From f753d6d7c3c9c92b4e900d493ef0930264d89fd2 Mon Sep 17 00:00:00 2001 From: DarkSun Date: Tue, 17 Sep 2019 13:11:11 +0800 Subject: [PATCH] =?UTF-8?q?=E9=80=89=E9=A2=98:=2020170115=20Magic=20GOPATH?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit sources/tech/20170115 Magic GOPATH.md --- sources/tech/20170115 Magic GOPATH.md | 119 ++++++++++++++++++++++++++ 1 file changed, 119 insertions(+) create mode 100644 sources/tech/20170115 Magic GOPATH.md diff --git a/sources/tech/20170115 Magic GOPATH.md b/sources/tech/20170115 Magic GOPATH.md new file mode 100644 index 0000000000..1d4cd16e24 --- /dev/null +++ b/sources/tech/20170115 Magic GOPATH.md @@ -0,0 +1,119 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Magic GOPATH) +[#]: via: (https://www.jtolio.com/2017/01/magic-gopath) +[#]: author: (jtolio.com https://www.jtolio.com/) + +Magic GOPATH +====== + +_**Update:** With the advent of Go 1.11 and [Go modules][1], this whole post is now useless. Unset your GOPATH entirely and switch to Go modules today!_ + +Maybe someday I’ll start writing about things besides Go again. + +Go requires that you set an environment variable for your workspace called your `GOPATH`. The `GOPATH` is one of the most confusing aspects of Go to newcomers and even relatively seasoned developers alike. It’s not immediately clear what would be better, but finding a good `GOPATH` value has implications for your source code repository layout, how many separate projects you have on your computer, how default project installation instructions work (via `go get`), and even how you interoperate with other projects and libraries. + +It’s taken until Go 1.8 to decide to [set a default][2] and that small change was one of [the most talked about code reviews][3] for the 1.8 release cycle. + +After [writing about GOPATH himself][4], [Dave Cheney][5] [asked me][6] to write a blog post about what I do. + +### My proposal + +I set my `GOPATH` to always be the current working directory, unless a parent directory is clearly the `GOPATH`. + +Here’s the relevant part of my `.bashrc`: + +``` +# bash command to output calculated GOPATH. +calc_gopath() { + local dir="$PWD" + + # we're going to walk up from the current directory to the root + while true; do + + # if there's a '.gopath' file, use its contents as the GOPATH relative to + # the directory containing it. + if [ -f "$dir/.gopath" ]; then + ( cd "$dir"; + # allow us to squash this behavior for cases we want to use vgo + if [ "$(cat .gopath)" != "" ]; then + cd "$(cat .gopath)"; + echo "$PWD"; + fi; ) + return + fi + + # if there's a 'src' directory, the parent of that directory is now the + # GOPATH + if [ -d "$dir/src" ]; then + echo "$dir" + return + fi + + # we can't go further, so bail. we'll make the original PWD the GOPATH. + if [ "$dir" == "/" ]; then + echo "$PWD" + return + fi + + # now we'll consider the parent directory + dir="$(dirname "$dir")" + done +} + +my_prompt_command() { + export GOPATH="$(calc_gopath)" + + # you can have other neat things in here. I also set my PS1 based on git + # state +} + +case "$TERM" in +xterm*|rxvt*) + # Bash provides an environment variable called PROMPT_COMMAND. The contents + # of this variable are executed as a regular Bash command just before Bash + # displays a prompt. Let's only set it if we're in some kind of graphical + # terminal I guess. + PROMPT_COMMAND=my_prompt_command + ;; +*) + ;; +esac +``` + +The benefits are fantastic. If you want to quickly `go get` something and not have it clutter up your workspace, you can do something like: + +``` +cd $(mktemp -d) && go get github.com/the/thing +``` + +On the other hand, if you’re jumping between multiple projects (whether or not they have the full workspace checked in or are just library packages), the `GOPATH` is set accurately. + +More flexibly, if you have a tree where some parent directory is outside of the `GOPATH` but you want to set the `GOPATH` anyways, you can create a `.gopath` file and it will automatically set your `GOPATH` correctly any time your shell is inside that directory. + +The whole thing is super nice. I kinda can’t imagine doing something else anymore. + +### Fin. + +-------------------------------------------------------------------------------- + +via: https://www.jtolio.com/2017/01/magic-gopath + +作者:[jtolio.com][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.jtolio.com/ +[b]: https://github.com/lujun9972 +[1]: https://golang.org/cmd/go/#hdr-Modules__module_versions__and_more +[2]: https://rakyll.org/default-gopath/ +[3]: https://go-review.googlesource.com/32019/ +[4]: https://dave.cheney.net/2016/12/20/thinking-about-gopath +[5]: https://dave.cheney.net/ +[6]: https://twitter.com/davecheney/status/811334240247812097