forked from openshift/origin
-
Notifications
You must be signed in to change notification settings - Fork 1
/
rolling_updater.go
640 lines (596 loc) · 26.1 KB
/
rolling_updater.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
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
/*
Copyright 2014 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 rolling
// This file is a copy of k8s.io/kubernetes/pkg/kubectl/cmd/rollingupdate.go.
// It has been inlined as that location is effectively unmaintained and this
// package must maintain backwards compatibility with older openshift versions.
import (
"fmt"
"io"
"strconv"
"time"
api "k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/apimachinery/pkg/util/intstr"
"k8s.io/apimachinery/pkg/util/wait"
coreclient "k8s.io/client-go/kubernetes/typed/core/v1"
scaleclient "k8s.io/client-go/scale"
"k8s.io/client-go/util/integer"
"k8s.io/client-go/util/retry"
podutil "k8s.io/kubernetes/pkg/api/v1/pod"
deploymentutil "k8s.io/kubernetes/pkg/controller/deployment/util"
"k8s.io/kubernetes/pkg/kubectl"
)
// ControllerHasDesiredReplicas returns a condition that will be true if and only if
// the desired replica count for a controller's ReplicaSelector equals the Replicas count.
func ControllerHasDesiredReplicas(rcClient coreclient.ReplicationControllersGetter, controller *api.ReplicationController) wait.ConditionFunc {
// If we're given a controller where the status lags the spec, it either means that the controller is stale,
// or that the rc manager hasn't noticed the update yet. Polling status.Replicas is not safe in the latter case.
desiredGeneration := controller.Generation
return func() (bool, error) {
ctrl, err := rcClient.ReplicationControllers(controller.Namespace).Get(controller.Name, metav1.GetOptions{})
if err != nil {
return false, err
}
// There's a chance a concurrent update modifies the Spec.Replicas causing this check to pass,
// or, after this check has passed, a modification causes the rc manager to create more pods.
// This will not be an issue once we've implemented graceful delete for rcs, but till then
// concurrent stop operations on the same rc might have unintended side effects.
return ctrl.Status.ObservedGeneration >= desiredGeneration && ctrl.Status.Replicas == *ctrl.Spec.Replicas, nil
}
}
const (
kubectlAnnotationPrefix = "kubectl.kubernetes.io/"
sourceIdAnnotation = kubectlAnnotationPrefix + "update-source-id"
desiredReplicasAnnotation = kubectlAnnotationPrefix + "desired-replicas"
originalReplicasAnnotation = kubectlAnnotationPrefix + "original-replicas"
)
// RollingUpdaterConfig is the configuration for a rolling deployment process.
type RollingUpdaterConfig struct {
// Out is a writer for progress output.
Out io.Writer
// OldRC is an existing controller to be replaced.
OldRc *api.ReplicationController
// NewRc is a controller that will take ownership of updated pods (will be
// created if needed).
NewRc *api.ReplicationController
// UpdatePeriod is the time to wait between individual pod updates.
UpdatePeriod time.Duration
// Interval is the time to wait between polling controller status after
// update.
Interval time.Duration
// Timeout is the time to wait for controller updates before giving up.
Timeout time.Duration
// MinReadySeconds is the number of seconds to wait after the pods are ready
MinReadySeconds int32
// CleanupPolicy defines the cleanup action to take after the deployment is
// complete.
CleanupPolicy RollingUpdaterCleanupPolicy
// MaxUnavailable is the maximum number of pods that can be unavailable during the update.
// Value can be an absolute number (ex: 5) or a percentage of desired pods (ex: 10%).
// Absolute number is calculated from percentage by rounding up.
// This can not be 0 if MaxSurge is 0.
// By default, a fixed value of 1 is used.
// Example: when this is set to 30%, the old RC can be scaled down to 70% of desired pods
// immediately when the rolling update starts. Once new pods are ready, old RC
// can be scaled down further, followed by scaling up the new RC, ensuring
// that the total number of pods available at all times during the update is at
// least 70% of desired pods.
MaxUnavailable intstr.IntOrString
// MaxSurge is the maximum number of pods that can be scheduled above the desired number of pods.
// Value can be an absolute number (ex: 5) or a percentage of desired pods (ex: 10%).
// This can not be 0 if MaxUnavailable is 0.
// Absolute number is calculated from percentage by rounding up.
// By default, a value of 1 is used.
// Example: when this is set to 30%, the new RC can be scaled up immediately
// when the rolling update starts, such that the total number of old and new pods do not exceed
// 130% of desired pods. Once old pods have been killed, new RC can be scaled up
// further, ensuring that total number of pods running at any time during
// the update is atmost 130% of desired pods.
MaxSurge intstr.IntOrString
// OnProgress is invoked if set during each scale cycle, to allow the caller to perform additional logic or
// abort the scale. If an error is returned the cleanup method will not be invoked. The percentage value
// is a synthetic "progress" calculation that represents the approximate percentage completion.
OnProgress func(oldRc, newRc *api.ReplicationController, percentage int) error
}
// RollingUpdaterCleanupPolicy is a cleanup action to take after the
// deployment is complete.
type RollingUpdaterCleanupPolicy string
const (
// DeleteRollingUpdateCleanupPolicy means delete the old controller.
DeleteRollingUpdateCleanupPolicy RollingUpdaterCleanupPolicy = "Delete"
// PreserveRollingUpdateCleanupPolicy means keep the old controller.
PreserveRollingUpdateCleanupPolicy RollingUpdaterCleanupPolicy = "Preserve"
// RenameRollingUpdateCleanupPolicy means delete the old controller, and rename
// the new controller to the name of the old controller.
RenameRollingUpdateCleanupPolicy RollingUpdaterCleanupPolicy = "Rename"
)
// RollingUpdater provides methods for updating replicated pods in a predictable,
// fault-tolerant way.
type RollingUpdater struct {
rcClient coreclient.ReplicationControllersGetter
podClient coreclient.PodsGetter
scaleClient scaleclient.ScalesGetter
// Namespace for resources
ns string
// scaleAndWait scales a controller and returns its updated state.
scaleAndWait func(rc *api.ReplicationController, retry *kubectl.RetryParams, wait *kubectl.RetryParams) (*api.ReplicationController, error)
// getOrCreateTargetController gets and validates an existing controller or
// makes a new one.
getOrCreateTargetController func(controller *api.ReplicationController, sourceId string) (*api.ReplicationController, bool, error)
// cleanup performs post deployment cleanup tasks for newRc and oldRc.
cleanup func(oldRc, newRc *api.ReplicationController, config *RollingUpdaterConfig) error
// getReadyPods returns the amount of old and new ready pods.
getReadyPods func(oldRc, newRc *api.ReplicationController, minReadySeconds int32) (int32, int32, error)
// nowFn returns the current time used to calculate the minReadySeconds
nowFn func() metav1.Time
}
// NewRollingUpdater creates a RollingUpdater from a client.
func NewRollingUpdater(namespace string, rcClient coreclient.ReplicationControllersGetter, podClient coreclient.PodsGetter, sc scaleclient.ScalesGetter) *RollingUpdater {
updater := &RollingUpdater{
rcClient: rcClient,
podClient: podClient,
scaleClient: sc,
ns: namespace,
}
// Inject real implementations.
updater.scaleAndWait = updater.scaleAndWaitWithScaler
updater.getOrCreateTargetController = updater.getOrCreateTargetControllerWithClient
updater.getReadyPods = updater.readyPods
updater.cleanup = updater.cleanupWithClients
updater.nowFn = metav1.Now
return updater
}
// Update all pods for a ReplicationController (oldRc) by creating a new
// controller (newRc) with 0 replicas, and synchronously scaling oldRc and
// newRc until oldRc has 0 replicas and newRc has the original # of desired
// replicas. Cleanup occurs based on a RollingUpdaterCleanupPolicy.
//
// Each interval, the updater will attempt to make progress however it can
// without violating any availability constraints defined by the config. This
// means the amount scaled up or down each interval will vary based on the
// timeliness of readiness and the updater will always try to make progress,
// even slowly.
//
// If an update from newRc to oldRc is already in progress, we attempt to
// drive it to completion. If an error occurs at any step of the update, the
// error will be returned.
//
// A scaling event (either up or down) is considered progress; if no progress
// is made within the config.Timeout, an error is returned.
//
// TODO: make this handle performing a rollback of a partially completed
// rollout.
func (r *RollingUpdater) Update(config *RollingUpdaterConfig) error {
out := config.Out
oldRc := config.OldRc
if oldRc.Spec.Replicas == nil {
one := int32(1)
oldRc.Spec.Replicas = &one
}
scaleRetryParams := kubectl.NewRetryParams(config.Interval, config.Timeout)
// Find an existing controller (for continuing an interrupted update) or
// create a new one if necessary.
sourceId := fmt.Sprintf("%s:%s", oldRc.Name, oldRc.UID)
newRc, existed, err := r.getOrCreateTargetController(config.NewRc, sourceId)
if err != nil {
return err
}
if newRc.Spec.Replicas == nil {
one := int32(1)
newRc.Spec.Replicas = &one
}
if existed {
fmt.Fprintf(out, "Continuing update with existing controller %s.\n", newRc.Name)
} else {
fmt.Fprintf(out, "Created %s\n", newRc.Name)
}
// Extract the desired replica count from the controller.
desiredAnnotation, err := strconv.Atoi(newRc.Annotations[desiredReplicasAnnotation])
if err != nil {
return fmt.Errorf("unable to parse annotation for %s: %s=%s",
newRc.Name, desiredReplicasAnnotation, newRc.Annotations[desiredReplicasAnnotation])
}
desired := int32(desiredAnnotation)
// Extract the original replica count from the old controller, adding the
// annotation if it doesn't yet exist.
_, hasOriginalAnnotation := oldRc.Annotations[originalReplicasAnnotation]
if !hasOriginalAnnotation {
existing, err := r.rcClient.ReplicationControllers(oldRc.Namespace).Get(oldRc.Name, metav1.GetOptions{})
if err != nil {
return err
}
if existing.Spec.Replicas != nil {
originReplicas := strconv.Itoa(int(*existing.Spec.Replicas))
applyUpdate := func(rc *api.ReplicationController) {
if rc.Annotations == nil {
rc.Annotations = map[string]string{}
}
rc.Annotations[originalReplicasAnnotation] = originReplicas
}
if oldRc, err = updateRcWithRetries(r.rcClient, existing.Namespace, existing, applyUpdate); err != nil {
return err
}
}
}
// maxSurge is the maximum scaling increment and maxUnavailable are the maximum pods
// that can be unavailable during a rollout.
maxSurge, maxUnavailable, err := deploymentutil.ResolveFenceposts(&config.MaxSurge, &config.MaxUnavailable, desired)
if err != nil {
return err
}
// Validate maximums.
if desired > 0 && maxUnavailable == 0 && maxSurge == 0 {
return fmt.Errorf("one of maxSurge or maxUnavailable must be specified")
}
// The minimum pods which must remain available throughout the update
// calculated for internal convenience.
minAvailable := int32(integer.IntMax(0, int(desired-maxUnavailable)))
// If the desired new scale is 0, then the max unavailable is necessarily
// the effective scale of the old RC regardless of the configuration
// (equivalent to 100% maxUnavailable).
if desired == 0 {
maxUnavailable = *oldRc.Spec.Replicas
minAvailable = 0
}
fmt.Fprintf(out, "Scaling up %s from %d to %d, scaling down %s from %d to 0 (keep %d pods available, don't exceed %d pods)\n",
newRc.Name, *newRc.Spec.Replicas, desired, oldRc.Name, *oldRc.Spec.Replicas, minAvailable, desired+maxSurge)
// give a caller incremental notification and allow them to exit early
goal := desired - *newRc.Spec.Replicas
if goal < 0 {
goal = -goal
}
progress := func(complete bool) error {
if config.OnProgress == nil {
return nil
}
progress := desired - *newRc.Spec.Replicas
if progress < 0 {
progress = -progress
}
percentage := 100
if !complete && goal > 0 {
percentage = int((goal - progress) * 100 / goal)
}
return config.OnProgress(oldRc, newRc, percentage)
}
// Scale newRc and oldRc until newRc has the desired number of replicas and
// oldRc has 0 replicas.
progressDeadline := time.Now().UnixNano() + config.Timeout.Nanoseconds()
for *newRc.Spec.Replicas != desired || *oldRc.Spec.Replicas != 0 {
// Store the existing replica counts for progress timeout tracking.
newReplicas := *newRc.Spec.Replicas
oldReplicas := *oldRc.Spec.Replicas
// Scale up as much as possible.
scaledRc, err := r.scaleUp(newRc, oldRc, desired, maxSurge, maxUnavailable, scaleRetryParams, config)
if err != nil {
return err
}
newRc = scaledRc
// notify the caller if necessary
if err := progress(false); err != nil {
return err
}
// Wait between scaling operations for things to settle.
time.Sleep(config.UpdatePeriod)
// Scale down as much as possible.
scaledRc, err = r.scaleDown(newRc, oldRc, desired, minAvailable, maxUnavailable, maxSurge, config)
if err != nil {
return err
}
oldRc = scaledRc
// notify the caller if necessary
if err := progress(false); err != nil {
return err
}
// If we are making progress, continue to advance the progress deadline.
// Otherwise, time out with an error.
progressMade := (*newRc.Spec.Replicas != newReplicas) || (*oldRc.Spec.Replicas != oldReplicas)
if progressMade {
progressDeadline = time.Now().UnixNano() + config.Timeout.Nanoseconds()
} else if time.Now().UnixNano() > progressDeadline {
return fmt.Errorf("timed out waiting for any update progress to be made")
}
}
// notify the caller if necessary
if err := progress(true); err != nil {
return err
}
// Housekeeping and cleanup policy execution.
return r.cleanup(oldRc, newRc, config)
}
// scaleUp scales up newRc to desired by whatever increment is possible given
// the configured surge threshold. scaleUp will safely no-op as necessary when
// it detects redundancy or other relevant conditions.
func (r *RollingUpdater) scaleUp(newRc, oldRc *api.ReplicationController, desired, maxSurge, maxUnavailable int32, scaleRetryParams *kubectl.RetryParams, config *RollingUpdaterConfig) (*api.ReplicationController, error) {
// If we're already at the desired, do nothing.
if *newRc.Spec.Replicas == desired {
return newRc, nil
}
// Scale up as far as we can based on the surge limit.
increment := (desired + maxSurge) - (*oldRc.Spec.Replicas + *newRc.Spec.Replicas)
// If the old is already scaled down, go ahead and scale all the way up.
if *oldRc.Spec.Replicas == 0 {
increment = desired - *newRc.Spec.Replicas
}
// We can't scale up without violating the surge limit, so do nothing.
if increment <= 0 {
return newRc, nil
}
// Increase the replica count, and deal with fenceposts.
*newRc.Spec.Replicas += increment
if *newRc.Spec.Replicas > desired {
*newRc.Spec.Replicas = desired
}
// Perform the scale-up.
fmt.Fprintf(config.Out, "Scaling %s up to %d\n", newRc.Name, *newRc.Spec.Replicas)
scaledRc, err := r.scaleAndWait(newRc, scaleRetryParams, scaleRetryParams)
if err != nil {
return nil, err
}
return scaledRc, nil
}
// scaleDown scales down oldRc to 0 at whatever decrement possible given the
// thresholds defined on the config. scaleDown will safely no-op as necessary
// when it detects redundancy or other relevant conditions.
func (r *RollingUpdater) scaleDown(newRc, oldRc *api.ReplicationController, desired, minAvailable, maxUnavailable, maxSurge int32, config *RollingUpdaterConfig) (*api.ReplicationController, error) {
// Already scaled down; do nothing.
if *oldRc.Spec.Replicas == 0 {
return oldRc, nil
}
// Get ready pods. We shouldn't block, otherwise in case both old and new
// pods are unavailable then the rolling update process blocks.
// Timeout-wise we are already covered by the progress check.
_, newAvailable, err := r.getReadyPods(oldRc, newRc, config.MinReadySeconds)
if err != nil {
return nil, err
}
// The old controller is considered as part of the total because we want to
// maintain minimum availability even with a volatile old controller.
// Scale down as much as possible while maintaining minimum availability
allPods := *oldRc.Spec.Replicas + *newRc.Spec.Replicas
newUnavailable := *newRc.Spec.Replicas - newAvailable
decrement := allPods - minAvailable - newUnavailable
// The decrement normally shouldn't drop below 0 because the available count
// always starts below the old replica count, but the old replica count can
// decrement due to externalities like pods death in the replica set. This
// will be considered a transient condition; do nothing and try again later
// with new readiness values.
//
// If the most we can scale is 0, it means we can't scale down without
// violating the minimum. Do nothing and try again later when conditions may
// have changed.
if decrement <= 0 {
return oldRc, nil
}
// Reduce the replica count, and deal with fenceposts.
*oldRc.Spec.Replicas -= decrement
if *oldRc.Spec.Replicas < 0 {
*oldRc.Spec.Replicas = 0
}
// If the new is already fully scaled and available up to the desired size, go
// ahead and scale old all the way down.
if *newRc.Spec.Replicas == desired && newAvailable == desired {
*oldRc.Spec.Replicas = 0
}
// Perform the scale-down.
fmt.Fprintf(config.Out, "Scaling %s down to %d\n", oldRc.Name, *oldRc.Spec.Replicas)
retryWait := &kubectl.RetryParams{Interval: config.Interval, Timeout: config.Timeout}
scaledRc, err := r.scaleAndWait(oldRc, retryWait, retryWait)
if err != nil {
return nil, err
}
return scaledRc, nil
}
// scalerScaleAndWait scales a controller using a Scaler and a real client.
func (r *RollingUpdater) scaleAndWaitWithScaler(rc *api.ReplicationController, retry, wait *kubectl.RetryParams) (*api.ReplicationController, error) {
scaler := kubectl.NewScaler(r.scaleClient)
if err := scaler.Scale(rc.Namespace, rc.Name, uint(*rc.Spec.Replicas), &kubectl.ScalePrecondition{Size: -1}, retry, wait, schema.GroupResource{Resource: "replicationcontrollers"}); err != nil {
return nil, err
}
return r.rcClient.ReplicationControllers(rc.Namespace).Get(rc.Name, metav1.GetOptions{})
}
// readyPods returns the old and new ready counts for their pods.
// If a pod is observed as being ready, it's considered ready even
// if it later becomes notReady.
func (r *RollingUpdater) readyPods(oldRc, newRc *api.ReplicationController, minReadySeconds int32) (int32, int32, error) {
controllers := []*api.ReplicationController{oldRc, newRc}
oldReady := int32(0)
newReady := int32(0)
if r.nowFn == nil {
r.nowFn = metav1.Now
}
for i := range controllers {
controller := controllers[i]
selector := labels.Set(controller.Spec.Selector).AsSelector()
options := metav1.ListOptions{LabelSelector: selector.String()}
pods, err := r.podClient.Pods(controller.Namespace).List(options)
if err != nil {
return 0, 0, err
}
for _, pod := range pods.Items {
// Do not count deleted pods as ready
if pod.DeletionTimestamp != nil {
continue
}
if !podutil.IsPodAvailable(&pod, minReadySeconds, r.nowFn()) {
continue
}
switch controller.Name {
case oldRc.Name:
oldReady++
case newRc.Name:
newReady++
}
}
}
return oldReady, newReady, nil
}
// getOrCreateTargetControllerWithClient looks for an existing controller with
// sourceId. If found, the existing controller is returned with true
// indicating that the controller already exists. If the controller isn't
// found, a new one is created and returned along with false indicating the
// controller was created.
//
// Existing controllers are validated to ensure their sourceIdAnnotation
// matches sourceId; if there's a mismatch, an error is returned.
func (r *RollingUpdater) getOrCreateTargetControllerWithClient(controller *api.ReplicationController, sourceId string) (*api.ReplicationController, bool, error) {
existingRc, err := r.existingController(controller)
if err != nil {
if !errors.IsNotFound(err) {
// There was an error trying to find the controller; don't assume we
// should create it.
return nil, false, err
}
if controller.Spec.Replicas == nil || *controller.Spec.Replicas <= 0 {
return nil, false, fmt.Errorf("Invalid controller spec for %s; required: > 0 replicas, actual: %d\n", controller.Name, controller.Spec.Replicas)
}
// The controller wasn't found, so create it.
if controller.Annotations == nil {
controller.Annotations = map[string]string{}
}
controller.Annotations[desiredReplicasAnnotation] = fmt.Sprintf("%d", controller.Spec.Replicas)
controller.Annotations[sourceIdAnnotation] = sourceId
zero := int32(0)
controller.Spec.Replicas = &zero
newRc, err := r.rcClient.ReplicationControllers(r.ns).Create(controller)
return newRc, false, err
}
// Validate and use the existing controller.
annotations := existingRc.Annotations
source := annotations[sourceIdAnnotation]
_, ok := annotations[desiredReplicasAnnotation]
if source != sourceId || !ok {
return nil, false, fmt.Errorf("missing/unexpected annotations for controller %s, expected %s : %s", controller.Name, sourceId, annotations)
}
return existingRc, true, nil
}
// existingController verifies if the controller already exists
func (r *RollingUpdater) existingController(controller *api.ReplicationController) (*api.ReplicationController, error) {
// without rc name but generate name, there's no existing rc
if len(controller.Name) == 0 && len(controller.GenerateName) > 0 {
return nil, errors.NewNotFound(api.Resource("replicationcontrollers"), controller.Name)
}
// controller name is required to get rc back
return r.rcClient.ReplicationControllers(controller.Namespace).Get(controller.Name, metav1.GetOptions{})
}
// cleanupWithClients performs cleanup tasks after the rolling update. Update
// process related annotations are removed from oldRc and newRc. The
// CleanupPolicy on config is executed.
func (r *RollingUpdater) cleanupWithClients(oldRc, newRc *api.ReplicationController, config *RollingUpdaterConfig) error {
// Clean up annotations
var err error
newRc, err = r.rcClient.ReplicationControllers(r.ns).Get(newRc.Name, metav1.GetOptions{})
if err != nil {
return err
}
applyUpdate := func(rc *api.ReplicationController) {
delete(rc.Annotations, sourceIdAnnotation)
delete(rc.Annotations, desiredReplicasAnnotation)
}
if newRc, err = updateRcWithRetries(r.rcClient, r.ns, newRc, applyUpdate); err != nil {
return err
}
if err = wait.Poll(config.Interval, config.Timeout, ControllerHasDesiredReplicas(r.rcClient, newRc)); err != nil {
return err
}
newRc, err = r.rcClient.ReplicationControllers(r.ns).Get(newRc.Name, metav1.GetOptions{})
if err != nil {
return err
}
switch config.CleanupPolicy {
case DeleteRollingUpdateCleanupPolicy:
// delete old rc
fmt.Fprintf(config.Out, "Update succeeded. Deleting %s\n", oldRc.Name)
return r.rcClient.ReplicationControllers(r.ns).Delete(oldRc.Name, nil)
case RenameRollingUpdateCleanupPolicy:
// delete old rc
fmt.Fprintf(config.Out, "Update succeeded. Deleting old controller: %s\n", oldRc.Name)
if err := r.rcClient.ReplicationControllers(r.ns).Delete(oldRc.Name, nil); err != nil {
return err
}
fmt.Fprintf(config.Out, "Renaming %s to %s\n", newRc.Name, oldRc.Name)
return Rename(r.rcClient, newRc, oldRc.Name)
case PreserveRollingUpdateCleanupPolicy:
return nil
default:
return nil
}
}
func Rename(c coreclient.ReplicationControllersGetter, rc *api.ReplicationController, newName string) error {
oldName := rc.Name
rc.Name = newName
rc.ResourceVersion = ""
// First delete the oldName RC and orphan its pods.
propagation := metav1.DeletePropagationOrphan
err := c.ReplicationControllers(rc.Namespace).Delete(oldName, &metav1.DeleteOptions{PropagationPolicy: &propagation})
if err != nil && !errors.IsNotFound(err) {
return err
}
err = wait.Poll(5*time.Second, 60*time.Second, func() (bool, error) {
_, err := c.ReplicationControllers(rc.Namespace).Get(oldName, metav1.GetOptions{})
if err == nil {
return false, nil
} else if errors.IsNotFound(err) {
return true, nil
} else {
return false, err
}
})
if err != nil {
return err
}
// Then create the same RC with the new name.
_, err = c.ReplicationControllers(rc.Namespace).Create(rc)
return err
}
type NewControllerConfig struct {
Namespace string
OldName, NewName string
Image string
Container string
DeploymentKey string
PullPolicy api.PullPolicy
}
type updateRcFunc func(controller *api.ReplicationController)
// updateRcWithRetries retries updating the given rc on conflict with the following steps:
// 1. Get latest resource
// 2. applyUpdate
// 3. Update the resource
func updateRcWithRetries(rcClient coreclient.ReplicationControllersGetter, namespace string, rc *api.ReplicationController, applyUpdate updateRcFunc) (*api.ReplicationController, error) {
// Deep copy the rc in case we failed on Get during retry loop
oldRc := rc.DeepCopy()
err := retry.RetryOnConflict(retry.DefaultBackoff, func() (e error) {
// Apply the update, then attempt to push it to the apiserver.
applyUpdate(rc)
if rc, e = rcClient.ReplicationControllers(namespace).Update(rc); e == nil {
// rc contains the latest controller post update
return
}
updateErr := e
// Update the controller with the latest resource version, if the update failed we
// can't trust rc so use oldRc.Name.
if rc, e = rcClient.ReplicationControllers(namespace).Get(oldRc.Name, metav1.GetOptions{}); e != nil {
// The Get failed: Value in rc cannot be trusted.
rc = oldRc
}
// Only return the error from update
return updateErr
})
// If the error is non-nil the returned controller cannot be trusted, if it is nil, the returned
// controller contains the applied update.
return rc, err
}