-
-
Notifications
You must be signed in to change notification settings - Fork 64
/
group.go
90 lines (74 loc) · 1.79 KB
/
group.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
90
package pond
import (
"context"
"sync"
)
// TaskGroup represents a group of related tasks
type TaskGroup struct {
pool *WorkerPool
waitGroup sync.WaitGroup
}
// Submit adds a task to this group and sends it to the worker pool to be executed
func (g *TaskGroup) Submit(task func()) {
g.waitGroup.Add(1)
g.pool.Submit(func() {
defer g.waitGroup.Done()
task()
})
}
// Wait waits until all the tasks in this group have completed
func (g *TaskGroup) Wait() {
// Wait for all tasks to complete
g.waitGroup.Wait()
}
// TaskGroupWithContext represents a group of related tasks associated to a context
type TaskGroupWithContext struct {
TaskGroup
ctx context.Context
cancel context.CancelFunc
errOnce sync.Once
err error
}
// Submit adds a task to this group and sends it to the worker pool to be executed
func (g *TaskGroupWithContext) Submit(task func() error) {
g.waitGroup.Add(1)
g.pool.Submit(func() {
defer g.waitGroup.Done()
// If context has already been cancelled, skip task execution
if g.ctx != nil {
select {
case <-g.ctx.Done():
return
default:
}
}
// don't actually ignore errors
err := task()
if err != nil {
g.errOnce.Do(func() {
g.err = err
if g.cancel != nil {
g.cancel()
}
})
}
})
}
// Wait blocks until either all the tasks submitted to this group have completed,
// one of them returned a non-nil error or the context associated to this group
// was canceled.
func (g *TaskGroupWithContext) Wait() error {
// Wait for all tasks to complete
tasksCompleted := make(chan struct{})
go func() {
g.waitGroup.Wait()
tasksCompleted <- struct{}{}
}()
select {
case <-tasksCompleted:
// If context was provided, cancel it to signal all running tasks to stop
g.cancel()
case <-g.ctx.Done():
}
return g.err
}