UI of Insync and the default location of the Insync folder.][5]The UI of Insync and the default location of the Insync folder. + +#### Multiple Google account management + +Insync interface allows you to manage multiple Google Drive accounts seamlessly. You can easily switch between several accounts just by clicking your Google account. + +![Switching between multiple Google accounts in Insync][6]Switching between multiple Google accounts + +#### Custom sync folders + +Customize the way you sync your files and folders. You can easily set your syncing destination anywhere on your machine including external drive and network drives. + +![Customize sync location in Insync][7]Customize sync location + +The selective syncing mode also allows you to easily select a number of files and folders you’d want to sync (or unsync) in your local machine. This includes selectively syncing files within folders. + +![Selective synchronization in Insync][8]Selective synchronization + +It has features like file matching and ‘ignore list’ to help you filter files you don’t want to sync or files that you already have on your machine. + +![File matching feature in Insync][9]Avoids duplication of files + +The ‘ignore list’ allows you to set rules to exclude certain type of files from synchronization. + +![Selective syncing based on rules in Insync][10]Selective syncing based on rules + +If you prefer to work out of the desktop, you have an “Add to Insync” feature that will allow you to add any local file to your Drive. + +![Sync files right from your desktop][11]Sync files right from your desktop + +Insync also supports symlinks for those with workflows that use symbolic links. To learn more about Insync and symlinks, you can refer to [this article.][12] + +#### Exclusive features for Linux + +Insync supports the most commonly used 64-bit Linux distributions like **Ubuntu, Debian and Fedora**. You can check out the full list of distribution support [here][13]. + +Insync also has [headless][14] support for those looking to sync through the command line interface. This is perfect if you use a distro that is not fully supported by the GUI app or if you are working with servers or if you simply prefer the CLI. + +![Insync CLI][15]Command Line Interface + +You can learn more about installing and running Insync headless [here][16]. + +### Insync pricing and special discount + +Insync is a premium tool and it comes with a [price tag][17]. You have 2 licenses to choose from: + + * **Prime** is priced at $29.99 per Google account. You’ll get access to: cross-platform syncing, multiple accounts access and **support**. + * **Teams** is priced at $49.99 per Google account. You’ll be able to access all the Prime features + Team Drives syncing + + + +It’s a one-time fee which means once you buy it, you don’t have to pay it again. In a world where everything is paid monthly, it’s refreshing to pay for software that is still one-time! + +Each Google account has a 15-day free trial that will allow you to test the full suite of features, including [Team Drives][18] syncing. + +If you think it’s a bit expensive for your budget, I have good news for you. As an It’s FOSS reader, you get Insync at 25% discount. + +Just use the code ITSFOSS25 at checkout time and you will get 25% immediate discount on any license. Isn’t it cool? + +If you are not certain yet, you can try Insync free for 15 days. And if you think it’s worth the money, purchase the license with **ITSFOSS25** coupon code. + +You can download Insync from their website. + +I have used Insync from the time when it was available for free and I have always liked it. They have added more features over the time and improved its UI and performance. Overall, it’s a nice-to-have application if you use Google Drive a lot and do not mind paying for the efforts of the developers. + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/insync-linux-review/ + +作者：[Abhishek Prakash][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/abhishek/ +[b]: https://github.com/lujun9972 +[1]: https://abevoelker.github.io/how-long-since-google-said-a-google-drive-linux-client-is-coming/ +[2]: https://itsfoss.com/use-google-drive-linux/ +[3]: https://www.insynchq.com +[4]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/12/google-drive-linux-insync.jpeg?resize=800%2C450&ssl=1 +[5]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_interface.jpeg?fit=800%2C501&ssl=1 +[6]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_multiple_google_account.jpeg?ssl=1 +[7]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_folder_settings.png?ssl=1 +[8]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_selective_sync.png?ssl=1 +[9]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_file_matching.jpeg?ssl=1 +[10]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_ignore_list_1.png?ssl=1 +[11]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/11/add-to-insync-shortcut.jpeg?ssl=1 +[12]: https://help.insynchq.com/key-features-and-syncing-explained/syncing-superpowers/using-symlinks-on-google-drive-with-insync +[13]: https://www.insynchq.com/downloads +[14]: https://en.wikipedia.org/wiki/Headless_software +[15]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/11/insync_cli.jpeg?fit=800%2C478&ssl=1 +[16]: https://help.insynchq.com/installation-on-windows-linux-and-macos/advanced/linux-controlling-insync-via-command-line-cli +[17]: https://www.insynchq.com/pricing +[18]: https://gsuite.google.com/learning-center/products/drive/get-started-team-drive/#!/ diff --git a/sources/tech/20181218 Termtosvg - Record Your Terminal Sessions As SVG Animations In Linux.md b/sources/tech/20181218 Termtosvg - Record Your Terminal Sessions As SVG Animations In Linux.md new file mode 100644 index 0000000000..f25406a66a --- /dev/null +++ b/sources/tech/20181218 Termtosvg - Record Your Terminal Sessions As SVG Animations In Linux.md @@ -0,0 +1,170 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Termtosvg – Record Your Terminal Sessions As SVG Animations In Linux) +[#]: via: (https://www.2daygeek.com/termtosvg-record-your-terminal-sessions-as-svg-animations-in-linux/) +[#]: author: (Magesh Maruthamuthu https://www.2daygeek.com/author/magesh/) + +Termtosvg – Record Your Terminal Sessions As SVG Animations In Linux +====== + +By default everyone prefer history command to review/recall the previously entered commands in terminal. + +But unfortunately, that shows only the commands that we ran and doesn’t shows the commands output which was performed previously. + +There are many utilities available in Linux to record the terminal session activity. + +This tool will help us to record the users terminal activity, also will help us to identify other useful information from the output. + +Also, we had written about few utilities in the past and today also we are going to discuss about the same kind of topic. + +If you would like to check other utilities to record your Linux terminal session activity then you can give a try to **[Script Command][1]** and **[Terminalizer Tool][2]**. + +But if you are looking for **[GIF Recorder][3]** then try **[Gifine][4]** , **[Kgif][5]** and **[Peek][6]** utilities. + +Script is one of the best utility to record your terminal session on headless server. + +Script is a Unix command line utility that records a terminal session (in other terms, It’s record everything displayed on your terminal). + +It stores the output in the current directory as a text file and the default file name is typescript. + +### What is Termtosvg + +Termtosvg is a Unix terminal recorder written in Python that renders your command line sessions as standalone SVG animations. + +### Termtosvg Features + + * Produce lightweight and clean looking animations embeddable on a project page. + * Custom color themes, terminal UI and animation controls via SVG templates. + * Compatible with asciinema recording format. + * It requires Python >= 3.5 + + + +### How to Install Termtosvg In Linux + +It was written in Python and pip installation is a recommended method to install Termtosvg on Linux. + +Make sure you should have installed python-pip package on your system. If no, use the following command to install it. + +For Debian/Ubuntu users, use **[Apt Command][7]** or **[Apt-Get Command][8]** to install pip package. + +``` +$ sudo apt install python-pip +``` + +For Archlinux users, use **[Pacman Command][9]** to install pip package. + +``` +$ sudo pacman -S python-pip +``` + +For Fedora users, use **[DNF Command][10]** to install pip package. + +``` +$ sudo dnf install python-pip +``` + +For CentOS/RHEL users, use **[YUM Command][11]** to install pip package. + +``` +$ sudo yum install python-pip +``` + +For openSUSE users, use **[Zypper Command][12]** to install pip package. + +``` +$ sudo zypper install python-pip +``` + +Finally run the following **[pip command][13]** to install Termtosvg tool in Linux. + +``` +$ sudo pip3 install termtosvg pyte python-xlib svgwrite +``` + +### How to Record Your Terminal Session Using Termtosvg + +Once you successfully installed Termtosvg. Just run the following command to start recording. + +``` +$ termtosvg +Recording started, enter "exit" command or Control-D to end +``` + +For testing purpose run few commands and see whether it’s working fine or not. + +``` +$ uname -a +Linux daygeek-Y700 4.19.8-2-MANJARO #1 SMP PREEMPT Sat Dec 8 14:45:36 UTC 2018 x86_64 GNU/Linux +$ hostname +daygeek-Y700 +$ cat /etc/*-release +Manjaro Linux +DISTRIB_ID=ManjaroLinux +DISTRIB_RELEASE=18.0 +DISTRIB_CODENAME=Illyria +DISTRIB_DESCRIPTION="Manjaro Linux" +Manjaro Linux +NAME="Manjaro Linux" +ID=manjaro +ID_LIKE=arch +PRETTY_NAME="Manjaro Linux" +ANSI_COLOR="1;32" +HOME_URL="https://www.manjaro.org/" +SUPPORT_URL="https://www.manjaro.org/" +BUG_REPORT_URL="https://bugs.manjaro.org/" +$ free -g +free: Multiple unit options doesn't make sense. +$ free -m +free: Multiple unit options doesn't make sense. +$ pip3 --version +pip 18.1 from /usr/lib/python3.7/site-packages/pip (python 3.7) +``` + +Once you have done, simple press `CTRL+D` or type `exit` to stop the recording. The result will be saved in `/tmp` folder with a unique name. + +``` +$ exit +exit +Recording ended, SVG animation is /tmp/termtosvg_5waorper.svg +``` + +We can open the SVG file output with help of any web browser. + +``` +$ firefox /tmp/termtosvg_5waorper.svg +``` + +![][15] + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/termtosvg-record-your-terminal-sessions-as-svg-animations-in-linux/ + +作者：[Magesh Maruthamuthu][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/magesh/ +[b]: https://github.com/lujun9972 +[1]: https://www.2daygeek.com/script-command-record-save-your-terminal-session-activity-linux/ +[2]: https://www.2daygeek.com/terminalizer-a-tool-to-record-your-terminal-and-generate-animated-gif-images/ +[3]: https://www.2daygeek.com/category/gif-recorder/ +[4]: https://www.2daygeek.com/gifine-create-animated-gif-vedio-recorder-linux-mint-debian-ubuntu/ +[5]: https://www.2daygeek.com/kgif-create-animated-gif-file-active-window-screen-recorder-capture-arch-linux-mint-fedora-ubuntu-debian-opensuse-centos/ +[6]: https://www.2daygeek.com/peek-create-animated-gif-screen-recorder-capture-arch-linux-mint-fedora-ubuntu/ +[7]: https://www.2daygeek.com/apt-command-examples-manage-packages-debian-ubuntu-systems/ +[8]: https://www.2daygeek.com/apt-get-apt-cache-command-examples-manage-packages-debian-ubuntu-systems/ +[9]: https://www.2daygeek.com/pacman-command-examples-manage-packages-arch-linux-system/ +[10]: https://www.2daygeek.com/dnf-command-examples-manage-packages-fedora-system/ +[11]: https://www.2daygeek.com/yum-command-examples-manage-packages-rhel-centos-systems/ +[12]: https://www.2daygeek.com/zypper-command-examples-manage-packages-opensuse-system/ +[13]: https://www.2daygeek.com/install-pip-manage-python-packages-linux/ +[14]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[15]: https://www.2daygeek.com/wp-content/uploads/2018/12/Termtosvg-Record-Your-Terminal-Sessions-As-SVG-Animations-In-Linux-1.gif diff --git a/sources/tech/20181218 Use your Linux terminal to celebrate a banner year.md b/sources/tech/20181218 Use your Linux terminal to celebrate a banner year.md new file mode 100644 index 0000000000..da3f36b00f --- /dev/null +++ b/sources/tech/20181218 Use your Linux terminal to celebrate a banner year.md @@ -0,0 +1,100 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Use your Linux terminal to celebrate a banner year) +[#]: via: (https://opensource.com/article/18/12/linux-toy-figlet) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Use your Linux terminal to celebrate a banner year +====== +Need make sure your command is heard? Pipe it to a banner and it won't be missed. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-figlet.png?itok=o4XmTL-b) + + +Hello again for another installment in our 24-day-long Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is. We’re figuring that out as we go, but generally, it could be a game, or any simple diversion that helps you have fun at the terminal. + +Some of you will have seen various selections from our calendar before, but we hope there’s at least one new thing for everyone. + +Today's toy if **figlet** , a utility for printing text in banner form across your Linux terminal. + +You'll likely find **figlet** packaged in your standard repositories. For me on Fedora, this meant installation was as simple as: + +``` +$ sudo dnf install figlet +``` + +After that, simply use the program's name to invoke it. You can either use it interactively, or, pipe some text to it, as below: + +``` +echo "Hello world" | figlet + _   _      _ _                            _     _ +| | | | ___| | | ___   __      _____  _ __| | __| | +| |_| |/ _ \ | |/ _ \  \ \ /\ / / _ \| '__| |/ _` | +|  _  |  __/ | | (_) |  \ V  V / (_) | |  | | (_| | +|_| |_|\___|_|_|\___/    \_/\_/ \___/|_|  |_|\__,_| +``` + +There are a number of different font options available for **figlet**. To see the options available to you, try the command **showfigfonts**. For me, this displayed over a dozen. I've copied out a few of my favorites below. + +``` +block : +                                            +_|        _|                      _|         +_|_|_|    _|    _|_|      _|_|_|  _|  _|     +_|    _|  _|  _|    _|  _|        _|_|       +_|    _|  _|  _|    _|  _|        _|  _|     +_|_|_|    _|    _|_|      _|_|_|  _|    _|   + + +bubble : +  _   _   _   _   _   _   + / \ / \ / \ / \ / \ / \ +( b | u | b | b | l | e ) + \_/ \_/ \_/ \_/ \_/ \_/ + + +lean : +                                      +    _/                               +   _/    _/_/      _/_/_/  _/_/_/     +  _/  _/_/_/_/  _/    _/  _/    _/   + _/  _/        _/    _/  _/    _/     +_/    _/_/_/    _/_/_/  _/    _/   + + +script : +                          +               o           + ,   __   ,_        _ _|_ +/ \_/    /  |  |  |/ \_|   + \/ \___/   |_/|_/|__/ |_/ +                 /|       +                 \|       +``` + +You can find out more about **figlet** on the project's [homepage][1]. The version I downloaded was made available as open source under an MIT license. + +You'll find that **figlet** isn't the only banner-printer available for the Linux terminal. Another option that you may choose to check out is [toilet][2], which comes with its own set of ASCII-art style printing options. + +Do you have a favorite command-line toy that you we should have included? Our calendar is basically set for the remainder of the series, but we'd still love to feature some cool command-line toys in the new year. Let me know in the comments below, and I'll check it out. And let me know what you thought of today's amusement. + +Be sure to check out yesterday's toy, [Take a swim at your Linux terminal with asciiquarium][3], and come back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-figlet + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: http://www.figlet.org/ +[2]: http://caca.zoy.org/wiki/toilet +[3]: https://opensource.com/article/18/12/linux-toy-asciiquarium diff --git a/sources/tech/20181219 How to open source your Python library.md b/sources/tech/20181219 How to open source your Python library.md new file mode 100644 index 0000000000..e4d6adf3c6 --- /dev/null +++ b/sources/tech/20181219 How to open source your Python library.md @@ -0,0 +1,114 @@ +[#]: collector: (lujun9972) +[#]: translator: (HankChow) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (How to open source your Python library) +[#]: via: (https://opensource.com/article/18/12/tips-open-sourcing-python-libraries) +[#]: author: (Moshe Zadka https://opensource.com/users/moshez) + +How to open source your Python library +====== +This 12-step checklist will ensure a successful launch. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/button_push_open_keyboard_file_organize.png?itok=KlAsk1gx) + +You wrote a Python library. I'm sure it's amazing! Wouldn't it be neat if it was easy for people to use it? Here is a checklist of things to think about and concrete steps to take when open sourcing your Python library. + +### 1\. Source + +Put the code up on [GitHub][1], where most open source projects happen and where it is easiest for people to submit pull requests. + +### 2\. License + +Choose an open source license. A good, permissive default is the [MIT License][2]. If you have specific requirements, Creative Common's [Choose a License][3] can guide you through the alternatives. Most importantly, there are three rules to keep in mind when choosing a license: + + * Don't create your own license. + * Don't create your own license. + * Don't create your own license. + + + +### 3\. README + +Put a file called README.rst, formatted with ReStructured Text, at the top of your tree. + +GitHub will render ReStructured Text just as well as Markdown, and ReST plays better with Python's documentation ecosystem. + +### 4\. Tests + +Write tests. This is not useful just for you: it is useful for people who want to make patches that avoid breaking related functionality. + +Tests help collaborators collaborate. + +Usually, it is best if they are runnable with [**pytest**][4]. There are other test runners—but very little reason to use them. + +### 5\. Style + +Enforce style with a linter: PyLint, Flake8, or Black with **\--check**. Unless you use Black, make sure to specify configuration options in a file checked into source control. + +### 6\. API documentation + +Use docstrings to document modules, functions, classes, and methods. + +There are a few styles you can use. I prefer the [Google-style docstrings][5], but [ReST docstrings][6] are an option. + +Both Google-style and ReST docstrings can be processed by Sphinx to integrate API documentation with prose documentation. + +### 7\. Prose documentation + +Use [Sphinx][7]. (Read [our article on it][8].) A tutorial is useful, but it is also important to specify what this thing is, what it is good for, what it is bad for, and any special considerations. + +### 8\. Building + +Use **tox** or **nox** to automatically run your tests and linter and build the documentation. These tools support a "dependency matrix." These matrices tend to explode fast, but try to test against a reasonable sample, such as Python versions, versions of dependencies, and possibly optional dependencies you install. + +### 9\. Packaging + +Use [setuptools][9]. Write a **setup.py** and a **setup.cfg**. If you support both Python 2 and 3, specify universal wheels in the **setup.cfg**. + +One thing **tox** or **nox** should do is build a wheel and run tests against the installed wheel. + +Avoid C extensions. If you absolutely need them for performance or binding reasons, put them in a separate package. Properly packaging C extensions deserves its own post. There are a lot of gotchas! + +### 10\. Continuous integration + +### 11\. Versions + +Use a public continuous integration runner. [TravisCI][10] and [CircleCI][11] offer free tiers for open source projects. Configure GitHub or other repo to require passing checks before merging pull requests, and you'll never have to worry about telling people to fix their tests or their style in code reviews. + +Use either [SemVer][12] or [CalVer][13]. There are many tools to help manage versions: [incremental][14], [bumpversion][15], and [setuptools_scm][16] are all packages on PyPI that help manage versions for you. + +### 12\. Release + +Release by running **tox** or **nox** and using **twine** to upload the artifacts to PyPI. You can do a "test upload" by running [DevPI][17]. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/tips-open-sourcing-python-libraries + +作者：[Moshe Zadka][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/moshez +[b]: https://github.com/lujun9972 +[1]: https://github.com/ +[2]: https://en.wikipedia.org/wiki/MIT_License +[3]: https://choosealicense.com/ +[4]: https://docs.pytest.org/en/latest/ +[5]: https://github.com/google/styleguide/blob/gh-pages/pyguide.md +[6]: https://www.python.org/dev/peps/pep-0287/ +[7]: http://www.sphinx-doc.org/en/master/ +[8]: https://opensource.com/article/18/11/building-custom-workflows-sphinx +[9]: https://pypi.org/project/setuptools/ +[10]: https://travis-ci.org/ +[11]: https://circleci.com/ +[12]: https://semver.org/ +[13]: https://calver.org/ +[14]: https://pypi.org/project/incremental/ +[15]: https://pypi.org/project/bumpversion/ +[16]: https://pypi.org/project/setuptools_scm/ +[17]: https://opensource.com/article/18/7/setting-devpi diff --git a/sources/tech/20181219 PowerTOP - Monitors Power Usage and Improve Laptop Battery Life in Linux.md b/sources/tech/20181219 PowerTOP - Monitors Power Usage and Improve Laptop Battery Life in Linux.md new file mode 100644 index 0000000000..a615ffc73a --- /dev/null +++ b/sources/tech/20181219 PowerTOP - Monitors Power Usage and Improve Laptop Battery Life in Linux.md @@ -0,0 +1,411 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (PowerTOP – Monitors Power Usage and Improve Laptop Battery Life in Linux) +[#]: via: (https://www.2daygeek.com/powertop-monitors-laptop-battery-usage-linux/) +[#]: author: (Vinoth Kumar https://www.2daygeek.com/author/vinoth/) + +PowerTOP – Monitors Power Usage and Improve Laptop Battery Life in Linux +====== + +We all know, we almost 80-90% migrated from PC (Desktop) to laptop. + +But one thing we want from a laptop, it’s long battery life and we want to use every drop of power. + +So it’s good to know where our power is going and getting waste. + +You can use the powertop utility to see what’s drawing power when your system’s not plugged in. + +You need to run the powertop utility in terminal with super user privilege. + +It will access the hardware and measure power usage. + +### What is PowerTOP + +PowerTOP is a Linux tool to diagnose issues with power consumption and power management. + +It was developed by Intel to enable various power-saving modes in kernel, userspace, and hardware. + +In addition to being a diagnostic tool, PowerTOP also has an interactive mode where the user can experiment various power management settings for cases where the Linux distribution has not enabled these settings. + +It is possible to monitor processes and show which of them are utilizing the CPU and wake it from its Idle-States, allowing to identify applications with particular high power demands. + +### How to Install PowerTOP + +PowerTOP package is available in most of the distributions official repository so, use the distributions **[Package Manager][1]** to install it. + +For **`Fedora`** system, use **[DNF Command][2]** to install PowerTOP. + +``` +$ sudo dnf install powertop +``` + +For **`Debian/Ubuntu`** systems, use **[APT-GET Command][3]** or **[APT Command][4]** to install PowerTOP. + +``` +$ sudo apt install powertop +``` + +For **`Arch Linux`** based systems, use **[Pacman Command][5]** to install PowerTOP. + +``` +$ sudo pacman -S powertop +``` + +For **`RHEL/CentOS`** systems, use **[YUM Command][6]** to install PowerTOP. + +``` +$ sudo yum install powertop +``` + +For **`openSUSE Leap`** system, use **[Zypper Command][7]** to install PowerTOP. + +``` +$ sudo zypper install powertop +``` + +### How To Access PowerTOP + +PowerTOP requires super user privilege so, run as root to use PowerTOP utility on your Linux system. + +By default it shows `Overview` tab where we can see the power usage consumption for all the devices. Also shows your system wakeups seconds. + +``` +$ sudo powertop + +PowerTOP v2.9 Overview Idle stats Frequency stats Device stats Tunables + +The battery reports a discharge rate of 12.6 W +The power consumed was 259 J +The estimated remaining time is 1 hours, 52 minutes + +Summary: 1692.9 wakeups/second, 0.0 GPU ops/seconds, 0.0 VFS ops/sec and 54.9% CPU use + + Usage Events/s Category Description + 9.3 ms/s 529.4 Timer tick_sched_timer + 378.5 ms/s 139.8 Process [PID 2991] /usr/lib/firefox/firefox -contentproc -childID 7 -isForBrowser -prefsLen 8314 -prefMapSize 173895 -schedulerPrefs 00 + 7.5 ms/s 141.7 Timer hrtimer_wakeup + 3.3 ms/s 102.7 Process [PID 1527] /usr/lib/firefox/firefox --new-window + 11.6 ms/s 69.1 Process [PID 1568] /usr/lib/firefox/firefox -contentproc -childID 1 -isForBrowser -prefsLen 1 -prefMapSize 173895 -schedulerPrefs 0001, + 6.2 ms/s 59.0 Process [PID 1496] /usr/lib/firefox/firefox --new-window + 2.1 ms/s 59.6 Process [PID 2466] /usr/lib/firefox/firefox -contentproc -childID 3 -isForBrowser -prefsLen 5814 -prefMapSize 173895 -schedulerPrefs 00 + 1.8 ms/s 52.3 Process [PID 2052] /usr/lib/firefox/firefox -contentproc -childID 4 -isForBrowser -prefsLen 5814 -prefMapSize 173895 -schedulerPrefs 00 + 1.8 ms/s 50.8 Process [PID 3034] /usr/lib/firefox/firefox -contentproc -childID 7 -isForBrowser -prefsLen 8314 -prefMapSize 173895 -schedulerPrefs 00 + 3.6 ms/s 48.4 Process [PID 3009] /usr/lib/firefox/firefox -contentproc -childID 7 -isForBrowser -prefsLen 8314 -prefMapSize 173895 -schedulerPrefs 00 + 7.5 ms/s 46.2 Process [PID 2996] /usr/lib/firefox/firefox -contentproc -childID 7 -isForBrowser -prefsLen 8314 -prefMapSize 173895 -schedulerPrefs 00 + 25.2 ms/s 33.6 Process [PID 1528] /usr/lib/firefox/firefox --new-window + 5.7 ms/s 32.2 Interrupt [7] sched(softirq) + 2.1 ms/s 32.2 Process [PID 1811] /usr/lib/firefox/firefox -contentproc -childID 4 -isForBrowser -prefsLen 5814 -prefMapSize 173895 -schedulerPrefs 00 + 19.7 ms/s 25.0 Process [PID 1794] /usr/lib/firefox/firefox -contentproc -childID 4 -isForBrowser -prefsLen 5814 -prefMapSize 173895 -schedulerPrefs 00 + 1.9 ms/s 31.5 Process [PID 1596] /usr/lib/firefox/firefox -contentproc -childID 1 -isForBrowser -prefsLen 1 -prefMapSize 173895 -schedulerPrefs 0001, + 3.1 ms/s 29.9 Process [PID 1535] /usr/lib/firefox/firefox --new-window + 7.1 ms/s 28.2 Process [PID 1488] /usr/lib/firefox/firefox --new-window + 1.8 ms/s 29.5 Process [PID 1762] /usr/lib/firefox/firefox -contentproc -childID 3 -isForBrowser -prefsLen 5814 -prefMapSize 173895 -schedulerPrefs 00 + 8.8 ms/s 23.3 Process [PID 1121] /usr/bin/gnome-shell + 1.2 ms/s 21.8 Process [PID 1657] /usr/lib/firefox/firefox -contentproc -childID 2 -isForBrowser -prefsLen 920 -prefMapSize 173895 -schedulerPrefs 000 + 13.3 ms/s 13.9 Process [PID 1746] /usr/lib/firefox/firefox -contentproc -childID 3 -isForBrowser -prefsLen 5814 -prefMapSize 173895 -schedulerPrefs 00 + 2.7 ms/s 11.1 Process [PID 3410] /usr/lib/gnome-terminal-server + 3.8 ms/s 10.8 Process [PID 1057] /usr/lib/Xorg vt2 -displayfd 3 -auth /run/user/1000/gdm/Xauthority -nolisten tcp -background none -noreset -keeptty + 3.1 ms/s 9.8 Process [PID 1629] /usr/lib/firefox/firefox -contentproc -childID 2 -isForBrowser -prefsLen 920 -prefMapSize 173895 -schedulerPrefs 000 + 0.9 ms/s 6.7 Interrupt [136] xhci_hcd + 278.0 us/s 6.4 Process [PID 414] [irq/141-iwlwifi] + 128.7 us/s 5.7 Process [PID 1] /sbin/init + 118.5 us/s 5.2 Process [PID 10] [rcu_preempt] + 49.0 us/s 4.7 Interrupt [0] HI_SOFTIRQ + 459.3 us/s 3.1 Interrupt [142] i915 + 2.1 ms/s 2.3 Process [PID 3451] powertop + 8.4 us/s 2.7 kWork intel_atomic_helper_free_state_ + 1.2 ms/s 1.8 kWork intel_atomic_commit_work + 374.2 us/s 2.1 Interrupt [9] acpi + 42.1 us/s 1.8 kWork intel_atomic_cleanup_work + 3.5 ms/s 0.25 kWork delayed_fput + 238.0 us/s 1.5 Process [PID 907] /usr/lib/upowerd + 17.7 us/s 1.5 Timer intel_uncore_fw_release_timer + 26.4 us/s 1.4 Process [PID 576] [i915/signal:0] + 19.8 us/s 1.3 Timer watchdog_timer_fn + 1.1 ms/s 0.00 Process [PID 206] [kworker/7:2] + 2.4 ms/s 0.00 Interrupt [1] timer(softirq) + 13.4 us/s 0.9 Process [PID 9] [ksoftirqd/0] + + Exit | / Navigate | +``` + +The powertop output looks similar to the above screenshot, it will be slightly different based on your hardware. This have many screen you can switch between screen the using `Tab` and `Shift+Tab` button. + +### Idle Stats Tab + +It displays various information about the processor. + +``` +PowerTOP v2.9 Overview Idle stats Frequency stats Device stats Tunables + + + Package | Core | CPU 0 CPU 4 + | | C0 active 6.7% 7.2% + | | POLL 0.0% 0.1 ms 0.0% 0.1 ms + | | C1E 1.2% 0.2 ms 1.6% 0.3 ms +C2 (pc2) 7.5% | | +C3 (pc3) 25.2% | C3 (cc3) 0.7% | C3 0.5% 0.2 ms 0.6% 0.1 ms +C6 (pc6) 0.0% | C6 (cc6) 7.1% | C6 6.6% 0.5 ms 6.3% 0.5 ms +C7 (pc7) 0.0% | C7 (cc7) 59.8% | C7s 0.0% 0.0 ms 0.0% 0.0 ms +C8 (pc8) 0.0% | | C8 33.9% 1.6 ms 32.3% 1.5 ms +C9 (pc9) 0.0% | | C9 2.1% 3.4 ms 0.7% 2.8 ms +C10 (pc10) 0.0% | | C10 39.5% 4.7 ms 41.4% 4.7 ms + + | Core | CPU 1 CPU 5 + | | C0 active 8.3% 7.2% + | | POLL 0.0% 0.0 ms 0.0% 0.1 ms + | | C1E 1.3% 0.2 ms 1.4% 0.3 ms + | | + | C3 (cc3) 0.5% | C3 0.5% 0.2 ms 0.4% 0.2 ms + | C6 (cc6) 6.0% | C6 5.3% 0.5 ms 4.7% 0.5 ms + | C7 (cc7) 59.3% | C7s 0.0% 0.8 ms 0.0% 1.0 ms + | | C8 27.2% 1.5 ms 23.8% 1.4 ms + | | C9 1.6% 3.0 ms 0.5% 3.0 ms + | | C10 44.5% 4.7 ms 52.2% 4.6 ms + + | Core | CPU 2 CPU 6 + | | C0 active 11.2% 8.4% + | | POLL 0.0% 0.0 ms 0.0% 0.0 ms + | | C1E 1.4% 0.4 ms 1.3% 0.3 ms + | | + | C3 (cc3) 0.3% | C3 0.2% 0.1 ms 0.4% 0.2 ms + | C6 (cc6) 4.0% | C6 3.7% 0.5 ms 4.3% 0.5 ms + | C7 (cc7) 54.2% | C7s 0.0% 0.0 ms 0.0% 1.0 ms + | | C8 20.0% 1.5 ms 20.7% 1.4 ms + | | C9 1.0% 3.4 ms 0.4% 3.8 ms + | | C10 48.8% 4.6 ms 52.3% 5.0 ms + + | Core | CPU 3 CPU 7 + | | C0 active 8.8% 8.1% + | | POLL 0.0% 0.1 ms 0.0% 0.0 ms + | | C1E 1.2% 0.2 ms 1.2% 0.2 ms + | | + | C3 (cc3) 0.6% | C3 0.6% 0.2 ms 0.4% 0.2 ms + | C6 (cc6) 7.0% | C6 7.5% 0.5 ms 4.4% 0.5 ms + | C7 (cc7) 56.8% | C7s 0.0% 0.0 ms 0.0% 0.9 ms + | | C8 29.4% 1.4 ms 23.8% 1.4 ms + | | C9 1.1% 2.7 ms 0.7% 3.9 ms + | | C10 41.0% 4.0 ms 50.0% 4.8 ms + + + Exit | / Navigate | +``` + +### Frequency Stats Tab + +It displays the frequency of CPU. + +``` +PowerTOP v2.9 Overview Idle stats Frequency stats Device stats Tunables + + + Package | Core | CPU 0 CPU 4 + | | Average 930 MHz 1101 MHz +Idle | Idle | Idle + + | Core | CPU 1 CPU 5 + | | Average 1063 MHz 979 MHz + | Idle | Idle + + | Core | CPU 2 CPU 6 + | | Average 976 MHz 942 MHz + | Idle | Idle + + | Core | CPU 3 CPU 7 + | | Average 924 MHz 957 MHz + | Idle | Idle + +``` + +### Device Stats Tab + +It displays power usage information against only devices. + +``` +PowerTOP v2.9 Overview Idle stats Frequency stats Device stats Tunables + + +The battery reports a discharge rate of 13.8 W +The power consumed was 280 J + + Usage Device name + 46.7% CPU misc + 46.7% DRAM + 46.7% CPU core + 19.0% Display backlight + 0.0% Audio codec hwC0D0: Realtek + 0.0% USB device: Lenovo EasyCamera (160709000341) + 100.0% PCI Device: Intel Corporation HD Graphics 530 + 100.0% Radio device: iwlwifi + 100.0% PCI Device: O2 Micro, Inc. SD/MMC Card Reader Controller + 100.0% PCI Device: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers + 100.0% USB device: Lenovo Wireless Optical Mouse N100 + 100.0% PCI Device: Intel Corporation Wireless 8260 + 100.0% PCI Device: Intel Corporation HM170/QM170 Chipset SATA Controller [AHCI Mode] + 100.0% Radio device: btusb + 100.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #4 + 100.0% USB device: xHCI Host Controller + 100.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family USB 3.0 xHCI Controller + 100.0% PCI Device: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller + 100.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #3 + 100.0% PCI Device: Samsung Electronics Co Ltd NVMe SSD Controller SM951/PM951 + 100.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #2 + 100.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #9 + 100.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family SMBus + 26.1 pkts/s Network interface: wlp8s0 (iwlwifi) + 0.0% USB device: usb-device-8087-0a2b + 0.0% runtime-reg-dummy + 0.0% Audio codec hwC0D2: Intel + 0.0 pkts/s Network interface: enp9s0 (r8168) + 0.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family Power Management Controller + 0.0% PCI Device: Intel Corporation HM170 Chipset LPC/eSPI Controller + 0.0% PCI Device: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor PCIe Controller (x16) + 0.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family MEI Controller #1 + 0.0% PCI Device: NVIDIA Corporation GM107M [GeForce GTX 960M] + 0.0% I2C Adapter (i2c-8): nvkm-0000:01:00.0-bus-0005 + 0.0% runtime-PNP0C14:00 + 0.0% PCI Device: Intel Corporation 100 Series/C230 Series Chipset Family HD Audio Controller + 0.0% runtime-PNP0C0C:00 + 0.0% USB device: xHCI Host Controller + 0.0% runtime-ACPI000C:00 + 0.0% runtime-regulatory.0 + 0.0% runtime-PNP0C14:01 + 0.0% runtime-vesa-framebuffer.0 + 0.0% runtime-coretemp.0 + 0.0% runtime-alarmtimer + + Exit | / Navigate | +``` + +### Tunables Stats Tab + +This tab is important area that provides suggestions to optimize your laptop battery. + +``` +PowerTOP v2.9 Overview Idle stats Frequency stats Device stats Tunables + + +>> Bad Enable SATA link power management for host2 + Bad Enable SATA link power management for host3 + Bad Enable SATA link power management for host0 + Bad Enable SATA link power management for host1 + Bad VM writeback timeout + Bad Autosuspend for USB device Lenovo Wireless Optical Mouse N100 [1-2] + Good Bluetooth device interface status + Good Enable Audio codec power management + Good NMI watchdog should be turned off + Good Runtime PM for I2C Adapter i2c-7 (nvkm-0000:01:00.0-bus-0002) + Good Autosuspend for unknown USB device 1-11 (8087:0a2b) + Good Runtime PM for I2C Adapter i2c-3 (i915 gmbus dpd) + Good Autosuspend for USB device Lenovo EasyCamera [160709000341] + Good Runtime PM for I2C Adapter i2c-1 (i915 gmbus dpc) + Good Runtime PM for I2C Adapter i2c-12 (nvkm-0000:01:00.0-bus-0009) + Good Autosuspend for USB device xHCI Host Controller [usb1] + Good Runtime PM for I2C Adapter i2c-13 (nvkm-0000:01:00.0-aux-000a) + Good Runtime PM for I2C Adapter i2c-2 (i915 gmbus dpb) + Good Runtime PM for I2C Adapter i2c-8 (nvkm-0000:01:00.0-bus-0005) + Good Runtime PM for I2C Adapter i2c-15 (nvkm-0000:01:00.0-aux-000c) + Good Runtime PM for I2C Adapter i2c-16 (nvkm-0000:01:00.0-aux-000d) + Good Runtime PM for I2C Adapter i2c-5 (nvkm-0000:01:00.0-bus-0000) + Good Runtime PM for I2C Adapter i2c-0 (SMBus I801 adapter at 6040) + Good Runtime PM for I2C Adapter i2c-11 (nvkm-0000:01:00.0-bus-0008) + Good Runtime PM for I2C Adapter i2c-14 (nvkm-0000:01:00.0-aux-000b) + Good Autosuspend for USB device xHCI Host Controller [usb2] + Good Runtime PM for I2C Adapter i2c-9 (nvkm-0000:01:00.0-bus-0006) + Good Runtime PM for I2C Adapter i2c-10 (nvkm-0000:01:00.0-bus-0007) + Good Runtime PM for I2C Adapter i2c-6 (nvkm-0000:01:00.0-bus-0001) + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family HD Audio Controller + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family USB 3.0 xHCI Controller + Good Runtime PM for PCI Device Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #9 + Good Runtime PM for PCI Device Intel Corporation HD Graphics 530 + Good Runtime PM for PCI Device Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #3 + Good Runtime PM for PCI Device O2 Micro, Inc. SD/MMC Card Reader Controller + Good Runtime PM for PCI Device Intel Corporation HM170 Chipset LPC/eSPI Controller + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family MEI Controller #1 + Good Runtime PM for PCI Device Samsung Electronics Co Ltd NVMe SSD Controller SM951/PM951 + Good Runtime PM for PCI Device Intel Corporation HM170/QM170 Chipset SATA Controller [AHCI Mode] + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family Power Management Controller + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #2 + Good Runtime PM for PCI Device Intel Corporation Wireless 8260 + Good Runtime PM for PCI Device Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor PCIe Controller (x16) + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #4 + Good Runtime PM for PCI Device Intel Corporation 100 Series/C230 Series Chipset Family SMBus + Good Runtime PM for PCI Device NVIDIA Corporation GM107M [GeForce GTX 960M] + + Exit | Toggle tunable | Window refresh +``` + +### How To Generate PowerTop HTML Report + +Run the following command to generate the PowerTop HTML report. + +``` +$ sudo powertop --html=powertop.html +modprobe cpufreq_stats failedLoaded 100 prior measurements +Cannot load from file /var/cache/powertop/saved_parameters.powertop +File will be loaded after taking minimum number of measurement(s) with battery only +RAPL device for cpu 0 +RAPL Using PowerCap Sysfs : Domain Mask f +RAPL device for cpu 0 +RAPL Using PowerCap Sysfs : Domain Mask f +Devfreq not enabled +glob returned GLOB_ABORTED +Cannot load from file /var/cache/powertop/saved_parameters.powertop +File will be loaded after taking minimum number of measurement(s) with battery only +Preparing to take measurements +To show power estimates do 182 measurement(s) connected to battery only +Taking 1 measurement(s) for a duration of 20 second(s) each. +PowerTOP outputing using base filename powertop.html +``` + +Navigate to `file:///home/daygeek/powertop.html` file to access the generated PowerTOP HTML report. +![][9] + +### Auto-Tune mode + +This feature sets all tunable options from `BAD` to `GOOD` which increase the laptop battery life in Linux. + +``` +$ sudo powertop --auto-tune +modprobe cpufreq_stats failedLoaded 210 prior measurements +Cannot load from file /var/cache/powertop/saved_parameters.powertop +File will be loaded after taking minimum number of measurement(s) with battery only +RAPL device for cpu 0 +RAPL Using PowerCap Sysfs : Domain Mask f +RAPL device for cpu 0 +RAPL Using PowerCap Sysfs : Domain Mask f +Devfreq not enabled +glob returned GLOB_ABORTED +Cannot load from file /var/cache/powertop/saved_parameters.powertop +File will be loaded after taking minimum number of measurement(s) with battery only +To show power estimates do 72 measurement(s) connected to battery only +Leaving PowerTOP +``` + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/powertop-monitors-laptop-battery-usage-linux/ + +作者：[Vinoth Kumar][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/vinoth/ +[b]: https://github.com/lujun9972 +[1]: https://www.2daygeek.com/category/package-management/ +[2]: https://www.2daygeek.com/dnf-command-examples-manage-packages-fedora-system/ +[3]: https://www.2daygeek.com/apt-get-apt-cache-command-examples-manage-packages-debian-ubuntu-systems/ +[4]: https://www.2daygeek.com/apt-command-examples-manage-packages-debian-ubuntu-systems/ +[5]: https://www.2daygeek.com/pacman-command-examples-manage-packages-arch-linux-system/ +[6]: https://www.2daygeek.com/yum-command-examples-manage-packages-rhel-centos-systems/ +[7]: https://www.2daygeek.com/zypper-command-examples-manage-packages-opensuse-system/ +[8]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[9]: https://www.2daygeek.com/wp-content/uploads/2015/07/powertop-html-output.jpg diff --git a/sources/tech/20181219 Solve a puzzle at the Linux command line with nudoku.md b/sources/tech/20181219 Solve a puzzle at the Linux command line with nudoku.md new file mode 100644 index 0000000000..7822a0cb98 --- /dev/null +++ b/sources/tech/20181219 Solve a puzzle at the Linux command line with nudoku.md @@ -0,0 +1,54 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Solve a puzzle at the Linux command line with nudoku) +[#]: via: (https://opensource.com/article/18/12/linux-toy-nudoku) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Solve a puzzle at the Linux command line with nudoku +====== +Sudokus are simple logic games that can be enjoyed just about anywhere, including in your Linux terminal. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-nudoku.png?itok=OS2o4Rot) + +Welcome back to another installment in our 24-day-long Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is. We’re figuring that out as we go, but generally, it could be a game, or any simple diversion that helps you have fun at the terminal. + +Some of you will have seen various selections from our calendar before, but we hope there’s at least one new thing for everyone. + +Every year for Christmas, my mother-in-law gives my wife a Sudoku calendar. It sits on our coffee table for the year to follow. Each day is a separate sheet (except for Saturday and Sunday, that are combined onto one page), with the idea being that you have a new puzzle every day while also having a functioning calendar. + +The problem, in practice, is that it's a great pad of puzzles but not a great calendar because it turns out some days are harder than others and we just don't get through them at the necessary rate of one a day. Then, we may have a week's worth that gets batched on a lazy Sunday. + +Since I've already given you a [calendar][1] as a part of this series, I figure it's only fair to give you a Sudoku puzzle as well, except our command-line versions are decoupled so there's no pressure to complete exactly one a day. + +I found **nudoku** in my default repositories on Fedora, so installing it was as simple as: + +``` +$ sudo dnf install nudoku +``` + +Once installed, just invoke **nudoku** by name to launch it, and it should be fairly self-explanatory from there. If you've never played Sudoku before, it's fairly simple: You need to make sure that each row, each column, and each of the nine 3x3 squares that make up the large square each have one of every digit, 1-9. + +You can find **nudoku** 's c source code [on GitHub][2] under a GPLv3 license. +![](https://opensource.com/sites/default/files/uploads/linux-toy-nudoku-animated.gif) +Do you have a favorite command-line toy that you we should have included? Our calendar is basically set for the remainder of the series, but we'd still love to feature some cool command-line toys in the new year. Let me know in the comments below, and I'll check it out. And let me know what you thought of today's amusement. + +Be sure to check out yesterday's toy, [Use your Linux terminal to celebrate a banner][3] [year][3], and come back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-nudoku + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/18/12/linux-toy-cal +[2]: https://github.com/jubalh/nudoku +[3]: https://opensource.com/article/18/12/linux-toy-figlet diff --git a/sources/tech/20181220 Getting started with Prometheus.md b/sources/tech/20181220 Getting started with Prometheus.md new file mode 100644 index 0000000000..79704addb7 --- /dev/null +++ b/sources/tech/20181220 Getting started with Prometheus.md @@ -0,0 +1,166 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Getting started with Prometheus) +[#]: via: (https://opensource.com/article/18/12/introduction-prometheus) +[#]: author: (Michael Zamot https://opensource.com/users/mzamot) + +Getting started with Prometheus +====== +Learn to install and write queries for the Prometheus monitoring and alerting system. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/tools_sysadmin_cloud.png?itok=sUciG0Cn) + +[Prometheus][1] is an open source monitoring and alerting system that directly scrapes metrics from agents running on the target hosts and stores the collected samples centrally on its server. Metrics can also be pushed using plugins like **collectd_exporter** —although this is not Promethius' default behavior, it may be useful in some environments where hosts are behind a firewall or prohibited from opening ports by security policy. + +Prometheus, a project of the [Cloud Native Computing Foundation][2], scales up using a federation model, which enables one Prometheus server to scrape another Prometheus server. This allows creation of a hierarchical topology, where a central system or higher-level Prometheus server can scrape aggregated data already collected from subordinate instances. + +Besides the Prometheus server, its most common components are its [Alertmanager][3] and its exporters. + +Alerting rules can be created within Prometheus and configured to send custom alerts to Alertmanager. Alertmanager then processes and handles these alerts, including sending notifications through different mechanisms like email or third-party services like [PagerDuty][4]. + +Prometheus' exporters can be libraries, processes, devices, or anything else that exposes the metrics that will be scraped by Prometheus. The metrics are available at the endpoint **/metrics** , which allows Prometheus to scrape them directly without needing an agent. The tutorial in this article uses **node_exporter** to expose the target hosts' hardware and operating system metrics. Exporters' outputs are plaintext and highly readable, which is one of Prometheus' strengths. + +In addition, you can configure [Grafana][5] to use Prometheus as a backend to provide data visualization and dashboarding functions. + +### Making sense of Prometheus' configuration file + +The number of seconds between when **/metrics** is scraped controls the granularity of the time-series database. This is defined in the configuration file as the **scrape_interval** parameter, which by default is set to 60 seconds. + +Targets are set for each scrape job in the **scrape_configs** section. Each job has its own name and a set of labels that can help filter, categorize, and make it easier to identify the target. One job can have many targets. + +### Installing Prometheus + +In this tutorial, for simplicity, we will install a Prometheus server and **node_exporter** with docker. Docker should already be installed and configured properly on your system. For a more in-depth, automated method, I recommend Steve Ovens' article [How to use Ansible to set up system monitoring with Prometheus][6]. + +Before starting, create the Prometheus configuration file **prometheus.yml** in your work directory as follows: + +``` +global: +  scrape_interval:      15s +  evaluation_interval: 15s + +scrape_configs: +  - job_name: 'prometheus' + +        static_configs: +        - targets: ['localhost:9090'] + +  - job_name: 'webservers' + +        static_configs: +        - targets: [':9100'] +``` + +Start Prometheus with Docker by running the following command: + +``` +$ sudo docker run -d -p 9090:9090 -v +/path/to/prometheus.yml:/etc/prometheus/prometheus.yml +prom/prometheus +``` + +By default, the Prometheus server will use port 9090. If this port is already in use, you can change it by adding the parameter **\--web.listen-address=" :"** at the end of the previous command. + +In the machine you want to monitor, download and run the **node_exporter** container by using the following command: + +``` +$ sudo docker run -d -v "/proc:/host/proc" -v "/sys:/host/sys" -v +"/:/rootfs" --net="host" prom/node-exporter --path.procfs +/host/proc --path.sysfs /host/sys --collector.filesystem.ignored- +mount-points "^/(sys|proc|dev|host|etc)($|/)" +``` + +For the purposes of this learning exercise, you can install **node_exporter** and Prometheus on the same machine. Please note that it's not wise to run **node_exporter** under Docker in production—this is for testing purposes only. + +To verify that **node_exporter** is running, open your browser and navigate to **http:// :9100/metrics**. All the metrics collected will be displayed; these are the same metrics Prometheus will scrape. + +![](https://opensource.com/sites/default/files/uploads/check-node_exporter.png) + +To verify the Prometheus server installation, open your browser and navigate to . + +You should see the Prometheus interface. Click on **Status** and then **Targets**. Under State, you should see your machines listed as **UP**. + +![](https://opensource.com/sites/default/files/uploads/targets-up.png) + +### Using Prometheus queries + +It's time to get familiar with [PromQL][7], Prometheus' query syntax, and its graphing web interface. Go to **** on your Prometheus server. You will see a query editor and two tabs: Graph and Console. + +Prometheus stores all data as time series, identifying each one with a metric name. For example, the metric **node_filesystem_avail_bytes** shows the available filesystem space. The metric's name can be used in the expression box to select all of the time series with this name and produce an instant vector. If desired, these time series can be filtered using selectors and labels—a set of key-value pairs—for example: + +``` +node_filesystem_avail_bytes{fstype="ext4"} +``` + +When filtering, you can match "exactly equal" ( **=** ), "not equal" ( **!=** ), "regex-match" ( **=~** ), and "do not regex-match" ( **!~** ). The following examples illustrate this: + +To filter **node_filesystem_avail_bytes** to show both ext4 and XFS filesystems: + +``` +node_filesystem_avail_bytes{fstype=~"ext4|xfs"} +``` + +To exclude a match: + +``` +node_filesystem_avail_bytes{fstype!="xfs"} +``` + +You can also get a range of samples back from the current time by using square brackets. You can use **s** to represent seconds, **m** for minutes, **h** for hours, **d** for days, **w** for weeks, and **y** for years. When using time ranges, the vector returned will be a range vector. + +For example, the following command produces the samples from five minutes to the present: + +``` +node_memory_MemAvailable_bytes[5m] +``` + +Prometheus also includes functions to allow advanced queries, such as this: + +``` +100 core.md Dict.md lctt2014.md lctt2016.md lctt2018.md LICENSE published README.md scripts sources translated (1 - avg by(instance)(irate(node_cpu_seconds_total{job='webservers',mode='idle'}[5m]))) +``` + +Notice how the labels are used to filter the job and the mode. The metric **node_cpu_seconds_total** returns a counter, and the **irate()** function calculates the per-second rate of change based on the last two data points of the range interval (meaning the range can be smaller than five minutes). To calculate the overall CPU usage, you can use the idle mode of the **node_cpu_seconds_total** metric. The idle percent of a processor is the opposite of a busy processor, so the **irate** value is subtracted from 1. To make it a percentage, multiply it by 100. + +![](https://opensource.com/sites/default/files/uploads/cpu-usage.png) + +### Learn more + +Prometheus is a powerful, scalable, lightweight, and easy to use and deploy monitoring tool that is indispensable for every system administrator and developer. For these and other reasons, many companies are implementing Prometheus as part of their infrastructure. + +To learn more about Prometheus and its functions, I recommend the following resources: + ++ About [PromQL][8] ++ What [node_exporters collects][9] ++ [Prometheus functions][10] ++ [4 open source monitoring tools][11] ++ [Now available: The open source guide to DevOps monitoring tools][12] + + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/introduction-prometheus + +作者：[Michael Zamot][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/mzamot +[b]: https://github.com/lujun9972 +[1]: https://prometheus.io/ +[2]: https://www.cncf.io/ +[3]: https://prometheus.io/docs/alerting/alertmanager/ +[4]: https://en.wikipedia.org/wiki/PagerDuty +[5]: https://grafana.com/ +[6]: https://opensource.com/article/18/3/how-use-ansible-set-system-monitoring-prometheus +[7]: https://prometheus.io/docs/prometheus/latest/querying/basics/ +[8]: https://prometheus.io/docs/prometheus/latest/querying/basics/ +[9]: https://github.com/prometheus/node_exporter#collectors +[10]: https://prometheus.io/docs/prometheus/latest/querying/functions/ +[11]: https://opensource.com/article/18/8/open-source-monitoring-tools +[12]: https://opensource.com/article/18/8/now-available-open-source-guide-devops-monitoring-tools diff --git a/sources/tech/20181220 How To Install Microsoft .NET Core SDK On Linux.md b/sources/tech/20181220 How To Install Microsoft .NET Core SDK On Linux.md new file mode 100644 index 0000000000..728db3b7be --- /dev/null +++ b/sources/tech/20181220 How To Install Microsoft .NET Core SDK On Linux.md @@ -0,0 +1,337 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (How To Install Microsoft .NET Core SDK On Linux) +[#]: via: (https://www.ostechnix.com/how-to-install-microsoft-net-core-sdk-on-linux/) +[#]: author: (SK https://www.ostechnix.com/author/sk/) + +How To Install Microsoft .NET Core SDK On Linux +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/NET-Core-SDK-720x340.png) + +The **.NET Core** is a free, cross platform and open source framework developed by Microsoft to build desktop applications, mobile apps, web apps, IoT apps and gaming apps etc. If you’re dotnet developer coming from Windows platform, .NET core helps you to setup your development environment easily on any Linux and Unix-like operating systems. This step by step guide explains how to install Microsoft .NET Core SDK on Linux and how to write your first app using .Net. + +### Install Microsoft .NET Core SDK On Linux + +The .NET core supports GNU/Linux, Mac OS and Windows. .Net core can be installed on popular GNU/Linux operating systems including Debian, Fedora, CentOS, Oracle Linux, RHEL, SUSE/openSUSE, and Ubuntu. As of writing this guide, the latest .NET core version was **2.2**. + +On **Debian 9** , you can install .NET Core SDK as shown below. + +First of all, you need to register Microsoft key and add .NET repository by running the following commands: + +``` +$ wget -qO- https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > microsoft.asc.gpg +$ sudo mv microsoft.asc.gpg /etc/apt/trusted.gpg.d/ +$ wget -q https://packages.microsoft.com/config/debian/9/prod.list +$ sudo mv prod.list /etc/apt/sources.list.d/microsoft-prod.list +$ sudo chown root:root /etc/apt/trusted.gpg.d/microsoft.asc.gpg +$ sudo chown root:root /etc/apt/sources.list.d/microsoft-prod.list +``` + +After registering the key and adding the repository, install .NET SDK using commands: + +``` +$ sudo apt-get update +$ sudo apt-get install dotnet-sdk-2.2 +``` + +**On Debian 8:** + +Add Microsoft key and enable .NET repository: + +``` +$ wget -qO- https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > microsoft.asc.gpg +$ sudo mv microsoft.asc.gpg /etc/apt/trusted.gpg.d/ +$ wget -q https://packages.microsoft.com/config/debian/8/prod.list +$ sudo mv prod.list /etc/apt/sources.list.d/microsoft-prod.list +$ sudo chown root:root /etc/apt/trusted.gpg.d/microsoft.asc.gpg +$ sudo chown root:root /etc/apt/sources.list.d/microsoft-prod.list +``` + +Install .NET SDK: + +``` +$ sudo apt-get update +$ sudo apt-get install dotnet-sdk-2.2 +``` + +**On Fedora 28:** + +Add Microsoft key and enable .NET repository: + +``` +$ sudo rpm --import https://packages.microsoft.com/keys/microsoft.asc +$ wget -q https://packages.microsoft.com/config/fedora/27/prod.repo +$ sudo mv prod.repo /etc/yum.repos.d/microsoft-prod.repo +$ sudo chown root:root /etc/yum.repos.d/microsoft-prod.repo +``` + +Now, Install .NET SDK: + +``` +$ sudo dnf update +$ sudo dnf install dotnet-sdk-2.2 +``` + +On **Fedora 27** , add the key and repository using commands: + +``` +$ sudo rpm --import https://packages.microsoft.com/keys/microsoft.asc +$ wget -q https://packages.microsoft.com/config/fedora/27/prod.repo +$ sudo mv prod.repo /etc/yum.repos.d/microsoft-prod.repo +$ sudo chown root:root /etc/yum.repos.d/microsoft-prod.repo +``` + +And install .NET SDK using commands: + +``` +$ sudo dnf update +$ sudo dnf install dotnet-sdk-2.2 +``` + +**On CentOS/Oracle Linux:** + +Add Microsoft key and enable .NET core repository: + +``` +$ sudo rpm -Uvh https://packages.microsoft.com/config/rhel/7/packages-microsoft-prod.rpm +``` + +Update the repositories and install .NET SDK: + +``` +$ sudo yum update +$ sudo yum install dotnet-sdk-2.2 +``` + +**On openSUSE Leap:** + +Add key, enable repository and install necessary dependencies using the following commands: + +``` +$ sudo zypper install libicu +$ sudo rpm --import https://packages.microsoft.com/keys/microsoft.asc +$ wget -q https://packages.microsoft.com/config/opensuse/42.2/prod.repo +$ sudo mv prod.repo /etc/zypp/repos.d/microsoft-prod.repo +$ sudo chown root:root /etc/zypp/repos.d/microsoft-prod.repo +``` + +Update the repositories and Install .NET SDK using commands: + +``` +$ sudo zypper update +$ sudo zypper install dotnet-sdk-2.2 +``` + +**On Ubuntu 18.04 LTS:** + +Register the Microsoft key and .NET core repository using commands: + +``` +$ wget -q https://packages.microsoft.com/config/ubuntu/18.04/packages-microsoft-prod.deb +$ sudo dpkg -i packages-microsoft-prod.deb +``` + +Enable ‘Universe’ repository using: + +``` +$ sudo add-apt-repository universe +``` + +Then, install .NET Core SDK using command: + +``` +$ sudo apt-get install apt-transport-https +$sudo apt-get update +$ sudo apt-get install dotnet-sdk-2.2 +``` + +**On Ubuntu 16.04 LTS:** + +Register Microsoft key and .NET repository using commands: + +``` +$ wget -q https://packages.microsoft.com/config/ubuntu/16.04/packages-microsoft-prod.deb +$ sudo dpkg -i packages-microsoft-prod.deb +``` + +And then, Install .NET core SDK: + +``` +$ sudo apt-get install apt-transport-https +$ sudo apt-get update +$ sudo apt-get install dotnet-sdk-2.2 +``` + +### Create Your First App + +We have successfully installed .Net Core SDK in our Linux box. It is time to create our first app using dotnet. + +For the purpose of this guide, I am going to create a new app called **“ostechnixApp”**. To do so, simply run the following command: + +``` +$ dotnet new console -o ostechnixApp +``` + +**Sample output:** + +``` +Welcome to .NET Core! +--------------------- +Learn more about .NET Core: https://aka.ms/dotnet-docs +Use 'dotnet --help' to see available commands or visit: https://aka.ms/dotnet-cli-docs + +Telemetry +--------- +The .NET Core tools collect usage data in order to help us improve your experience. The data is anonymous and doesn't include command-line arguments. The data is collected by Microsoft and shared with the community. You can opt-out of telemetry by setting the DOTNET_CLI_TELEMETRY_OPTOUT environment variable to '1' or 'true' using your favorite shell. + +Read more about .NET Core CLI Tools telemetry: https://aka.ms/dotnet-cli-telemetry + +ASP.NET Core +------------ +Successfully installed the ASP.NET Core HTTPS Development Certificate. +To trust the certificate run 'dotnet dev-certs https --trust' (Windows and macOS only). For establishing trust on other platforms refer to the platform specific documentation. +For more information on configuring HTTPS see https://go.microsoft.com/fwlink/?linkid=848054. +Getting ready... +The template "Console Application" was created successfully. + +Processing post-creation actions... +Running 'dotnet restore' on ostechnixApp/ostechnixApp.csproj... +Restoring packages for /home/sk/ostechnixApp/ostechnixApp.csproj... +Generating MSBuild file /home/sk/ostechnixApp/obj/ostechnixApp.csproj.nuget.g.props. +Generating MSBuild file /home/sk/ostechnixApp/obj/ostechnixApp.csproj.nuget.g.targets. +Restore completed in 894.27 ms for /home/sk/ostechnixApp/ostechnixApp.csproj. + +Restore succeeded. +``` + +As you can see in the above output, .Net has created a new application of type console. The parameter -o creates a directory named “ostechnixApp” where you store your app data with all necessary files. + +Let us switch to ostechnixApp directory and see what’s in there. + +``` +$ cd ostechnixApp/ +$ ls +obj ostechnixApp.csproj Program.cs +``` + +As you there are three files named **ostechnixApp.csproj** and **Program.cs** and one directory named **obj**. By default, the Program.cs file will contain the code to run the ‘Hello World’ program in the console. Let us have a look at the code. + +``` +$ cat Program.cs +using System; + +namespace ostechnixApp +{ + class Program + { + static void Main(string[] args) + { + Console.WriteLine("Hello World!"); + } + } +} +``` + +To run the newly created app, simply run the following command: + +``` +$ dotnet run +Hello World! +``` + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/run-dotnet.png) + +Simple, isn’t it? Yes, it is! Now, you can write your code in the **Program.cs** file and run it as shown above. + +Alternatively, you can create a new directory, for example mycode, using commands: + +``` +$ mkdir ~/.mycode + +$ cd mycode/ +``` + +…and make that as your new development environment by running the following command: + +``` +$ dotnet new console +``` + +Sample output: + +``` +The template "Console Application" was created successfully. + +Processing post-creation actions... +Running 'dotnet restore' on /home/sk/mycode/mycode.csproj... +Restoring packages for /home/sk/mycode/mycode.csproj... +Generating MSBuild file /home/sk/mycode/obj/mycode.csproj.nuget.g.props. +Generating MSBuild file /home/sk/mycode/obj/mycode.csproj.nuget.g.targets. +Restore completed in 331.87 ms for /home/sk/mycode/mycode.csproj. + +Restore succeeded. +``` + +The above command will create two files named **mycode.csproj** and **Program.cs** and one directory named **obj**. Open the Program.cs file in your favorite editor, delete or modify the existing ‘hello world’ code with your own code. + +Once the code is written, save and close the Program.cs file and run the app using command: + +``` +$ dotnet run +``` + +To check the installed .NET core SDK version, simply run: + +``` +$ dotnet --version +2.2.101 +``` + +To get help, run: + +``` +$ dotnet --help +``` + +### Get Microsoft Visual Studio Code Editor + +To write the code, you can use your favorite editors of your choice. Microsoft has also its own editor named “ **Microsoft Visual Studio Code** ” with support for .NET. It is an open source, lightweight and powerful source code editor. It comes with built-in support for JavaScript, TypeScript and Node.js and has a rich ecosystem of extensions for other languages (such as C++, C#, Python, PHP, Go) and runtimes (such as .NET and Unity). It is a cross-platform code editor, so you can use it in Microsoft Windows, GNU/Linux, and Mac OS X. You can use it if you’re interested. + +To know how to install and use it on Linux, please refer the following guide. + +[Install Microsoft Visual Studio Code In Linux][3] + +[**This page**][1] has some basic tutorials to learn .NET Core and .NET Core SDK tools using Visual Studio Code editor. Go and check them to learn more. + +### Telemetry + +By default, the .NET core SDK will collect the usage data using a feature called **‘Telemetry’**. The collected data is anonymous and shared to the development team and community under the [Creative Commons Attribution License][2]. So the .NET team will understand how the tools are used and decide how they can be improved over time. If you don’t want to share your usage information, you can simply opt-out of telemetry by setting the **DOTNET_CLI_TELEMETRY_OPTOUT** environment variable to **‘1’** or **‘true’** using your favorite shell. + +And, that’s all. You know how to install .NET Core SDK on various Linux platforms and how to create a basic app using it. TO learn more about .NET usage, refer the links given at the end of this guide. + +More good stuffs to come. Stay tuned! + +Cheers! + + + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/how-to-install-microsoft-net-core-sdk-on-linux/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: https://docs.microsoft.com/en-us/dotnet/core/tutorials/index +[2]: https://creativecommons.org/licenses/by/4.0/ +[3]: https://www.ostechnix.com/install-microsoft-visual-studio-code-linux/ diff --git a/sources/tech/20181220 Let your Linux terminal speak its mind.md b/sources/tech/20181220 Let your Linux terminal speak its mind.md new file mode 100644 index 0000000000..7f237c0962 --- /dev/null +++ b/sources/tech/20181220 Let your Linux terminal speak its mind.md @@ -0,0 +1,62 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Let your Linux terminal speak its mind) +[#]: via: (https://opensource.com/article/18/12/linux-toy-espeak) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Let your Linux terminal speak its mind +====== +eSpeak is an open source text-to-speech synthesizer that can be invoked from the Linux command line. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-cava.png?itok=4EWYL8uZ) + +Greetings from another day in our 24-day-long Linux command-line toys advent calendar. If this is your first visit to the series, you might be asking yourself what a command-line toy even is. We’re figuring that out as we go, but generally, it could be a game, or any simple diversion that helps you have fun at the terminal. + +We hope that even if you've seen some of these before, there will be something new for everybody in our series. + +Some of you may be too young to remember, but before there was Alexa, Siri, or the Google Assistant, computers still had voices. + +Many of us will never forget HAL 9000 from [2001: A Space Odessey][1] helpfully conversing with the crew (sorry, Dave). But between 1960s science fiction and today, there was a whole generation of speaking computers. Some of them great, most of them, not so great. + +One of my favorites is the open source project [eSpeak][2]. It's available in many forms, including a library version you can use to include speech technology in your own project, but it also coms as a command-line program that you can install and use easily. In my distribution, this was as simple as: + +``` +$ sudo dnf install espeak +``` + +Invoking eSpeak then can be invoked either interactively, or by piping text to it using the output of another program or a simple echo command. There are a number of [voice files][3] available for eSpeak, and if you're especially bored over the holidays, you could even create your own. + +A fork of eSpeak called eSpeak NG ("Next Generation") was created in 2015 from some developers who wanted to continue development of the otherwise lightly-updated eSpeak. eSpeak is made available as open source under a GPL version 3 license, and you can find out more about the project and download the source code [on SourceForge][2]. + +I'll also throw in a bonus toy today, [cava][4]. Because I've been eager to give each of these articles a unique screenshot as the lead image, and today's toy outputs sound rather than something visual, I needed to find something to fill the space. Short for "console-based audio visualizer for ALSA" (although it supports more than just ALSA now), cava is a nice MIT-licensed terminal audio visualization tool that's fun to watch. Below, is a visualization of eSpeak's output of the following: + +``` +$ echo "Rudolph, the red-nosed reindeer, had a very shiny nose." | espeak +``` + +![](https://opensource.com/sites/default/files/uploads/linux-toy-cava.gif) + +Do you have a favorite command-line toy that you we should have included? Our calendar is basically set for the remainder of the series, but we'd still love to feature some cool command-line toys in the new year. Let me know in the comments below, and I'll check it out. And let me know what you thought of today's amusement. + +Be sure to check out yesterday's toy, [Solve a puzzle at the Linux command line with nudoku][5], and come back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-espeak + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://en.wikipedia.org/wiki/2001:_A_Space_Odyssey_(film) +[2]: http://espeak.sourceforge.net/ +[3]: http://espeak.sourceforge.net/voices.html +[4]: https://github.com/karlstav/cava +[5]: https://opensource.com/article/18/12/linux-toy-nudoku diff --git a/sources/tech/20181221 An Easy Way To Remove Programs Installed From Source In Linux.md b/sources/tech/20181221 An Easy Way To Remove Programs Installed From Source In Linux.md new file mode 100644 index 0000000000..7e3378b4e3 --- /dev/null +++ b/sources/tech/20181221 An Easy Way To Remove Programs Installed From Source In Linux.md @@ -0,0 +1,200 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (An Easy Way To Remove Programs Installed From Source In Linux) +[#]: via: (https://www.ostechnix.com/an-easy-way-to-remove-programs-installed-from-source-in-linux/) +[#]: author: (SK https://www.ostechnix.com/author/sk/) + +An Easy Way To Remove Programs Installed From Source In Linux +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/stow-1-720x340.jpg) + +Not all programs available in the official or third-party repositories, so you can’t install them using the regular package managers. Some times, you have to install the programs by manually compiling from source. As you may already know, when you install programs from source, the package files will be copied to multiple locations, such as **/usr/local/bin** , **/usr/local/etc/** , on the filesystem. If the installed program from source doesn’t have a built-in uninstaller, it is going to be a tedious task to remove the packages when you don’t need it anymore. You may need to spend couple (or several) minutes to find those package files and remove them manually. This is what I have been doing up until I stumbled upon a utility named **“GNU Stow”**. Thankfully, Stow has a fantastic way to easily manage programs installed from source. + +To quote the official website, + +> **GNU Stow is a symlink farm manager which takes distinct packages of software and/or data located in separate directories on the filesystem, and makes them appear to be installed in the same place.** + +To put this simply, Stow helps you to keep the package files organized in a way to easily manageable. In this method, the files will not be copied to multiple locations. Instead, all files are saved in a specific folder, usually under the program name itself, and Stow creates symbolic links to all the programs’ files into the appropriate places. For example, **/usr/local/bin** could contain symlinks to files within **/usr/local/stow/vim/bin** , **/usr/local/stow/python/bin** etc., and likewise recursively for any other subdirectories such as **…/share** , **…/man** , and so on. In this tutorial, I will show you how to easily manage programs installed from source using Stow with a practical example. Read on. + +### Installing GNU Stow + +GNU Stow is available in the default repositories of popular Linux operating systems. + +On **Arch Linux** and its variants, run the following command to install Stow. + +``` +$ sudo pacman -S stow +``` + +On **Debian** , **Ubuntu** , **Linux Mint** : + +``` +$ sudo apt install stow +``` + +On **Fedora** : + +``` +$ sudo dnf install stow +``` + +On **RHEL/CentOS** : + +``` +$ sudo yum install epel-release + +$ sudo yum install stow +``` + +### Easily Remove Programs Installed From Source In Linux + +As I already mentioned earlier, all program files of a package will be saved in a root folder located in **/usr/local/stow/**. Under this root or parent directory, each package will be saved in its own private sub-directory. For example, if we install Vim editor from source, all program files and directories related to Vim will be saved under **/usr/local/stow/vim** folder. If you install python from source, all files related to python will be kept under **/usr/local/stow/python** and so on. + +Let me install a program, for example **hello** , from source. + +First download the ‘hello’ program’s tarball. + +``` +$ wget http://ftp.gnu.org/gnu/hello/hello-2.10.tar.gz +``` + +Extract the downloaded tarball using command: + +``` +$ tar -zxvf hello-2.10.tar.gz +``` + +The above command will create a directory named ‘hello-2.10’ in the current working directory and extract all contents in it. + +Switch to the extracted directory: + +``` +$ cd hello-2.10/ +``` + +Run the following command with –prefix option. + +``` +$ ./configure --prefix=/usr/local/stow/hello +``` + +The above command will save the build files in the specified location i.e **/usr/local/stow/hello** in our case. + +Finally, build and install the hello program using the following commands: + +``` +$ make + +$ sudo make install +``` + +That’s it. The hello program has been installed in **/usr/local/stow/hello/** location. You can verify it with ‘ls’ command as shown below. + +``` +$ ls /usr/local/stow/hello/ +bin share +``` + +Finally, go to the **/usr/local/stow/** directory and run the following command to generate the necessary symlinks. + +``` +$ cd /usr/local/stow/ + +$ sudo stow hello +``` + +All done! + +What just happened is all the files and directories contained in the hello package have been symlinked to the directory **/usr/local/**. In other words, **/usr/local/stow/hello/bin** has been symlinked to **/usr/local/bin** and **/usr/local/stow/hello/share** has been symlinked to **/usr/local/share** and **/usr/local/stow/hello/share/man** has been symlinked to **/usr/local/share/man** and so on. + +You can verify them using ‘ls’ command: + +``` +$ ls /usr/local/bin/ +hello +``` + +Let us check if the hello program is working or not using command: + +``` +$ hello +Hello, world! +``` + +Yeah, it is working!! + +Similarly, you can install programs as described above under its own sub-directory. + +Here is the contents of the Stow root directory: + +``` +$ tree /usr/local/stow/ +``` + +![][2] + +See? The hello program is installed /usr/local/stow/hello/ location. Like wise, all packages will be kept under their own directory. + +Here comes the main part. Let us remove the hello program. To do so, go to **/usr/local/stow/** directory: + +``` +$ cd /usr/local/stow/ +``` + +..and run the following command: + +``` +$ sudo stow --delete hello +``` + +The hello program has just been removed. You can verify if it is really removed using command: + +``` +$ hello +-bash: /usr/local/bin/hello: No such file or directory +``` + +![][3] + +See? Hello program is removed! + +Please note that Stow has removed the symlinks only. All program files and directories related to hello program are still available in **/usr/local/stow/hello** folder. So, you can install the hello program again without having to download the actual source file. If you don’t want it anymore, simply delete the folder. + +``` +$ sudo rm -fr /usr/local/stow/hello/ +``` + +To know more details about Stow, refer the man pages. + +``` +$ man stow +``` + + +Stow helps you to uninstall the programs as easily as you install them. If you are wondering how to effectively manage a lot of programs installed from source, GNU Stow is one such program to make this task a lot easier. Give it a try, you won’t be disappointed. + +And, that’s all for now. Hope this was useful. More good stuffs to come. Stay tuned! + +Cheers! + + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/an-easy-way-to-remove-programs-installed-from-source-in-linux/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[2]: http://www.ostechnix.com/wp-content/uploads/2018/12/tree-command.png +[3]: http://www.ostechnix.com/wp-content/uploads/2018/12/hello-world.png diff --git a/sources/tech/20181221 Large files with Git- LFS and git-annex.md b/sources/tech/20181221 Large files with Git- LFS and git-annex.md new file mode 100644 index 0000000000..29a76f810f --- /dev/null +++ b/sources/tech/20181221 Large files with Git- LFS and git-annex.md @@ -0,0 +1,145 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Large files with Git: LFS and git-annex) +[#]: via: (https://anarc.at/blog/2018-12-21-large-files-with-git/) +[#]: author: (Anarc.at https://anarc.at/) + +Large files with Git: LFS and git-annex +====== + +Git does not handle large files very well. While there is work underway to handle large repositories through the [commit graph work][2], Git's internal design has remained surprisingly constant throughout its history, which means that storing large files into Git comes with a significant and, ultimately, prohibitive performance cost. Thankfully, other projects are helping Git address this challenge. This article compares how Git LFS and git-annex address this problem and should help readers pick the right solution for their needs. + +### The problem with large files + +As readers probably know, Linus Torvalds wrote Git to manage the history of the kernel source code, which is a large collection of small files. Every file is a "blob" in Git's object store, addressed by its cryptographic hash. A new version of that file will store a new blob in Git's history, with no deduplication between the two versions. The pack file format can store binary deltas between similar objects, but if many objects of similar size change in a repository, that algorithm might fail to properly deduplicate. In practice, large binary files (say JPEG images) have an irritating tendency of changing completely when even the smallest change is made, which makes delta compression useless. + +There have been different attempts at fixing this in the past. In 2006, Torvalds worked on [improving the pack-file format][3] to reduce object duplication between the index and the pack files. Those changes were eventually reverted because, as Nicolas Pitre [put it][4]: "that extra loose object format doesn't appear to be worth it anymore". + +Then in 2009, [Caca Labs][5] worked on improving the `fast-import` and `pack-objects` Git commands to do special handling for big files, in an effort called [git-bigfiles][6]. Some of those changes eventually made it into Git: for example, since [1.7.6][7], Git will stream large files directly to a pack file instead of holding them all in memory. But files are still kept forever in the history. + +An example of trouble I had to deal with is for the Debian security tracker, which follows all security issues in the entire Debian history in a single file. That file is around 360,000 lines for a whopping 18MB. The resulting repository takes 1.6GB of disk space and a local clone takes 21 minutes to perform, mostly taken up by Git resolving deltas. Commit, push, and pull are noticeably slower than a regular repository, taking anywhere from a few seconds to a minute depending one how old the local copy is. And running annotate on that large file can take up to ten minutes. So even though that is a simple text file, it's grown large enough to cause significant problems for Git, which is otherwise known for stellar performance. + +Intuitively, the problem is that Git needs to copy files into its object store to track them. Third-party projects therefore typically solve the large-files problem by taking files out of Git. In 2009, Git evangelist Scott Chacon released [GitMedia][8], which is a Git filter that simply takes large files out of Git. Unfortunately, there hasn't been an official release since then and it's [unclear][9] if the project is still maintained. The next effort to come up was [git-fat][10], first released in 2012 and still maintained. But neither tool has seen massive adoption yet. If I would have to venture a guess, it might be because both require manual configuration. Both also require a custom server (rsync for git-fat; S3, SCP, Atmos, or WebDAV for GitMedia) which limits collaboration since users need access to another service. + +### Git LFS + +That was before GitHub [released][11] Git Large File Storage (LFS) in August 2015. Like all software taking files out of Git, LFS tracks file hashes instead of file contents. So instead of adding large files into Git directly, LFS adds a pointer file to the Git repository, which looks like this: + +``` +version https://git-lfs.github.com/spec/v1 +oid sha256:4d7a214614ab2935c943f9e0ff69d22eadbb8f32b1258daaa5e2ca24d17e2393 +size 12345 +``` + +LFS then uses Git's smudge and clean filters to show the real file on checkout. Git only stores that small text file and does so efficiently. The downside, of course, is that large files are not version controlled: only the latest version of a file is kept in the repository. + +Git LFS can be used in any repository by installing the right hooks with `git lfs install` then asking LFS to track any given file with `git lfs track`. This will add the file to the `.gitattributes` file which will make Git run the proper LFS filters. It's also possible to add patterns to the `.gitattributes` file, of course. For example, this will make sure Git LFS will track MP3 and ZIP files: + +``` +$ cat .gitattributes +*.mp3 filter=lfs -text +*.zip filter=lfs -text +``` + +After this configuration, we use Git normally: `git add`, `git commit`, and so on will talk to Git LFS transparently. + +The actual files tracked by LFS are copied to a path like `.git/lfs/objects/{OID-PATH}`, where `{OID-PATH}` is a sharded file path of the form `OID[0:2]/OID[2:4]/OID` and where `OID` is the content's hash (currently SHA-256) of the file. This brings the extra feature that multiple copies of the same file in the same repository are automatically deduplicated, although in practice this rarely occurs. + +Git LFS will copy large files to that internal storage on `git add`. When a file is modified in the repository, Git notices, the new version is copied to the internal storage, and the pointer file is updated. The old version is left dangling until the repository is pruned. + +This process only works for new files you are importing into Git, however. If a Git repository already has large files in its history, LFS can fortunately "fix" repositories by retroactively rewriting history with [git lfs migrate][12]. This has all the normal downsides of rewriting history, however --- existing clones will have to be reset to benefit from the cleanup. + +LFS also supports [file locking][13], which allows users to claim a lock on a file, making it read-only everywhere except in the locking repository. This allows users to signal others that they are working on an LFS file. Those locks are purely advisory, however, as users can remove other user's locks by using the `--force` flag. LFS can also [prune][14] old or unreferenced files. + +The main [limitation][15] of LFS is that it's bound to a single upstream: large files are usually stored in the same location as the central Git repository. If it is hosted on GitHub, this means a default quota of 1GB storage and bandwidth, but you can purchase additional "packs" to expand both of those quotas. GitHub also limits the size of individual files to 2GB. This [upset][16] some users surprised by the bandwidth fees, which were previously hidden in GitHub's cost structure. + +While the actual server-side implementation used by GitHub is closed source, there is a [test server][17] provided as an example implementation. Other Git hosting platforms have also [implemented][18] support for the LFS [API][19], including GitLab, Gitea, and BitBucket; that level of adoption is something that git-fat and GitMedia never achieved. LFS does support hosting large files on a server other than the central one --- a project could run its own LFS server, for example --- but this will involve a different set of credentials, bringing back the difficult user onboarding that affected git-fat and GitMedia. + +Another limitation is that LFS only supports pushing and pulling files over HTTP(S) --- no SSH transfers. LFS uses some [tricks][20] to bypass HTTP basic authentication, fortunately. This also might change in the future as there are proposals to add [SSH support][21], resumable uploads through the [tus.io protocol][22], and other [custom transfer protocols][23]. + +Finally, LFS can be slow. Every file added to LFS takes up double the space on the local filesystem as it is copied to the `.git/lfs/objects` storage. The smudge/clean interface is also slow: it works as a pipe, but buffers the file contents in memory each time, which can be prohibitive with files larger than available memory. + +### git-annex + +The other main player in large file support for Git is git-annex. We [covered the project][24] back in 2010, shortly after its first release, but it's certainly worth discussing what has changed in the eight years since Joey Hess launched the project. + +Like Git LFS, git-annex takes large files out of Git's history. The way it handles this is by storing a symbolic link to the file in `.git/annex`. We should probably credit Hess for this innovation, since the Git LFS storage layout is obviously inspired by git-annex. The original design of git-annex introduced all sorts of problems however, especially on filesystems lacking symbolic-link support. So Hess has implemented different solutions to this problem. Originally, when git-annex detected such a "crippled" filesystem, it switched to [direct mode][25], which kept files directly in the work tree, while internally committing the symbolic links into the Git repository. This design turned out to be a little confusing to users, including myself; I have managed to shoot myself in the foot more than once using this system. + +Since then, git-annex has adopted a different v7 mode that is also based on smudge/clean filters, which it called "[unlocked files][26]". Like Git LFS, unlocked files will double disk space usage by default. However it is possible to reduce disk space usage by using "thin mode" which uses hard links between the internal git-annex disk storage and the work tree. The downside is, of course, that changes are immediately performed on files, which means previous file versions are automatically discarded. This can lead to data loss if users are not careful. + +Furthermore, git-annex in v7 mode suffers from some of the performance problems affecting Git LFS, because both use the smudge/clean filters. Hess actually has [ideas][27] on how the smudge/clean interface could be improved. He proposes changing Git so that it stops buffering entire files into memory, allows filters to access the work tree directly, and adds the hooks he found missing (for `stash`, `reset`, and `cherry-pick`). Git-annex already implements some tricks to work around those problems itself but it would be better for those to be implemented in Git natively. + +Being more distributed by design, git-annex does not have the same "locking" semantics as LFS. Locking a file in git-annex means protecting it from changes, so files need to actually be in the "unlocked" state to be editable, which might be counter-intuitive to new users. In general, git-annex has some of those unusual quirks and interfaces that often come with more powerful software. + +And git-annex is much more powerful: it not only addresses the "large-files problem" but goes much further. For example, it supports "partial checkouts" --- downloading only some of the large files. I find that especially useful to manage my video, music, and photo collections, as those are too large to fit on my mobile devices. Git-annex also has support for location tracking, where it knows how many copies of a file exist and where, which is useful for archival purposes. And while Git LFS is only starting to look at transfer protocols other than HTTP, git-annex already supports a [large number][28] through a [special remote protocol][29] that is fairly easy to implement. + +"Large files" is therefore only scratching the surface of what git-annex can do: I have used it to build an [archival system for remote native communities in northern Québec][30], while others have built a [similar system in Brazil][31]. It's also used by the scientific community in projects like [GIN][32] and [DataLad][33], which manage terabytes of data. Another example is the [Japanese American Legacy Project][34] which manages "upwards of 100 terabytes of collections, transporting them from small cultural heritage sites on USB drives". + +Unfortunately, git-annex is not well supported by hosting providers. GitLab [used to support it][35], but since it implemented Git LFS, it [dropped support for git-annex][36], saying it was a "burden to support". Fortunately, thanks to git-annex's flexibility, it may eventually be possible to treat [LFS servers as just another remote][37] which would make git-annex capable of storing files on those servers again. + +### Conclusion + +Git LFS and git-annex are both mature and well maintained programs that deal efficiently with large files in Git. LFS is easier to use and is well supported by major Git hosting providers, but it's less flexible than git-annex. + +Git-annex, in comparison, allows you to store your content anywhere and espouses Git's distributed nature more faithfully. It also uses all sorts of tricks to save disk space and improve performance, so it should generally be faster than Git LFS. Learning git-annex, however, feels like learning Git: you always feel you are not quite there and you can always learn more. It's a double-edged sword and can feel empowering for some users and terrifyingly hard for others. Where you stand on the "power-user" scale, along with project-specific requirements will ultimately determine which solution is the right one for you. + +Ironically, after thorough evaluation of large-file solutions for the Debian security tracker, I ended up proposing to rewrite history and [split the file by year][38] which improved all performance markers by at least an order of magnitude. As it turns out, keeping history is critical for the security team so any solution that moves large files outside of the Git repository is not acceptable to them. Therefore, before adding large files into Git, you might want to think about organizing your content correctly first. But if large files are unavoidable, the Git LFS and git-annex projects allow users to keep using most of their current workflow. + +> This article [first appeared][39] in the [Linux Weekly News][40]. + +-------------------------------------------------------------------------------- + +via: https://anarc.at/blog/2018-12-21-large-files-with-git/ + +作者：[Anarc.at][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://anarc.at/ +[b]: https://github.com/lujun9972 +[1]: https://anarc.at/blog/ +[2]: https://github.com/git/git/blob/master/Documentation/technical/commit-graph.txt +[3]: https://public-inbox.org/git/Pine.LNX.4.64.0607111010320.5623@g5.osdl.org/ +[4]: https://public-inbox.org/git/alpine.LFD.0.99.0705091422130.24220@xanadu.home/ +[5]: http://caca.zoy.org/ +[6]: http://caca.zoy.org/wiki/git-bigfiles +[7]: https://public-inbox.org/git/7v8vsnz2nc.fsf@alter.siamese.dyndns.org/ +[8]: https://github.com/alebedev/git-media +[9]: https://github.com/alebedev/git-media/issues/15 +[10]: https://github.com/jedbrown/git-fat +[11]: https://blog.github.com/2015-04-08-announcing-git-large-file-storage-lfs/ +[12]: https://github.com/git-lfs/git-lfs/blob/master/docs/man/git-lfs-migrate.1.ronn +[13]: https://github.com/git-lfs/git-lfs/wiki/File-Locking +[14]: https://github.com/git-lfs/git-lfs/blob/master/docs/man/git-lfs-prune.1.ronn +[15]: https://github.com/git-lfs/git-lfs/wiki/Limitations +[16]: https://medium.com/@megastep/github-s-large-file-storage-is-no-panacea-for-open-source-quite-the-opposite-12c0e16a9a91 +[17]: https://github.com/git-lfs/lfs-test-server +[18]: https://github.com/git-lfs/git-lfs/wiki/Implementations%0A +[19]: https://github.com/git-lfs/git-lfs/tree/master/docs/api +[20]: https://github.com/git-lfs/git-lfs/blob/master/docs/api/authentication.md +[21]: https://github.com/git-lfs/git-lfs/blob/master/docs/proposals/ssh_adapter.md +[22]: https://tus.io/ +[23]: https://github.com/git-lfs/git-lfs/blob/master/docs/custom-transfers.md +[24]: https://lwn.net/Articles/419241/ +[25]: http://git-annex.branchable.com/direct_mode/ +[26]: https://git-annex.branchable.com/tips/unlocked_files/ +[27]: http://git-annex.branchable.com/todo/git_smudge_clean_interface_suboptiomal/ +[28]: http://git-annex.branchable.com/special_remotes/ +[29]: http://git-annex.branchable.com/special_remotes/external/ +[30]: http://isuma-media-players.readthedocs.org/en/latest/index.html +[31]: https://github.com/RedeMocambos/baobaxia +[32]: https://web.gin.g-node.org/ +[33]: https://www.datalad.org/ +[34]: http://www.densho.org/ +[35]: https://docs.gitlab.com/ee/workflow/git_annex.html +[36]: https://gitlab.com/gitlab-org/gitlab-ee/issues/1648 +[37]: https://git-annex.branchable.com/todo/LFS_API_support/ +[38]: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=908678#52 +[39]: https://lwn.net/Articles/774125/ +[40]: http://lwn.net/ diff --git a/sources/tech/20181222 How to detect automatically generated emails.md b/sources/tech/20181222 How to detect automatically generated emails.md new file mode 100644 index 0000000000..2ccaeddeee --- /dev/null +++ b/sources/tech/20181222 How to detect automatically generated emails.md @@ -0,0 +1,144 @@ +[#]: collector: (lujun9972) +[#]: translator: (wyxplus) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (How to detect automatically generated emails) +[#]: via: (https://arp242.net/weblog/autoreply.html) +[#]: author: (Martin Tournoij https://arp242.net/) + +How to detect automatically generated emails +====== + +### How to detect automatically generated emails + + +When you send out an auto-reply from an email system you want to take care to not send replies to automatically generated emails. At best, you will get a useless delivery failure. At words, you will get an infinite email loop and a world of chaos. + +Turns out that reliably detecting automatically generated emails is not always easy. Here are my observations based on writing a detector for this and scanning about 100,000 emails with it (extensive personal archive and company archive). + +### Auto-submitted header + +Defined in [RFC 3834][1]. + +This is the ‘official’ standard way to indicate your message is an auto-reply. You should **not** send a reply if `Auto-Submitted` is present and has a value other than `no`. + +### X-Auto-Response-Suppress header + +Defined [by Microsoft][2] + +This header is used by Microsoft Exchange, Outlook, and perhaps some other products. Many newsletters and such also set this. You should **not** send a reply if `X-Auto-Response-Suppress` contains `DR` (“Suppress delivery reports”), `AutoReply` (“Suppress auto-reply messages other than OOF notifications”), or `All`. + +### List-Id and List-Unsubscribe headers + +Defined in [RFC 2919][3] + +You usually don’t want to send auto-replies to mailing lists or news letters. Pretty much all mail lists and most newsletters set at least one of these headers. You should **not** send a reply if either of these headers is present. The value is unimportant. + +### Feedback-ID header + +Defined [by Google][4]. + +Gmail uses this header to identify mail newsletters, and uses it to generate statistics/reports for owners of those newsletters. You should **not** send a reply if this headers is present; the value is unimportant. + +### Non-standard ways + +The above methods are well-defined and clear (even though some are non-standard). Unfortunately some email systems do not use any of them :-( Here are some additional measures. + +#### Precedence header + +Not really defined anywhere, mentioned in [RFC 2076][5] where its use is discouraged (but this header is commonly encountered). + +Note that checking for the existence of this field is not recommended, as some ails use `normal` and some other (obscure) values (this is not very common though). + +My recommendation is to **not** send a reply if the value case-insensitively matches `bulk`, `auto_reply`, or `list`. + +#### Other obscure headers + +A collection of other (somewhat obscure) headers I’ve encountered. I would recommend **not** sending an auto-reply if one of these is set. Most mails also set one of the above headers, but some don’t (but it’s not very common). + + * `X-MSFBL`; can’t really find a definition (Microsoft header?), but I only have auto-generated mails with this header. + + * `X-Loop`; not really defined anywhere, and somewhat rare, but sometimes it’s set. It’s most often set to the address that should not get emails, but `X-Loop: yes` is also encountered. + + * `X-Autoreply`; fairly rare, and always seems to have a value of `yes`. + + + + +#### Email address + +Check if the `From` or `Reply-To` headers contains `noreply`, `no-reply`, or `no_reply` (regex: `^no.?reply@`). + +#### HTML only + +If an email only has a HTML part, but no text part it’s a good indication this is an auto-generated mail or newsletter. Pretty much all mail clients also set a text part. + +#### Delivery failures + +Many delivery failure messages don’t really indicate that they’re failures. Some ways to check this: + + * `From` contains `mailer-daemon` or `Mail Delivery Subsystem` + + + +Many mail libraries leave some sort of footprint, and most regular mail clients override this with their own data. Checking for this seems to work fairly well. + + * `X-Mailer: Microsoft CDO for Windows 2000` – Set by some MS software; I can only find it on autogenerated mails. Yes, it’s still used in 2015. + + * `Message-ID` header contains `.JavaMail.` – I’ve found a few (5 on 50k) regular messages with this, but not many; the vast majority (thousends) of messages are news-letters, order confirmations, etc. + + * `^X-Mailer` starts with `PHP`. This should catch both `X-Mailer: PHP/5.5.0` and `X-Mailer: PHPmailer blah blah`. The same as `JavaMail` applies. + + * `X-Library` presence; only [Indy][6] seems to set this. + + * `X-Mailer` starts with `wdcollect`. Set by some Plesk mails. + + * `X-Mailer` starts with `MIME-tools`. + + + + +### Final precaution: limit the number of replies + +Even when following all of the above advice, you may still encounter an email program that will slip through. This can very dangerous, as email systems that simply `IF email THEN send_email` have the potential to cause infinite email loops. + +For this reason, I recommend keeping track of which emails you’ve sent an autoreply to and rate limiting this to at most n emails in n minutes. This will break the back-and-forth chain. + +We use one email per five minutes, but something less strict will probably also work well. + +### What you need to set on your auto-response + +The specifics for this will vary depending on what sort of mails you’re sending. This is what we use for auto-reply mails: + +``` +Auto-Submitted: auto-replied +X-Auto-Response-Suppress: All +Precedence: auto_reply +``` + +### Feedback + +You can mail me at [martin@arp242.net][7] or [create a GitHub issue][8] for feedback, questions, etc. + +-------------------------------------------------------------------------------- + +via: https://arp242.net/weblog/autoreply.html + +作者：[Martin Tournoij][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://arp242.net/ +[b]: https://github.com/lujun9972 +[1]: http://tools.ietf.org/html/rfc3834 +[2]: https://msdn.microsoft.com/en-us/library/ee219609(v=EXCHG.80).aspx +[3]: https://tools.ietf.org/html/rfc2919) +[4]: https://support.google.com/mail/answer/6254652?hl=en +[5]: http://www.faqs.org/rfcs/rfc2076.html +[6]: http://www.indyproject.org/index.en.aspx +[7]: mailto:martin@arp242.net +[8]: https://github.com/Carpetsmoker/arp242.net/issues/new diff --git a/sources/tech/20181222 Watch YouTube videos at the Linux terminal.md b/sources/tech/20181222 Watch YouTube videos at the Linux terminal.md new file mode 100644 index 0000000000..e4db6bc039 --- /dev/null +++ b/sources/tech/20181222 Watch YouTube videos at the Linux terminal.md @@ -0,0 +1,80 @@ +[#]: collector: (lujun9972) +[#]: translator: (geekpi) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Watch YouTube videos at the Linux terminal) +[#]: via: (https://opensource.com/article/18/12/linux-toy-youtube-dl) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +Watch YouTube videos at the Linux terminal +====== +Thought video content was just for your GUI? Think again. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-youtube-dl.png?itok=HYR5vU2a) + +We're almost to the end of our 24-day-long Linux command-line toys advent calendar. Hopefully, you've been following along, but if not, start back at [the beginning][1] and work your way through. You'll find plenty of games, diversions, and oddities for your Linux terminal. + +And while you may have seen some toys from our calendar before, we hope there’s at least one new thing for everyone. + +Today we're going to double-down on yesterday's toy, [MPlayer][2], and add in one more, [**youtube-dl**][3]. + +As its name would imply, **youtube-dl** is a command-line utility for downloading YouTube videos, but it can capture video from a number of other sites as well, and it's a really quite full-featured application with [thorough documentation][4] to make video acquisition easy. A note: please don't use **youtube-dl** in any context that would violate the copyright laws in your jurisdiction. + +**youtube-dl** is licensed under a public domain dedication known as [the][5] [Unlicense][5] that's similar to Creative Common's [CC0][6]. There are some interesting [legal opinions][7] out there about where public domain dedication fits into the open source landscape, but it's generally considered compatible with existing open source licenses even by organizations who don't recommend its use. + +In its simplest form, we're going to use **youtube-dl** to grab a video for playback in our terminal. First, [install][8] it using a method appropriate for your distribution. For me, in Fedora, it was packaged in my repositories, so installation was as simple as: + +``` +$ sudo dnf install youtube-dl +``` + +Then, let's grab a video. YouTube allows you to search by license, so today, we're going to take a look at a fireplace [video][9] from [Gemmy's Videos][10] available under a Creative Commons attribution license. For YouTube videos, you can download with the file ID alone, like this, and we'll specify an output file name as well. I intentionally picked a short video, since long videos can get quite large! + +``` +$ youtube-dl pec8P5K4s8c -o fireplace.mp4 +``` + +If you didn't install [MPlayer][2] yesterday, go ahead and do that, and you may need to install **libcaca** for your system as well if you did not install it previously. If you just use MPlayer to launch the video from the command line as-is ( **$** **mplayer fireplace.webm** ), it will play, but in a window all of its own; not exactly what we were going for. + +First, I set my **libcaca** settings to force it to use **ncurses** **** as the display driver, keeping the output in my terminal, with: + +``` +$ export CACA_DRIVER=ncurses +``` + +Then, I zoomed way out in my terminal (the more "pixels", the better), and played the file with the following (forcing the use of **libcaca** and silencing text output from MPlayer): + +``` +$ mplayer -really-quiet -vo caca fireplace.mp4 +``` + +And, there you go! +![](https://opensource.com/sites/default/files/uploads/linux-toy-youtube-dl.gif) + +Do you have a favorite command-line toy that we should have included? It's a little late to submit a suggestion for this year, but we'd still love to feature some cool command-line toys in the new year. Let me know in the comments below, and I'll check it out. And let me know what you thought of today's amusement. + +Be sure to check out yesterday's toy, [Listen to the radio at the Linux terminal][2], and come back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-youtube-dl + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/18/12/linux-toy-boxes +[2]: https://opensource.com/article/18/12/linux-toy-mplayer +[3]: https://rg3.github.io/youtube-dl/ +[4]: https://github.com/rg3/youtube-dl/blob/master/README.md#readme +[5]: https://unlicense.org/ +[6]: https://creativecommons.org/share-your-work/public-domain/cc0/ +[7]: https://opensource.org/faq#public-domain +[8]: https://github.com/rg3/youtube-dl/blob/master/README.md#installation +[9]: https://www.youtube.com/watch?v=pec8P5K4s8c +[10]: https://www.youtube.com/channel/UCwwaepmpWZVDd605MIRC20A diff --git a/sources/tech/20181223 The Linux command line can fetch fun from afar.md b/sources/tech/20181223 The Linux command line can fetch fun from afar.md new file mode 100644 index 0000000000..3b5e77fa27 --- /dev/null +++ b/sources/tech/20181223 The Linux command line can fetch fun from afar.md @@ -0,0 +1,63 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (The Linux command line can fetch fun from afar) +[#]: via: (https://opensource.com/article/18/12/linux-toy-remote) +[#]: author: (Jason Baker https://opensource.com/users/jason-baker) + +The Linux command line can fetch fun from afar +====== +Use these tools to access weather, reading material, and more from remote locations. +![](https://opensource.com/sites/default/files/styles/image-full-size/public/uploads/linux-toy-remote.png?itok=mHm9POPi) + +We're almost to the end of our 24-day-long Linux command-line toys advent calendar. Hopefully, you've been following along, but if not, start back at [the beginning][1] and work your way through. You'll find plenty of games, diversions, and oddities for your Linux terminal. + +And while you may have seen some toys from our calendar before, we hope there’s at least one new thing for everyone. + +Today's toy (or actually, collection of toys) is a little different. So far I've mostly tried to focus on toys that are self-contained, and completely usable under an open source license. But I've gotten some great suggestions from readers which utilize an open source tool to access something remotely that may or may not be open source. Today, I'll round up a few of those. + +The first one is a total classic: use Telnet to watch an ASCII-rendition of Star Wars. Chances are that Telnet is already installed on your system, so all you'll need to do is run: + +``` +$ telnet towel.blinkenlights.nl +``` + +I feel like I first saw this one over a decade ago, so it's a bit amazing to me that it's still alive and online. If you've never watched it, set aside some time and go check it out. You won't regret it. + +![](https://opensource.com/sites/default/files/uploads/linux-toy-star-wars.png) + +Next, Opensource.com contributor [Manuel Dewald][2] suggested a way to fetch your local weather from the terminal. It's easy, and only requires that you have **curl** (or, well, **** **wget** ) installed. + +``` +$ curl wttr.in +``` + +![](https://opensource.com/sites/default/files/uploads/linux-toy-weather.png) + +Finally, while you can spend the holidays reading your favorite sites (including Opensource.com) from your favorite [command-line web browser][3], there are a few of my favorite sites that are more easily browsed with a dedicated client. Two of these include Reddit and Hacker News, for which there are clients that have been recommended to me that you may wish to try, mostly available under open source licenses. I've poked around with [haxor-news][4] (Hacker News) and [rtv][5] (Reddit), and both seem pretty cool. + +Do you have a favorite command-line toy that we should have included? It's a little late to submit a suggestion for this year, but we'd still love to feature some cool command-line toys in the new year. Let me know in the comments below, and I'll check it out. And let me know what you thought of today's amusement. + +Be sure to check out yesterday's toy, [Watch YouTube videos at the Linux terminal][6], and come back tomorrow for another! + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/12/linux-toy-remote + +作者：[Jason Baker][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/jason-baker +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/article/18/12/linux-toy-boxes +[2]: https://opensource.com/users/ntlx +[3]: https://opensource.com/article/16/12/web-browsers-linux-command-line +[4]: https://github.com/donnemartin/haxor-news +[5]: https://github.com/michael-lazar/rtv +[6]: https://opensource.com/article/18/12/linux-toy-youtube-dl diff --git a/sources/tech/20181224 An Introduction to Go.md b/sources/tech/20181224 An Introduction to Go.md new file mode 100644 index 0000000000..b35bc9922e --- /dev/null +++ b/sources/tech/20181224 An Introduction to Go.md @@ -0,0 +1,278 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (An Introduction to Go) +[#]: via: (https://blog.jak-linux.org/2018/12/24/introduction-to-go/) +[#]: author: (Julian Andres Klode https://blog.jak-linux.org/) + +An Introduction to Go +====== + +(What follows is an excerpt from my master’s thesis, almost all of section 2.1, quickly introducing Go to people familiar with CS) + +Go is an imperative programming language for concurrent programming created at and mainly developed by Google, initially mostly by Robert Griesemer, Rob Pike, and Ken Thompson. Design of the language started in 2007, and an initial version was released in 2009; with the first stable version, 1.0 released in 2012 . + +Go has a C-like syntax (without a preprocessor), garbage collection, and, like its predecessors devloped at Bell Labs – Newsqueak (Rob Pike), Alef (Phil Winterbottom), and Inferno (Pike, Ritchie, et al.) – provides built-in support for concurrency using so-called goroutines and channels, a form of co-routines, based on the idea of Hoare’s ‘Communicating Sequential Processes’ . + +Go programs are organised in packages. A package is essentially a directory containing Go files. All files in a package share the same namespace, and there are two visibilities for symbols in a package: Symbols starting with an upper case character are visible to other packages, others are private to the package: + +``` +func PublicFunction() { + fmt.Println("Hello world") +} + +func privateFunction() { + fmt.Println("Hello package") +} +``` + +### Types + +Go has a fairly simple type system: There is no subtyping (but there are conversions), no generics, no polymorphic functions, and there are only a few basic categories of types: + + 1. base types: `int`, `int64`, `int8`, `uint`, `float32`, `float64`, etc. + + 2. `struct` + + 3. `interface` \- a set of methods + + 4. `map[K, V]` \- a map from a key type to a value type + + 5. `[number]Type` \- an array of some element type + + 6. `[]Type` \- a slice (pointer to array with length and capability) of some type + + 7. `chan Type` \- a thread-safe queue + + 8. pointer `*T` to some other type + + 9. functions + + 10. named type - aliases for other types that may have associated methods: + +``` +type T struct { foo int } +type T *T +type T OtherNamedType +``` + +Named types are mostly distinct from their underlying types, so you cannot assign them to each other, but some operators like `+` do work on objects of named types with an underlying numerical type (so you could add two `T` in the example above). + + +Maps, slices, and channels are reference-like types - they essentially are structs containing pointers. Other types are passed by value (copied), including arrays (which have a fixed length and are copied). + +#### Conversions + +Conversions are the similar to casts in C and other languages. They are written like this: + +``` +TypeName(value) +``` + +#### Constants + +Go has “untyped” literals and constants. + +``` +1 // untyped integer literal +const foo = 1 // untyped integer constant +const foo int = 1 // int constant +``` + +Untyped values are classified into the following categories: `UntypedBool`, `UntypedInt`, `UntypedRune`, `UntypedFloat`, `UntypedComplex`, `UntypedString`, and `UntypedNil` (Go calls them basic kinds, other basic kinds are available for the concrete types like `uint8`). An untyped value can be assigned to a named type derived from a base type; for example: + +``` +type someType int + +const untyped = 2 // UntypedInt +const bar someType = untyped // OK: untyped can be assigned to someType +const typed int = 2 // int +const bar2 someType = typed // error: int cannot be assigned to someType +``` + +### Interfaces and ‘objects’ + +As mentioned before, interfaces are a set of methods. Go is not an object-oriented language per se, but it has some support for associating methods with named types: When declaring a function, a receiver can be provided - a receiver is an additional function argument that is passed before the function and involved in the function lookup, like this: + +``` +type SomeType struct { ... } + +func (s *SomeType) MyMethod() { +} + +func main() { + var s SomeType + s.MyMethod() +} +``` + +An object implements an interface if it implements all methods; for example, the following interface `MyMethoder` is implemented by `*SomeType` (note the pointer), and values of `*SomeType` can thus be used as values of `MyMethoder`. The most basic interface is `interface{}`, that is an interface with an empty method set - any object satisfies that interface. + +``` +type MyMethoder interface { + MyMethod() +} +``` + +There are some restrictions on valid receiver types; for example, while a named type could be a pointer (for example, `type MyIntPointer *int`), such a type is not a valid receiver type. + +### Control flow + +Go provides three primary statements for control flow: `if`, `switch`, and `for`. The statements are fairly similar to their equivalent in other C-like languages, with some exceptions: + + * There are no parentheses around conditions, so it is `if a == b {}`, not `if (a == b) {}`. The braces are mandatory. + + * All of them can have initialisers, like this + +`if result, err := someFunction(); err == nil { // use result }` + + * The `switch` statement can use arbitrary expressions in cases + + * The `switch` statement can switch over nothing (equals switching over true) + + * Cases do not fall through by default (no `break` needed), use `fallthrough` at the end of a block to fall through. + + * The `for` loop can loop over ranges: `for key, val := range map { do something }` + + + + +### Goroutines + +The keyword `go` spawns a new goroutine, a concurrently executed function. It can be used with any function call, even a function literal: + +``` +func main() { + ... + go func() { + ... + }() + + go some_function(some_argument) +} +``` + +### Channels + +Goroutines are often combined with channels to provide an extended form of Communicating Sequential Processes . A channel is a concurrent-safe queue, and can be buffered or unbuffered: + +``` +var unbuffered = make(chan int) // sending blocks until value has been read +var buffered = make(chan int, 5) // may have up to 5 unread values queued +``` + +The `<-` operator is used to communicate with a single channel. + +``` +valueReadFromChannel := <- channel +otherChannel <- valueToSend +``` + +The `select` statement allows communication with multiple channels: + +``` +select { + case incoming := <- inboundChannel: + // A new message for me + case outgoingChannel <- outgoing: + // Could send a message, yay! +} +``` + +### The `defer` statement + +Go provides a `defer` statement that allows a function call to be scheduled for execution when the function exits. It can be used for resource clean-up, for example: + +``` +func myFunc(someFile io.ReadCloser) { + defer someFile.close() + /bin /boot /dev /etc /home /lib /lib64 /lost+found /media /mnt /opt /proc /root /run /sbin /srv /sys /tmp /usr /var Do stuff with file */ +} +``` + +It is of course possible to use function literals as the function to call, and any variables can be used as usual when writing the call. + +### Error handling + +Go does not provide exceptions or structured error handling. Instead, it handles errors by returning them in a second or later return value: + +``` +func Read(p []byte) (n int, err error) + +// Built-in type: +type error interface { + Error() string +} +``` + +Errors have to be checked in the code, or can be assigned to `_`: + +``` +n0, _ := Read(Buffer) // ignore error +n, err := Read(buffer) +if err != nil { + return err +} +``` + +There are two functions to quickly unwind and recover the call stack, though: `panic()` and `recover()`. When `panic()` is called, the call stack is unwound, and any deferred functions are run as usual. When a deferred function invokes `recover()`, the unwinding stops, and the value given to `panic()` is returned. If we are unwinding normally and not due to a panic, `recover()` simply returns `nil`. In the example below, a function is deferred and any `error` value that is given to `panic()` will be recovered and stored in an error return value. Libraries sometimes use that approach to make highly recursive code like parsers more readable, while still maintaining the usual error return value for public functions. + +``` +func Function() (err error) { + defer func() { + s := recover() + switch s := s.(type) { // type switch + case error: + err = s // s has type error now + default: + panic(s) + } + } +} +``` + +### Arrays and slices + +As mentioned before, an array is a value type and a slice is a pointer into an array, created either by slicing an existing array or by using `make()` to create a slice, which will create an anonymous array to hold the elements. + +``` +slice1 := make([]int, 2, 5) // 5 elements allocated, 2 initialized to 0 +slice2 := array[:] // sliced entire array +slice3 := array[1:] // slice of array without first element +``` + +There are some more possible combinations for the slicing operator than mentioned above, but this should give a good first impression. + +A slice can be used as a dynamically growing array, using the `append()` function. + +``` +slice = append(slice, value1, value2) +slice = append(slice, arrayOrSlice...) +``` + +Slices are also used internally to represent variable parameters in variable length functions. + +### Maps + +Maps are simple key-value stores and support indexing and assigning. They are not thread-safe. + +``` +someValue := someMap[someKey] +someValue, ok := someMap[someKey] // ok is false if key not in someMap +someMap[someKey] = someValue +``` +-------------------------------------------------------------------------------- + +via: https://blog.jak-linux.org/2018/12/24/introduction-to-go/ + +作者：[Julian Andres Klode][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://blog.jak-linux.org/ +[b]: https://github.com/lujun9972 diff --git a/sources/tech/20181224 Turn GNOME to Heaven With These 23 GNOME Extensions.md b/sources/tech/20181224 Turn GNOME to Heaven With These 23 GNOME Extensions.md new file mode 100644 index 0000000000..e49778eab7 --- /dev/null +++ b/sources/tech/20181224 Turn GNOME to Heaven With These 23 GNOME Extensions.md @@ -0,0 +1,288 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Turn GNOME to Heaven With These 23 GNOME Extensions) +[#]: via: (https://fosspost.org/tutorials/turn-gnome-to-heaven-with-these-23-gnome-extensions) +[#]: author: (M.Hanny Sabbagh https://fosspost.org/author/mhsabbagh) + +Turn GNOME to Heaven With These 23 GNOME Extensions +====== + +GNOME Shell is one of the most used desktop interfaces on the Linux desktop. It’s part of the GNOME project and is considered to be the next generation of the old classic GNOME 2.x interface. GNOME Shell was first released in 2011 carrying a lot of features, including GNOME Shell extensions feature. + +GNOME Extensions are simply extra functionality that you can add to your interface, they can be panel extensions, performance extensions, quick access extensions, productivity extensions or for any other type of usage. They are all free and open source of course; you can install them with a single click **from your web browser** actually. + +### How To Install GNOME Extensions? + +You main way to install GNOME extensions will be via the extensions.gnome.org website. It’s an official platform belonging to GNOME where developers publish their extensions easily so that users can install them in a single click. + +In order to for this to work, you’ll need two things: + + 1. Browser Add-on: You’ll need to install a browser add-on that allows the website to communicate with your local GNOME desktop. You install it from [here for Firefox][1], or [here for Chrome][2] or [here for Opera][3]. + + 2. Native Connector: You still need another part to allow your system to accept installing files locally from your web browser. To install this component, you must install the `chrome-gnome-shell` package. Do not be deceived! Although the package name is containing “chrome”, it also works on Firefox too. To install it on Debian/Ubuntu/Mint run the following command in terminal: + +``` +sudo apt install chrome-gnome-shell +``` + +For Fedora: + +``` +sudo dnf install chrome-gnome-shell +``` + +For Arch: + +``` +sudo pacman -S chrome-gnome-shell +``` + +After you have installed the two components above, you can easily install extensions from the GNOME extensions website. + +### How to Configure GNOME Extensions Settings? + +Many of these extensions do have a settings window that you can access to adjust the preferences of that extension. You must make sure that you have seen its options at least once so that you know what you can possibly do using that extension. + +To do this, you can head to the [installed extensions page on the GNOME website][4], and you’ll see a small options button near every extension that offers one: + +![Screenshot 2018 12 24 20 50 55 41][5] + +Clicking it will display a window for you, from which you can see the possible settings: + +![Screenshot 2018 12 24 20 51 29 43][6] + +Read our article below for our list of recommended extension! + +### General Extensions + +#### 1\. User Themes + +![Screenshot from 2018 12 23 12 30 20 45][7] + +This is the first must-install extension on the GNOME Shell interface, it simply allows you to change the desktop theme to another one using the tweak tool. After installation run gnome-tweak-tool, and you’ll be able to change your desktop theme. + +Installation link: + +#### 2\. Dash to Panel + +![Screenshot from 2018 12 24 21 16 11 47][8] + +Converts the GNOME top bar into a taskbar with many added features, such as favorite icons, moving the clock to right, adding currently opened windows to the panel and many other features. (Make sure not to install this one with some other extensions below which do provide the same functionality). + +Installation link: + +#### 3\. Desktop Icons + +![gnome shell screenshot SSP3UZ 49][9] + +Restores desktop icons back again to GNOME. Still in continues development. + +Installation link: + +#### 4\. Dash to Dock + +![Screenshot from 2018 12 24 21 50 07 51][10] + +If you are a fan of the Unity interface, then this extension may help you. It simply adds a dock to the left/right side of the screen, which is very similar to Unity. You can customize that dock however you like. + +Installation link: + +### Productivity Extensions + +#### 5\. Todo.txt + +![screenshot_570_5X5YkZb][11] + +For users who like to maintain productivity, you can use this extension to add a simple To-Do list functionality to your desktop, it will use the [syntax][12] from todotxt.com, you can add unlimited to-dos, mark them as complete or remove them, change their position beside modifying or taking a backup of the todo.txt file manually. + +Installation link: + +#### 6\. Screenshot Tool + +![Screenshot from 2018 12 24 21 04 14 54][13] + +Easily take a screenshot of your desktop or a specific area, with the possibility of also auto-uploading it to imgur.com and auto-saving the link into the clipboard! Very useful extension. + +Installation link: + +#### 7\. OpenWeather + +![screenshot_750][14] + +If you would like to know the weather forecast everyday then this extension will be the right one for you, this extension will simply add an applet to the top panel allowing you to fetch the weather data from openweathermap.org or forecast.io, it supports all the countries and cities around the world. It also shows the wind and humidity. + +Installation link: + +#### 8 & 9\. Search Providers Extensions + +![Screenshot from 2018 12 24 21 29 41 57][15] + +In GNOME, you can add what’s known as “search providers” to the shell, meaning that when you type something in the search box, you’ll be able to automatically search these websites (search providers) using the same text you entered, and see the results directly from your shell! + +YouTube Search Provider: + +Wikipedia Search Provider: + +### Workflow Extensions + +#### 10\. No Title Bar + +![Screenshot 20181224210737 59][16] + +This extension simply removes the title bar from all the maximized windows, and moves it into the top GNOME Panel. In this way, you’ll be able to save a complete horizontal line on your screen, more space for your work! + +Installation Link: + +#### 11\. Applications Menu + +![Screenshot 2018 12 23 13 58 07 61][17] + +This extension simply adds a classic menu to the “activities” menu on the corner. By using it, you will be able to browse the installed applications and categories without the need to use the dash or the search feature, which saves you time. (Check the “No hot corner” extension below to get a better usage). + +Installation link: + +#### 12\. Places Status Indicator + +![screenshot_8_1][18] + +This indicator will put itself near the left corner of the activities button, it allows you to access your home folder and sub-folders easily using a menu, you can also browse the available devices and networks using it. + +Installation link: + +#### 13\. Window List + +![Screenshot from 2016-08-12 08-05-48][19] + +Officially supported by GNOME team, this extension adds a bottom panel to the desktop which allows you to navigate between the open windows easily, it also include a workspace indicator to switch between them. + +Installation link: + +#### 14\. Frippery Panel Favorites + +![screenshot_4][20] + +This extensions adds your favorite applications and programs to the panel near the activities button, allowing you to access to it more quickly with just 1 click, you can add or remove applications from it just by modifying your applications in your favorites (the same applications in the left panel when you click the activities button will appear here). + +Installation link: + +#### 15\. TopIcons + +![Screenshot 20181224211009 66][21] + +Those extensions restore the system tray back into the top GNOME panel. Very needed in cases of where applications are very much dependent on the tray icon. + +For GNOME 3.28, installation link: + +For GNOME 3.30, installation link: + +#### 16\. Clipboard Indicator + +![Screenshot 20181224214626 68][22] + +A clipboard manager is simply an applications that manages all the copy & paste operations you do on your system and saves them into a history, so that you can access them later whenever you want. + +This extension does exactly this, plus many other cool features that you can check. + +Installation link: + +### Other Extensions + +#### 17\. Frippery Move Clock + +![screenshot_2][23] + +If you are from those people who like alignment a lot, and dividing the panels into 2 parts only, then you may like this extension, what it simply does is moving the clock from the middle of the GNOME Shell panel to the right near the other applets on the panel, which makes it more organized. + +Installation link: + +#### 18\. No Topleft Hot Corner + +If you don’t like opening the dash whenever you move the mouse to the left corner, you can disable it easily using this extension. You can for sure click the activities button if you want to open the dash view (or via the Super key on the keyboard), but the hot corner will be disabled only. + +Installation link: + +#### 19\. No Annoyance + +Simply removes the “window is ready” notification each time a new window a opened. + +Installation link: + +#### 20\. EasyScreenCast + +![Screenshot 20181224214219 71][24] + +If you would like to quickly take a screencast for your desktop, then this extension may help you. By simply just choosing the type of recording you want, you’ll be able to take screencasts any time. You can also configure advanced options for the extension, such as the pipeline and many other things. + +Installation link: + +#### 21\. Removable drive Menu + +![Screenshot 20181224214131 73][25] + +Adds an icon to the top bar which shows you a list of your currently removable drives. + +Installation link: + +#### 22\. BottomPanel + +![Screenshot 20181224214419 75][26] + +As its title says.. It simply moves the top GNOME bar into the bottom of the screen. + +Installation link: + +#### 23\. Unite + +If you would like one extension only to do most of the above tasks, then Unite extension can help you. It adds panel favorites, removes title bar, moves the clock, allows you to change the location of the panel.. And many other features. All using this extension alone! + +Installation link: + +### Conclusion + +This was our list for some great GNOME Shell extensions to try out. Of course, you don’t (and shouldn’t!) install all of these, but just what you need for your own usage. As you can see, you can convert GNOME into any form you would like, but be careful for RAM usage (because if you use more extensions, the shell will consume very much resources). + +What other GNOME Shell extensions do you use? What do you think of this list? + + +-------------------------------------------------------------------------------- + +via: https://fosspost.org/tutorials/turn-gnome-to-heaven-with-these-23-gnome-extensions + +作者：[M.Hanny Sabbagh][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://fosspost.org/author/mhsabbagh +[b]: https://github.com/lujun9972 +[1]: https://addons.mozilla.org/en/firefox/addon/gnome-shell-integration/ +[2]: https://chrome.google.com/webstore/detail/gnome-shell-integration/gphhapmejobijbbhgpjhcjognlahblep +[3]: https://addons.opera.com/en/extensions/details/gnome-shell-integration/ +[4]: https://extensions.gnome.org/local/ +[5]: https://i1.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot_2018-12-24_20-50-55.png?resize=850%2C359&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 42) +[6]: https://i1.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot_2018-12-24_20-51-29.png?resize=850%2C462&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 44) +[7]: https://i2.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-from-2018-12-23-12-30-20.png?resize=850%2C478&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 46) +[8]: https://i0.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-from-2018-12-24-21-16-11.png?resize=850%2C478&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 48) +[9]: https://i2.wp.com/fosspost.org/wp-content/uploads/2018/12/gnome-shell-screenshot-SSP3UZ.png?resize=850%2C492&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 50) +[10]: https://i1.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-from-2018-12-24-21-50-07.png?resize=850%2C478&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 52) +[11]: https://i0.wp.com/fosspost.org/wp-content/uploads/2016/08/screenshot_570_5X5YkZb.png?resize=478%2C474&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 53) +[12]: https://github.com/ginatrapani/todo.txt-cli/wiki/The-Todo.txt-Format +[13]: https://i1.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-from-2018-12-24-21-04-14.png?resize=715%2C245&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 55) +[14]: https://i2.wp.com/fosspost.org/wp-content/uploads/2016/08/screenshot_750.jpg?resize=648%2C276&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 56) +[15]: https://i2.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-from-2018-12-24-21-29-41.png?resize=850%2C478&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 58) +[16]: https://i0.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-20181224210737-380x95.png?resize=380%2C95&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 60) +[17]: https://i0.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot_2018-12-23_13-58-07.png?resize=524%2C443&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 62) +[18]: https://i0.wp.com/fosspost.org/wp-content/uploads/2016/08/screenshot_8_1.png?resize=247%2C620&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 63) +[19]: https://i1.wp.com/fosspost.org/wp-content/uploads/2016/08/Screenshot-from-2016-08-12-08-05-48.png?resize=850%2C478&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 64) +[20]: https://i0.wp.com/fosspost.org/wp-content/uploads/2016/08/screenshot_4.png?resize=414%2C39&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 65) +[21]: https://i0.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-20181224211009-631x133.png?resize=631%2C133&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 67) +[22]: https://i1.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-20181224214626-520x443.png?resize=520%2C443&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 69) +[23]: https://i0.wp.com/fosspost.org/wp-content/uploads/2016/08/screenshot_2.png?resize=388%2C26&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 70) +[24]: https://i2.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-20181224214219-327x328.png?resize=327%2C328&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 72) +[25]: https://i1.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-20181224214131-366x199.png?resize=366%2C199&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 74) +[26]: https://i2.wp.com/fosspost.org/wp-content/uploads/2018/12/Screenshot-20181224214419-830x143.png?resize=830%2C143&ssl=1 (Turn GNOME to Heaven With These 23 GNOME Extensions 76) diff --git a/sources/tech/20181226 -Review- Polo File Manager in Linux.md b/sources/tech/20181226 -Review- Polo File Manager in Linux.md new file mode 100644 index 0000000000..cf763850cf --- /dev/null +++ b/sources/tech/20181226 -Review- Polo File Manager in Linux.md @@ -0,0 +1,139 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: ([Review] Polo File Manager in Linux) +[#]: via: (https://itsfoss.com/polo-file-manager/) +[#]: author: (John Paul https://itsfoss.com/author/john/) + +[Review] Polo File Manager in Linux +====== + +We are all familiar with file managers. It’s that piece of software that allows you to access your directories, files in a GUI. + +Most of us use the default file manager included with our desktop of choice. The creator of [Polo][1] hopes to get you to use his file manager by adding extra features but hides the good ones behind a paywall. + +![][2]Polo file manager + +### What is Polo file manager? + +According to its [website][1], Polo is an “advanced file manager for Linux written in [Vala][3])”. Further down the page, Polo is referred to as a “modern, light-weight file manager for Linux with support for multiple panes and tabs; support for archives, and much more.” + +It is from the same developer (Tony George) that has given us some of the most popular applications for desktop Linux. [Timeshift backup][4] tool, [Conky Manager][5], [Aptik backup tool][6]s for applications etc. Polo is the latest offering from Tony. + +Note that Polo is still in the beta stage of development which means the first stable version of the software is not out yet. + +### Features of Polo file manager + +![Polo File Manager in Ubuntu Linux][7]Polo File Manager in Ubuntu Linux + +It’s true that Polo has a bunch of neat features that most file managers don’t have. However, the really neat features are only available if you donate more than $10 to the project or sign up for the creator’s Patreon. I will be separating the free features from the features that require the “donation plugin”. + +![Cloud storage support in Polo file manager][8]Support cloud storage + +#### Free Features + + * Multiple Panes – Single-pane, dual-pane (vertical or horizontal split) and quad-pane layouts. + * Multiple Views – List view, Icon view, Tiled view, and Media view + * Device Manager – Devices popup displays the list of connected devices with options to mount and unmount + * Archive Support – Support for browsing archives as normal folders. Supports creation of archives in multiple formats with advanced compression settings. + * Checksum & Hashing – Generate and compare MD5, SHA1, SHA2-256 ad SHA2-512 checksums + * Built-in [Fish shell][9] + * Support for [cloud storage][10], such as Dropbox, Google Drive, Amazon Drive, Amazon S3, Backblaze B2, Hubi, Microsoft OneDrive, OpenStack Swift, and Yandex Disk + * Compare files + * Analyses disk usage + * KVM support + * Connect to FTP, SFTP, SSH and Samba servers + + + +![Dual pane view of Polo file manager][11]Polo in dual pane view + +#### Donation/Paywall Features + + * Write ISO to USB Device + * Image optimization and adjustment tools + * Optimize PNG + * Reduce JPEG Quality + * Remove Color + * Reduce Color + * Boost Color + * Set as Wallpaper + * Rotate + * Resize + * Convert to PNG, JPEG, TIFF, BMP, ICO and more + * PDF tools + * Split + * Merge + * Add and Remove Password + * Reduce File Size + * Uncompress + * Remove Colors + * Rotate + * Optimize + * Video Download via [youtube-dl][12] + + + +### Installing Polo + +Let’s see how to install Polo file manager on various Linux distributions. + +#### 1\. Ubuntu based distributions + +For all Ubuntu based systems (Ubuntu, Linux Mint, Elementary OS, etc), you can install Polo via the [official PPA][13]. Not sure what a PPA is? [Read about PPA here][14]. + +`sudo apt-add-repository -y ppa:teejee2008/ppa` +`sudo apt-get update` +`sudo apt-get install polo-file-manager` + +#### 2\. Arch based distributions + +For all Arch-based systems (Arch, Manjaro, ArchLabs, etc), you can install Polo from the [Arch User Repository][15]. + +#### 3\. Other Distros + +For all other distros, you can download and use the [.RUN installer][16] to setup Polo. + +### Thoughts on Polo + +I’ve installed tons of different distros and never had a problem with the default file manager. (I’ve probably used Thunar and Caja the most.) The free version of Polo doesn’t contain any features that would make me switch. As for the paid features, I already use a number of applications that accomplish the same things. + +One final note: the paid version of Polo is supposed to help fund development of the project. However, [according to GitHub][17], the last commit on Polo was three months ago. That’s quite a big interval of inactivity for a software that is still in the beta stages of development. + +Have you ever used [Polo][1]? If not, what is your favorite Linux file manager? Let us know in the comments below. + +If you found this article interesting, please take a minute to share it on social media, Hacker News or [Reddit][18]. + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/polo-file-manager/ + +作者：[John Paul][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/john/ +[b]: https://github.com/lujun9972 +[1]: https://teejee2008.github.io/polo/ +[2]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/12/polo.jpg?fit=800%2C500&ssl=1 +[3]: https://en.wikipedia.org/wiki/Vala_(programming_language +[4]: https://itsfoss.com/backup-restore-linux-timeshift/ +[5]: https://itsfoss.com/conky-gui-ubuntu-1304/ +[6]: https://github.com/teejee2008/aptik +[7]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/12/polo-file-manager-in-ubuntu.jpeg?resize=800%2C450&ssl=1 +[8]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/polo-coud-options.jpg?fit=800%2C795&ssl=1 +[9]: https://fishshell.com/ +[10]: https://itsfoss.com/cloud-services-linux/ +[11]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/polo-dual-pane.jpg?fit=800%2C520&ssl=1 +[12]: https://itsfoss.com/download-youtube-linux/ +[13]: https://launchpad.net/~teejee2008/+archive/ubuntu/ppa +[14]: https://itsfoss.com/ppa-guide/ +[15]: https://aur.archlinux.org/packages/polo +[16]: https://github.com/teejee2008/polo/releases +[17]: https://github.com/teejee2008/polo +[18]: http://reddit.com/r/linuxusersgroup diff --git a/translated/talk/20180409 5 steps to building a cloud that meets your users- needs.md b/translated/talk/20180409 5 steps to building a cloud that meets your users- needs.md deleted file mode 100644 index 09ac1aced2..0000000000 --- a/translated/talk/20180409 5 steps to building a cloud that meets your users- needs.md +++ /dev/null @@ -1,108 +0,0 @@ - -构建满足客户需求的一套云环境的5个步骤 -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/rh_003601_05_mech_osyearbook2016_cloud_cc.png?itok=XSV7yR9e) -这篇文是和[Ian Teksbury][1]共同完成的。 - -无论你如何定义，云就是你的用户展现组织价值的另一个工具。当谈论新的范例或者技术的时候是很容易被，(云是两者兼有)它的新特性所分心。由一系列无止境的问题引发的对话能够很快的被发展为功能愿景清单，所有的这些都是你可能已经考虑到的。 - * 是公有云，私有云还是混合云？ - * 将会使用虚拟机还是容器，或者是两者？ - * 将会提供自助服务吗？ - * 将会完全自动的从开发转移到生产，还是它将需要手动操作？ - * 我们能以多块的速度创建？ - * 关于工具X,Y,还有Z？ - -这样的清单还可以列举很多。 - -开始现代化，或者数字转型，无论你是如何称呼的，通常方法是开始回答高级管理层的一些高层次问题，这种方法的结果是可以预想到的：失败。经过大范围的调研并且花费了数月的时间，如果不是几年，部署这个最炫的新技术，新的云技术从未被使用过而且陷入了荒废直到它最终被丢弃或者遗忘在数据中心的一角和预算中。 - -因为无论你交付的是什么工具都不是用户所想要或者需要的。更加糟糕的是，当用户真正需要的是一个单独的工具时，一系列其他的工具就会被用户抛弃因为新的,闪光的 -升级的工具能够更好的满足他们的需求。 - -### 议题聚焦 - -问题是关注，传统一直是关注工具。但工具并不是要增加到组织价值中的东西；终端用户利用它做什么。你需要将你的注意力从创建云(列入技术和工具)转移到你的人员和用户身上。 - -事实上，使用工具的用户(而不是工具本身)是驱动价值的因素，聚焦注意力在用户身上也是由其他原因的。工具是给用户使用去解决他们的问题并允许他们创造价值的， -所有这就导致了如果那些工具不能满足那些用户的需求，那么那些工具将不会被使用。如果你交付给你的用户的工具并不是他们喜欢的，他们将不会使用，这就是人类的 -人性行为。 - -数十年来，IT产业只为用户提供一种解决方案，因为仅有一个或两个选项，用户是没有权力去改变的。现在情况已经不同了。我们现在生活在一个技术选择的世界中。 -不给用户一个选择的机会的情况将不会被接受的；他们在个人的科技生活中有选择，同时希望在工作中也有选择。现在的用户都是受过教育的并且知道将会有比你提供的机会更好的选择。 - -因此，在物理上的最安全的地点之外，没有能够阻止他们只做他们自己想要的东西的方法，我们称之为“影子IT。”如果你的组织由如此严格的安全策略和承诺策略，许多员工将会感到灰心丧气并且会离职去其他能提供更好机会的公司。 - -基于以上所有的原因，你必须牢记要首先和你的终端用户设计你的昂贵又费时的云项目。 - -### 创建满足用户需求的云五个步骤的过程 - -既然我们已经知道了为什么，接下来我们来讨论一下怎么做。你如何去为终端用户创建一个云？你怎样重新将你的注意力从技术转移到使用技术的用户身上？ -根据以往的经验，我们知道最好的方法中包含两件重要的事情：从你的用户中得到及时的反馈，创建中和用户进行更多的互动。 - -你的云环境将继续随着你的组织不段发展。下面的五个步骤将会帮助你创建满足用户需求的云环境。 - -### 1\. 识别谁将是你的用户 - -在你开始询问用户问题之前，你首先必须识别谁将是你的新的云环境的用户。他们可能包括将在云上创建开发应用的开发者。也可能是运营，维护或者或者创建云的运维团队；还可能是保护组织的安全团队。在第一次迭代时，将你的用户数量缩小至人数较少的小组防止你被大量的反馈所淹没，让你识别的每个小组指派两个代表(一个主要的一个辅助的)。这将使你的第一次交付在大小和时间上都很小。 - -#### 2\. 和你的用户面对面的交谈来收获有价值的输入。 - -The best way to get users' feedback is through direct communication. Mass emails asking for input will self-select respondents—if you even get a response. Group discussions can be helpful, but people tend to be more candid when they have a private, attentive audience. -获得反馈的最佳途径是和用户直接交谈。如果你收到回复，大量的邮件要求你输入信息，你会选择自动回复。小组讨论会很有帮助的，但是当人们有私密的，吸引人注意的观众，他们会比较的坦诚。 - -和你的第一批用户安排面对面的个人的会谈并且向他们询问以下的问题： - - * 为了完成你的任务，你需要什么？ - * 为了完成你的任务，你想要什么？ - * 你现在最头疼的技术点是什么？ - * 你现在最头疼的政策或者程序是哪个？ - * 为了满足你的需求你有什么想法，欲望还是疼痛？ - -这些问题只是指导性的并不一定适合每个组。你不应该只询问这些问题，他们应该导向更深层次的讨论。确保告诉用户任何所说的和被问的都会被反馈的。所有的反馈都是有帮助的，无论是消极的还是积极的。这些对话将会帮助你设置你的开发优先级。 - -收集这种个性化的反馈是保持初始用户群较小的另一个原因：将会花费你大量的时间来和每个用户交流，但是我们已经发现这是相当值得付出的投入。 - -#### 3\. 设计并交付你的解决方案的第一个版本 - -一旦你收到初始用户的反馈，就是时候开始去设计并交付一部分的功能了。我们不推荐尝试一次性交付整个解决方案。设计和交付的时期要短；这是为了避免犯一个需要你花费一年的时间去寻找解决方案的错误，只会让你的用户拒绝它，因为对他们来说毫无用处。创建你的云所需要的工具取决于你的组织和它的特殊需求。只需确保你的解决方案是建立在用户的反馈的基础上的，你将功能小块化的交付并且要经常的去征求用户的反馈。 - -#### 4\. 询问用户对第一个版本的反馈 - -太棒了，现在你已经设计并向你的用户交付了你的炫酷的新的云环境的第一个版本！你并不是花费一整年去完成它而是将它处理成小的模块。为什么将其分为小的模块如此重要呢？因为你要回归你的用户并且向他们收集关于你的设计和交付的功能。他们喜欢什么？不喜欢什么?你正确的处理了他们所关注的吗？是技术功能上很厉害，但系统进程或者策略方面仍然欠缺？ - -再重申一次，你要问的问题取决于你的组织；这里的关键是继续前一个阶段的讨论。毕竟你正在为用户创建云环境，所以确保它对用户来说是有用的并且能够有效利用每个人的时间。 - -#### 5\. 回到第一步。 - -这是一个互动的过程。你的第一次交付应该是快速而小规模的，而且以后的迭代也应该是这样的。不要期待仅仅按照这个流程完成了一次，两次即使是三次就能完成。 -一旦你持续的迭代，你将会吸引更多的用户从而能够在这个过程中得到更好的回报。你将会从用户那里得到更多的支持。你能狗迭代的更迅速并且更可靠。到最后，你 -将会通过改变你的进程来满足用户的需求。 - -用户是这个过程中最重要的一部分，但迭代是第二重要的因为它让你能够回到用户中进行持续沟通从而得到更多有用的信息。在每个阶段，记录那些是有效的哪些没有起到应有的效果。要自省，要对自己诚实。我们所花费的时间提供了最有价值的了吗？如果不是，在下一个阶段尝试些不同的。在每次循环中不要花费太多时间的重要部分是，如果某部分在这次不起作用，你能够很容易的在写一次中调整它，知道你找到能够在你组织中起作用的方法。 - -### 这仅仅是开始 - -通过许多客户的约定，从他们那里收集反馈，以及在这个领域的同行的经验，我们一次次的发现在你创建云的时候最重要事就是和你的用户交谈。这看起来是很明显的， -但很让人惊讶的是很多组织却偏离了这个方向去花费数月或者数年的时间去创建，然后最终发现它对终端用户甚至一点用处都没有。 - -现在你已经知道为什么你需要将你的注意力集中到终端用户身上并且在中心节点和用户有一个一起创建云的互动过程。剩下的是我们所喜欢的部分，你出去做的部分。 - -这篇文章是基于"[为终端用户设计混合云或者失败]，"一篇作者将在[Red Hat Summit 2018][3]上发表的文章，并且将于5月8日至10日在旧金山举行 - -[在5月7号前注册][3]将会节省US$500。在支付页面使用折扣码**OPEN18**将会享受到折扣。 --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/4/5-steps-building-your-cloud-correctly - -作者：[Cameron Wyatt][a] -译者：[FelixYFZ](https://github.com/FelixYFZ) -校对：[校对者ID](https://github.com/校对者ID) -选题：[lujun9972](https://github.com/lujun9972) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/cameronmwyatt -[1]:https://opensource.com/users/itewk -[2]:https://agenda.summit.redhat.com/SessionDetail.aspx?id=154225 -[3]:https://www.redhat.com/en/summit/2018 diff --git a/translated/talk/20180817 Mixing software development roles produces great results.md b/translated/talk/20180817 Mixing software development roles produces great results.md deleted file mode 100644 index d753f6f027..0000000000 --- a/translated/talk/20180817 Mixing software development roles produces great results.md +++ /dev/null @@ -1,71 +0,0 @@ -混合软件开发角色效果更佳 -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/checklist_hands_team_collaboration.png?itok=u82QepPk) - -大多数开源社区没有很多正式的角色。当然, 也有一些固定人员帮助处理系统管理员任务、测试、编写文档以及翻译或开发代码。但开源社区的人员通常在不同的角色之间流动, 往往同时履行几个角色的职责。 - -相反, 大多数传统公司的团队成员都定义了角色,例如, 负责文档、技术支持、质量检验和其他领域。 - -为什么开源社区采取共享角色的方法, 更重要的是, 这种协作方式如何影响产品和客户？ - -[Nextcloud][1] 采用了这种社区式的混合角色的做法, 我们看到了我们的客户和用户受益颇多。 - -### 1\.更好的产品测试 - - 任何测试人员都会说测试是一项困难的工作。你需要了解工程师开发的产品, 并且需要设计测试案例、执行测试案例并将结果返回给开发人员。完成该过程后, 开发人员将进行更改, 然后重复该过程, 根据需要来回进行多次,直到任务完成。 - -在社区中, 贡献者通常会对他们开发的项目负责, 因此他们会对这些项目进行广泛的测试和记录, 然后再将其交给用户。贴近项目的用户通常会与开发人员协作, 帮助测试、翻译和编写文档。这将创建一个更紧密、更快的反馈循环, 从而加快开发速度并提高质量。 - -当开发人员不断面对他们的工作结果时, 它鼓励他们以最大限度地减少测试和调试的方式去书写。自动化测试是开发中的一个重要元素, 反馈循环可以确保正确地完成操作: 开发人员主观能动的来实现自动化--而不过于简化也不过于复杂。当然, 他们可能希望别人做更多的测试或自动化的测试 但当测试是正确的选择时, 他们就会这样做。此外, 他们还审查对方的代码, 因为他们知道问题往往会在以后让他们付出代价。 - -因此, 虽然我不认为放弃专用测试人员更好, 但在没有社区志愿者进行测试的项目中, 测试人员应该是开发人员, 并密切嵌入到开发团队中。结果如何？客户得到的产品是由100% 有动机的人测试和开发的, 以确保它是稳定和可靠的。 - -### 2\. 开发和客户需求之间的密切协作 - -要使产品开发与客户需求保持一致是非常困难的。每个客户都有自己独特的需求, 有长期和短期的因素需要考虑--当然, 作为一家公司, 你对你的方向有想法。你如何整合所有这些想法和愿景？ - -公司通常创建与工程和产品开发分开的角色, 如产品管理、支持、质量检测等。这背后的想法是, 人们在专攻的时候做得最好, 工程师不应该为测试或支持等 "简单" 的任务而烦恼。 - -实际上, 这种角色分离是一项削减成本的措施。它使管理层能够进行微观管理, 并更能掌握全局, 因为他们可以简单地进行产品管理, 例如, 确定路线图项目的优先次序。(它还创建了更多的会议!) - -另一方面, 在社区, "决定权在工作者手上"。开发人员通常也是用户 (或由用户支付报酬), 因此他们自然地与用户的需求保持一致。当用户帮助进行测试时 (如上所述), 开发人员会不断地与他们合作, 因此双方都完全了解什么是可行的, 什么是需要的。 - -这种开放的合作方式使用户和项目紧密协作。在没有管理层干涉和指手画脚的情况下, 用户最迫切的需求可以迅速得到满足, 因为工程师已经非常了解这些需求。 - -在 nextcloud 中, 客户永远不需要解释两次, 也不需要依靠初级支持团队成员将问题准确地传达给工程师。我们的工程师根据客户的实际需求不断调整他们的优先级。同时, 基于对客户的深入了解, 合作制定长期目标。 - -### 3\. 最佳支持 - -与专有的或 [open core][2]（开放源核心）的开发商不同, 开源供应商有强大的动力提供尽可能最好的支持: 它是与其他公司在其生态系统中的关键区别。 - -为什么项目背后有动力？—比如 [Collabora][3] 在 [LibreOffice][4] 背后, [The Qt Company][5] 在 [Qt][6] 背后, 或者 [Red Hat][7] 在 [RHEL][8] 背后—最佳来源于客户的支持？ - -当然, 直接接触工程师。许多公司并阻断工程的支持, 而是为客户提供了获得工程师专业知识的机会。这有助于确保客户始终尽快获得最佳答案。虽然一些工程师可能比其他人在支持上花费更多的时间, 但整个工程团队在客户成功方面发挥着作用。自营供应商可能会为客户提供一个专门的现场工程师, 费用相当高, 例如,但一个开源公司, 如 [OpenNMS][9] 在您的支持合同中提供相同级别的服务, 即使您不是财富500强客户也是如此。 - -还有一个好处, 那就是与测试和客户协作有关: 共享角色可确保工程师每天处理客户问题和愿望, 从而促使他们快速解决最常见的问题。他们还倾向于构建额外的工具和功能, 以满足客户预期。 - -简单地说, 将 质量检测、支持、产品管理和其他工程角色合并为一个团队, 可确保优秀开发人员的三大优点--[laziness, impatience, and hubris][10](从简，精益求精，高度自我要求)—与客户紧密保持一致。 - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/8/mixing-roles-engineering - -作者：[Jos Poortvliet][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[lixinyuxx](https://github.com/lixinyuxx) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/jospoortvliet -[1]:https://nextcloud.com/ -[2]:https://en.wikipedia.org/wiki/Open_core -[3]:https://www.collaboraoffice.com/ -[4]:https://www.libreoffice.org/ -[5]:https://www.qt.io/ -[6]:https://www.qt.io/developers/ -[7]:https://www.redhat.com/en -[8]:https://www.redhat.com/en/technologies/linux-platforms/enterprise-linux -[9]:https://www.opennms.org/en -[10]:http://threevirtues.com/ diff --git a/translated/tech/20180314 Protecting Code Integrity with PGP - Part 5- Moving Subkeys to a Hardware Device.md b/translated/tech/20180314 Protecting Code Integrity with PGP - Part 5- Moving Subkeys to a Hardware Device.md new file mode 100644 index 0000000000..8dadad1193 --- /dev/null +++ b/translated/tech/20180314 Protecting Code Integrity with PGP - Part 5- Moving Subkeys to a Hardware Device.md @@ -0,0 +1,304 @@ +用 PGP 保护代码完整性（五）：将子密钥移到一个硬件设备中 +====== + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/pgp-keys.jpg?itok=aS6IWGpq) + +在本系列教程中，我们将提供一个使用 PGP 的实用指南。如果你没有看过前面的文章，你可以通过下面的链接去查看。在这篇文章中，我们将继续讨论如何保护你的密钥，谈一谈将你的子密钥移到一个专门的硬件设备中的一些技巧。 + +[第一部分：基本概念和工具][1] + +[第二部分：生成你的主密钥][2] + +[第三部分：生成 PGP 子密钥][3] + +[第四部分：将主密钥移到离线存储中][4] + +### 清单 + + * 取得一个 GnuPG 兼容的硬件设备（必要） + + * 配置 GnuPG 在设备上工作（必要） + + * 设置 user 和 admin 的 PIN（必要） + + * 移动子密钥到设备中（必要） + + + + +### 考虑事项 + +虽然现在主密钥已经不用担心泄露或失窃了，但子密钥仍然在你的 Home 目录中。任何得到它的人都能够解密你的通讯或假冒你的签名（如果他们知道密钥的密码）。并且，每次执行一个 GnuPG 操作都要将密钥加载到操作系统内存中，这将使一些更高级的恶意软件有机会得到你的密钥（想想 Meltdown 和 Spectre）。 + +完全保护密钥的最好方式就是，将它移到一个专门的硬件设备中，这种硬件设备是一个可操作的智能卡。 + +#### 智能卡的好处 + +一个智能卡包含一个加密芯片，它能够存储私钥，并且直接在智能卡内部执行秘密操作。因为密钥内容从来没有离开过智能卡，计算机操作系统并不能检索你插入的智能卡上的私钥。这与前面用于备份目的的加密 USB 存储是不同的 —— 虽然 USB 设备也是插入并解密的，但操作系统是能够去访问私钥内容的。使用外置的加密 USB 介质并不能代替智能卡设备的功能。 + +智能卡的一些其它好处： + + * 它们很便宜且易于获得 + + * 它们小巧且易于携带 + + * 它们可以用于多种设备上 + + * 它们中的很多都具有防篡改功能（取决于制造商） + + + + +#### 可用的智能卡设备 + +智能卡最初是嵌入到真实钱包大小的卡中，故而得名智能卡。你总是可以买到并使用 GnuPG 功能的智能卡，并且它们是你能得到的最便宜的可用设备之一。但是，事实上智能卡有一个很重要的缺点：它们需要一个智能卡读卡器，只有极小数的笔记本电脑上有这种读卡器。 + +由于这个原因，制造商开始推出小型 USB 设备，它的大小和 U 盘类似，内置有微型智能卡，并且在芯片上简单地实现了智能卡协议特性。下面推荐几个这样的设备： + + * [Nitrokey Start][5]：开源硬件和自由软件，可用于 GnuPG 的最便宜的选择之一，但是额外的安全特性很少。 + + * [Nitrokey Pro][6]：类似于 Nitrokey Start，它提供防篡改及更多的安全特性（但没有 U2F，具体查看指南的 U2F 节）。 + + * [Yubikey 4][7]：专利硬件和软件，但比 Nitrokey Pro 便宜，并且可以用在最新的笔记本电脑上的 USB-C 接口；也提供像 U2F 这样的额外的安全特性。 + + + + +我们推荐选一个同时具备智能卡功能和 U2F 的设备，在写这篇文章时，只能选择 Yubikey 4。 + +#### 配置智能卡设备 + +你的智能卡设备插入任何一台现代的 Linux 或 Mac 工作站上都应该能正常工作。你可以通过运行如下的命令去验证它： +``` +$ gpg --card-status + +``` + +如果你没有收到错误，有一个完整的卡列表，就表示一切正常。不幸的是，排除为什么设备不能正常工作的所有可能原因，已经超出了本指南的范围。如果你的智能卡使用 GnuPG 时有问题，请通过你的操作系统的常见支持通道寻求支持。 + +##### PIN 不一定是数字 + +注意，尽管名为 “PIN”（暗示你它必须是一个“数字”），不论是 user PIN 还是 admin PIN 都不必非要是数字。 + +当你收到一个新设备时，它可能设置有一个默认的 user 和 admin PIN，对于 Yubikeys，它分别是 123456 和 12345678。如果它们的 PIN 不是默认的，请查看设备附带的说明书。 + +##### 快速设置 + +为配置你的智能卡，你需要使用 GnuPG 菜单系统，因此这里并没有更方便的命令行开关： +``` +$ gpg --card-edit +[...omitted...] +gpg/card> admin +Admin commands are allowed +gpg/card> passwd + +``` + +你应该去设置 user PIN (1)、admin PIN (3)、和 Reset Code (4)。请确保把它们记录并保存到一个安全的地方 —— 尤其是 Admin PIN 和 Reset Code（它允许你去擦除整个智能卡内容）。你很少使用到 Admin PIN，因此如果你不记录下来，很可能会忘掉它。 + +返回到智能卡主菜单，你也可以设置其它值（比如名字、性别、登入日期、等等），但是这些都不是必需的，一旦你的智能卡丢失了，将导致额外的信息泄露。 + +#### 将子密钥移到你的智能卡中 + +退出卡菜单（使用 “q” 命令）保存所有更改。接下来，我们将你的子密钥移到智能卡中。将需要用到你的 PGP 密钥的密码，在大多数的智能卡操作中都将用到 admin PIN。记住，那个 [fpr] 表示你的密钥的完整的 40 个字符的指纹。 +``` +$ gpg --edit-key [fpr] + +Secret subkeys are available. + +pub rsa4096/AAAABBBBCCCCDDDD + created: 2017-12-07 expires: 2019-12-07 usage: C + trust: ultimate validity: ultimate +ssb rsa2048/1111222233334444 + created: 2017-12-07 expires: never usage: E +ssb rsa2048/5555666677778888 + created: 2017-12-07 expires: never usage: S +[ultimate] (1). Alice Engineer +[ultimate] (2) Alice Engineer + +gpg> + +``` + +使用 --edit-key 再次进入到菜单模式，你将注意到那个密钥清单有一点小差别。从现在开始，所有的命令都是在这个菜单模式下运行，它用 gpg> 提示符来表示。 + +首先，我们来选择移到智能卡中的密钥 —— 你可以通过键入 `key 1`（它表示选择清单中的第一个密钥）来实现： +``` +gpg> key 1 + +``` + +这个输出会有一点细微的差别： +``` +pub rsa4096/AAAABBBBCCCCDDDD + created: 2017-12-07 expires: 2019-12-07 usage: C + trust: ultimate validity: ultimate +ssb* rsa2048/1111222233334444 + created: 2017-12-07 expires: never usage: E +ssb rsa2048/5555666677778888 + created: 2017-12-07 expires: never usage: S +[ultimate] (1). Alice Engineer +[ultimate] (2) Alice Engineer + +``` + +注意与密钥对应的 ssb 行旁边的 `*` —— 它表示这是当前选定的密钥。它是可切换的，意味着如果你再次输入 `key 1`，这个 `*` 将消失，这个密钥将不再被选中。 + +现在，我们来将密钥移到智能卡中： +``` +gpg> keytocard +Please select where to store the key: + (2) Encryption key +Your selection? 2 + +``` + +由于它是我们的 [E] 密钥，把它移到加密区中是有很有意义的。当你提交了你的选择之后，将会被提示输入你的 PGP 密钥的保护密码，接下来输入智能卡的 admin PIN。如果命令没有返回错误，表示你的密钥已经被移到智能卡中了。 + +**重要：** 现在再次输入 `key 1` 去取消选中第一个密钥，并输入 `key 2` 去选择 [S] 密钥： + +``` +gpg> key 1 +gpg> key 2 +gpg> keytocard +Please select where to store the key: + (1) Signature key + (3) Authentication key +Your selection? 1 + +``` + +你可以使用 [S] 密钥同时做签名和验证，但是我们希望确保它在签名区，因此，我们选择 (1)。完成后，如果你的命令没有返回错误，表示操作已成功。 + +最后，如果你创建了一个 [A] 密钥，你也可以将它移到智能卡中，但是你需要先取消选中 `key 2`。完成后，选择 “q"： +``` +gpg> q +Save changes? (y/N) y + +``` + +保存变更将把你的子密钥移到智能卡后，把你的 Home 目录中的相应子密钥删除（没有关系，因为我们的备份中还有，如果更换了智能卡，你需要再做一遍）。 + +##### 验证移动后的密钥 + +现在，如果你执行一个` --list-secret-keys` 操作，你将看到一个稍有不同的输出： +``` +$ gpg --list-secret-keys +sec# rsa4096 2017-12-06 [C] [expires: 2019-12-06] + 111122223333444455556666AAAABBBBCCCCDDDD +uid [ultimate] Alice Engineer +uid [ultimate] Alice Engineer +ssb> rsa2048 2017-12-06 [E] +ssb> rsa2048 2017-12-06 [S] + +``` + +在 ssb> 的输出中的 `>` 表示子密钥仅在智能卡上有效。如果你进入到你的密钥目录中，查看目录的内容，你将会看到那个 `.key` 文件已经被存根替换： +``` +$ cd ~/.gnupg/private-keys-v1.d +$ strings *.key + +``` + +这个输出将包含一个影子私钥，它表示那个文件仅是个存根，真正的内容在智能卡中。 + +#### 验证智能卡的功能 + +验证智能卡能否如期正常运行，你可以通过创建一个签名来验证： +``` +$ echo "Hello world" | gpg --clearsign > /tmp/test.asc +$ gpg --verify /tmp/test.asc + +``` + +首次运行这个命令时将询问你智能卡的 PIN，在你运行 `gpg —verify` 之后，它将显示 "Good signature”。 + +祝贺你，你已经成功将窃取你的开发者数字身份变得更加困难了！ + +### 其它常见 GnuPG 操作 + +下面是使用你的 PGP 密钥需要做的一些常见操作的快速指南。 + +在下面的所有命令中，[fpr] 表示你的密钥指纹。 + +#### 挂载主密钥离线存储 + +下面的一些操作将需要你的主密钥，因此首先需要去挂载你的主密钥离线存储，并告诉 GnuPG 去使用它。首先，找出介质挂载路径，可以通过查看 mount 命令的输出找到它。接着，设置你的 GnuPG 目录为你的介质上备份的目录，并告诉 GnuPG 将那个目录做为它的 Home： +``` +$ export GNUPGHOME=/media/disk/name/gnupg-backup +$ gpg --list-secret-keys + +``` + +确保你在输出中看到的是 `sec` 而不是 `sec#`（这个 `#` 表示密钥不可用，仍然使用的是惯常的那个 Home 目录）。 + +##### 更新你惯常使用的那个 GnuPG 工作目录 + +在你的离线存储上做了任何更改之后，你应该将这些更改同步应用到你惯常使用的工作目录中： +``` +$ gpg --export | gpg --homedir ~/.gnupg --import +$ unset GNUPGHOME + +``` + +#### 延长密钥过期日期 + +我们创建的主密钥的默认过期日期是自创建之日起两年后。这样做都是为安全考虑，这样将使淘汰密钥最终从密钥服务器上消失。 + +延长你的密钥过期日期，从当前日期延长一年，只需要运行如下命令： +``` +$ gpg --quick-set-expire [fpr] 1y + +``` + +如果为了好记住，你也可以使用一个特定日期（比如，你的生日、1 月 1 日、或加拿大国庆日）： +``` +$ gpg --quick-set-expire [fpr] 2020-07-01 + +``` + +记得将更新后的密钥发送到密钥服务器： +``` +$ gpg --send-key [fpr] + +``` + +#### 吊销身份 + +如果你需要吊销一个身份（比如，你换了雇主并且旧的邮件地址不再有效了），你可以使用一行命令搞定： +``` +$ gpg --quick-revoke-uid [fpr] 'Alice Engineer ' + +``` + +你也可以通过使用 `gpg --edit-key [fpr]` 在菜单模式下完成同样的事情。 + +完成后，记得将更新后的密钥发送到密钥服务器上： +``` +$ gpg --send-key [fpr] + +``` + +下一篇文章中，我们将谈谈 Git 如何支持 PGP 的多级别集成。 + +通过来自 Linux 基金会和 edX 的免费课程 [“Linux 入门" ][8]学习更多 Linux 知识。 + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-5-moving-subkeys-hardware-device + +作者：[KONSTANTIN RYABITSEV][a] +译者：[qhwdw](https://github.com/qhwdw) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.linux.com/users/mricon +[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools +[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key +[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys +[4]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage +[5]:https://shop.nitrokey.com/shop/product/nitrokey-start-6 +[6]:https://shop.nitrokey.com/shop/product/nitrokey-pro-3 +[7]:https://www.yubico.com/product/yubikey-4-series/ +[8]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux diff --git a/translated/tech/20180321 Protecting Code Integrity with PGP - Part 6- Using PGP with Git.md b/translated/tech/20180321 Protecting Code Integrity with PGP - Part 6- Using PGP with Git.md new file mode 100644 index 0000000000..ba010bb0ec --- /dev/null +++ b/translated/tech/20180321 Protecting Code Integrity with PGP - Part 6- Using PGP with Git.md @@ -0,0 +1,318 @@ +保护代码完整性（六）：在 Git 上使用 PGP +====== + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/global-network.jpg?itok=h_hhZc36) +在本系列教程中，我们提供了一个使用 PGP 的实用指南，包括基本概念和工具、生成和保护你的密钥。如果你错过了前面的文章，你可以查看下面的链接。在这篇文章中，我们谈一谈在 Git 中如何集成 PGP、使用签名的标签，然后介绍签名提交，最后添加签名推送的支持。 + +[第一部分：基本概念和工具][1] + +[第二部分：生成你的主密钥][2] + +[第三部分：生成 PGP 子密钥][3] + +[第四部分：将主密钥移到离线存储中][4] + +[第五部分：将子密钥移到硬件设备中][5] + +Git 的核心特性之一就是它的去中心化本质 —— 一旦仓库克隆到你的本地系统，你就拥有了项目的完整历史，包括所有的标签、提交和分支。然而由于存在着成百上千的克隆仓库，如何才能验证你下载的仓库没有被恶意的第三方做过篡改？你可以从 GitHub 或一些貌似官方的位置来克隆它们，但是如果有些人故意欺骗了你怎么办？ + +或者在你参与的一些项目上发现了后门，而 "Author" 行显示是你干的，然而你很确定 [不是你干的][6]，会发生什么情况？ + +为解决上述问题，Git 添加了 PGP 集成。签名的标签通过确认它的内容与创建这个标签的开发者的工作站上的内容完全一致来证明仓库的完整性，而签名的提交几乎是不可能在不访问你的 PGP 密钥的情况下能够假冒你。 + +### 清单 + + * 了解签名的标签、提交、和推送（必要） + + * 配置 git 使用你的密钥（必要） + + * 学习如何签名标签和验证工作（必要） + + * 配置 git 总是签名注释的标签（推荐） + + * 学习如何签名提交和验证工作（必要） + + * 配置 git 总是签名提交（推荐） + + * 配置 gpg-agent 选项（必要） + + + + +### 考虑事项 + +Git 实现了 PGP 的多级集成，首先从签名标签开始，接着介绍签名提交，最后添加签名推送的支持。 + +#### 了解 Git 哈希 + +Git 是一个复杂的东西，为了你能够更好地掌握它如何集成 PGP，你需要了解什么是”哈希“。我们将它归纳为两种类型的哈希：树哈希和提交哈希。 + +##### 树哈希 + +每次你向仓库提交一个变更，对于仓库中的每个子目录，git 都会记录它里面所有对象的校验和哈希 —— 内容（blobs）、目录（trees）、文件名和许可等等。它只对每次提交中发生变更的树和内容做此操作，这样在只变更树的一小部分时就不必去重新计算整个树的校验和。 + +然后再计算和存储处于顶级的树的校验和，这样如果仓库的任何一部分发生变化，校验和将不可避免地发生变化。 + +##### 提交哈希 + +一旦创建了树哈希，git 将计算提交哈希，它将包含有关仓库和变更的下列信息： + + * 树哈希的校验和 + + * 变更前树哈希的校验和（父级） + + * 有关作者的信息（名字、email、创作时间） + + * 有关提交者的信息（名字、email、提交时间） + + * 提交信息 + + + + +##### 哈希函数 + +在写这篇文章时，虽然研究一种更强大的、抗碰撞的算法的工作正在进行，但 git 仍然使用的是 SHA1 哈希机制去计算校验和。注意，git 已经包含了碰撞防范程序，因此认为对 git 成功进行碰撞攻击仍然是不可行的。 + +#### 注释的标签和标签签名 + +在每个 Git 仓库中，标签允许开发者标记特定的提交。标签可以是 “轻量级的” —— 几乎只是一个特定提交上的指针，或者它们可以是 “注释的”，它成为 git 树中自己的项目。一个注释的标签对象包含所有下列的信息： + + * 成为标签的提交哈希的校验和 + + * 标签名字 + + * 关于打标签的人的信息（名字、email、打标签时间） + + * 标签信息 + + + + +一个 PGP 签名的标签是一个带有将所有这些条目封装进一个 PGP 签名的注释标签。当开发者签名他们的 git 标签时，他们实际上是向你保证了如下的信息： + + * 他们是谁（以及他们为什么应该被信任） + + * 他们在签名时的仓库状态是什么样： + + * 标签包含提交的哈希 + + * 提交哈希包含了顶级树的哈希 + + * 顶级哈希包含了所有文件、内容和子树的哈希 + * 它也包含有关作者的所有信息 + + * 包含变更发生时的精确时间 + + + + +当你克隆一个仓库并验证一个签名标签时，就是向你以密码方式保证仓库中的所有内容、包括所有它的历史，与开发者签名时在它的计算机上的仓库完全一致。 + +#### 签名的提交 + +签名的提交与签名的标签非常类似 —— 提交对象的内容是 PGP 签名过的，而不是标签对象的内容。一个提交签名也给你提供了开发者签名时，开发者树上的全部可验证信息。标签签名和提交 PGP 签名提供了有关仓库和它的完整历史的完全一致的安全保证。 + +#### 签名的推送 + +为了完整起见，在这里包含了签名的推送这一功能，因为在你使用这个功能之前，需要在接收推送的服务器上先启用它。正如我们在上面所说过的，PGP 签名一个 git 对象就是提供了开发者的 git 树当时的可验证信息，但不提供开发者对那个树意图相关的信息。 + +比如，你可以在你自己 fork 的 git 仓库的一个实验分支上尝试一个很酷的特性，为了评估它，你提交了你的工作，但是有人在你的代码中发现了一个恶意的 bug。由于你的提交是经过正确签名的，因此有人可能将包含有恶意 bug 的分支推入到 master 分支中，从而在生产系统中引入一个漏洞。由于提交是经过你的密钥正确签名的，所以一切看起来都是合理合法的，而当 bug 被发现时，你的声誉就会因此而受到影响。 + +在 `git push` 时，为了验证提交的意图而不仅仅是验证它的内容，添加了要求 PGP 推送签名的功能。 + +#### 配置 git 使用你的 PGP 密钥 + +如果在你的钥匙环上只有一个密钥，那么你就不需要再做额外的事了，因为它是你的默认密钥。 + +然而，如果你有多个密钥，那么你必须要告诉 git 去使用哪一个密钥。（[fpr] 是你的密钥的指纹）： +``` +$ git config --global user.signingKey [fpr] + +``` + +注意：如果你有一个不同的 gpg2 命令，那么你应该告诉 git 总是去使用它，而不是传统的版本 1 的 gpg： +``` +$ git config --global gpg.program gpg2 + +``` + +#### 如何使用签名标签 + +创建一个签名的标签，只要传递一个简单地 -s 开关给 tag 命令即可： +``` +$ git tag -s [tagname] + +``` + +我们建议始终对 git 标签签名，这样让其它的开发者确信他们使用的 git 仓库没有被恶意地修改过（比如，引入后门）： + +##### 如何验证签名的标签 + +验证一个签名的标签，只需要简单地使用 verify-tag 命令即可： +``` +$ git verify-tag [tagname] + +``` + +如果你要验证其他人的 git 标签，那么就需要你导入他的 PGP 公钥。请参考 “可信任的团队沟通” 一文中关于此主题的指导。 + +##### 在拉取时验证 + +如果你从项目仓库的其它 fork 中拉取一个标签，git 将自动验证签名，并在合并操作时显示结果： +``` +$ git pull [url] tags/sometag + +``` + +合并信息将包含类似下面的内容： +``` +Merge tag 'sometag' of [url] + +[Tag message] + +# gpg: Signature made [...] +# gpg: Good signature from [...] + +``` + +#### 配置 git 始终签名注释的标签 + +很可能的是，你正在创建一个带注释的标签，你应该去签名它。强制 git 始终签名带注释的标签，你可以设置一个全局配置选项： +``` +$ git config --global tag.forceSignAnnotated true + +``` + +或者，你始终记得每次都传递一个 -s 开关： +``` +$ git tag -asm "Tag message" tagname + +``` + +#### 如何使用签名提交 + +创建一个签名提交很容易，但是将它纳入到你的工作流中却很困难。许多项目使用签名提交作为一种 "Committed-by:” 的等价行，它记录了代码来源 —— 除了跟踪项目历史外，签名很少有人去验证。在某种意义上，签名的提交用于 ”篡改证据“，而不是 git 工作流的 ”篡改证明“。 + +为创建一个签名的提交，你只需要 `git commit` 命令传递一个 -S 标志即可（由于它与另一个标志冲突，所以改为大写的 -S）： +``` +$ git commit -S + +``` + +我们建议始终使用签名提交，并要求项目所有成员都这样做，这样其它人就可以验证它们（下面就讲到如何验证）。 + +##### 如何去验证签名的提交 + +验证签名的提交需要使用 verify-commit 命令： +``` +$ git verify-commit [hash] + +``` + +你也可以查看仓库日志，要求所有提交签名是被验证和显示的： +``` +$ git log --pretty=short --show-signature + +``` + +##### 在 git merge 时验证提交 + +如果项目的所有成员都签名了他们的提交，你可以在合并时强制进行签名检查（然后使用 -S 标志对合并操作本身进行签名）： +``` +$ git merge --verify-signatures -S merged-branch + +``` + +注意，如果有一个提交没有签名或验证失败，将导致合并操作失败。通常情况下，技术是最容易的部分 —— 而人的因素使得项目中很难采用严格的提交验证。 + +##### 如果你的项目在补丁管理上采用邮件列表 + +如果你的项目在提交和处理补丁时使用一个邮件列表，那么一般很少使用签名提交，因为通过那种方式发送时，签名信息将会丢失。对提交进行签名仍然是非常有用的，这样引用你托管在公开 git 树的其他人就能以它作为参考，但是上游项目接收你的补丁时，仍然不能直接使用 git 去验证它们。 + +尽管，你仍然可以签名包含补丁的电子邮件。 + +#### 配置 git 始终签名提交 + +你可以告诉 git 总是签名提交： +``` +git config --global commit.gpgSign true + +``` + +或者你每次都记得给 `git commit` 操作传递一个 -S 标志（包括 —amend）。 + +#### 配置 gpg-agent 选项 + +GnuPG agent 是一个守护工具，它能在你使用 gpg 命令时随时自动启动，并运行在后台来缓存私钥的密码。这种方式让你只需要解锁一次密钥就可以重复地使用它（如果你需要在一个自动脚本中签署一组 git 操作，而不需要重复输入密钥，这种方式就很方便）。 + +为了调整缓存中的密钥过期时间，你应该知道这两个选项： + + * default-cache-ttl（秒）：如果在 time-to-live 过期之前再次使用同一个密钥，这个倒计时将重置成另一个倒计时周期。缺省值是 600（10 分钟）。 + + * max-cache-ttl（秒）：自首次密钥输入以后，不论最近一次使用密钥是什么时间，只要最大值的 time-to-live 倒计时过期，你将被要求再次输入密码。它的缺省值是 30 分钟。 + + + + +如果你认为这些缺省值过短（或过长），你可以编辑 ~/.gnupg/gpg-agent.conf 文件去设置你自己的值： +``` +# set to 30 minutes for regular ttl, and 2 hours for max ttl +default-cache-ttl 1800 +max-cache-ttl 7200 + +``` + +##### 额外好处：与 ssh 一起使用 gpg-agent + +如果你创建了一个 [A]（验证）密钥，并将它移到了智能卡，你可以将它用到 ssh 上，为你的 ssh 会话添加一个双因子验证。为了与 agent 沟通你只需要告诉你的环境去使用正确的套接字文件即可。 + +首先，添加下列行到你的 ~/.gnupg/gpg-agent.conf 文件中： +``` +enable-ssh-support + +``` + +接着，添加下列行到你的 .bashrc 文件中： +``` +export SSH_AUTH_SOCK=$(gpgconf --list-dirs agent-ssh-socket) + +``` + +为了让改变生效，你需要 kill 掉正在运行的 gpg-agent 进程，并重新启动一个新的登入会话： +``` +$ killall gpg-agent +$ bash +$ ssh-add -L + +``` + +最后的命令将列出代表你的 PGP Auth 密钥的 SSH（注释应该会在结束的位置显示： cardno:XXXXXXXX，表示它来自智能卡）。 + +为了启用 ssh 的基于密钥的登入，只需要在你要登入的远程系统上添加 `ssh-add -L` 的输出到 ~/.ssh/authorized_keys 中。祝贺你，这将使你的 SSH 登入凭据更难以窃取。 + +作为一个福利，你可以从公共密钥服务器上下载其它人的基于 PGP 的 ssh 公钥，这样就可以赋予他登入 ssh 的权利： +``` +$ gpg --export-ssh-key [keyid] + +``` + +如果你有让开发人员通过 ssh 来访问 git 仓库的需要，这将让你非常方便。下一篇文章，我们将提供像保护你的密钥那样保护电子邮件帐户的小技巧。 + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-6-using-pgp-git + +作者：[KONSTANTIN RYABITSEV][a] +译者：[qhwdw](https://github.com/qhwdw) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.linux.com/users/mricon +[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools +[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key +[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys +[4]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage +[5]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-5-moving-subkeys-hardware-device +[6]:https://github.com/jayphelps/git-blame-someone-else diff --git a/translated/tech/20180326 Manage your workstation with Ansible- Automating configuration.md b/translated/tech/20180326 Manage your workstation with Ansible- Automating configuration.md new file mode 100644 index 0000000000..c464f4ea32 --- /dev/null +++ b/translated/tech/20180326 Manage your workstation with Ansible- Automating configuration.md @@ -0,0 +1,231 @@ +使用Ansible来管理你的工作站：配置自动化 +====== + +![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/robot_arm_artificial_ai.png?itok=8CUU3U_7) + +Ansible是一个令人惊讶的自动化的配置管理工具。主要应用在服务器和云部署上，但在工作站上的应用（无论是台式机还是笔记本）却得到了很少的关注，这就是本系列所要关注的。 + +在这个系列的第一部分，我会向你展示'ansible-pull'命令的基本用法，我们创建了一个安装了少量包的palybook.它本身是没有多大的用处的，但是它为后续的自动化做了准备。 + +在这篇文章中，所有的事件操作都是闭环的，而且在最后部分，我们将会有一个针对工作站自动配置的完整的工作解决方案。现在，我们将要设置Ansible的配置，这样未来将要做的改变将会自动的部署应用到我们的工作站上。现阶段，假设你已经完成了第一部分的工作。如果没有的话，当你完成的时候回到本文。你应该已经有一个包含第一篇文章中代码的Github库。我们将直接按照之前的方式创建。 + +首先，因为我们要做的不仅仅是安装包文件，所以我们要做一些重新的组织工作。现在，我们已经有一个名为'local.yml'并包含以下内容的playbook: +``` +- hosts: localhost + + become: true + + tasks: + + - name: Install packages + + apt: name={{item}} + + with_items: + + - htop + + - mc + + - tmux + +``` + +如果我们仅仅想实现一个任务那么上面的配置就足够了。随着向我们的配置中不断的添加内容，这个文件将会变的相当的庞大和杂乱。最好能够根据不同类型的配置将play文件分为独立的文件。为了达到这个要求，创建一个名为taskbook的文件，它和playbook很像但内容更加的流线型。让我们在Git库中为taskbook创建一个目录。 +``` +mkdir tasks + +``` + +在'local.yml'playbook中的代码使它很好过过渡到成为安装包文件的taskbook.让我们把这个文件移动到刚刚创建好并新命名的目录中。 + +``` +mv local.yml tasks/packages.yml + +``` +现在，我们编辑'packages.yml'文件将它进行大幅的瘦身，事实上，我们可以精简除了独立任务本身之外的所有内容。让我们把'packages.yml'编辑成如下的形式： +``` +- name: Install packages + + apt: name={{item}} + + with_items: + + - htop + + - mc + + - tmux + +``` + +正如你所看到的，它使用同样的语法，但我们去掉了对这个任务无用没有必要的所有内容。现在我们有了一个专门安装包文件的taskbook.然而我们仍然需要一个名为'local.yml'的文件，因为执行'ansible-pull'命令时仍然会去发现这个文件。所以我们将在我们库的根目录下（不是在'task'目录下）创建一个包含这些内容的全新文件： +``` +- hosts: localhost + + become: true + + pre_tasks: + + - name: update repositories + + apt: update_cache=yes + + changed_when: False + + + + tasks: + + - include: tasks/packages.yml + +``` + +这个新的'local.yml'扮演的是将要导入我们的taksbooks的主页的角色。我已经在这个文件中添加了一些你在这个系列中看不到的内容。首先，在这个文件的开头处，我添加了'pre——tasks',这个任务的作用是在其他所有任务运行之前先运行某个任务。在这种情况下，我们给Ansible的命令是让它去更新我们的分布存储库主页，下面的配置将执行这个任务要求： + +``` +apt: update_cache=yes + +``` +通常'apt'模块是用来安装包文件的，但我们也能够让它来更新库索引。这样做的目的是让我们的每个play在Ansible运行的时候能够以最新的索引工作。这将确保我们在使用一个老旧的索引安装一个包的时候不会出现问题。因为'apt'模块仅仅在Debian，Ubuntu和他们的衍生环境下工作。如果你运行的一个不同的环境，你期望在你的环境中使用一个特殊的模块而不是'apt'。如果你需要使用一个不同的模块请查看Ansible的相关文档。 + +下面这行值得以后解释： +``` +changed_when: False + +``` +在独立任务中的这行阻止了Ansible去报告play改变的结果即使是它本身在系统中导致的一个改变。在这中情况下，我们不会去在意库索引是否包含新的数据；它几乎总是会的，因为库总是在改变的。我们不会去在意'apt'库的改变，因为索引的改变是正常的过程。如果我们删除这行，我们将在过程保告的后面看到所有的变动，即使仅仅库的更新而已。最好能够去忽略这类的改变。 + +接下来是常规任务的阶段，我们将创建好的taskbook导入。我们每次添加另一个taskbook的时候，要添加下面这一行： +``` +tasks: + + - include: tasks/packages.yml + +``` + +如果你将要运行'ansible-pull'命令，他应该向上一篇文章中的那样做同样重要的事情。 不同的是我们已经提高了我们的组织并且能够更有效的扩展它。'ansible-pull'命令的语法，为了节省你到上一篇文章中去寻找，参考如下： +``` +sudo ansible-pull -U https://github.com//ansible.git + +``` +如果你还记得话，'ansible-pull'的命令拉取一个Git库并且应用了它所包含的配置。 + +既然我们的基础已经搭建好，我们现在可以扩展我们的Ansible并且添加功能。更特别的是，我们将添加配置来自动化的部署对工作站要做的改变。为了支撑这个要求，首先我们要创建一个特殊的账户来应用我们的Ansible配置。这个不是必要的，我们仍然能够在我们自己的用户下运行Ansible配置。但是使用一个隔离的用户能够将其隔离到不需要我们参与的在后台运行的一个系统进程中， + +我们可以使用常规的方式来创建这个用户，但是既然我们正在使用Ansible,我们应该尽量避开使用手动的改变。替代的是，我们将会创建一个taskbook来处理用户的创建任务。这个taskbook目前将会仅仅创建一个用户，但你可以在这个taskbook中添加额外的plays来创建更多的用户。我将这个用户命名为'ansible'，你可以按照自己的想法来命名（如果你做了这个改变要确保更新所有的变动）。让我们来创建一个名为'user.yml'的taskbook并且将以下代码写进去： + +``` +- name: create ansible user + + user: name=ansible uid=900 + +``` +下一步，我们需要编辑'local.yml'文件，将这个新的taskbook添加进去，像如下这样写： + +``` +- hosts: localhost + + become: true + + pre_tasks: + + - name: update repositories + + apt: update_cache=yes + + changed_when: False + + + + tasks: + + - include: tasks/users.yml + + - include: tasks/packages.yml + +``` +现在当我们运行'ansible-pull'命令的时候，一个名为'ansible'的用户将会在系统中被创建。注意我特地通过参数'UID'为这个用户声明了用户ID为900。这个不是必须的，但建议直接创建好UID。因为在1000以下的UID在登陆界面是不会显示的，这样是很棒的因为我们根本没有需要去使用'ansibe'账户来登陆我们的桌面。UID 900是固定的；它应该是在1000以下没有被使用的任何一个数值。你可以使用以下命令在系统中去验证UID 900是否已经被使用了： + +``` +cat /etc/passwd |grep 900 + +``` +然而，你使用这个UID应该不会遇到什么问题，因为迄今为止在我使用的任何发行版中我还没遇到过它是被默认使用的。 + +现在，我们已经拥有了一个名为'ansible'的账户，它将会在之后的自动化配置中使用。接下来，我们可以创建实际的定时作业来自动操作它。而不是将其放置到我们刚刚创建的'users.yml'文件中，我们应该将其分开放到它自己的文件中。在任务目录中创建一个名为'cron.yml'的taskbook并且将以下的代买写进去： +``` +- name: install cron job (ansible-pull) + + cron: user="ansible" name="ansible provision" minute="*/10" job="/usr/bin/ansible-pull -o -U https://github.com//ansible.git > /dev/null" + +``` +定时模块的语法几乎是不需加以说明的。通过这个play,我们创建了一个通过用户'ansible'运行的定时作业。这个作业将每隔10分钟执行一次，下面是它将要执行的命令： + +``` +/usr/bin/ansible-pull -o -U https://github.com//ansible.git > /dev/null + +``` +同样，我们也可以添加想要我们的所有工作站部署的额外定时作业到这个文件中。我们只需要在新的定时作业中添加额外的palys即可。然而，仅仅是添加一个定时的taskbook是不够的，我们还需要将它添加到'local.yml'文件中以便它能够被调用。将下面的一行添加到末尾： +``` +- include: tasks/cron.yml + +``` +现在当'ansible-pull'命令执行的时候，它将会以通过用户'ansible'每个十分钟设置一个新的定时作业。但是，每个十分钟运行一个Ansible作业并不是一个好的方式因为这个将消耗很多的CPU资源。每隔十分钟来运行对于Ansible来说是毫无意义的除非欧文已经在Git库中改变一些东西。 + +然而，我们已经解决了这个问题。注意到我在定时作业中的命令'ansible-pill'添加的我们之前从未用到过的参数'-o'.这个参数告诉Ansible只有在从上次'ansible-pull'被调用以后库有了变化后才会运行。如果库没有任何变化，他将不会做任何事情。通过这个方法，你将不会无端的浪费CPU资源。当然，一些CPU资源将会在下来存储库的时候被使用，但不会像再一次应用整个配置的时候使用的那么多。当'ansible-pull'执行的时候，它将会遍历在playbooks和taskbooks中的所有任务，但至少它不会毫无目的的运行。 + +尽管我们已经添加了所有必须的配置要素来自动化'ansible-pull',它任然还不能正常的工作。'ansible-pull'命令需要sudo的权限来运行，这将允许它执行系统级的命令。然而我们创建的用户'ansible'并没有被设置为以'sudo'的权限来执行命令，因此当定时作业触发的时候，执行将会失败。通常沃恩可以使用命令'visudo'来手动的去设置用户'ansible'的拥有这个权限。然而我们现在应该以Ansible的方式来操作，而且这将会是一个向你展示'copy'模块是如何工作的机会。'copy'模块允许你从库复制一个文件到文件系统的任何位置。在这个案列中，我们将会复制'sudo'的一个配置文件到'/etc/sudoers.d/'以便用户'ansible'能够以管理员的权限执行任务。 + +打开'users.yml',将下面的play添加到文件末尾。 + +``` +- name: copy sudoers_ansible + + copy: src=files/sudoers_ansible dest=/etc/sudoers.d/ansible owner=root group=root mode=0440 + +``` +'copy'模块，正如我们看到的，从库复制一个文件到其他任何位置。在这个过程中，我们正在抓取一个名为'sudoers_ansible'(我们将在后续创建)的文件并将它复制到拥有者为'root'的'/etc/sudoers/ansible'中。 + +接下来，我们需要创建我们将要复制的文件。在你的库的根目录下，创建一个名为'files'的目录： + +``` +mkdir files + +``` +然后，在我们刚刚创建的'files'目录里，创建包含以下内容的名为'sudoers_ansible'的文件： +``` +ansible ALL=(ALL) NOPASSWD: ALL + +``` +在'/etc/sudoer.d'目录里创建一个文件，就像我们正在这样做的，允许我们为一个特殊的用户配置'sudo'权限。现在我们正在通过'sudo'允许用户'ansible'不需要密码拥有完全控制权限。这将允许'ansible-pull'以后台任务的形式运行而不需要手动去运行。 + +现在，你可以通过再次运行'ansible-pull'来拉取最新的变动： +``` +sudo ansible-pull -U https://github.com//ansible.git + +``` +从这个节点开始，'ansible-pull'的定时作业将会在后台每隔十分钟运行一次来检查你的库是否有变化，如果它发现有变化，将会运行你的palybook并且应用你的taskbooks. + +所以现在我们有了一个完整的工作方案。当你第一次设置一台新的笔记本或者台式机的时候，你要去手动的运行'ansible-pull'命令，但仅仅是在第一次的时候。从第一次之后，用户'ansible'将会在后台接手后续的运行任务。当你想对你的机器做变动的时候，你只需要简单的去拉取你的Git库来做变动，然后将这些变化回传到库中。接着，当定时作业下次在每台机器上运行的时候，它将会拉取变动的部分并应用它们。你现在只需要做一次变动，你的所有工作站将会跟着一起变动。这方法尽管有一点不方便，通常，你会有一个你的机器列表的文件和包含不同机器的规则。不管怎样，'ansible-pull'的方法，就像在文章中描述的，是管理工作站配置的非常有效的方法。 + +我已经在我的[Github repository]中更新了这篇文章中的代码，所以你可以随时去浏览来再一次检查你的语法。同时我将前一篇文章中的代码移到了它自己的目录中。 + +在第三部分，我们将通过介绍使用Ansible来配置GNOME桌面设置来结束这个系列。我将会告诉你如何设置你的墙纸和锁屏壁纸，应用一个桌面主题以及更多的东西。 + +同时，到了布置一些作业的时候了，大多数人有我们使用的各种应用的配置文件。可能是Bash,Vim或者其他你使用的工具的配置文件。现在你可以尝试通过我们在使用的Ansible库来自动复制这些配置到你的机器中。在这篇文章中，我已将想你展示了如何去复制文件，所以去尝试以下看看你是都已经能应用这些知识。 + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/18/3/manage-your-workstation-configuration-ansible-part-2 + +作者：[Jay LaCroix][a] +译者：[FelixYFZ](https://github.com/FelixYFZ) +校对：[校对者ID](https://github.com/校对者ID) +选题：[lujun9972](https://github.com/lujun9972) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://opensource.com/users/jlacroix +[1]:https://opensource.com/article/18/3/manage-workstation-ansible +[2]:https://github.com/jlacroix82/ansible_article.git diff --git a/translated/tech/20180327 Protecting Code Integrity with PGP - Part 7- Protecting Online Accounts.md b/translated/tech/20180327 Protecting Code Integrity with PGP - Part 7- Protecting Online Accounts.md new file mode 100644 index 0000000000..4cf1f321c1 --- /dev/null +++ b/translated/tech/20180327 Protecting Code Integrity with PGP - Part 7- Protecting Online Accounts.md @@ -0,0 +1,145 @@ +保护代码完整性（七）：保护在线帐户 +====== + +![](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/online-pgp.jpg?itok=BWc_Bk6q) +到目前为止，本系列教程已经提供了 PGP 的实用指南，包括基本概念和工具、生成和保护你的密钥的步骤。如果你错过了前面的文章，可以通过下面的链接查看。在本系列的最后一篇文章中，我们将为你保护在线帐户提供一个额外的指南，保护在线帐户是当今非常重要的一件事情。 + +[第一部分：基本概念和工具][1] + +[第二部分：生成你的主密钥][2] + +[第三部分：生成 PGP 子密钥][3] + +[第四部分：将主密钥移到离线存储中][4] + +[第五部分：将子密钥移到硬件设备中][5] + +[第六部分：在 Git 中使用 PGP][6] + +### 清单 + + * 取得一个具备 U2F 功能的设备（必要） + + * 为你的在线帐户启用双因子认证（必要） + + * GitHub/GitLab + + * Google + + * 社交媒体 + + * 使用 U2F 作为主验证机制，使用 TOTP 作为备选（必要） + + + + +#### 考虑事项 + +你可能注意到，很多在线开发者身份是捆绑了你的 email 地址。如果有人能够访问你的邮箱，他们就能够去做一些对你会产生危害的事情，进而会损害你作为自由软件开发者的声誉。应该像保护你的 PGP 密钥那样保护你的 email 地址。 + +##### 使用 Fido U2F 的双因子认证 + +[双因子认证][7] 是一种提升帐户安全性的机制，它除了要求用户名和密码之外，还要求一个物理令牌。它的目标是即便在有人窃取了你的密码（通过按键记录器、肩窥攻击、或其它方式）的情况下，仍然能确保你的帐户安全，他们在没有得到你的一个专用的物理设备（“必备”的那个因子）的情况下，始终不能获取你的帐户。 + +广为人知的双因子认证机制有： + + * 基于 SMS 的验证 + + * 借助智能手机应用的基于时间的一次性令牌（TOTP），比如 "Google Authenticator" 或类似解决方案 + + * 支持 Fido U2F 的硬件令牌 + + + + +基于 SMS 的验证很容易配置，但是它有如下的缺点：它在没有手机信号的地方无法使用（比如，建筑物的地下室），并且如果攻击者能够阻断或转向 SMS 信息，这种方式可能就会失败，比如通过克隆你的 SIM 卡。 + +基于 TOTP 的多因子认证提供了比 SMS 更好的安全保护，但它也有一些重要的缺点（在你能够找到一个合适的令牌之前，你只能在智能手机中添加那么多令牌）。此外，还不能避免一个事实，那就是你的密钥最终还是保存在你的智能手机中 —— 它是一个复杂的、全球连接的设备，它有可能还没有及时从制造商那儿收到安全补丁。 + +更重要的是，不论是使用 TOTP 还是 SMS 的方法保护你免受诱骗攻击 —— 如果诱骗攻击者能够窃取你的帐户密码和双因子令牌，他们就可以在合法的站点上使用它们，访问你的帐户。 + +[Fido U2F][8] 是一个按标准开发的专用设备，它能够提供双因子认证机制来对付诱骗攻击。U2F 协议在 USB 令牌中保存每个站点的的唯一密钥，如果你在任何合法站点以外的地方尝试使用它，它将阻止你，以防范偶然让攻击者获得你的密码和一次性令牌。 + +Chrome 和 Firefox 都支持 U2F 双因子认证，希望其它浏览器也能够提供对 U2F 的支持。 + +##### 获得一个支持 Fido U2F 功能的令牌 + +支持 U2F 的硬件令牌的 [可选目标很多][9]，但如果你已经订购了一个支持智能卡的物理设备，那么你最好的选择就是 Yubikey 4，它两者都支持。 + +##### 启用你的在线帐户的双因子认证 + +你要确定你想去启用的选项，你的 email 提供商已经使用了（特别是 Google，它对 U2F 的支持非常好）。其它的站点这个功能应该是启用了： + + * GitHub：当你上传你的 PGP 公钥时，你应该要想到，如果其他人能够获得访问你的帐户，他们可以用他们自己的 PGP 公钥替换掉你的 PGP 公钥。如果在 GitHub 上发布代码，你应该使用 U2F 认证来保护你的帐户安全。 + + * GitLab：理由同上 + + * Google：如果你有 google 帐户，你就惊奇地发现，许多帐户都允许以 Google 帐户来代替站点专用的认证来登入它们。 + + * Facebook：理由同上，许多在线站点都提供一个选择让你以 Facebook 的帐户来认证。即便你不使用 Facebook 也应该使用双因子认证来保护你的 Facebook 帐户。 + + * 你认为必要的其它站点。查看 [dongleauth.info][10] 去找找灵感。 + + + + +##### 如有可能，配置 TOTP 作为备选 + +许多站点都允许你配置多个双因子认证机制，推荐的设置是： + + * U2F 令牌作为主认证机制 + + * TOTP 手机 app 作为辅助认证机制 + + + + +通过这种方式，即便你丢失了你的 U2F 令牌，你仍然能够重新获取对你的帐户的访问。或者，你可以注册多个 U2F 令牌（即：你可以用一个便宜的令牌仅用它做 U2F，并且将它用作备份）。 + +### 延伸阅读 + +到目前为止，你已经完成了下列的重要任务： + + 1. 创建你的开发者身份并使用 PGP 加密来保护它。 + + 2. 通过将你的主密钥移到一个离线存储中并将子密钥移到一个外置硬件设备中的方式来配置你的环境，让窃取你的身份变得极为困难。 + + 3. 配置你的 Git 环境去确保任何使用你项目的人都能够验证仓库的完整性和它的整个历史。 + + 4. 使用双因子认证强化你的在线帐户。 + + + + +在安全保护方面，你已经做的很好了，但是你还应该去阅读以下的主题： + + * 如何去强化你的团队沟通（在这个仓库中查看相关文档）。你的项目开发和治理决策的要求应该和保护提交代码那样去保护，如果不这样做，应该确保你的团队沟通是可信任的，并且所有决策的完整性是可验证的。 + + * 如何去强化你的工作站的安全（在这个仓库中查看相关文档）。你的目标是最小化可能导致项目代码被污染的危险或你的开发者身份被窃的行为。 + + * 如何写出安全的代码（查看相关编程语言和你项目所使用的库的各种文档）。即便引入它的提交代码上有一个 PGP 签名，糟糕的、不安全的代码仍然是糟糕的、不安全的代码！ + + + +-------------------------------------------------------------------------------- + +via: https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-7-protecting-online-accounts + +作者：[Konstantin Ryabitsev][a] +译者：[qhwdw](https://github.com/qhwdw) +校对：[校对者ID](https://github.com/校对者ID) +选题：[lujun9972](https://github.com/lujun9972) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.linux.com/users/mricon +[1]:https://www.linux.com/blog/learn/2018/2/protecting-code-integrity-pgp-part-1-basic-pgp-concepts-and-tools +[2]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-2-generating-and-protecting-your-master-pgp-key +[3]:https://www.linux.com/blog/learn/pgp/2018/2/protecting-code-integrity-pgp-part-3-generating-pgp-subkeys +[4]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-4-moving-your-master-key-offline-storage +[5]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-5-moving-subkeys-hardware-device +[6]:https://www.linux.com/blog/learn/pgp/2018/3/protecting-code-integrity-pgp-part-6-using-pgp-git +[7]:https://en.wikipedia.org/wiki/Multi-factor_authentication +[8]:https://en.wikipedia.org/wiki/Universal_2nd_Factor +[9]:http://www.dongleauth.info/dongles/ +[10]:http://www.dongleauth.info/ diff --git a/translated/tech/20180331 Emacs -4- Automated emails to org-mode and org-mode syncing.md b/translated/tech/20180331 Emacs -4- Automated emails to org-mode and org-mode syncing.md deleted file mode 100644 index 976979192f..0000000000 --- a/translated/tech/20180331 Emacs -4- Automated emails to org-mode and org-mode syncing.md +++ /dev/null @@ -1,71 +0,0 @@ -Emacs #4：使用org-mode自动管理邮件及同步文档 -====== -这是 [Emacs 和 org-mode 系类][4]的第四篇。 - -至今为止，你已经见识到了 org-mode 的强大和高效，如果你像我一样，你可能会想： - -“我真的很想让它在我所有的设备上同步。” - -或者是说： - -“我能在 org-mode 中转发邮件吗？” - -答案当然是肯定的，因为这就是 Emacs。 - -### 同步 - -由于 org-mode 只使用文本文件，所以使用任意工具都可以很容易地实现同步。我使用的是 git 的 git-remote-gcrypt。由于 git-remote-gcrypt 的一些限制，每台机器都倾向于推到自己的分支，并使用命令来控制。每台机子都会先合并其他所有的 branch 然后再将合并后的结果 push 到 master 上。cron 作业可以实现将机器上的 branch push 上去，而 elisp 会协调这一切--确保在同步之前保存缓冲区，在同步之后从磁盘刷新缓冲区，等等。 - -这篇文章的代码有点多，所以我将把它链接到 github 上，而不是写在这里。 - - -我有一个用来存放我所有的 org-stuff 的目录 $HOME/org，在 ~/org 目录下有个 [Makefile][2] 文件来处理同步。该文件定义了一下目标： - * push： 添加，提交和 push 到以主机命名的 branch 上 - * fetch： 一个简单的 git fetch - * sync： 添加，提交和 pull 远程的修改，合并并将其 push 到以主机命名的 branch 和 master 上（假设合并成功） - - -现在，在我的用户 crontab 中有这个： -``` -*/15 * * * * make -C $HOME/org push fetch 2>&1 | logger --tag 'orgsync' - -``` -[accompanying elisp code][3] 定义了一个快捷键（C-c s）来调用同步。多亏了 cronjob，只要文件被保存 -- 即使我没有在另一个 boxen 上同步 -- 它们也会被 pull 进来。 - -我发现这个设置非常好用。 - -### 用 org-mode 发邮件 - -在继续下去之前，首先要问自己一下：你真的需要它吗？ 我用的是带有 [mu4e][4] 的 org-mode，而且它集成的也很好；任何组织任务都可以通过 message-id 链接到电子邮件，这很理想 -- 它可以让一个人做一些事情，比如提醒他在一周内回复一条消息。 - -然而，org 不仅仅只有提醒。它还是一个知识库、创作系统等，但是并不是我所有的邮件客户端都使用 mu4e。(注意:像 MobileOrg 是存在于移动设备中)。我并没有像我想的那样经常使用它，但是它有它的用途，所以我认为我也应该在这里记录它。 - -现在我不仅想处理纯文本电子邮件。我希望能够处理附件、HTML 邮件等。这听起来很快就有问题了 -- 但是通过使用 ripmime 和 pandoc 这样的工具，情况还不错。 - -第一步就是要用某些方法将获取到的邮件放入指定的文件夹下。扩展名，特殊用户等。然后我用 [fetchmail configuration][5] 来将它 pull 下来并运行我自己的 [insorgmail][6] 脚本。 - -这个脚本就是处理所有有趣的部分了。它从 ripmime 开始处理消息，用 pandoc 将HTML 的部分转换为 org 格式。 org 的层次结构是用来尽可能最好地表示 email 的结构。使用HTML和其他工具时，email 可能会变得相当复杂，但我发现这对于我来说是可以接受的。 - -### 下一篇 - -我最后一篇关于 org-mode 的文章将讨论如何使用它来编写文档和准备幻灯片 -- 我发现自己对 org-mode 的使用非常满意，但这需要一些调整。 - - - --------------------------------------------------------------------------------- - -via: http://changelog.complete.org/archives/9898-emacs-4-automated-emails-to-org-mode-and-org-mode-syncing - -作者：[John Goerzen][a] -译者：[oneforalone](https://github.com/oneforalone) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:http://changelog.complete.org/ -[1]:https://changelog.complete.org/archives/tag/emacs2018 -[2]:https://github.com/jgoerzen/public-snippets/blob/master/emacs/org-tools/Makefile -[3]:https://github.com/jgoerzen/public-snippets/blob/master/emacs/org-tools/emacs-config.org -[4]:https://www.emacswiki.org/emacs/mu4e -[5]:https://github.com/jgoerzen/public-snippets/blob/master/emacs/org-tools/fetchmailrc.orgmail -[6]:https://github.com/jgoerzen/public-snippets/blob/master/emacs/org-tools/insorgmail diff --git a/translated/tech/20180807 5 reasons the i3 window manager makes Linux better.md b/translated/tech/20180807 5 reasons the i3 window manager makes Linux better.md deleted file mode 100644 index 428665c170..0000000000 --- a/translated/tech/20180807 5 reasons the i3 window manager makes Linux better.md +++ /dev/null @@ -1,109 +0,0 @@ -i3窗口管理器让Linux更好的五个原因 -====== - -![](https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/cloud-windows.png?itok=jd5sBNQH) - -Linux（和一般的开源软件） 最美好的一点是在不同的替代方案中进行选择的自由，以满足我们的需求。 - -我使用 Linux 已经很长时间了，但我从来没有对可用的桌面环境完全满意。直到去年 [Xfce][1] 是我认为在功能和性能之间的一个接近优秀的妥协。然后我发现 [i3][2] 一个惊人的软件改变了我的生活 - -I3 是一个平铺窗口管理器。窗口管理器的目标是控制窗口系统中窗口的外观和位置。窗口管理器通常用作功能齐全的桌面环境 (如 GONME 或 Xfce ) 的一部分, 但也有一些可以用作独立的应用程序。 - -平铺式窗口管理器会自动排列窗口, 以不重叠的方式占据整个屏幕。其他流行的平铺式窗口管理器包括 [wmii][3] 和 [xmonad][4] 。 - -![i3 tiled window manager screenshot][6] - -带有三个的 i3 屏幕截图 - -以下是我使用 i3 窗口管理器的五个首要原因，并推荐它以获得更好的 Linux 桌面体验。 - -### 1\.简化的艺术 - -I3 速度很快。它既不冗杂, 也不花哨。它的设计简单而高效。作为开发人员, 我重视这些功能， 因为我可以使用额外的功能为我最喜欢的开发工具助力， 或者使用容器或虚拟机在本地测试内容。 - -此外， I3 是一个窗口管理器，与功能齐全的桌面环境不同，它并不规定您应该使用的应用程序。您是否想使用 Xfce 的 Thunar 作为文件管理器？GNOME 的 gedit 去编辑文本? I3 并不在乎。选择对您的工作流最有意义的工具，I3 将以相同的方式管理它们。 - -### 2\. 屏幕实际使用面积 - -作为平铺式窗口管理器, I3 将自动 "平铺" 或以不重叠的方式定位窗口, 类似于在墙上放置瓷砖。因为您不需要担心窗口定位, i3 一般会更好地利用您的屏幕空间。它还可以让您更快地找到您需要的东西。 - -对于这种情况有很多有用的例子。例如, 系统管理员可以打开多个？来同时监视或在不同的远程系统上工作;开发人员可以使用他们最喜欢的 IDE 或编辑器和几个？来测试他们的程序。 - -此外, i3 具有灵活性。如果您需要为特定窗口提供更多空间, 请启用全屏模式或切换到其他布局, 如堆叠或选项卡式（标签式）。 - -### 3\. 键盘驱动的工作流程 - -i3 广泛使用键盘快捷键来控制环境的不同方面。其中包括打开？和其他程序、调整大小和定位窗口、更改布局, 甚至退出 i3。当您开始使用 i3 时, 您需要记住其中的一些快捷方式来绕行，随着时间的推移，您会使用更多的快捷方式。 - -主要好处是, 您不需要经常用键盘和鼠标切换上下文。通过练习, 意味着您将提高工作流程的速度和效率。 - -例如， 要打开新的？，请按 `+` .由于窗口是自动定位的, 您可以立即开始键入命令。结合一个很好的？驱动的文本编辑器 (如 Vim) 和一个以键盘为焦点的浏览器，形成一个完全由键盘驱动的工作流程。 - -在 i3 中, 您可以为所有内容定义快捷方式。下面是一些示例: - - * 打开？ - * 打开浏览器 - * 更改布局 - * 调整窗口大小 - * 控制音乐播放器 - * 切换工作区 - -现在我已经习惯了这个工作形式，我已无法回到了常规的桌面环境。 - -### 4\. 灵活 - -i3 力求最小化，很少使用系统资源， 但这并不意味着它不可能漂亮。i3 具有灵活性, 可通过多种方式进行自定义， 以改善视觉体验。因为 i3 是一个窗口管理器, 所以它不提供启用自定义的工具，而是提供启用自定义的工具。您需要外部工具来实现这一点。一些例子: - - * 用 `feh` 定义桌面的背景图片。 - * 使用复合器管理器, 如`compton`以启用窗口淡入淡出和透明度等效果。 - * 用 `dmenu` 或 `rofi`以启用可从键盘快捷方式启动的可自定义菜单。 - * 用 `dunst` 用于桌面通知。 - - - -i3 是完全可配置的，您可以通过更新默认配置文件来控制它的各个方面。从更改所有键盘快捷键，到重新定义工作区的名称，再到修改状态栏，您都可以使 i3 以任何最适合您需要的方式运行。 - -![i3 with rofi menu and dunst desktop notifications][8] - -i3 与 `rofi` 菜单和 `dunst` 桌面通知。 - -最后, 对于更高级的用户， i3 提供了完整的进程间通信([IPC][9]) 界面， 允许您使用您最喜爱的语言来开发脚本或程序，以实现更多的自定义选项。 - -### 5\. 工作空间 - -在 i3 中, 工作区是对窗口进行分组的一种简单方法。您可以根据您的工作流以不同的方式对它们进行分组。例如, 您可以将浏览器放在一个工作区上, ？命令行放在另一个工作区上, 将电子邮件客户端放在第三个工作区上, 等等。您甚至可以更改 i3 的配置, 以便始终将特定应用程序分配给它们自己的工作区。 - -切换工作区既快速又简单。像 i3 中的往常一样，使用键盘快捷方式执行此操作。按 `+num` 切换到工作区 `num` 。如果您养成了始终将应用程序组的窗口分配到同一工作区的习惯，则可以在它们之间快速切换，这使得工作区成为非常有用的功能。 - -此外，还可以使用工作区来控制多监视器的设置，其中每个监视器都可以获得初始工作区。如果切换到该工作区, 则切换到该监视器，而无需让手离开键盘。 - -最后，i3 中还有另一种特殊类型的工作空间: the scratchpad（便笺簿）。它是一个不可见的工作区，通过按快捷方式显示在其他工作区的中间。这是一种方便的方式来访问您经常使用的窗口或程序，如电子邮件客户端或音乐播放器。 - -### 尝试一下吧 - -如果您重视简单性和效率， 并且不抵触使用键盘, i3 就是您的窗口管理器。有人说是为高级用户准备的，但情况不一定如此。你需要学习一些基本的快捷方式来度过开始的阶段，不久就会越来越自然并且不假思索地使用它们。 - -这篇文章只是触及了 i3 表面能做的事情。欲了解更多详情, 请咨询 [i3's documentation][10]. - --------------------------------------------------------------------------------- - -via: https://opensource.com/article/18/8/i3-tiling-window-manager - -作者：[Ricardo Gerardi][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[lixinyuxx](https://github.com/lixinyuxx) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]:https://opensource.com/users/rgerardi -[1]:https://xfce.org/ -[2]:https://i3wm.org/ -[3]:https://code.google.com/archive/p/wmii/ -[4]:https://xmonad.org/ -[5]:/file/406476 -[6]:https://opensource.com/sites/default/files/uploads/i3_screenshot.png "i3 tiled window manager screenshot" -[7]:/file/405161 -[8]:https://opensource.com/sites/default/files/uploads/rofi_dunst.png "i3 with rofi menu and dunst desktop notifications" -[9]:https://i3wm.org/docs/ipc.html -[10]:https://i3wm.org/docs/userguide.html diff --git a/translated/tech/20180907 6.828 lab tools guide.md b/translated/tech/20180907 6.828 lab tools guide.md deleted file mode 100644 index 1396289ad1..0000000000 --- a/translated/tech/20180907 6.828 lab tools guide.md +++ /dev/null @@ -1,200 +0,0 @@ -6.828 实验工具指南 -====== -### 6.828 实验工具指南 - -熟悉你的环境对高效率的开发和调试来说是至关重要的。本文将为你简单概述一下 JOS 环境和非常有用的 GDB 和 QEMU 命令。话虽如此，但你仍然需要去阅读 GDB 和 QEMU 手册，来理解这些强大的工具如何使用。 - -#### 调试小贴士 - -##### 内核 - -GDB 是你的朋友。使用 `qemu-gdb target`(或它的变体 `qemu-gdb-nox`）使 QEMU 等待 GDB 去绑定。下面在调试内核时用到的一些命令，可以去查看 GDB 的资料。 - -如果你遭遇意外的中断、异常、或三重故障，你可以使用 `-d` 参数要求 QEMU 去产生一个详细的中断日志。 - -调试虚拟内存问题时，尝试 QEMU 监视命令 `info mem`（提供内存高级概述）或 `info pg`（提供更多细节内容）。注意，这些命令仅显示**当前**页表。 - -（在实验 4 以后）去调试多个 CPU 时，使用 GDB 的线程相关命令，比如 `thread` 和 `info threads`。 - -##### 用户环境（在实验 3 以后） - -GDB 也可以去调试用户环境，但是有些事情需要注意，因为 GDB 无法区分开多个用户环境或用户环境与内核环境。 - -你可以使用 `make run-name`（或编辑 `kern/init.c` 目录）来指定 JOS 启动的用户环境，为使 QEMU 等待 GDB 去绑定，使用 `run-name-gdb` 的变体。 - -你可以符号化调试用户代码，就像调试内核代码一样，但是你要告诉 GDB，哪个符号表用到符号文件命令上，因为它一次仅能够使用一个符号表。提供的 `.gdbinit` 用于加载内核符号表 `obj/kern/kernel`。对于一个用户环境，这个符号表在它的 ELF 二进制文件中，因此你可以使用 `symbol-file obj/user/name` 去加载它。不要从任何 `.o` 文件中加载符号，因为它们不会被链接器迁移进去（库是静态链接进 JOS 用户二进制文件中的，因此这些符号已经包含在每个用户二进制文件中了）。确保你得到了正确的用户二进制文件；在不同的二直制文件中，库函数被链接为不同的 EIP，而 GDB 并不知道更多的内容！ - -（在实验 4 以后）因为 GDB 绑定了整个虚拟机，所以它可以将时钟中断看作为一种控制转移。这使得从底层上不可能实现步进用户代码，因为一个时钟中断无形中保证了片刻之后虚拟机可以再次运行。因此可以使用 `stepi` 命令，因为它阻止了中断，但它仅可以步进一个汇编指令。断点一般来说可以正常工作，但要注意，因为你可能在不同的环境（完全不同的一个二进制文件）上遇到同一个 EIP。 - -#### 参考 - -##### JOS makefile - -JOS 的 GNUmakefile 包含了在各种方式中运行的 JOS 的许多假目标。所有这些目标都配置 QEMU 去监听 GDB 连接（`*-gdb` 目标也等待这个连接）。要在运行中的 QEMU 上启动它，只需要在你的实验目录中简单地运行 `gdb ` 即可。我们提供了一个 `.gdbinit` 文件，它可以在 QEMU 中自动指向到 GDB、加载内核符号文件、以及在 16 位和 32 位模式之间切换。退出 GDB 将关闭 QEMU。 - - * `make qemu` - 在一个新窗口中构建所有的东西并使用 VGA 控制台和你的终端中的串行控制台启动 QEMU。想退出时，既可以关闭 VGA 窗口，也可以在你的终端中按 `Ctrl-c` 或 `Ctrl-a x`。 - * `make qemu-nox` - 和 `make qemu` 一样，但仅使用串行控制台来运行。想退出时，按下 `Ctrl-a x`。这种方式在通过 SSH 拨号连接到 Athena 上时非常有用，因为 VGA 窗口会占用许多带宽。 - * `make qemu-gdb` - 和 `make qemu` 一样，但它与任意时间被动接受 GDB 不同，而是暂停第一个机器指令并等待一个 GDB 连接。 - * `make qemu-nox-gdb` - 它是 `qemu-nox` 和 `qemu-gdb` 目标的组合。 - * `make run-nam` - （在实验 3 以后）运行用户程序 _name_。例如，`make run-hello` 运行 `user/hello.c`。 - * `make run-name-nox`,`run-name-gdb`, `run-name-gdb-nox` - （在实验 3 以后）与 `qemu` 目标变量对应的 `run-name` 的变体。 - - - -makefile 也接受几个非常有用的变量： - - * `make V=1 …` -详细模式。输出正在运行的每个命令，包括参数。 - * `make V=1 grade` -在评级测试失败后停止，并将 QEMU 的输出放入 `jos.out` 文件中以备检查。 - * `make QEMUEXTRA=' _args_ ' …` -指定传递给 QEMU 的额外参数。 - - - -##### JOS obj/ - -在构建 JOS 时，makefile 也产生一些额外的输出文件，这些文件在调试时非常有用： - - * `obj/boot/boot.asm`、`obj/kern/kernel.asm`、`obj/user/hello.asm`、等等。 -引导加载器、内核、和用户程序的汇编代码列表。 - * `obj/kern/kernel.sym`、`obj/user/hello.sym`、等等。 -内核和用户程序的符号表。 - * `obj/boot/boot.out`、`obj/kern/kernel`、`obj/user/hello`、等等。 -内核和用户程序链接的 ELF 镜像。它们包含了 GDB 用到的符号信息。 - - - -##### GDB - -完整的 GDB 命令指南请查看 [GDB 手册][1]。下面是一些在 6.828 课程中非常有用的命令，它们中的一些在操作系统开发之外的领域几乎用不到。 - - * `Ctrl-c` -在当前指令处停止机器并打断进入到 GDB。如果 QEMU 有多个虚拟的 CPU，所有的 CPU 都会停止。 - * `c`（或 `continue`） -继续运行，直到下一个断点或 `Ctrl-c`。 - * `si`（或 `stepi`） -运行一个机器指令。 - * `b function` 或 `b file:line`（或 `breakpoint`） -在给定的函数或行上设置一个断点。 - * `b * addr`（或 `breakpoint`） -在 EIP 的 addr 处设置一个断点。 - * `set print pretty` -启用数组和结构的美化输出。 - * `info registers` -输出通用寄存器 `eip`、`eflags`、和段选择器。更多更全的机器寄存器状态转储，查看 QEMU 自己的 `info registers` 命令。 - * `x/ N x addr` -以十六进制显示虚拟地址 addr 处开始的 N 个词的转储。如果 N 省略，默认为 1。addr 可以是任何表达式。 - * `x/ N i addr` -显示从 addr 处开始的 N 个汇编指令。使用 `$eip` 作为 addr 将显示当前指令指针寄存器中的指令。 - * `symbol-file file` -（在实验 3 以后）切换到符号文件 file 上。当 GDB 绑定到 QEMU 后，它并不是虚拟机中进程边界内的一部分，因此我们要去告诉它去使用哪个符号。默认情况下，我们配置 GDB 去使用内核符号文件 `obj/kern/kernel`。如果机器正在运行用户代码，比如是 `hello.c`，你就需要使用 `symbol-file obj/user/hello` 去切换到 hello 的符号文件。 - - - -QEMU 将每个虚拟 CPU 表示为 GDB 中的一个线程，因此你可以使用 GDB 中所有的线程相关的命令去查看或维护 QEMU 的虚拟 CPU。 - - * `thread n` -GDB 在一个时刻只关注于一个线程（即：CPU）。这个命令将关注的线程切换到 n，n 是从 0 开始编号的。 - * `info threads` -列出所有的线程（即：CPU），包括它们的状态（活动还是停止）和它们在什么函数中。 - - - -##### QEMU - -QEMU 包含一个内置的监视器，它能够有效地检查和修改机器状态。想进入到监视器中，在运行 QEMU 的终端中按入 `Ctrl-a c` 即可。再次按下 `Ctrl-a c` 将切换回串行控制台。 - -监视器命令的完整参考资料，请查看 [QEMU 手册][2]。下面是 6.828 课程中用到的一些有用的命令： - - * `xp/ N x paddr` -显示从物理地址 paddr 处开始的 N 个词的十六进制转储。如果 N 省略，默认为 1。这是 GDB 的 `x` 命令模拟的物理内存。 - - * `info registers` -显示机器内部寄存器状态的一个完整转储。实践中，对于段选择器，这将包含机器的 _隐藏_ 段状态和局部、全局、和中断描述符表加任务状态寄存器。隐藏状态是在加载段选择器后，虚拟的 CPU 从 GDT/LDT 中读取的信息。下面是实验 1 中 JOS 内核处于运行中时的 CS 信息和每个字段的含义： -```c - CS =0008 10000000 ffffffff 10cf9a00 DPL=0 CS32 [-R-] -``` - - * `CS =0008` - -代码选择器可见部分。我们使用段 0x8。这也告诉我们参考全局描述符表（0x8 &4=0），并且我们的 CPL（当前权限级别）是 0x8&3=0。 - * `10000000` -这是段基址。线性地址 = 逻辑地址 + 0x10000000。 - * `ffffffff` -这是段限制。访问线性地址 0xffffffff 以上将返回段违规异常。 - * `10cf9a00` -段的原始标志，QEMU 将在接下来的几个字段中解码这些对我们有用的标志。 - * `DPL=0` -段的权限级别。一旦代码以权限 0 运行，它将就能够加载这个段。 - * `CS32` -这是一个 32 位代码段。对于数据段（不要与 DS 寄存器混淆了），另外的值还包括 `DS`，而对于本地描述符表是 `LDT`。 - * `[-R-]` -这个段是只读的。 - - * `info mem` -（在实验 2 以后）显示映射的虚拟内存和权限。比如： -``` - ef7c0000-ef800000 00040000 urw - efbf8000-efc00000 00008000 -rw - -``` - -这告诉我们从 0xef7c0000 到 0xef800000 的 0x00040000 字节的内存被映射为读取/写入/用户可访问，而映射在 0xefbf8000 到 0xefc00000 之间的内存权限是读取/写入，但是仅限于内核可访问。 - - * `info pg` -（在实验 2 以后）显示当前页表结构。它的输出类似于 `info mem`，但与页目录条目和页表条目是有区别的，并且为每个条目给了单独的权限。重复的 PTE 和整个页表被折叠为一个单行。例如： -``` - VPN range Entry Flags Physical page - [00000-003ff] PDE[000] -------UWP - [00200-00233] PTE[200-233] -------U-P 00380 0037e 0037d 0037c 0037b 0037a .. - [00800-00bff] PDE[002] ----A--UWP - [00800-00801] PTE[000-001] ----A--U-P 0034b 00349 - [00802-00802] PTE[002] -------U-P 00348 - -``` - -这里各自显示了两个页目录条目、虚拟地址范围 0x00000000 到 0x003fffff 以及 0x00800000 到 0x00bfffff。 所有的 PDE 都存在于内存中、可写入、并且用户可访问，而第二个 PDE 也是可访问的。这些页表中的第二个映射了三个页、虚拟地址范围 0x00800000 到 0x00802fff，其中前两个页是存在于内存中的、可写入、并且用户可访问的，而第三个仅存在于内存中，并且用户可访问。这些 PTE 的第一个条目映射在物理页 0x34b 处。 - - - - -QEMU 也有一些非常有用的命令行参数，使用 `QEMUEXTRA` 变量可以将参数传递给 JOS 的 makefile。 - - * `make QEMUEXTRA='-d int' ...` -记录所有的中断和一个完整的寄存器转储到 `qemu.log` 文件中。你可以忽略前两个日志条目、"SMM: enter" 和 "SMM: after RMS”，因为这些是在进入引导加载器之前生成的。在这之后的日志条目看起来像下面这样： -``` - 4: v=30 e=0000 i=1 cpl=3 IP=001b:00800e2e pc=00800e2e SP=0023:eebfdf28 EAX=00000005 - EAX=00000005 EBX=00001002 ECX=00200000 EDX=00000000 - ESI=00000805 EDI=00200000 EBP=eebfdf60 ESP=eebfdf28 - ... - -``` - -第一行描述了中断。`4:` 只是一个日志记录计数器。`v` 提供了十六进程的向量号。`e` 提供了错误代码。`i=1` 表示它是由一个 `int` 指令（相对一个硬件产生的中断而言）产生的。剩下的行的意思很明显。对于一个寄存器转储而言，接下来看到的就是寄存器信息。 - -注意：如果你运行的是一个 0.15 版本之前的 QEMU，日志将写入到 `/tmp` 目录，而不是当前目录下。 - - - --------------------------------------------------------------------------------- - -via: https://pdos.csail.mit.edu/6.828/2018/labguide.html - -作者：[csail.mit][a] -选题：[lujun9972][b] -译者：[qhwdw](https://github.com/qhwdw) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://pdos.csail.mit.edu -[b]: https://github.com/lujun9972 -[1]: http://sourceware.org/gdb/current/onlinedocs/gdb/ -[2]: http://wiki.qemu.org/download/qemu-doc.html#pcsys_005fmonitor diff --git a/translated/tech/20181004 Archiving web sites.md b/translated/tech/20181004 Archiving web sites.md deleted file mode 100644 index cca9ce3a09..0000000000 --- a/translated/tech/20181004 Archiving web sites.md +++ /dev/null @@ -1,119 +0,0 @@ -存档网站 -====== - -我最近深入研究了网站存档，因为有些朋友担心遇到糟糕的系统管理或恶意入侵时失去对在线托管的工作的控制。这使得网站存档成为任意系统管理员工具箱中的重要工具。事实证明，有些网站比其他网站更难存档。本文介绍了对传统网站进行存档的过程，并阐述在面对最新流行的单页面应用程序的现代网站时，它有哪些不足。 - -### 转换为简单网站 - -手动开发 HTML 网站的日子早已不复存在。现在的网站是动态的，并使用最新的 JavaScript，PHP 或 Python 框架即时构建。结果，这些网站更加脆弱：数据库崩溃，升级出错或者未修复的漏洞都可能使数据丢失。在我以前是一名 Web 开发人员时，我不得不接受客户希望网站基本上可以永久工作的想法。这种期望与 web 开发“快速行动和破除陈规”的理念不相符。在这方面，使用 [Drupal][2] 内容管理系统（CMS）尤其具有挑战性，因为重大更新会破坏与第三方模块的兼容性，这意味着客户很少承担的起高昂的升级成本。解决方案是将这些网站存档：以实时动态的网站为基础，将其转换为任何 web 服务器可以永久服务的纯 HTML 文件。此过程对你自己的动态网站非常有用，也适用于你想保护但无法控制的第三方网站。 - -对于简单的静态网站，古老的 [Wget][3] 程序就可以胜任。然而，镜像保存一个完整页面的方法，虽然复杂但很固定： - -``` - $ nice wget --mirror --execute robots=off --no-verbose --convert-links \ - --backup-converted --page-requisites --adjust-extension \ - --base=./ --directory-prefix=./ --span-hosts \ - --domains=www.example.com,example.com http://www.example.com/ - -``` - -以上命令下载了网页的内容，但也抓取了指定域名中的所有内容。在对你喜欢的网站执行此操作之前，请考虑此类抓取可能对网站产生的影响。上面的命令故意忽略了 `robots.txt` 规则，就像现在[档案管理者的习惯做法][4]，并尽可能快的存档网站。大多数抓取工具都可以选择点击暂停并限制带宽使用，以避免使网站瘫痪。 - -上面的命令还将获取 “page requisites（译者注：单页面所需的所有元素）”，像样式表（CSS），图像和脚本等。下载的页面内容将会被修改，以便链接也指向本地副本。任意 web 服务器均可托管生成的文件集，从而生成原始网站的静态副本。 - -以上所述是事情一切顺利的时候。任意使用过计算机的人都知道事情的进展很少如计划那样；各种各样的事情可以使程序以有趣的方式脱离正规。比如，在网站上有一个日历块很流行。内容管理系统会动态生成这些内容，这会使爬虫程序陷入死循环以尝试检索所有页面。灵巧的存档者可以使用正则表达式（例如 Wget 有一个 `--reject-regex` 选项）来忽略有问题的资源。如果可以访问网站的管理界面，另一个方法是禁用日历、登录表单、评论表单和其他动态区域。一旦网站变成静态的，（那些动态区域）也肯定会停止工作，因此从原始网站中移除这些杂乱的东西也不是全无意义。 - -### JavaScript 的厄运 - -很不幸，有些网站不仅仅是纯 HTML 文件构建的。比如，在单页面网站中，web 浏览器通过执行一个小的 JavaScript 程序来构建内容。像 Wget 这样的简单用户代理将难以重建这些网站的有意义的静态副本，因为它根本不支持 JavaScript。理论上，网站应该使用[渐进增强][5]技术，在不使用 JavaScript 的情况下提供内容和实现功能，但这些指示很少被遵循，因为使用 [NoScript][6] 或 [uMatrix][7] 等插件的人都很确定。 - -传统的存档方法有时是最愚蠢的方式，会导致失败。在尝试为一个本地报纸网站（[pamplemousse.ca][8]）创建备份时，我发现 WordPress 在末尾包含 JavaScript，且添加了查询字符串（例如：`?ver=1.12.4`）。这会使提供存档服务的 web 服务器不能正确进行内容类型检测，因为其靠文件扩展名来发送正确的 `Content-Type` 头部信息。在 web 浏览器加载此类存档时，这些脚本将无法加载，导致动态网站受损。 - -随着 web 向使用浏览器作为虚拟机执行任意代码转化，依赖于纯 HTML 文件解析的存档方法也需要随之适应。这个问题的解决方案是在抓取时记录（以及重现）服务器提供的 HTTP 头部信息，实际上专业的档案管理者就使用这种方法。 - -### 创建和显示 WARC 文件Creating and displaying WARC files - -在 [Internet Archive][9] 网站，Brewster Kahle 和 Mike Burner 在 1996 年设计了 [ARC][10] （用于 "ARChive"）文件格式，以提供一种聚合档案工作产生的百万个小文件的方法。该格式最终标准化为 WARC（“Web ARChive”）[规范][11]，并在 2009 年作为 ISO 标准发布，2017 年修订。标准化工作由[国际互联网保护联盟][12]（IIPC）领导，据维基百科称，这是一个“为共同保护未来互联网内容而建立的图书馆和国际组织”；它有美国国会图书馆和互联网档案馆等成员。后者内部在其基于 Java 的 [Heritrix crawler][13]（译者注：一种爬虫程序）上使用 WARC 格式。 - -WARC 在单个压缩文件中聚合了多种资源，像 HTTP 头部信息，文件内容，以及其他元数据。方便的是实际上 Wget 提供了 `--warc` 参数来支持 WARC 格式。不幸的是 web 浏览器不能直接显示 WARC 文件，所以为了访问存档文件，一个查看器或某些格式转换是很有必要的。我所发现的最简单的查看器是 [pywb][14]，它以 Python 包的形式运行一个简单的 web 服务器提供一个像网站时光倒流机网站的界面，来浏览 WARC 文件的内容。执行以下命令将会在 `http://localhost:8080/` 地址显示 WARC 文件的内容： - -``` - $ pip install pywb - $ wb-manager init example - $ wb-manager add example crawl.warc.gz - $ wayback - -``` - -顺便说一句，这个工具是由 [Webrecorder][15] 服务提供者建立的，Webrecoder 服务可以使用 web 浏览器保存动态页面的内容。 - -很不幸，pywb 无法加载 Wget 生成的 WARC 文件，因为它[遵循][16][不一致的 1.0 规范][17]，[1.1 规范修复了此问题][17]。就算 Wget 或 pywb 修复了这些问题，Wget 生成的 WARC 文件对我的使用来说不够可靠，所以我找了其他的替代品。引起我注意的爬虫程序简称 [crawl][19]。以下是它的调用方式： - -``` - $ crawl https://example.com/ - -``` - -（它的 README 文件说“非常简单”。）该程序确实支持一些命令行参数选项，但大多数默认值都是最佳的：它会从其他域获取页面需求（除非使用 `-exclude-related` 参数），但肯定不会递归出域。默认情况下，它会与远程站点建立十个并发连接，这个值可以使用 `-c` 参数更改。但是，最重要的是，生成的 WARC 文件可以使用 pywb 完美加载。 - -### 未来的工作和替代方案 - -这里还有更多有关使用 WARC 文件的[资源][20]。特别要提的是，这里有一个专门用来存档网站的 Wget 的直接替代品，叫做 [Wpull][21]。它实验性地支持了 [PhantomJS][22] 和 [youtube-dl][23] 的集成，即允许分别下载更复杂的 JavaScript 页面以及流媒体。该程序是一个叫做 [ArchiveBot][24] 的复杂档案工具的基础，ArchiveBot 被那些在 [ArchiveTeam][25] 的“零散离群的档案管理者、程序员、作家以及演说家”使用，他们致力于“在历史永远丢失之前保存他们”。集成 PhantomJS 好像并没有如团队期望的那样良好工作，所以 ArchiveTeam 也用其他的低等工具来镜像保存更复杂的网站。例如，[snscrape][26] 将抓取社交媒体配置文件以生成要发送到 ArchiveBot 的页面列表。团队使用的另一个工具是 [crocoite][27]，它在 Chrome 浏览器下以无头文件信息的模式来存档 JavaScript 较多的网站。 - -如果没有提到称做“网站复制者”的 [HTTrack][28] 项目，那么这篇文章算不上完整。工作方式和 Wget 相似，HTTrack 可以对远程站点创建一个本地的副本，但是不幸的是它不支持输出 WRAC 文件。对于不熟悉命令行的小白用户来说，它在人机交互方面显得更有价值。 - -同样，在我的研究中，我发现了叫做 [Wget2][29] 的 Wget 的完全重制版本，它支持多线程操作，这可能使它比前身更快。和 Wget 相比，它[舍弃了一些功能][30]，但是最值得注意的是拒绝模式、WARC 输出以及 FTP 支持，并增加了 RSS、DNS 缓存以及改进的 TLS 支持。 - -最后，我个人对这些工具的愿景是将他们与现有的书签系统集成起来。目前我在 [Wallabag][31] 中保留了一些有趣的链接，这是一种自托管式的“稍后阅读”服务，意在成为 [Pocket][32]（现在由 Mozilla 拥有）的免费替代品。但是 Wallabag 在设计上只保留了文章的“可读”副本，而不是一个完整的拷贝。在某些情况下，“可读版本”实际上[不可读][33]，并且 Wallabag 有时[无法解析文章][34]。恰恰相反，像 [bookmark-archiver][35] 或 [reminiscence][36] 这样其他的工具会保存页面的屏幕截图以及完整的 HTML 文件，但遗憾的是，它没有 WRAC 文件所以没有办法更可信的重现网页内容。 - -我所经历的有关镜像保存和存档的悲剧就是死数据。幸运的是，业余档案管理者可以利用工具将有趣的内容保存到网上。对于那些不想麻烦的人来说，互联网档案馆依然要留在这里，并且存档团队显然[正在为互联网档案馆本身做备份][37]。 - --------------------------------------------------------------------------------- - -via: https://anarc.at/blog/2018-10-04-archiving-web-sites/ - -作者：[Anarcat][a] -选题：[lujun9972](https://github.com/lujun9972) -译者：[fuowang](https://github.com/fuowang) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://anarc.at -[1]: https://anarc.at/blog -[2]: https://drupal.org -[3]: https://www.gnu.org/software/wget/ -[4]: https://blog.archive.org/2017/04/17/robots-txt-meant-for-search-engines-dont-work-well-for-web-archives/ -[5]: https://en.wikipedia.org/wiki/Progressive_enhancement -[6]: https://noscript.net/ -[7]: https://github.com/gorhill/uMatrix -[8]: https://pamplemousse.ca/ -[9]: https://archive.org -[10]: http://www.archive.org/web/researcher/ArcFileFormat.php -[11]: https://iipc.github.io/warc-specifications/ -[12]: https://en.wikipedia.org/wiki/International_Internet_Preservation_Consortium -[13]: https://github.com/internetarchive/heritrix3/wiki -[14]: https://github.com/webrecorder/pywb -[15]: https://webrecorder.io/ -[16]: https://github.com/webrecorder/pywb/issues/294 -[17]: https://github.com/iipc/warc-specifications/issues/23 -[18]: https://github.com/iipc/warc-specifications/pull/24 -[19]: https://git.autistici.org/ale/crawl/ -[20]: https://archiveteam.org/index.php?title=The_WARC_Ecosystem -[21]: https://github.com/chfoo/wpull -[22]: http://phantomjs.org/ -[23]: http://rg3.github.io/youtube-dl/ -[24]: https://www.archiveteam.org/index.php?title=ArchiveBot -[25]: https://archiveteam.org/ -[26]: https://github.com/JustAnotherArchivist/snscrape -[27]: https://github.com/PromyLOPh/crocoite -[28]: http://www.httrack.com/ -[29]: https://gitlab.com/gnuwget/wget2 -[30]: https://gitlab.com/gnuwget/wget2/wikis/home -[31]: https://wallabag.org/ -[32]: https://getpocket.com/ -[33]: https://github.com/wallabag/wallabag/issues/2825 -[34]: https://github.com/wallabag/wallabag/issues/2914 -[35]: https://pirate.github.io/bookmark-archiver/ -[36]: https://github.com/kanishka-linux/reminiscence -[37]: http://iabak.archiveteam.org diff --git a/translated/tech/20181005 Dbxfs - Mount Dropbox Folder Locally As Virtual File System In Linux.md b/translated/tech/20181005 Dbxfs - Mount Dropbox Folder Locally As Virtual File System In Linux.md new file mode 100644 index 0000000000..889fb00ac8 --- /dev/null +++ b/translated/tech/20181005 Dbxfs - Mount Dropbox Folder Locally As Virtual File System In Linux.md @@ -0,0 +1,136 @@ +Dbxfs - 在 Linux 中本地挂载 Dropbox 文件夹作为虚拟文件系统 +====== + +![](https://www.ostechnix.com/wp-content/uploads/2018/10/dbxfs-720x340.png) + +不久前，我们总结了所有**[在本地挂载 Google Drive][1]**作为虚拟文件系统，并从 Linux 系统访问存储在 Google Drive 中的文件的方法。今天，我们将学习使用 **dbxfs**将 Dropbox 文件夹挂载到本地文件系统中。dbxfs 用于在类 Unix 操作系统中本地挂载 Dropbox 文件夹作为虚拟文件系统。虽然在 Linux 中很容易[**安装 Dropbox 客户端**][2]，但这种方法与官方方法略有不同。它是一个命令行 dropbox 客户端，且无需磁盘空间即可访问。dbxfs 是免费、开源的，并且是用 Python 3.5+ 编写的。 + +### 安装 dbxfs + +dbxfs 官方支持 Linux 和 Mac OS。但是，它应该适用于任何提供 **FUSE 兼容库**或能够挂载 **SMB** 共享的 POSIX 系统。由于它是用 Python 3.5 编写的，因此可以使用 **pip3** 包管理器进行安装。如果尚未安装 PIP，请参阅以下指南。 + +[如何使用 pip 管理 Python 包][13] + +并且也要安装 FUSE 库。 + +在基于 Debian 的系统上，运行以下命令以安装 FUSE： + +``` +$ sudo apt install libfuse2 + +``` + +在 Fedora 上： + +``` +$ sudo dnf install fuse + +``` + +安装完所有必需的依赖项后，运行以下命令以安装 dbxfs： + +``` +$ pip3 install dbxfs + +``` + +### 在本地挂载 Dropbox 文件夹 + +创建一个挂载点以将 Dropbox 文件夹挂载到本地文件系统中。 + +``` +$ mkdir ~/mydropbox + +``` + +然后，使用 dbxfs 在本地挂载 dropbox 文件夹，如下所示： + +``` +$ dbxfs ~/mydropbox + +``` + +你将被要求生成一个访问令牌： + +![](https://www.ostechnix.com/wp-content/uploads/2018/10/Generate-access-token-1.png) + +要生成访问令牌，只需在 Web 浏览器中输入上面输出的 URL，然后单击**允许** 以授权 Dropbox 访问。你需要登录 Dropbox 帐户才能完成授权过程。 + +下一个页面将生成新的授权码。复制代码并返回终端将其粘贴到 cli-dbxfs 提示符中以完成该过程。 + +然后，系统会要求你保存凭据以供将来访问。无论你是要保存还是拒绝，输入 **Y** 或 **N**。然后，你需要为新的访问令牌输入两次密码。 + +最后，输入 **Y** 接受 **“/home/username/mydropbox”** 作为默认挂载点。如果你要设置不同的路径，输入 **N** 并输入你选择的位置。 + +[![Generate access token 2][3]][4] + +完成了！从现在开始，你可以看到你的 Dropbox 文件夹已挂载到本地文件系统中。 + +![](https://www.ostechnix.com/wp-content/uploads/2018/10/Dropbox-in-file-manager.png) + +### 更改访问令牌存储路径 + +默认情况下，dbxfs 会将 Dropbox 访问令牌存储在系统密钥环或加密文件中。但是，你可能希望将其存储在 **gpg** 加密文件或其他地方。如果是这样，请在 [Dropbox 开发者应用控制台][5]上创建个人应用来获取访问令牌。 + +![](https://www.ostechnix.com/wp-content/uploads/2018/10/access-token.png) + +创建应用后，单击下一步中的**生成**按钮。此令牌可用于通过 API 访问你的 Dropbox 帐户。不要与任何人共享你的访问令牌。 + +![](https://www.ostechnix.com/wp-content/uploads/2018/10/Create-a-new-app.png) + +创建访问令牌后，使用任何你选择的加密工具对其进行加密，例如 [**Cryptomater**][6]、[**Cryptkeeper**][7]、[**CryptGo**][8]、[**Cryptr**][9]、[**Tomb**][10]、[**Toplip**][11] 和 [**GnuPG**][12] 等，并在你喜欢的位置保存。 + +接下来编辑 dbxfs 配置文件并添加以下行： + +``` +"access_token_command": ["gpg", "--decrypt", "/path/to/access/token/file.gpg"] + +``` + +你可以通过运行以下命令找到 dbxfs 配置文件： + +``` +$ dbxfs --print-default-config-file + +``` + +有关更多详细信息，请参阅 dbxfs 帮助： + +``` +$ dbxfs -h + +``` + +如你所见，使用 dbxfs 在你的文件系统中本地挂载 Dropfox 文件夹没什么大不了的。经过测试，dbxfs 如常工作。如果你有兴趣了解它是如何工作的，请尝试一下，并在下面的评论栏告诉我们你的体验。 + +就是这些了。希望这篇文章有用。还有更多好东西。敬请期待！ + +干杯! + + + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/dbxfs-mount-dropbox-folder-locally-as-virtual-file-system-in-linux/ + +作者：[SK][a] +选题：[lujun9972](https://github.com/lujun9972) +译者：[geekpi](https://github.com/geekpi) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[1]: https://www.ostechnix.com/how-to-mount-google-drive-locally-as-virtual-file-system-in-linux/ +[2]: https://www.ostechnix.com/install-dropbox-in-ubuntu-18-04-lts-desktop/ +[3]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[4]: http://www.ostechnix.com/wp-content/uploads/2018/10/Generate-access-token-2.png +[5]: https://dropbox.com/developers/apps +[6]: https://www.ostechnix.com/cryptomator-open-source-client-side-encryption-tool-cloud/ +[7]: https://www.ostechnix.com/how-to-encrypt-your-personal-foldersdirectories-in-linux-mint-ubuntu-distros/ +[8]: https://www.ostechnix.com/cryptogo-easy-way-encrypt-password-protect-files/ +[9]: https://www.ostechnix.com/cryptr-simple-cli-utility-encrypt-decrypt-files/ +[10]: https://www.ostechnix.com/tomb-file-encryption-tool-protect-secret-files-linux/ +[11]: https://www.ostechnix.com/toplip-strong-file-encryption-decryption-cli-utility/ +[12]: https://www.ostechnix.com/an-easy-way-to-encrypt-and-decrypt-files-from-commandline-in-linux/ +[13]:https://www.ostechnix.com/manage-python-packages-using-pip/ \ No newline at end of file diff --git a/translated/tech/20181206 How To Boot Into Rescue Mode Or Emergency Mode In Ubuntu 18.04.md b/translated/tech/20181206 How To Boot Into Rescue Mode Or Emergency Mode In Ubuntu 18.04.md new file mode 100644 index 0000000000..9d5836b921 --- /dev/null +++ b/translated/tech/20181206 How To Boot Into Rescue Mode Or Emergency Mode In Ubuntu 18.04.md @@ -0,0 +1,106 @@ +[#]: collector: (lujun9972) +[#]: translator: (geekpi) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (How To Boot Into Rescue Mode Or Emergency Mode In Ubuntu 18.04) +[#]: via: (https://www.ostechnix.com/how-to-boot-into-rescue-mode-or-emergency-mode-in-ubuntu-18-04/) +[#]: author: (SK https://www.ostechnix.com/author/sk/) + +如何在 Ubuntu 18.04 中启动到救援模式或紧急模式 +====== +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Boot-Into-Rescue-Mode-Or-Emergency-Mode-720x340.png) + +正如你可能已经知道的那样，**runlevel** 在许多最近的 Linux 发行版（如 RHEL 7 和 Ubuntu 16.04 LTS）中被 **systemd target** 替换。有关 runlevel 和 systemd target 的更多详细信息，请参阅[**本指南**][1]。在这个简短的教程中，我们将看到如何启动**救援模式**以及**紧急模式**。本指南在 Ubuntu 18.04 LTS 中进行了测试，但是下面给出的步骤适用于大多数使用 systemd 作为默认服务管理器的 Linux 发行版。在进一步讨论之前，让我澄清什么是救援模式和紧急模式以及这两种模式的目的是什么。 + +### 什么是救援模式？ + +**救援模式**相当于使用 **SysV** 作为默认服务管理器的 Linux 发行版中的 **单用户模式**。在救援模式下，将挂载所有本地文件系统，仅启动一些重要服务。但是，不会启动正常服务（例如网络服务）。救援模式在系统无法正常启动的情况下很有用。此外，我们可以在救援模式下执行一些重要的救援操作，例如[**重置 root 密码**][2]。 + +### 什么是紧急模式？ + +与救援模式相比，在**紧急模式**中不启动任何东西。没有服务启动、没有挂载点、没有建立套接字，什么也没有。你所拥有的只是一个**原始的 shell**。紧急模式适用于调试目的。 + +### 在 Ubuntu 18.04 LTS 中进入救援模式 + +启动你的 Ubuntu 系统。出现 Grub 菜单时，选择第一条并按下 **e** 进行编辑。 + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Grub-menu.png) + +如果你没有看到 Grub 菜单，只需在 BIOS logo 消失后立即按下 ESC 键。 + +找到以单词 **“linux”** 开头的行，并在该行的末尾添加以下行（要到达末尾，只需按下 **CTRL+e** 或使用 END 键或左右箭头键）： + +``` +systemd.unit=rescue.target +``` + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Edit-grub-menu.png) + +添加完成后，只需按下 **CTRL+x** 或 **F10** 即可继续启动救援模式。几秒钟后，你将以 root 用户身份进入救援模式（单用户模式）。以下是 Ubuntu 18.04 LTS 服务器版中救援模式的样子： + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/Ubuntu-rescue-mode.png) + +接下来，输入以下命令将根 （/） 文件系统挂载成读/写模式。 + +``` +mount -n -o remount,rw / +``` + +### 启动到紧急模式 + +将 Ubuntu 引导到紧急模式与上述方法相同。你只需在编辑 grub 菜单时将 “systemd.unit=rescue.target” 替换为 “systemd.unit=emergency.target” 即可。 + +[![emergency mode][3]][4] + +添加 “systemd.unit=emergency.target” 后，按下 **Ctrl+x** 或 **F10** 继续启动到紧急模式。 + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/emergency-mode-1.png) + +最后，你可以使用以下命令将根文件系统挂载成读/写模式： + +``` +mount -n -o remount,rw / +``` + +### 在救援模式和紧急模式之间切换 + +如果你处于救援模式，则不必像上面提到的那样编辑 grub 条目。相反，只需输入以下命令即可立即切换到紧急模式： + +``` +systemctl emergency +``` + +同样，要从紧急模式切换到救援模式，请输入： + +``` +systemctl rescue +``` + +你现在知道了什么是救援模式和紧急模式以及如何在 Ubuntu 18.04 中启动这些模式。就像我已经提到的，这里提供的步骤将适用于许多使用 systemd 的 Linux 版本。 + +就是这些了。希望这篇文章有用。 + +还有更多好东西。敬请期待！ + +干杯！ + + + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/how-to-boot-into-rescue-mode-or-emergency-mode-in-ubuntu-18-04/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[geekpi](https://github.com/geekpi) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: https://www.ostechnix.com/check-runlevel-linux/ +[2]: https://www.ostechnix.com/how-to-reset-or-recover-root-user-password-in-linux/ +[3]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 +[4]: http://www.ostechnix.com/wp-content/uploads/2018/12/emergency-mode.png \ No newline at end of file diff --git a/translated/tech/20181210 McFly - A Replacement To ‘Ctrl-R- Bash History Search Feature.md b/translated/tech/20181210 McFly - A Replacement To ‘Ctrl-R- Bash History Search Feature.md new file mode 100644 index 0000000000..5031edc985 --- /dev/null +++ b/translated/tech/20181210 McFly - A Replacement To ‘Ctrl-R- Bash History Search Feature.md @@ -0,0 +1,155 @@ +[#]: collector: (lujun9972) +[#]: translator: (FSSlc) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (McFly – A Replacement To ‘Ctrl+R’ Bash History Search Feature) +[#]: via: (https://www.ostechnix.com/mcfly-a-replacement-to-ctrlr-bash-history-search-feature/) +[#]: author: (SK https://www.ostechnix.com/author/sk/) + +McFly – Bash 历史命令搜索特性的一个替代品 +====== +![](https://www.ostechnix.com/wp-content/uploads/2018/12/mcfly-720x340.png) + +假如你在命令行模式下花费过很长时间，那么你必定使用过或者听说过 BASH 的 **反向搜索** 功能，在 Bash 中执行反向搜索功能的快捷键是 **Ctrl+r**。通过使用这个特性，我们可以找到我们执行过的命令而无需再次输入它们。当然，你可以使用上下键来搜索你的 bash 命令记录，但使用 Ctrl+r 快捷键可以让这个搜索过程更简单快速。今天我找寻到了 Bash 历史命令搜索特性 ‘Ctrl+r’ 的一个替代品，它就是 **“McFly”**。McFly 是一个使用 **Rust** 编程语言写就的简洁工具，自带一个智能的搜索引擎，用来替换默认的 Ctrl+r 这个 Bash 历史命令搜索特性。 McFly 提供的命令建议都是通过一个小巧的 **神经网络** 来实时排序给出的。 + +McFly 重新绑定了 Ctrl+r 快捷键，可以从你的 Bash 历史命令中找到所有最近执行过的命令。它通过追溯下面的信息来增强你的 shell 历史命令搜索特性： + +* 命令结束状态 +* 当你运行命令时的时间戳 +* 以及你运行命令的执行目录 + +它将所有追溯的信息保存在一个 SQLite 数据库中。由于它追溯了命令的历史结束状态，所以你可以很轻易地忽略掉失败的命令。听起来很酷，对吧？ + +在给出一个命令建议时，它将考虑如下因素： + +* 你在哪个目录执行的这个命令，将来你很有可能在相同的目录重复这个命令 +* 在你执行这个命令之前，执行过什么命令 +* 你执行这个命令有多频繁 +* 你最后执行该命令的时间 +* 你是否在 McFly 中选择过这个命令 +* 以及这个命令的历史结束状态。因为你很有可能不会去执行失败过的命令，对吧？ + +McFly 维护着你的默认 Bash 历史文件，所以你可以随时停止使用它。McFly 也并不只服务于 BASH， 它也可以扩展到其他 shell 程序。 + +### 安装 McFly + +在 Linux 中，McFly 可以使用 Linuxbrew 来安装。如若你还没有安装过 Linuxbrew，那么你可以参考下面的这个链接。（译者注：从其github 主页了解到也可以下载其二进制来使用。） + +[Linuxbrew —— 一个使用 Linux 和 Mac OS X 的通用包管理][1] + +一旦安装好了 Linuxbrew，运行下面的命令来安装 McFly： + +``` +$ brew tap cantino/mcfly https://github.com/cantino/mcfly + +$ brew install mcfly +``` + +在安装完成后，你将看到下面的输出： + +``` +==> Installing mcfly from cantino/mcfly +==> Downloading https://github.com/cantino/mcfly/releases/download/v0.2.5/mcfly-v0 +==> Downloading from https://github-production-release-asset-2e65be.s3.amazonaws.c +######################################################################## 100.0% +==> ONE MORE STEP! Edit ~/.bashrc and add the following: + +if [ -f $(brew --prefix)/opt/mcfly/mcfly.bash ]; then +. $(brew --prefix)/opt/mcfly/mcfly.bash +fi +🍺 /home/linuxbrew/.linuxbrew/Cellar/mcfly/v0.2.5: 4 files, 3.5MB, built in 33 seconds +``` + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/install-mcfly.png) +正如你上面看到的那样，在使用 McFly 之前我们需要再做一些配置。 + +将下面几行添加到你的 **~/.bashrc** 文件中： + +``` +if [ -f $(brew --prefix)/opt/mcfly/mcfly.bash ]; then +. $(brew --prefix)/opt/mcfly/mcfly.bash +fi +``` + +最后，再运行下面的命令来让更改生效。 + +``` +$ source ~/.bashrc +``` + +当你第一次执行上面的这个命令时，你的 BASH 历史将会被导入 McFly 的数据库。依据你的 bash 历史文件的大小，这个过程将花费一些时间。一旦导入完成，你讲看到下面的提示信息。 + +``` +McFly: Importing Bash history for the first time. This may take a minute or two...done. +``` + +现在你就可以使用 McFly 了。 + +### 使用方法 + +要在你的命令中执行搜索，只需要键入 ‘mcfly search’ 再加上命令名的一部分，最后敲击 ENTER 键即可。Mcfly 将会基于你刚才键入的搜索查询语句给出命令建议。 + +``` +$ mcfly search +``` + +例如我键入了下面的命令： + +``` +$ mcfly search mk +``` + +下面展示的是我 Ubuntu 机子上的示例输出： + +![](https://www.ostechnix.com/wp-content/uploads/2018/12/mcfly-command-1.png) + +如你所见，我已经使用过 'mkdir' 这个命令两次。假如你想从这些命令建议中执行其中之一，只需使用上下键来选择它，然后敲击 ENTER 键来执行它就可以了。假如你想编辑其中一个命令，则需要先选择它，然后敲 **TAB** 键将这个命令放置到终端中，最后在运行它之前更改它就行了。要从历史中删除已经选择的命令，按 **F2** 即可。 + +或者，输入下面的命令来打开历史搜索，然后输入任意一个命令或者命令的一部分来从你的历史命令中查看它提供的建议。 + +``` +$ mcfly search +``` + +在你输入的同时， McFly 将会展示命令的提示。 + +下面是一个介绍 McFly 的简短演示视频： +![](https://www.ostechnix.com/wp-content/uploads/2018/12/mcfly-demo.gif) + +你还可以使用下面的命令来查看帮助： + +``` +$ mcfly --help +``` + +### 移除 McFly + +不喜欢 McFly，没问题！可以使用下面的命令来移除它： + +``` +$ brew uninstall mcfly + +$ brew untap cantino/mcfly +``` + +最后，移除先前添加到 **~/.bashrc** 文件中的几行命令。 + +好了，这些就是所有了，更多精彩内容敬请期待，请保存关注！ + +Cheers! + +-------------------------------------------------------------------------------- + +via: https://www.ostechnix.com/mcfly-a-replacement-to-ctrlr-bash-history-search-feature/ + +作者：[SK][a] +选题：[lujun9972][b] +译者：[FSSlc](https://github.com/FSSlc) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.ostechnix.com/author/sk/ +[b]: https://github.com/lujun9972 +[1]: https://www.ostechnix.com/linuxbrew-common-package-manager-linux-mac-os-x/ diff --git a/translated/tech/20181222 Top 11 best Image Viewer for Ubuntu and other Linux.md b/translated/tech/20181222 Top 11 best Image Viewer for Ubuntu and other Linux.md new file mode 100644 index 0000000000..3125ef4db3 --- /dev/null +++ b/translated/tech/20181222 Top 11 best Image Viewer for Ubuntu and other Linux.md @@ -0,0 +1,326 @@ +[#]: collector: (lujun9972) +[#]: translator: (zhs852) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Top 11 best Image Viewer for Ubuntu and other Linux) +[#]: via: (https://itsfoss.com/image-viewers-linux/) +[#]: author: (Ankush Das https://itsfoss.com/author/ankush/) + +Linux 下最棒的 11 个图片查看器 +====== + +如果不是因为系统自带的图片查看器没有你想要的功能，或者你想要更棒的体验，你大概不会想切换到其它图片查看器吧。 + +不过，如果你喜欢折腾，你可能就会想用不同的图片查看器了吧。我猜最终你会被新图片查看器的全新用户体验或特色功能所吸引的。 + +在本篇文章中，无论是简单的还是复杂的、无论是为 Ubuntu 准备的还是其它 Linux 发行版准备的，我们都有提到。 + +### Linux 下最棒的图片查看器 + +![Ubuntu 或其它 Linux 发行版适用的最棒的图片查看器][1] + +**注意：** 在准备安装一个图片查看器时，请前往您系统中预先安装的软件商店中查找。如果您没有任何软件商店或无法在软件商店中找到它，请手动执行我们给出的命令。 + +#### 1. Nomacs + +![Nomacs 图片查看器][2] + +**它有什么特点？** + + * 轻快 + * 内建图像调整工具（可以调整色彩和大小） + * 拍摄位置信息 + * 元数据调节器 + * 局域网同步 + * 全屏模式 + +Nomacs 是一款自由软件。虽然没有什么出众的功能，但是它的兼容性还不错，可以支持许多常见格式。 + +它的界面超级简单，但是提供了简单的图片编辑功能（可以调整色彩、亮度、大小）。除此之外，它还支持全屏模式、元数据调整等功能。 + +**我该如何安装它？** + +简单起见，你可以在各种软件中心中安装它。如果你想通过终端安装它，请参见它的 [GitHub 界面][3] 。或者，在使用 APT 包管理的系统中使用如下命令安装： + +``` +sudo apt install nomacs +``` + +#### 2. Gnome 之眼 +![Gnome 之眼][4] + +**它有什么特点？** + + * 极其简单的图像查看器 + * 幻灯片视图 + * 为 GNOME 量身打造的图片查看器 + +这是一款经典的图片查看器，它在数年前作为 GNOME 项目的一部分被开发出来。不过需要注意的是，对它的维护目前已经不是很活跃了。不过它仍能在最新版 Ubuntu LTS 和部分 Linux 发行版中正常工作。 + +如果你需要一个简单、有幻灯片视图并可以在侧栏看到元数据的图像查看器，Gnome 之眼是最佳选择。 + +**我该如何安装它？** + +若要在 Ubuntu 及基于 Ubuntu 的 Linux 发行版上安装它，仅需一条命令： + +``` +sudo apt install eog +``` + +如果你想在其它发行版中安装它，请参见 [项目的 GitHub 页面][5] 。 + +#### 3. EOM + +![EOM 图像查看器][6] + +**它有什么特点？** + + * 简洁 + * 可扩展 + * 为 MATE 量身打造的图片查看器 + +另一个基本功能齐全，支持幻灯片视图和图像旋转的查看器。 + +虽然它没什么特色功能，但它支持大部分的图像格式，并且还能处理大体积的图像。 + +**我该如何安装它？** + +若要在 Ubuntu 及基于 Ubuntu 的 Linux 发行版上安装它，仅需一条命令： + +``` +sudo apt install eom +``` + +如果你想在其它发行版中安装它，请参见 [项目的 GitHub 页面][7] 。 + +#### 4. Geeqie +![Geeqie 图像查看器][8] + +**它有什么特点？** + + * 可扩展 + * 色彩信息显示 + +Geeqie 是一个令用户印象深刻的图片管理/查看器。他支持将其它查看器作为扩展使用，不过它并不提供任何对图像操作的工具。 + +如果你希望获取图像的颜色信息、元数据，或是查看/管理一堆图片，它将会是一个不错的选择。 + +**我该如何安装它？** + +在终端输入： + +``` +sudo apt install geeqie +``` + +若想查看它的源代码，请前往 [它的 GitHub 主页][9]。 + +#### 5. gThumb + +![gThumb 图片查看器][10] + +**它有什么特点？** + + * 多种功能（查看、编辑和管理） + * 可清除 EXIF 信息 + * 图像格式转换 + * 查找重复的图像 + +gThumb 会让你眼前一亮，因为它有很多功能。它的查看/管理界面和编辑工具（裁剪、颜色编辑等等）将会给你留下很深的印象。 + +你甚至可以为图像添加评论或清除它的 EXIF 信息。它使得你可以方便地编辑或转码图像。 + +**我该如何安装它？** + +你可以在终端中输入这条命令： + +``` +sudo apt install gthumb +``` + +输了没用？请参阅 [项目 GitHub 主页][11] 来获取帮助。 + +#### 6. Gwenview +![Gwenview 图像查看器][12] + +**它有什么特点？** + + * 简单，有基础图像编辑功能（旋转、调整大小） + * 可使用 KIPI 插件扩展 + +Gwenview 又是一个基本的图像查看器，它为 KDE 量身定做。不过这并不影响你在其它桌面环境中使用它。 + +如果你使用 Konqueror 浏览器，你可以将 Gwenview 作为它的内嵌图片浏览器。你也可以为图片添加评论。此外，它还支持 [KIPI][13] 插件。 + +**我该如何安装它？** + +你可以在终端中输入这条命令： + +``` +sudo apt install gwenview +``` + +若想查看它的源代码，请前往 [它的 GitHub 主页][14]。 + +#### 7. Mirage + +![Mirage 图像查看器][15] + +**它有什么特点？** + + * 可定制的 UI + * 基本图像编辑工具 + * 可在命令行使用 + +如果你想要一个可在命令行中访问、支持全屏和幻灯片视图、带有基础编辑工具以及可定制 UI 的查看器，Mirage 是个不二之选。 + +它是一个非常快速且兼容性优良的查看器。它支持包括 png、jpg、svg、xpm、gif、bmp 和 tifff 在内的多种图像格式。 + +**我该如何安装它？** + +你需要执行： + +``` +sudo apt install mirage +``` + +访问 [项目 GitHub 页面][16] 来获取更多信息。 + +#### 8. KPhotoAlbum +![KPhotoAlbum][17] + +**它有什么特点？** + + * 为图像添加标签 + * 数据库支持 + * 图片比较 + * 合并/移除一堆图像 + +确切地说，KPhotoAlbum 其实不仅仅是一款图像查看器，它还能为图像添加标签并管理图像。 + +你可以用它来比较图片以及使用标签搜索你的图片。你还可以使用幻灯片视图来观看图片。 + +**我该如何安装它？** + +在终端中输入： + +``` +sudo apt kphotoalbum +``` + +跟从 [官网上的指引][18] 来在其它 Linux 发行版中安装它。 + +#### 9. Shotwell + +![Shotwell][19] + +**它有什么特点？** + + * 红眼消除工具 + * 将照片上传到 Facebook 或 Flickr 等社交网络中 + * 支持原始格式（RAW）的图片 + +Shotwell 是一个多功能照片管理器。在此，你能查看或管理你的照片。虽然它没带有许多图像编辑工具，但是你还是可以裁剪和调整亮度的。 + +**我该如何安装它？** + +在终端中执行以下命令 (Ubuntu 及其衍生版本)： + +``` +sudo apt install shotwell +``` + +若想获取更多信息，请 [前往它的 GitHub 界面][20]。 + +#### 10. Ristretto + +![Ristretto][21] + +**它有什么特点？** + + * 极其简单 + * 全屏模式 + * 幻灯片视图 + +简易的图像查看器。它能查看、全屏查看、缩放查看或以幻灯片视图查看图片。 + +它是为 Xfce 定制的，但你仍然可以在其它任何地方安装它。 + +**我该如何安装它？** + +即使它是为 Xfce 桌面环境构建的，你仍能在其它地方安装它。对 Ubuntu 及其衍生发行版，请执行： + +``` +sudo apt install ristretto +``` + +#### 11. digiKam + +![digiKam 图像查看器][22] + +**它有什么特点？** + + * 带有高级图像管理功能（查看/管理/编辑）的多合一查看器 + * 可以进行批处理 + * 带有 [Light Table 功能][23] + +digiKam 是一个带有多种图像编辑功能的高级照片管理器。你可以使用 SQLite 或 MySQL 来配置它的数据库。 + +为了提升你的看图体验，你可以在预览图片时加载低画质的图片。这样一来，即使你有一大堆图片，它也丝滑般流畅。不仅如此，你还可以通过 Google、Facebook、Imgur 等来导入/导出图片。如果你希望使用一个超多功能的查看器，请务必试试这个 digiKam。 + +**我该如何安装它？** + +执行这条命令： + +``` +sudo apt install digikam +``` + +访问 [项目 GitHub 页面][24] 来获取更多信息。 + +### 尾声 + +总的来说，无论你想要不同的用户体验、丰富的功能还是强大的管理工具，上面总有适合你的工具。 + +你更喜欢哪个图像查看器呢？它是系统自带的吗？ + +欢迎前往原文的评论区留下你的答案。 + +-------------------------------------------------------------------------------- + +via: https://itsfoss.com/image-viewers-linux/ + +作者：[Ankush Das][a] +选题：[lujun9972][b] +译者：[zhs852](https://github.com/zhs852) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://itsfoss.com/author/ankush/ +[b]: https://github.com/lujun9972 +[1]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/best-image-viewers-linux.png?resize=800%2C450&ssl=1 +[2]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/12/nomacs-image-viewer.jpg?resize=800%2C455&ssl=1 +[3]: https://github.com/nomacs/nomacs +[4]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/eye-of-gnome-image-viewer.jpg?resize=800%2C470&ssl=1 +[5]: https://github.com/GNOME/eog +[6]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/12/eye-of-mate-image-viewer.jpg?resize=800%2C464&ssl=1 +[7]: https://github.com/mate-desktop/eom +[8]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/12/geeqie-image-viewer.jpg?resize=800%2C444&ssl=1 +[9]: https://github.com/BestImageViewer/geeqie +[10]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/12/gthumb-image-viewer.jpg?resize=800%2C515&ssl=1 +[11]: https://github.com/GNOME/gthumb +[12]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2018/12/gwenview-image-viewer.jpg?resize=800%2C517&ssl=1 +[13]: https://en.wikipedia.org/wiki/KDE_Image_Plugin_Interface +[14]: https://github.com/KDE/gwenview +[15]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/mirage-image-viewer.jpg?resize=800%2C475&ssl=1 +[16]: https://github.com/xiongchiamiov/Mirage +[17]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2018/12/kphotoalbum-viewer.jpg?fit=800%2C522&ssl=1 +[18]: https://www.kphotoalbum.org/download/ +[19]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/shotwell-image-viewer.jpg?resize=800%2C473&ssl=1 +[20]: https://github.com/GNOME/shotwell +[21]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/ristretto-image-viewer.jpg?resize=800%2C437&ssl=1 +[22]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2018/12/digitkam-image-viewer.jpg?resize=800%2C550&ssl=1 +[23]: https://docs.kde.org/trunk5/en/extragear-graphics/digikam/using-lighttable.html +[24]: https://github.com/KDE/digikam diff --git a/中文排版指北.md b/中文排版指北.md deleted file mode 100644 index 9888b4dbc1..0000000000 --- a/中文排版指北.md +++ /dev/null @@ -1,294 +0,0 @@ -# 中文文案排版指北 -[![devDependency Status](https://david-dm.org/mzlogin/chinese-copywriting-guidelines/dev-status.svg)](https://david-dm.org/mzlogin/chinese-copywriting-guidelines#info=devDependencies) - -统一中文文案、排版的相关用法，降低团队成员之间的沟通成本，增强网站气质。 - -Other languages: - -- [English](https://github.com/mzlogin/chinese-copywriting-guidelines/blob/Simplified/README.en.md) -- [Chinese Traditional](https://github.com/sparanoid/chinese-copywriting-guidelines) -- [Chinese Simplified](README.md) - ------ - -## 目录 - -- [空格](#空格) - - [中英文之间需要增加空格](#中英文之间需要增加空格) - - [中文与数字之间需要增加空格](#中文与数字之间需要增加空格) - - [数字与单位之间需要增加空格](#数字与单位之间需要增加空格) - - [全角标点与其他字符之间不加空格](#全角标点与其他字符之间不加空格) - - [`-ms-text-autospace` to the rescue?](#-ms-text-autospace-to-the-rescue) -- [标点符号](#标点符号) - - [不重复使用标点符号](#不重复使用标点符号) -- [全角和半角](#全角和半角) - - [使用全角中文标点](#使用全角中文标点) - - [数字使用半角字符](#数字使用半角字符) - - [遇到完整的英文整句、特殊名词，其內容使用半角标点](#遇到完整的英文整句特殊名词其內容使用半角标点) -- [名词](#名词) - - [专有名词使用正确的大小写](#专有名词使用正确的大小写) - - [不要使用不地道的缩写](#不要使用不地道的缩写) -- [争议](#争议) - - [链接之间增加空格](#链接之间增加空格) -  - [简体中文不要使用直角引号](#简体中文不要使用直角引号) -- [工具](#工具) -- [谁在这样做？](#谁在这样做) -- [参考文献](#参考文献) - -## 空格 - -「有研究显示，打字的时候不喜欢在中文和英文之间加空格的人，感情路都走得很辛苦，有七成的比例会在 34 岁的时候跟自己不爱的人结婚，而其余三成的人最后只能把遗产留给自己的猫。毕竟爱情跟书写都需要适时地留白。 - -与大家共勉之。」——[vinta/paranoid-auto-spacing](https://github.com/vinta/pangu.js) - -### 中英文之间需要增加空格 - -正确： - -> 在 LeanCloud 上，数据存储是围绕 `AVObject` 进行的。 - -错误： - -> 在LeanCloud上，数据存储是围绕`AVObject`进行的。 - -> 在 LeanCloud上，数据存储是围绕`AVObject` 进行的。 - -完整的正确用法： - -> 在 LeanCloud 上，数据存储是围绕 `AVObject` 进行的。每个 `AVObject` 都包含了与 JSON 兼容的 key-value 对应的数据。数据是 schema-free 的，你不需要在每个 `AVObject` 上提前指定存在哪些键，只要直接设定对应的 key-value 即可。 - -例外：「豆瓣FM」等产品名词，按照官方所定义的格式书写。 - -### 中文与数字之间需要增加空格 - -正确： - -> 今天出去买菜花了 5000 元。 - -错误： - -> 今天出去买菜花了 5000元。 - -> 今天出去买菜花了5000元。 - -### 数字与单位之间需要增加空格 - -正确： - -> 我家的光纤入户宽带有 10 Gbps，SSD 一共有 20 TB。 - -错误： - -> 我家的光纤入户宽带有 10Gbps，SSD 一共有 10TB。 - -例外：度／百分比与数字之间不需要增加空格： - -正确： - -> 今天是 233° 的高温。 - -> 新 MacBook Pro 有 15% 的 CPU 性能提升。 - -错误： - -> 今天是 233 ° 的高温。 - -> 新 MacBook Pro 有 15 % 的 CPU 性能提升。 - -### 全角标点与其他字符之间不加空格 - -正确： - -> 刚刚买了一部 iPhone，好开心！ - -错误： - -> 刚刚买了一部 iPhone ，好开心！ - -### `-ms-text-autospace` to the rescue? - -Microsoft 有个 [`-ms-text-autospace`](http://msdn.microsoft.com/en-us/library/ie/ms531164(v=vs.85).aspx) 的 CSS 属性可以实现自动为中英文之间增加空白。不过目前并未普及，另外在其他应用场景，例如 OS X、iOS 的用户界面目前并不存在这个特性，所以请继续保持随手加空格的习惯。 - -## 标点符号 - -### 不重复使用标点符号 - -正确： - -> 德国队竟然战胜了巴西队！ - -> 她竟然对你说“喵”？！ - -错误： - -> 德国队竟然战胜了巴西队！！ - -> 德国队竟然战胜了巴西队！！！！！！！！ - -> 她竟然对你说「喵」？？！！ - -> 她竟然对你说「喵」？！？！？？！！ - -## 全角和半角 - -不明白什么是全角（全形）与半角（半形）符号？请查看维基百科词条『[全角和半角](http://zh.wikipedia.org/wiki/%E5%85%A8%E5%BD%A2%E5%92%8C%E5%8D%8A%E5%BD%A2)』。 - -### 使用全角中文标点 - -正确： - -> 嗨！你知道嘛？今天前台的小妹跟我说“喵”了哎！ - -> 核磁共振成像（NMRI）是什么原理都不知道？JFGI！ - -错误： - -> 嗨! 你知道嘛? 今天前台的小妹跟我说 "喵" 了哎! - -> 嗨!你知道嘛?今天前台的小妹跟我说"喵"了哎! - -> 核磁共振成像 (NMRI) 是什么原理都不知道? JFGI! - -> 核磁共振成像(NMRI)是什么原理都不知道?JFGI! - -### 数字使用半角字符 - -正确： - -> 这件蛋糕只卖 1000 元。 - -错误： - -> 这件蛋糕只卖 １０００ 元。 - -例外：在设计稿、宣传海报中如出现极少量数字的情形时，为方便文字对齐，是可以使用全角数字的。 - -### 遇到完整的英文整句、特殊名词，其內容使用半角标点 - -正确： - -> 乔布斯那句话是怎么说的？“Stay hungry, stay foolish.” - -> 推荐你阅读《Hackers & Painters: Big Ideas from the Computer Age》，非常的有趣。 - -错误： - -> 乔布斯那句话是怎么说的？「Stay hungry，stay foolish。」 - -> 推荐你阅读《Hackers＆Painters：Big Ideas from the Computer Age》，非常的有趣。 - -## 名词 - -### 专有名词使用正确的大小写 - -大小写相关用法原属于英文书写范畴，不属于本 wiki 讨论內容，在这里只对部分易错用法进行简述。 - -正确： - -> 使用 GitHub 登录 - -> 我们的客户有 GitHub、Foursquare、Microsoft Corporation、Google、Facebook, Inc.。 - -错误： - -> 使用 github 登录 - -> 使用 GITHUB 登录 - -> 使用 Github 登录 - -> 使用 gitHub 登录 - -> 使用 gｲんĤЦ8 登录 - -> 我们的客户有 github、foursquare、microsoft corporation、google、facebook, inc.。 - -> 我们的客户有 GITHUB、FOURSQUARE、MICROSOFT CORPORATION、GOOGLE、FACEBOOK, INC.。 - -> 我们的客户有 Github、FourSquare、MicroSoft Corporation、Google、FaceBook, Inc.。 - -> 我们的客户有 gitHub、fourSquare、microSoft Corporation、google、faceBook, Inc.。 - -> 我们的客户有 gｲんĤЦ8、ｷouЯƧquﾑгє、๓เςг๏ร๏Ŧt ς๏гק๏гคtเ๏ภn、900913、ƒ4ᄃëв๏๏к, IПᄃ.。 - -注意：当网页中需要配合整体视觉风格而出现全部大写／小写的情形，HTML 中请使用标准的大小写规范进行书写；并通过 `text-transform: uppercase;`／`text-transform: lowercase;` 对表现形式进行定义。 - -### 不要使用不地道的缩写 - -正确： - -> 我们需要一位熟悉 JavaScript、HTML5，至少理解一种框架（如 Backbone.js、AngularJS、React 等）的前端开发者。 - -错误： - -> 我们需要一位熟悉 Js、h5，至少理解一种框架（如 backbone、angular、RJS 等）的 FED。 - -## 争议 - -以下用法略带有个人色彩，既：无论是否遵循下述规则，从语法的角度来讲都是**正确**的。 - -### 链接之间增加空格 - -用法： - -> 请 [提交一个 issue](#) 并分配给相关同事。 - -> 访问我们网站的最新动态，请 [点击这里](#) 进行订阅！ - -对比用法： - -> 请[提交一个 issue](#) 并分配给相关同事。 - -> 访问我们网站的最新动态，请[点击这里](#)进行订阅！ - -### 简体中文不要使用直角引号 - -不管中英文，如果没有特殊要求，**不要用直角引号**。 - -## 工具 - -仓库 | 语言 ---- | --- -[vinta/paranoid-auto-spacing](https://github.com/vinta/paranoid-auto-spacing) | JavaScript -[huei90/pangu.node](https://github.com/huei90/pangu.node) | Node.js -[huacnlee/auto-correct](https://github.com/huacnlee/auto-correct) | Ruby -[sparanoid/space-lover](https://github.com/sparanoid/space-lover) | PHP (WordPress) -[nauxliu/auto-correct](https://github.com/NauxLiu/auto-correct) | PHP -[hotoo/pangu.vim](https://github.com/hotoo/pangu.vim) | Vim -[sparanoid/grunt-auto-spacing](https://github.com/sparanoid/grunt-auto-spacing) | Node.js (Grunt) -[hjiang/scripts/add-space-between-latin-and-cjk](https://github.com/hjiang/scripts/blob/master/add-space-between-latin-and-cjk) | Python - -## 谁在这样做？ - -网站 | 文案 | UGC ---- | --- | --- -[Apple 中国](http://www.apple.com/cn/) | Yes | N/A -[Apple 香港](http://www.apple.com/hk/) | Yes | N/A -[Apple 台湾](http://www.apple.com/tw/) | Yes | N/A -[Microsoft 中国](http://www.microsoft.com/zh-cn/) | Yes | N/A -[Microsoft 香港](http://www.microsoft.com/zh-hk/) | Yes | N/A -[Microsoft 台湾](http://www.microsoft.com/zh-tw/) | Yes | N/A -[LeanCloud](https://leancloud.cn/) | Yes | N/A -[知乎](https://www.zhihu.com/) | Yes | 部分用户达成 -[V2EX](https://www.v2ex.com/) | Yes | Yes -[SegmentFault](https://segmentfault.com/) | Yes | 部分用户达成 -[Apple4us](http://apple4us.com/) | Yes | N/A -[豌豆荚](https://www.wandoujia.com/) | Yes | N/A -[Ruby China](https://ruby-china.org/) | Yes | 标题达成 -[PHPHub](https://phphub.org/) | Yes | 标题达成 - -## 参考文献 - -- [Guidelines for Using Capital Letters](http://grammar.about.com/od/punctuationandmechanics/a/Guidelines-For-Using-Capital-Letters.htm) -- [Letter case - Wikipedia](http://en.wikipedia.org/wiki/Letter_case) -- [Punctuation - Oxford Dictionaries](http://www.oxforddictionaries.com/words/punctuation) -- [Punctuation - The Purdue OWL](https://owl.english.purdue.edu/owl/section/1/6/) -- [How to Use English Punctuation Corrently - wikiHow](http://www.wikihow.com/Use-English-Punctuation-Correctly) -- [格式 - openSUSE](https://zh.opensuse.org/index.php?title=Help:%E6%A0%BC%E5%BC%8F) -- [全角和半角 - 维基百科](http://zh.wikipedia.org/wiki/%E5%85%A8%E5%BD%A2%E5%92%8C%E5%8D%8A%E5%BD%A2) -- [引号 - 维基百科](http://zh.wikipedia.org/wiki/%E5%BC%95%E8%99%9F) -- [疑问惊叹号 - 维基百科](http://zh.wikipedia.org/wiki/%E7%96%91%E5%95%8F%E9%A9%9A%E5%98%86%E8%99%9F) - -## CopyRight - -[中文文案排版指北](https://github.com/sparanoid/chinese-copywriting-guidelines) diff --git a/选题模板.txt b/选题模板.txt deleted file mode 100644 index a7cd92e614..0000000000 --- a/选题模板.txt +++ /dev/null @@ -1,43 +0,0 @@ -选题标题格式: - - 原文日期 标题.md - -正文内容: - - 标题 - ======= - - ### 子一级标题 - - 正文 - - #### 子二级标题 - - 正文内容 - - ![](图片地址) - - ### 子一级标题 - - 正文内容 ： I have a [dream][1]。 - - -------------------------------------------------------------------------------- - - via: 原文地址 - - 作者：[作者名][a] - 译者：[译者ID](https://github.com/译者ID) - 校对：[校对者ID](https://github.com/校对者ID) - - 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - - [a]: 作者介绍地址 - [1]: 引文链接地址 - -说明: -1. 标题层级很多时从 “##” 开始 -2. 引文链接地址在下方集中写 -3. 因为 Windows 系统文件名有限制，所以文章名不要有特殊符号，如 `\/:*"<>|`，同时也不推荐全大写，或者其它不利阅读的格式 -4. 正文格式参照中文排版指北(https://github.com/LCTT/TranslateProject/blob/master/%E4%B8%AD%E6%96%87%E6%8E%92%E7%89%88%E6%8C%87%E5%8C%97.md) -5. 我们使用的 markdown 语法和 github 一致，具体语法可参见 https://github.com/guodongxiaren/README 。而实际中使用的都是基本语法，比如链接、包含图片、标题、列表、字体控制和代码高亮。 -6. 选题的内容分为两类： 干货和湿货。干货就是技术文章，比如针对某种技术、工具的介绍、讲解和讨论。湿货则是和技术、开发、计算机文化有关的文章。选题时主要就是根据这两条来选择文章，文章需要对大家有益处，篇幅不宜太短，可以是系列文章，也可以是长篇大论，但是文章要有内容，不能有严重的错误，最好不要选择已经有翻译的原文。