-
Notifications
You must be signed in to change notification settings - Fork 38.6k
/
system_namespaces_controller.go
104 lines (85 loc) · 2.97 KB
/
system_namespaces_controller.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
/*
Copyright 2023 The Kubernetes Authors.
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 systemnamespaces
import (
"context"
"fmt"
"time"
v1 "k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
utilruntime "k8s.io/apimachinery/pkg/util/runtime"
"k8s.io/apimachinery/pkg/util/wait"
coreinformers "k8s.io/client-go/informers/core/v1"
"k8s.io/client-go/kubernetes"
listers "k8s.io/client-go/listers/core/v1"
"k8s.io/client-go/tools/cache"
"k8s.io/klog/v2"
)
// Controller ensure system namespaces exist.
type Controller struct {
client kubernetes.Interface
namespaceLister listers.NamespaceLister
namespaceSynced cache.InformerSynced
systemNamespaces []string
interval time.Duration
}
// NewController creates a new Controller to ensure system namespaces exist.
func NewController(clientset kubernetes.Interface, namespaceInformer coreinformers.NamespaceInformer) *Controller {
systemNamespaces := []string{metav1.NamespaceSystem, metav1.NamespacePublic, v1.NamespaceNodeLease, metav1.NamespaceDefault}
interval := 1 * time.Minute
return &Controller{
client: clientset,
namespaceLister: namespaceInformer.Lister(),
namespaceSynced: namespaceInformer.Informer().HasSynced,
systemNamespaces: systemNamespaces,
interval: interval,
}
}
// Run starts one worker.
func (c *Controller) Run(stopCh <-chan struct{}) {
defer utilruntime.HandleCrash()
defer klog.Infof("Shutting down system namespaces controller")
klog.Infof("Starting system namespaces controller")
if !cache.WaitForCacheSync(stopCh, c.namespaceSynced) {
utilruntime.HandleError(fmt.Errorf("timed out waiting for caches to sync"))
return
}
go wait.Until(c.sync, c.interval, stopCh)
<-stopCh
}
func (c *Controller) sync() {
// Loop the system namespace list, and create them if they do not exist
for _, ns := range c.systemNamespaces {
if err := c.createNamespaceIfNeeded(ns); err != nil {
utilruntime.HandleError(fmt.Errorf("unable to create required kubernetes system Namespace %s: %v", ns, err))
}
}
}
func (c *Controller) createNamespaceIfNeeded(ns string) error {
if _, err := c.namespaceLister.Get(ns); err == nil {
// the namespace already exists
return nil
}
newNs := &v1.Namespace{
ObjectMeta: metav1.ObjectMeta{
Name: ns,
Namespace: "",
},
}
_, err := c.client.CoreV1().Namespaces().Create(context.TODO(), newNs, metav1.CreateOptions{})
if err != nil && errors.IsAlreadyExists(err) {
err = nil
}
return err
}