1/*
2Copyright 2018 The Kubernetes Authors.
3
4Licensed under the Apache License, Version 2.0 (the "License");
5you may not use this file except in compliance with the License.
6You may obtain a copy of the License at
7
8    http://www.apache.org/licenses/LICENSE-2.0
9
10Unless required by applicable law or agreed to in writing, software
11distributed under the License is distributed on an "AS IS" BASIS,
12WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13See the License for the specific language governing permissions and
14limitations under the License.
15*/
16
17package metadatainformer
18
19import (
20	"context"
21	"sync"
22	"time"
23
24	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
25	"k8s.io/apimachinery/pkg/runtime"
26	"k8s.io/apimachinery/pkg/runtime/schema"
27	"k8s.io/apimachinery/pkg/watch"
28	"k8s.io/client-go/informers"
29	"k8s.io/client-go/metadata"
30	"k8s.io/client-go/metadata/metadatalister"
31	"k8s.io/client-go/tools/cache"
32)
33
34// NewSharedInformerFactory constructs a new instance of metadataSharedInformerFactory for all namespaces.
35func NewSharedInformerFactory(client metadata.Interface, defaultResync time.Duration) SharedInformerFactory {
36	return NewFilteredSharedInformerFactory(client, defaultResync, metav1.NamespaceAll, nil)
37}
38
39// NewFilteredSharedInformerFactory constructs a new instance of metadataSharedInformerFactory.
40// Listers obtained via this factory will be subject to the same filters as specified here.
41func NewFilteredSharedInformerFactory(client metadata.Interface, defaultResync time.Duration, namespace string, tweakListOptions TweakListOptionsFunc) SharedInformerFactory {
42	return &metadataSharedInformerFactory{
43		client:           client,
44		defaultResync:    defaultResync,
45		namespace:        namespace,
46		informers:        map[schema.GroupVersionResource]informers.GenericInformer{},
47		startedInformers: make(map[schema.GroupVersionResource]bool),
48		tweakListOptions: tweakListOptions,
49	}
50}
51
52type metadataSharedInformerFactory struct {
53	client        metadata.Interface
54	defaultResync time.Duration
55	namespace     string
56
57	lock      sync.Mutex
58	informers map[schema.GroupVersionResource]informers.GenericInformer
59	// startedInformers is used for tracking which informers have been started.
60	// This allows Start() to be called multiple times safely.
61	startedInformers map[schema.GroupVersionResource]bool
62	tweakListOptions TweakListOptionsFunc
63}
64
65var _ SharedInformerFactory = &metadataSharedInformerFactory{}
66
67func (f *metadataSharedInformerFactory) ForResource(gvr schema.GroupVersionResource) informers.GenericInformer {
68	f.lock.Lock()
69	defer f.lock.Unlock()
70
71	key := gvr
72	informer, exists := f.informers[key]
73	if exists {
74		return informer
75	}
76
77	informer = NewFilteredMetadataInformer(f.client, gvr, f.namespace, f.defaultResync, cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc}, f.tweakListOptions)
78	f.informers[key] = informer
79
80	return informer
81}
82
83// Start initializes all requested informers.
84func (f *metadataSharedInformerFactory) Start(stopCh <-chan struct{}) {
85	f.lock.Lock()
86	defer f.lock.Unlock()
87
88	for informerType, informer := range f.informers {
89		if !f.startedInformers[informerType] {
90			go informer.Informer().Run(stopCh)
91			f.startedInformers[informerType] = true
92		}
93	}
94}
95
96// WaitForCacheSync waits for all started informers' cache were synced.
97func (f *metadataSharedInformerFactory) WaitForCacheSync(stopCh <-chan struct{}) map[schema.GroupVersionResource]bool {
98	informers := func() map[schema.GroupVersionResource]cache.SharedIndexInformer {
99		f.lock.Lock()
100		defer f.lock.Unlock()
101
102		informers := map[schema.GroupVersionResource]cache.SharedIndexInformer{}
103		for informerType, informer := range f.informers {
104			if f.startedInformers[informerType] {
105				informers[informerType] = informer.Informer()
106			}
107		}
108		return informers
109	}()
110
111	res := map[schema.GroupVersionResource]bool{}
112	for informType, informer := range informers {
113		res[informType] = cache.WaitForCacheSync(stopCh, informer.HasSynced)
114	}
115	return res
116}
117
118// NewFilteredMetadataInformer constructs a new informer for a metadata type.
119func NewFilteredMetadataInformer(client metadata.Interface, gvr schema.GroupVersionResource, namespace string, resyncPeriod time.Duration, indexers cache.Indexers, tweakListOptions TweakListOptionsFunc) informers.GenericInformer {
120	return &metadataInformer{
121		gvr: gvr,
122		informer: cache.NewSharedIndexInformer(
123			&cache.ListWatch{
124				ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
125					if tweakListOptions != nil {
126						tweakListOptions(&options)
127					}
128					return client.Resource(gvr).Namespace(namespace).List(context.TODO(), options)
129				},
130				WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
131					if tweakListOptions != nil {
132						tweakListOptions(&options)
133					}
134					return client.Resource(gvr).Namespace(namespace).Watch(context.TODO(), options)
135				},
136			},
137			&metav1.PartialObjectMetadata{},
138			resyncPeriod,
139			indexers,
140		),
141	}
142}
143
144type metadataInformer struct {
145	informer cache.SharedIndexInformer
146	gvr      schema.GroupVersionResource
147}
148
149var _ informers.GenericInformer = &metadataInformer{}
150
151func (d *metadataInformer) Informer() cache.SharedIndexInformer {
152	return d.informer
153}
154
155func (d *metadataInformer) Lister() cache.GenericLister {
156	return metadatalister.NewRuntimeObjectShim(metadatalister.New(d.informer.GetIndexer(), d.gvr))
157}
158