69 lines
948 B
Go
69 lines
948 B
Go
// Package idle helps to gracefully shutdown idle servers
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package idle
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import (
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"sync/atomic"
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"time"
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)
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type Idler interface {
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Enter()
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Exit()
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Wait()
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Tick()
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Chan() <-chan struct{}
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}
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type idler struct {
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lastTick atomic.Pointer[time.Time]
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c chan struct{}
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active atomic.Int64
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}
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func (i *idler) Enter() {
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i.active.Add(1)
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}
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func (i *idler) Exit() {
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i.Tick()
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i.active.Add(-1)
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}
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func CreateIdler(timeout time.Duration) Idler {
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i := &idler{}
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i.c = make(chan struct{})
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i.Tick()
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go func() {
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for {
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if i.active.Load() != 0 {
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time.Sleep(timeout)
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} else {
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t := *i.lastTick.Load()
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now := time.Now()
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dur := t.Add(timeout).Sub(now)
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if dur == dur.Abs() {
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time.Sleep(dur)
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} else {
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break
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}
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}
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}
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close(i.c)
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}()
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return i
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}
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func (i *idler) Tick() {
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now := time.Now()
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i.lastTick.Store(&now)
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}
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func (i *idler) Wait() {
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<-i.c
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}
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func (i *idler) Chan() <-chan struct{} {
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return i.c
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}
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