itdoxy-lab/modules/queue/base_channel.go

124 lines
2.2 KiB
Go

// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package queue
import (
"context"
"errors"
"sync"
"time"
"code.gitea.io/gitea/modules/container"
)
var errChannelClosed = errors.New("channel is closed")
type baseChannel struct {
c chan []byte
set container.Set[string]
mu sync.Mutex
isUnique bool
}
var _ baseQueue = (*baseChannel)(nil)
func newBaseChannelGeneric(cfg *BaseConfig, unique bool) (baseQueue, error) {
q := &baseChannel{c: make(chan []byte, cfg.Length), isUnique: unique}
if unique {
q.set = container.Set[string]{}
}
return q, nil
}
func newBaseChannelSimple(cfg *BaseConfig) (baseQueue, error) {
return newBaseChannelGeneric(cfg, false)
}
func newBaseChannelUnique(cfg *BaseConfig) (baseQueue, error) {
return newBaseChannelGeneric(cfg, true)
}
func (q *baseChannel) PushItem(ctx context.Context, data []byte) error {
if q.c == nil {
return errChannelClosed
}
if q.isUnique {
q.mu.Lock()
has := q.set.Contains(string(data))
q.mu.Unlock()
if has {
return ErrAlreadyInQueue
}
}
select {
case q.c <- data:
if q.isUnique {
q.mu.Lock()
q.set.Add(string(data))
q.mu.Unlock()
}
return nil
case <-time.After(pushBlockTime):
return context.DeadlineExceeded
case <-ctx.Done():
return ctx.Err()
}
}
func (q *baseChannel) PopItem(ctx context.Context) ([]byte, error) {
select {
case data, ok := <-q.c:
if !ok {
return nil, errChannelClosed
}
q.mu.Lock()
q.set.Remove(string(data))
q.mu.Unlock()
return data, nil
case <-ctx.Done():
return nil, ctx.Err()
}
}
func (q *baseChannel) HasItem(ctx context.Context, data []byte) (bool, error) {
q.mu.Lock()
defer q.mu.Unlock()
return q.set.Contains(string(data)), nil
}
func (q *baseChannel) Len(ctx context.Context) (int, error) {
q.mu.Lock()
defer q.mu.Unlock()
if q.c == nil {
return 0, errChannelClosed
}
return len(q.c), nil
}
func (q *baseChannel) Close() error {
q.mu.Lock()
defer q.mu.Unlock()
close(q.c)
q.set = container.Set[string]{}
return nil
}
func (q *baseChannel) RemoveAll(ctx context.Context) error {
q.mu.Lock()
defer q.mu.Unlock()
for q.c != nil && len(q.c) > 0 {
<-q.c
}
return nil
}