| // Copyright 2019 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package protocol |
| |
| import ( |
| "bytes" |
| "context" |
| "sync" |
| |
| "golang.org/x/tools/internal/event" |
| "golang.org/x/tools/internal/event/core" |
| "golang.org/x/tools/internal/event/export" |
| "golang.org/x/tools/internal/event/label" |
| "golang.org/x/tools/internal/xcontext" |
| ) |
| |
| type contextKey int |
| |
| const ( |
| clientKey = contextKey(iota) |
| ) |
| |
| func WithClient(ctx context.Context, client Client) context.Context { |
| return context.WithValue(ctx, clientKey, client) |
| } |
| |
| func LogEvent(ctx context.Context, ev core.Event, lm label.Map, mt MessageType) context.Context { |
| client, ok := ctx.Value(clientKey).(Client) |
| if !ok { |
| return ctx |
| } |
| buf := &bytes.Buffer{} |
| p := export.Printer{} |
| p.WriteEvent(buf, ev, lm) |
| msg := &LogMessageParams{Type: mt, Message: buf.String()} |
| // Handle messages generated via event.Error, which won't have a level Label. |
| if event.IsError(ev) { |
| msg.Type = Error |
| } |
| |
| // The background goroutine lives forever once started, |
| // and ensures log messages are sent in order (#61216). |
| startLogSenderOnce.Do(func() { |
| go func() { |
| for f := range logQueue { |
| f() |
| } |
| }() |
| }) |
| |
| // Add the log item to a queue, rather than sending a |
| // window/logMessage request to the client synchronously, |
| // which would slow down this thread. |
| ctx2 := xcontext.Detach(ctx) |
| logQueue <- func() { client.LogMessage(ctx2, msg) } |
| |
| return ctx |
| } |
| |
| var ( |
| startLogSenderOnce sync.Once |
| logQueue = make(chan func(), 100) // big enough for a large transient burst |
| ) |