/
resources.go
130 lines (121 loc) · 3.82 KB
/
resources.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
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
// Copyright 2016-2020 Authors of Cilium
//
// 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 synced
import (
"time"
"github.com/cilium/cilium/pkg/lock"
"k8s.io/client-go/tools/cache"
)
// Resources maps resource names to channels that are closed upon initial
// sync with k8s.
type Resources struct {
lock.RWMutex
// resourceChannels maps a resource name to a channel. Once the given
// resource name is synchronized with k8s, the channel for which that
// resource name maps to is closed.
resources map[string]<-chan struct{}
// stopWait contains the result of cache.WaitForCacheSync
stopWait map[string]bool
}
func (r *Resources) CancelWaitGroupToSyncResources(resourceName string) {
r.Lock()
delete(r.resources, resourceName)
r.Unlock()
}
// BlockWaitGroupToSyncResources ensures that anything which waits on waitGroup
// waits until all objects of the specified resource stored in Kubernetes are
// received by the informer and processed by controller.
// Fatally exits if syncing these initial objects fails.
// If the given stop channel is closed, it does not fatal.
// Once the k8s caches are synced against k8s, k8sCacheSynced is also closed.
func (r *Resources) BlockWaitGroupToSyncResources(
stop <-chan struct{},
swg *lock.StoppableWaitGroup,
hasSyncedFunc cache.InformerSynced,
resourceName string,
) {
ch := make(chan struct{})
r.Lock()
if r.resources == nil {
r.resources = make(map[string]<-chan struct{})
r.stopWait = make(map[string]bool)
}
r.resources[resourceName] = ch
r.Unlock()
go func() {
scopedLog := log.WithField("kubernetesResource", resourceName)
scopedLog.Debug("waiting for cache to synchronize")
if ok := cache.WaitForCacheSync(stop, hasSyncedFunc); !ok {
select {
case <-stop:
// do not fatal if the channel was stopped
scopedLog.Debug("canceled cache synchronization")
r.Lock()
// Since the wait for cache sync was canceled we
// need to mark that stopWait was canceled and it
// should not stop waiting for this resource to be
// synchronized.
r.stopWait[resourceName] = false
r.Unlock()
default:
// Fatally exit it resource fails to sync
scopedLog.Fatalf("failed to wait for cache to sync")
}
} else {
scopedLog.Debug("cache synced")
r.Lock()
// Since the wait for cache sync was not canceled we need to
// mark that stopWait not canceled and it should stop
// waiting for this resource to be synchronized.
r.stopWait[resourceName] = true
r.Unlock()
}
if swg != nil {
swg.Stop()
swg.Wait()
}
close(ch)
}()
}
// WaitForCacheSync waits for all K8s resources represented by
// resourceNames to have their K8s caches synchronized.
func (r *Resources) WaitForCacheSync(resourceNames ...string) {
for _, resourceName := range resourceNames {
r.RLock()
c, ok := r.resources[resourceName]
r.RUnlock()
if !ok {
continue
}
for {
scopedLog := log.WithField("kubernetesResource", resourceName)
<-c
r.RLock()
stopWait := r.stopWait[resourceName]
r.RUnlock()
if stopWait {
scopedLog.Debug("stopped waiting for caches to be synced")
break
}
scopedLog.Debug("original cache sync operation was aborted, waiting for caches to be synced with a new channel...")
time.Sleep(100 * time.Millisecond)
r.RLock()
c, ok = r.resources[resourceName]
r.RUnlock()
if !ok {
break
}
}
}
}