Files
memgraph/src/coordination/coordinator_handlers.cpp
2024-02-28 09:57:00 +00:00

230 lines
10 KiB
C++

// Copyright 2024 Memgraph Ltd.
//
// Use of this software is governed by the Business Source License
// included in the file licenses/BSL.txt; by using this file, you agree to be bound by the terms of the Business Source
// License, and you may not use this file except in compliance with the Business Source License.
//
// As of the Change Date specified in that file, in accordance with
// the Business Source License, use of this software will be governed
// by the Apache License, Version 2.0, included in the file
// licenses/APL.txt.
#ifdef MG_ENTERPRISE
#include "coordination/coordinator_handlers.hpp"
#include <range/v3/view.hpp>
#include "coordination/coordinator_rpc.hpp"
#include "coordination/include/coordination/coordinator_server.hpp"
#include "replication/state.hpp"
namespace memgraph::dbms {
void CoordinatorHandlers::Register(memgraph::coordination::CoordinatorServer &server,
replication::ReplicationHandler &replication_handler) {
server.Register<coordination::PromoteReplicaToMainRpc>(
[&](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received PromoteReplicaToMainRpc");
CoordinatorHandlers::PromoteReplicaToMainHandler(replication_handler, req_reader, res_builder);
});
server.Register<coordination::DemoteMainToReplicaRpc>(
[&replication_handler](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received DemoteMainToReplicaRpc from coordinator server");
CoordinatorHandlers::DemoteMainToReplicaHandler(replication_handler, req_reader, res_builder);
});
server.Register<replication_coordination_glue::SwapMainUUIDRpc>(
[&replication_handler](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received SwapMainUUIDRPC on coordinator server");
CoordinatorHandlers::SwapMainUUIDHandler(replication_handler, req_reader, res_builder);
});
server.Register<coordination::UnregisterReplicaRpc>(
[&replication_handler](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received UnregisterReplicaRpc on coordinator server");
CoordinatorHandlers::UnregisterReplicaHandler(replication_handler, req_reader, res_builder);
});
server.Register<coordination::EnableWritingOnMainRpc>(
[&replication_handler](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received EnableWritingOnMainRpc on coordinator server");
CoordinatorHandlers::EnableWritingOnMainHandler(replication_handler, req_reader, res_builder);
});
server.Register<coordination::GetInstanceUUIDRpc>(
[&replication_handler](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received GetInstanceUUIDRpc on coordinator server");
CoordinatorHandlers::GetInstanceUUIDHandler(replication_handler, req_reader, res_builder);
});
server.Register<coordination::GetDatabaseHistoriesRpc>(
[&replication_handler](slk::Reader *req_reader, slk::Builder *res_builder) -> void {
spdlog::info("Received GetDatabasesHistoryRpc on coordinator server");
CoordinatorHandlers::GetDatabaseHistoriesHandler(replication_handler, req_reader, res_builder);
});
}
void CoordinatorHandlers::GetDatabaseHistoriesHandler(replication::ReplicationHandler &replication_handler,
slk::Reader * /*req_reader*/, slk::Builder *res_builder) {
slk::Save(coordination::GetDatabaseHistoriesRes{replication_handler.GetDatabasesHistories()}, res_builder);
}
void CoordinatorHandlers::SwapMainUUIDHandler(replication::ReplicationHandler &replication_handler,
slk::Reader *req_reader, slk::Builder *res_builder) {
if (!replication_handler.IsReplica()) {
spdlog::error("Setting main uuid must be performed on replica.");
slk::Save(replication_coordination_glue::SwapMainUUIDRes{false}, res_builder);
return;
}
replication_coordination_glue::SwapMainUUIDReq req;
slk::Load(&req, req_reader);
spdlog::info(fmt::format("Set replica data UUID to main uuid {}", std::string(req.uuid)));
std::get<memgraph::replication::RoleReplicaData>(replication_handler.GetReplState().ReplicationData()).uuid_ =
req.uuid;
slk::Save(replication_coordination_glue::SwapMainUUIDRes{true}, res_builder);
}
void CoordinatorHandlers::DemoteMainToReplicaHandler(replication::ReplicationHandler &replication_handler,
slk::Reader *req_reader, slk::Builder *res_builder) {
spdlog::info("Executing DemoteMainToReplicaHandler");
coordination::DemoteMainToReplicaReq req;
slk::Load(&req, req_reader);
const replication::ReplicationServerConfig clients_config{
.ip_address = req.replication_client_info.replication_ip_address,
.port = req.replication_client_info.replication_port};
if (!replication_handler.SetReplicationRoleReplica(clients_config, std::nullopt)) {
spdlog::error("Demoting main to replica failed!");
slk::Save(coordination::DemoteMainToReplicaRes{false}, res_builder);
return;
}
slk::Save(coordination::DemoteMainToReplicaRes{true}, res_builder);
}
void CoordinatorHandlers::GetInstanceUUIDHandler(replication::ReplicationHandler &replication_handler,
slk::Reader * /*req_reader*/, slk::Builder *res_builder) {
spdlog::info("Executing GetInstanceUUIDHandler");
slk::Save(coordination::GetInstanceUUIDRes{replication_handler.GetReplicaUUID()}, res_builder);
}
void CoordinatorHandlers::PromoteReplicaToMainHandler(replication::ReplicationHandler &replication_handler,
slk::Reader *req_reader, slk::Builder *res_builder) {
if (!replication_handler.IsReplica()) {
spdlog::error("Failover must be performed on replica!");
slk::Save(coordination::PromoteReplicaToMainRes{false}, res_builder);
return;
}
coordination::PromoteReplicaToMainReq req;
slk::Load(&req, req_reader);
// This can fail because of disk. If it does, the cluster state could get inconsistent.
// We don't handle disk issues.
if (const bool success = replication_handler.DoReplicaToMainPromotion(req.main_uuid_); !success) {
spdlog::error("Promoting replica to main failed!");
slk::Save(coordination::PromoteReplicaToMainRes{false}, res_builder);
return;
}
auto const converter = [](const auto &repl_info_config) {
return replication::ReplicationClientConfig{
.name = repl_info_config.instance_name,
.mode = repl_info_config.replication_mode,
.ip_address = repl_info_config.replication_ip_address,
.port = repl_info_config.replication_port,
};
};
// registering replicas
for (auto const &config : req.replication_clients_info | ranges::views::transform(converter)) {
auto instance_client = replication_handler.RegisterReplica(config);
if (instance_client.HasError()) {
using enum memgraph::replication::RegisterReplicaError;
switch (instance_client.GetError()) {
// Can't happen, checked on the coordinator side
case memgraph::query::RegisterReplicaError::NAME_EXISTS:
spdlog::error("Replica with the same name already exists!");
slk::Save(coordination::PromoteReplicaToMainRes{false}, res_builder);
return;
// Can't happen, checked on the coordinator side
case memgraph::query::RegisterReplicaError::ENDPOINT_EXISTS:
spdlog::error("Replica with the same endpoint already exists!");
slk::Save(coordination::PromoteReplicaToMainRes{false}, res_builder);
return;
// We don't handle disk issues
case memgraph::query::RegisterReplicaError::COULD_NOT_BE_PERSISTED:
spdlog::error("Registered replica could not be persisted!");
slk::Save(coordination::PromoteReplicaToMainRes{false}, res_builder);
return;
case memgraph::query::RegisterReplicaError::ERROR_ACCEPTING_MAIN:
spdlog::error("Replica didn't accept change of main!");
slk::Save(coordination::PromoteReplicaToMainRes{false}, res_builder);
return;
case memgraph::query::RegisterReplicaError::CONNECTION_FAILED:
// Connection failure is not a fatal error
break;
}
}
}
spdlog::info("Promote replica to main was success {}", std::string(req.main_uuid_));
slk::Save(coordination::PromoteReplicaToMainRes{true}, res_builder);
}
void CoordinatorHandlers::UnregisterReplicaHandler(replication::ReplicationHandler &replication_handler,
slk::Reader *req_reader, slk::Builder *res_builder) {
if (!replication_handler.IsMain()) {
spdlog::error("Unregistering replica must be performed on main.");
slk::Save(coordination::UnregisterReplicaRes{false}, res_builder);
return;
}
coordination::UnregisterReplicaReq req;
slk::Load(&req, req_reader);
auto res = replication_handler.UnregisterReplica(req.instance_name);
switch (res) {
using enum memgraph::query::UnregisterReplicaResult;
case SUCCESS:
slk::Save(coordination::UnregisterReplicaRes{true}, res_builder);
break;
case NOT_MAIN:
spdlog::error("Unregistering replica must be performed on main.");
slk::Save(coordination::UnregisterReplicaRes{false}, res_builder);
break;
case CAN_NOT_UNREGISTER:
spdlog::error("Could not unregister replica.");
slk::Save(coordination::UnregisterReplicaRes{false}, res_builder);
break;
case COULD_NOT_BE_PERSISTED:
spdlog::error("Could not persist replica unregistration.");
slk::Save(coordination::UnregisterReplicaRes{false}, res_builder);
break;
}
}
void CoordinatorHandlers::EnableWritingOnMainHandler(replication::ReplicationHandler &replication_handler,
slk::Reader * /*req_reader*/, slk::Builder *res_builder) {
if (!replication_handler.IsMain()) {
spdlog::error("Enable writing on main must be performed on main!");
slk::Save(coordination::EnableWritingOnMainRes{false}, res_builder);
return;
}
if (!replication_handler.GetReplState().EnableWritingOnMain()) {
spdlog::error("Enabling writing on main failed!");
slk::Save(coordination::EnableWritingOnMainRes{false}, res_builder);
return;
}
slk::Save(coordination::EnableWritingOnMainRes{true}, res_builder);
}
} // namespace memgraph::dbms
#endif