-
Notifications
You must be signed in to change notification settings - Fork 3
/
eventsource.go
67 lines (53 loc) · 1007 Bytes
/
eventsource.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
package eventhub
import "sync"
type Source interface {
Next() (Event, error)
Close() error
send(Event) error
}
type source struct {
events chan Event
closed bool
lock sync.Mutex
}
func newSource(maxPendingEvents int) Source {
return &source{
events: make(chan Event, maxPendingEvents),
}
}
func (source *source) Next() (Event, error) {
event, ok := <-source.events
if !ok {
return nil, ErrReadFromClosedSource
}
return event, nil
}
func (source *source) Close() error {
source.lock.Lock()
defer source.lock.Unlock()
if source.closed {
return ErrSourceAlreadyClosed
}
close(source.events)
source.closed = true
return nil
}
func (source *source) send(event Event) error {
source.lock.Lock()
if source.closed {
source.lock.Unlock()
return ErrSendToClosedSource
}
select {
case source.events <- event:
source.lock.Unlock()
return nil
default:
source.lock.Unlock()
err := source.Close()
if err != nil {
return err
}
return ErrSlowConsumer
}
}