47 lines
867 B
Go
47 lines
867 B
Go
package common
|
|
|
|
import (
|
|
"sync/atomic"
|
|
"time"
|
|
)
|
|
|
|
/*
|
|
Throttler sends a struct{}{} to .Ch "dur" after the last .Set().
|
|
It's good for ensuring that something happens last after a burst of events.
|
|
*/
|
|
type Throttler struct {
|
|
Ch chan struct{}
|
|
quit chan struct{}
|
|
dur time.Duration
|
|
timer *time.Timer
|
|
isSet uint32
|
|
}
|
|
|
|
func NewThrottler(dur time.Duration) *Throttler {
|
|
var ch = make(chan struct{})
|
|
var quit = make(chan struct{})
|
|
var t = &Throttler{Ch: ch, dur: dur, quit: quit}
|
|
t.timer = time.AfterFunc(dur, t.fireHandler)
|
|
t.timer.Stop()
|
|
return t
|
|
}
|
|
|
|
func (t *Throttler) fireHandler() {
|
|
select {
|
|
case t.Ch <- struct{}{}:
|
|
atomic.StoreUint32(&t.isSet, 0)
|
|
case <-t.quit:
|
|
}
|
|
}
|
|
|
|
func (t *Throttler) Set() {
|
|
if atomic.CompareAndSwapUint32(&t.isSet, 0, 1) {
|
|
t.timer.Reset(t.dur)
|
|
}
|
|
}
|
|
|
|
func (t *Throttler) Stop() bool {
|
|
close(t.quit)
|
|
return t.timer.Stop()
|
|
}
|