forgejo/modules/log/event_writer_base.go
wxiaoguang 18f26cfbf7
Improve queue and logger context (#24924)
Before there was a "graceful function": RunWithShutdownFns, it's mainly
for some modules which doesn't support context.

The old queue system doesn't work well with context, so the old queues
need it.

After the queue refactoring, the new queue works with context well, so,
use Golang context as much as possible, the `RunWithShutdownFns` could
be removed (replaced by RunWithCancel for context cancel mechanism), the
related code could be simplified.

This PR also fixes some legacy queue-init problems, eg:

* typo : archiver: "unable to create codes indexer queue" => "unable to
create repo-archive queue"
* no nil check for failed queues, which causes unfriendly panic

After this PR, many goroutines could have better display name:

![image](https://github.com/go-gitea/gitea/assets/2114189/701b2a9b-8065-4137-aeaa-0bda2b34604a)

![image](https://github.com/go-gitea/gitea/assets/2114189/f1d5f50f-0534-40f0-b0be-f2c9daa5fe92)
2023-05-26 07:31:55 +00:00

169 lines
4 KiB
Go

// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package log
import (
"context"
"fmt"
"io"
"regexp"
"runtime/pprof"
"time"
)
// EventWriterBase is the base interface for most event writers
// It provides default implementations for most methods
type EventWriterBase interface {
Base() *EventWriterBaseImpl
GetWriterType() string
GetWriterName() string
GetLevel() Level
Run(ctx context.Context)
}
type EventWriterBaseImpl struct {
writerType string
Name string
Mode *WriterMode
Queue chan *EventFormatted
FormatMessage EventFormatter // format the Event to a message and write it to output
OutputWriteCloser io.WriteCloser // it will be closed when the event writer is stopped
GetPauseChan func() chan struct{}
shared bool
stopped chan struct{}
}
var _ EventWriterBase = (*EventWriterBaseImpl)(nil)
func (b *EventWriterBaseImpl) Base() *EventWriterBaseImpl {
return b
}
func (b *EventWriterBaseImpl) GetWriterType() string {
return b.writerType
}
func (b *EventWriterBaseImpl) GetWriterName() string {
return b.Name
}
func (b *EventWriterBaseImpl) GetLevel() Level {
return b.Mode.Level
}
// Run is the default implementation for EventWriter.Run
func (b *EventWriterBaseImpl) Run(ctx context.Context) {
defer b.OutputWriteCloser.Close()
var exprRegexp *regexp.Regexp
if b.Mode.Expression != "" {
var err error
if exprRegexp, err = regexp.Compile(b.Mode.Expression); err != nil {
FallbackErrorf("unable to compile expression %q for writer %q: %v", b.Mode.Expression, b.Name, err)
}
}
for {
if b.GetPauseChan != nil {
pause := b.GetPauseChan()
if pause != nil {
select {
case <-pause:
case <-ctx.Done():
return
}
}
}
select {
case <-ctx.Done():
return
case event, ok := <-b.Queue:
if !ok {
return
}
if exprRegexp != nil {
fileLineCaller := fmt.Sprintf("%s:%d:%s", event.Origin.Filename, event.Origin.Line, event.Origin.Caller)
matched := exprRegexp.Match([]byte(fileLineCaller)) || exprRegexp.Match([]byte(event.Origin.MsgSimpleText))
if !matched {
continue
}
}
var err error
switch msg := event.Msg.(type) {
case string:
_, err = b.OutputWriteCloser.Write([]byte(msg))
case []byte:
_, err = b.OutputWriteCloser.Write(msg)
case io.WriterTo:
_, err = msg.WriteTo(b.OutputWriteCloser)
default:
_, err = b.OutputWriteCloser.Write([]byte(fmt.Sprint(msg)))
}
if err != nil {
FallbackErrorf("unable to write log message of %q (%v): %v", b.Name, err, event.Msg)
}
}
}
}
func NewEventWriterBase(name, writerType string, mode WriterMode) *EventWriterBaseImpl {
if mode.BufferLen == 0 {
mode.BufferLen = 1000
}
if mode.Level == UNDEFINED {
mode.Level = INFO
}
if mode.StacktraceLevel == UNDEFINED {
mode.StacktraceLevel = NONE
}
b := &EventWriterBaseImpl{
writerType: writerType,
Name: name,
Mode: &mode,
Queue: make(chan *EventFormatted, mode.BufferLen),
GetPauseChan: GetManager().GetPauseChan, // by default, use the global pause channel
FormatMessage: EventFormatTextMessage,
}
return b
}
// eventWriterStartGo use "go" to start an event worker's Run method
func eventWriterStartGo(ctx context.Context, w EventWriter, shared bool) {
if w.Base().stopped != nil {
return // already started
}
w.Base().shared = shared
w.Base().stopped = make(chan struct{})
ctxDesc := "Logger: EventWriter: " + w.GetWriterName()
if shared {
ctxDesc = "Logger: EventWriter (shared): " + w.GetWriterName()
}
writerCtx, writerCancel := newContext(ctx, ctxDesc)
go func() {
defer writerCancel()
defer close(w.Base().stopped)
pprof.SetGoroutineLabels(writerCtx)
w.Run(writerCtx)
}()
}
// eventWriterStopWait stops an event writer and waits for it to finish flushing (with a timeout)
func eventWriterStopWait(w EventWriter) {
close(w.Base().Queue)
select {
case <-w.Base().stopped:
case <-time.After(2 * time.Second):
FallbackErrorf("unable to stop log writer %q in time, skip", w.GetWriterName())
}
}