/
throttle_timer.go
89 lines (80 loc) · 2.01 KB
/
throttle_timer.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
// Copyright 2017 ZhongAn Information Technology Services Co.,Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package common
import (
"sync"
"time"
)
/*
ThrottleTimer fires an event at most "dur" after each .Set() call.
If a short burst of .Set() calls happens, ThrottleTimer fires once.
If a long continuous burst of .Set() calls happens, ThrottleTimer fires
at most once every "dur".
*/
type ThrottleTimer struct {
Name string
Ch chan struct{}
quit chan struct{}
dur time.Duration
mtx sync.Mutex
timer *time.Timer
isSet bool
}
func NewThrottleTimer(name string, dur time.Duration) *ThrottleTimer {
var ch = make(chan struct{})
var quit = make(chan struct{})
var t = &ThrottleTimer{Name: name, Ch: ch, dur: dur, quit: quit}
t.mtx.Lock()
t.timer = time.AfterFunc(dur, t.fireRoutine)
t.mtx.Unlock()
t.timer.Stop()
return t
}
func (t *ThrottleTimer) fireRoutine() {
t.mtx.Lock()
defer t.mtx.Unlock()
select {
case t.Ch <- struct{}{}:
t.isSet = false
case <-t.quit:
// do nothing
default:
t.timer.Reset(t.dur)
}
}
func (t *ThrottleTimer) Set() {
t.mtx.Lock()
defer t.mtx.Unlock()
if !t.isSet {
t.isSet = true
t.timer.Reset(t.dur)
}
}
func (t *ThrottleTimer) Unset() {
t.mtx.Lock()
defer t.mtx.Unlock()
t.isSet = false
t.timer.Stop()
}
// For ease of .Stop()'ing services before .Start()'ing them,
// we ignore .Stop()'s on nil ThrottleTimers
func (t *ThrottleTimer) Stop() bool {
if t == nil {
return false
}
close(t.quit)
t.mtx.Lock()
defer t.mtx.Unlock()
return t.timer.Stop()
}