/
store.go
435 lines (365 loc) · 9.99 KB
/
store.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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
package store
import (
"bytes"
"encoding/json"
"errors"
"fmt"
"net"
"net/http"
"os"
"os/signal"
"path/filepath"
"syscall"
"time"
"github.com/golang/glog"
"github.com/hashicorp/raft"
"github.com/hashicorp/raft-boltdb"
"k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/fields"
clientset "k8s.io/client-go/kubernetes"
kcache "k8s.io/client-go/tools/cache"
"github.com/Colstuwjx/kstore/pkg/cache"
)
const (
// Resync period for the kube controller loop.
resyncPeriod = 5 * time.Second
timeout = 30 * time.Second
outOfDateTtl = 300 * time.Second
expireTtl = 60 * 24 * time.Hour
// raft configurations.
retainSnapshotCount = 2
raftTimeout = 10 * time.Second
leaderElectionTimeout = 30 * time.Second
ObjectTypePods = "pods"
)
type KStore struct {
// local cache
localCache *cache.LocalCache
kubeClient clientset.Interface
// stop chan with stop watching and graceful exit
stopChan chan struct{}
// Initial timeout for endpoints and services to be synced from APIServer
initialSyncTimeout time.Duration
// cached pods store
podsStore kcache.Store
// podsController invokes registered callbacks when pods change.
podsController kcache.Controller
// raft and consensus mechanism
RaftDir, RaftBind, JoinAddr string // TODO: ensure dir exists.
raft *raft.Raft
// http server configurations
HttpBind string
}
func (ks *KStore) setPodsStore() {
// Returns a cache.ListWatch that gets all changes to endpoints.
ks.podsStore, ks.podsController = kcache.NewInformer(
kcache.NewListWatchFromClient(
ks.kubeClient.Core().RESTClient(),
ObjectTypePods,
v1.NamespaceAll,
fields.Everything()),
&v1.Pod{},
resyncPeriod,
kcache.ResourceEventHandlerFuncs{
AddFunc: ks.addPodToCache,
UpdateFunc: ks.updatePodToCache,
DeleteFunc: ks.deletePodToCache,
},
)
}
func (ks *KStore) addPodToCache(obj interface{}) {
// if ks instance is not leader, skip write operation.
if ks.raft.State() != raft.Leader {
glog.V(5).Info("skipped `addPodToCache` due to I'm not leader")
return
}
addPod, ok := obj.(*v1.Pod)
if !ok {
glog.Error("received obj not pod type!")
return
}
c := &command{
Op: "add",
ObjectName: addPod.Name,
ObjectType: ObjectTypePods,
Old: nil,
New: addPod,
}
b, err := json.Marshal(c)
if err != nil {
glog.Errorf("marshal received addPod err: %s", err)
return
}
f := ks.raft.Apply(b, raftTimeout)
err = f.Error()
if err != nil {
glog.Errorf("apply raft log while adding pod err: %s", err)
return
}
}
func (ks *KStore) updatePodToCache(oldObj, newObj interface{}) {
// if ks instance is not leader, skip write operation.
if ks.raft.State() != raft.Leader {
glog.V(5).Info("skipped `updatePodToCache` due to I'm not leader")
return
}
oldPod, ok := oldObj.(*v1.Pod)
if !ok {
glog.Error("received old obj not pod type!")
return
}
newPod, ok := newObj.(*v1.Pod)
if !ok {
glog.Error("received new obj not pod type!")
return
}
c := &command{
Op: "update",
ObjectName: newPod.Name,
ObjectType: ObjectTypePods,
Old: oldPod,
New: newPod,
}
b, err := json.Marshal(c)
if err != nil {
glog.Errorf("marshal received updatePod err: %s", err)
return
}
f := ks.raft.Apply(b, raftTimeout)
err = f.Error()
if err != nil {
glog.Errorf("apply raft log while updating pod err: %s", err)
return
}
}
func (ks *KStore) deletePodToCache(delObj interface{}) {
// if ks instance is not leader, skip write operation.
// FIXME: we may lost the delete event, and resync can NOT help us
// as a solution, we need to check the POD update timestamp and mark deleted while it is not alive.
if ks.raft.State() != raft.Leader {
glog.V(5).Info("skipped `deletePodToCache` due to I'm not leader")
return
}
deletePod, ok := delObj.(*v1.Pod)
if !ok {
glog.Error("received delete obj not pod type!")
return
}
c := &command{
Op: "delete",
ObjectName: deletePod.Name,
ObjectType: ObjectTypePods,
Old: deletePod,
New: nil,
}
b, err := json.Marshal(c)
if err != nil {
glog.Errorf("marshal received deletePod err: %s", err)
return
}
f := ks.raft.Apply(b, raftTimeout)
err = f.Error()
if err != nil {
glog.Errorf("apply raft log while deleting pod err: %s", err)
return
}
}
func (ks *KStore) initRaft(enableSingleNode bool, localID string) error {
// Setup Raft configuration.
config := raft.DefaultConfig()
config.LocalID = raft.ServerID(localID)
// Setup Raft communication.
addr, err := net.ResolveTCPAddr("tcp", ks.RaftBind) // 内部选举通信端口
if err != nil {
return err
}
transport, err := raft.NewTCPTransport(ks.RaftBind, addr, 3, 10*time.Second, os.Stderr)
if err != nil {
return err
}
// Create the snapshot store. This allows the Raft to truncate the log.
snapshots, err := raft.NewFileSnapshotStore(ks.RaftDir, retainSnapshotCount, os.Stderr)
if err != nil {
return fmt.Errorf("file snapshot store: %s", err)
}
// Create the log store and stable store.
logStore, err := raftboltdb.NewBoltStore(filepath.Join(ks.RaftDir, "raft.db"))
if err != nil {
return fmt.Errorf("new bolt store: %s", err)
}
// Instantiate the Raft systems.
ra, err := raft.NewRaft(config, (*fsm)(ks), logStore, logStore, snapshots, transport)
if err != nil {
return fmt.Errorf("new raft: %s", err)
}
ks.raft = ra
if enableSingleNode {
configuration := raft.Configuration{
Servers: []raft.Server{
{
ID: config.LocalID,
Address: transport.LocalAddr(),
},
},
}
ra.BootstrapCluster(configuration)
}
return nil
}
func (ks *KStore) waitForResourceSyncedOrDie() {
// Wait for both controllers have completed an initial resource listing
timeout := time.After(ks.initialSyncTimeout)
ticker := time.NewTicker(500 * time.Millisecond)
defer ticker.Stop()
for {
select {
case <-timeout:
panic("Timeout waiting for initialization")
case <-ticker.C:
if ks.podsController.HasSynced() {
glog.Info("Initialized pods from apiserver...")
return
}
glog.Info("Waiting for pods to be initialized from apiserver...")
}
}
}
func (ks *KStore) Reset(data *map[string]*cache.ObjectDef) error {
return ks.localCache.Reset(data)
}
func (ks *KStore) watchLeaderElection(checkPeriod time.Duration, waitTimeout time.Duration) error {
// wait until leader elected.
t := time.NewTimer(checkPeriod)
timeout := time.After(waitTimeout)
for {
select {
case <-timeout:
return errors.New("election timeout")
case <-t.C:
t.Reset(checkPeriod)
ksLeader := ks.raft.Leader()
if ksLeader != "" {
glog.Infof("ks leader elected: %s", ksLeader)
return nil
}
}
}
}
func postJoinRequest(joinAddr, raftAddr, nodeID string) error {
b, err := json.Marshal(reqJoin{RemoteAddr: raftAddr, NodeId: nodeID})
if err != nil {
return err
}
resp, err := http.Post(fmt.Sprintf("http://%s/join", joinAddr), "application-type/json", bytes.NewReader(b))
if err != nil {
return err
}
defer resp.Body.Close()
return nil
}
func (ks *KStore) Start(enableSingleNode bool, localID string) {
glog.Info("kstore starting...")
// firstly, async run http server
// so we can call leader Join func and do join while initial raft peers.
go ks.ServeHttp()
glog.Info("initializing raft...")
if err := ks.initRaft(enableSingleNode, localID); err != nil {
panic(err)
}
if ks.JoinAddr != "" {
if err := postJoinRequest(ks.JoinAddr, ks.RaftBind, localID); err != nil {
glog.Fatalf("ks node %s join %s failed: %s", localID, ks.JoinAddr, err)
}
}
if err := ks.watchLeaderElection(time.Second*5, leaderElectionTimeout); err != nil {
panic(err)
}
glog.Info("Starting podsController...")
go ks.podsController.Run(ks.stopChan)
ks.waitForResourceSyncedOrDie()
glog.Info("kstore started!")
}
func (ks *KStore) WaitUtilStop() {
terminate := make(chan os.Signal, 1)
signal.Notify(terminate, syscall.SIGINT, syscall.SIGTERM)
<-terminate
if !ks.Stopped() {
// TODO: implement graceful shutdown cache and raft peer part.
// FIXME: need to fix gap period while I'm leader and stopped listwatch!
glog.V(0).Info("stopping listwatch and graceful shutdown.")
ks.Stop()
}
glog.V(0).Info("GoodBye!")
}
func (ks *KStore) ServeHttp() {
glog.Info("Starting http server...")
ks.setHttpHandlers()
glog.Fatal(http.ListenAndServe(ks.HttpBind, nil))
}
func (ks *KStore) Stop() {
close(ks.stopChan)
glog.Info("kstore listwatch stopped...")
}
func (ks *KStore) Stopped() bool {
if ks.stopChan != nil {
return false
} else {
return true
}
}
// Join do raft peer join(ONLY leader can do this)
func (ks *KStore) Join(nodeID, addr string) error {
glog.V(0).Infof("received join request for remote node %s at %s", nodeID, addr)
f := ks.raft.AddVoter(raft.ServerID(nodeID), raft.ServerAddress(addr), 0, 0)
if f.Error() != nil {
return f.Error()
}
glog.V(0).Infof("node %s at %s joined successfully", nodeID, addr)
return nil
}
func New(client clientset.Interface, httpBind, raftBind, raftDir, join string) *KStore {
ks := &KStore{
kubeClient: client,
initialSyncTimeout: timeout,
stopChan: make(chan struct{}),
RaftBind: raftBind,
RaftDir: raftDir,
HttpBind: httpBind,
JoinAddr: join,
}
indexers := cache.Indexers{}
indices := cache.Indices{}
ks.localCache = cache.NewLocalCache(indexers, indices, outOfDateTtl, expireTtl)
err := ks.localCache.Init()
if err != nil {
panic(err)
}
// initial indexers
newIndexers := make(map[string]cache.IndexFunc)
indexMethods := map[string][]string{
"deleted": []string{"delete", ""},
"podIP": []string{
"status.podIP", "",
},
"nodeName": []string{
"spec.nodeName", "",
},
"namespace": []string{
"metadata.namespace", "",
},
"env.appId": []string{
"spec.containers.env", "APP_ID",
},
}
// initial indexFunc via index func factory
for name, field := range indexMethods {
indexFunc := PodObjectIndexFuncFactory(field[0], field[1])
newIndexers[name] = indexFunc
}
err = ks.localCache.AddIndexers(newIndexers)
if err != nil {
panic(err)
}
ks.setPodsStore()
return ks
}