forgejo-federation/modules/queue/queue_channel.go
flynnnnnnnnnn e81ccc406b
Implement FSFE REUSE for golang files (#21840)
Change all license headers to comply with REUSE specification.

Fix #16132

Co-authored-by: flynnnnnnnnnn <flynnnnnnnnnn@github>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>
2022-11-27 18:20:29 +00:00

183 lines
4.8 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package queue
import (
"context"
"fmt"
"runtime/pprof"
"sync/atomic"
"time"
"code.gitea.io/gitea/modules/log"
)
// ChannelQueueType is the type for channel queue
const ChannelQueueType Type = "channel"
// ChannelQueueConfiguration is the configuration for a ChannelQueue
type ChannelQueueConfiguration struct {
WorkerPoolConfiguration
Workers int
}
// ChannelQueue implements Queue
//
// A channel queue is not persistable and does not shutdown or terminate cleanly
// It is basically a very thin wrapper around a WorkerPool
type ChannelQueue struct {
*WorkerPool
shutdownCtx context.Context
shutdownCtxCancel context.CancelFunc
terminateCtx context.Context
terminateCtxCancel context.CancelFunc
exemplar interface{}
workers int
name string
}
// NewChannelQueue creates a memory channel queue
func NewChannelQueue(handle HandlerFunc, cfg, exemplar interface{}) (Queue, error) {
configInterface, err := toConfig(ChannelQueueConfiguration{}, cfg)
if err != nil {
return nil, err
}
config := configInterface.(ChannelQueueConfiguration)
if config.BatchLength == 0 {
config.BatchLength = 1
}
terminateCtx, terminateCtxCancel := context.WithCancel(context.Background())
shutdownCtx, shutdownCtxCancel := context.WithCancel(terminateCtx)
queue := &ChannelQueue{
shutdownCtx: shutdownCtx,
shutdownCtxCancel: shutdownCtxCancel,
terminateCtx: terminateCtx,
terminateCtxCancel: terminateCtxCancel,
exemplar: exemplar,
workers: config.Workers,
name: config.Name,
}
queue.WorkerPool = NewWorkerPool(func(data ...Data) []Data {
unhandled := handle(data...)
if len(unhandled) > 0 {
// We can only pushback to the channel if we're paused.
if queue.IsPaused() {
atomic.AddInt64(&queue.numInQueue, int64(len(unhandled)))
go func() {
for _, datum := range data {
queue.dataChan <- datum
}
}()
return nil
}
}
return unhandled
}, config.WorkerPoolConfiguration)
queue.qid = GetManager().Add(queue, ChannelQueueType, config, exemplar)
return queue, nil
}
// Run starts to run the queue
func (q *ChannelQueue) Run(atShutdown, atTerminate func(func())) {
pprof.SetGoroutineLabels(q.baseCtx)
atShutdown(q.Shutdown)
atTerminate(q.Terminate)
log.Debug("ChannelQueue: %s Starting", q.name)
_ = q.AddWorkers(q.workers, 0)
}
// Push will push data into the queue
func (q *ChannelQueue) Push(data Data) error {
if !assignableTo(data, q.exemplar) {
return fmt.Errorf("unable to assign data: %v to same type as exemplar: %v in queue: %s", data, q.exemplar, q.name)
}
q.WorkerPool.Push(data)
return nil
}
// Flush flushes the channel with a timeout - the Flush worker will be registered as a flush worker with the manager
func (q *ChannelQueue) Flush(timeout time.Duration) error {
if q.IsPaused() {
return nil
}
ctx, cancel := q.commonRegisterWorkers(1, timeout, true)
defer cancel()
return q.FlushWithContext(ctx)
}
// FlushWithContext is very similar to CleanUp but it will return as soon as the dataChan is empty
func (q *ChannelQueue) FlushWithContext(ctx context.Context) error {
log.Trace("ChannelQueue: %d Flush", q.qid)
paused, _ := q.IsPausedIsResumed()
for {
select {
case <-paused:
return nil
case data, ok := <-q.dataChan:
if !ok {
return nil
}
if unhandled := q.handle(data); unhandled != nil {
log.Error("Unhandled Data whilst flushing queue %d", q.qid)
}
atomic.AddInt64(&q.numInQueue, -1)
case <-q.baseCtx.Done():
return q.baseCtx.Err()
case <-ctx.Done():
return ctx.Err()
default:
return nil
}
}
}
// Shutdown processing from this queue
func (q *ChannelQueue) Shutdown() {
q.lock.Lock()
defer q.lock.Unlock()
select {
case <-q.shutdownCtx.Done():
log.Trace("ChannelQueue: %s Already Shutting down", q.name)
return
default:
}
log.Trace("ChannelQueue: %s Shutting down", q.name)
go func() {
log.Trace("ChannelQueue: %s Flushing", q.name)
// We can't use Cleanup here because that will close the channel
if err := q.FlushWithContext(q.terminateCtx); err != nil {
log.Warn("ChannelQueue: %s Terminated before completed flushing", q.name)
return
}
log.Debug("ChannelQueue: %s Flushed", q.name)
}()
q.shutdownCtxCancel()
log.Debug("ChannelQueue: %s Shutdown", q.name)
}
// Terminate this queue and close the queue
func (q *ChannelQueue) Terminate() {
log.Trace("ChannelQueue: %s Terminating", q.name)
q.Shutdown()
select {
case <-q.terminateCtx.Done():
return
default:
}
q.terminateCtxCancel()
q.baseCtxFinished()
log.Debug("ChannelQueue: %s Terminated", q.name)
}
// Name returns the name of this queue
func (q *ChannelQueue) Name() string {
return q.name
}
func init() {
queuesMap[ChannelQueueType] = NewChannelQueue
}