-
Notifications
You must be signed in to change notification settings - Fork 39.2k
/
kube_docker_client.go
565 lines (509 loc) · 17.4 KB
/
kube_docker_client.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
/*
Copyright 2016 The Kubernetes Authors All rights reserved.
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 dockertools
import (
"bytes"
"encoding/base64"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"sync"
"time"
"github.com/golang/glog"
dockermessage "github.com/docker/docker/pkg/jsonmessage"
dockerstdcopy "github.com/docker/docker/pkg/stdcopy"
dockerapi "github.com/docker/engine-api/client"
dockertypes "github.com/docker/engine-api/types"
"golang.org/x/net/context"
)
// kubeDockerClient is a wrapped layer of docker client for kubelet internal use. This layer is added to:
// 1) Redirect stream for exec and attach operations.
// 2) Wrap the context in this layer to make the DockerInterface cleaner.
// 3) Stabilize the DockerInterface. The engine-api is still under active development, the interface
// is not stabilized yet. However, the DockerInterface is used in many files in Kubernetes, we may
// not want to change the interface frequently. With this layer, we can port the engine api to the
// DockerInterface to avoid changing DockerInterface as much as possible.
// (See
// * https://github.com/docker/engine-api/issues/89
// * https://github.com/docker/engine-api/issues/137
// * https://github.com/docker/engine-api/pull/140)
// TODO(random-liu): Swith to new docker interface by refactoring the functions in the old DockerInterface
// one by one.
type kubeDockerClient struct {
// timeout is the timeout of short running docker operations.
timeout time.Duration
client *dockerapi.Client
}
// Make sure that kubeDockerClient implemented the DockerInterface.
var _ DockerInterface = &kubeDockerClient{}
// There are 2 kinds of docker operations categorized by running time:
// * Long running operation: The long running operation could run for arbitrary long time, and the running time
// usually depends on some uncontrollable factors. These operations include: PullImage, Logs, StartExec, AttachToContainer.
// * Non-long running operation: Given the maximum load of the system, the non-long running operation should finish
// in expected and usually short time. These include all other operations.
// kubeDockerClient only applies timeout on non-long running operations.
const (
// defaultTimeout is the default timeout of short running docker operations.
defaultTimeout = 2 * time.Minute
// defaultShmSize is the default ShmSize to use (in bytes) if not specified.
defaultShmSize = int64(1024 * 1024 * 64)
// defaultImagePullingProgressReportInterval is the default interval of image pulling progress reporting.
defaultImagePullingProgressReportInterval = 10 * time.Second
// defaultImagePullingStuckTimeout is the default timeout for image pulling stuck. If no progress
// is made for defaultImagePullingStuckTimeout, the image pulling will be cancelled.
// Docker reports image progress for every 512kB block, so normally there shouldn't be too long interval
// between progress updates.
// TODO(random-liu): Make this configurable
defaultImagePullingStuckTimeout = 1 * time.Minute
)
// newKubeDockerClient creates an kubeDockerClient from an existing docker client. If requestTimeout is 0,
// defaultTimeout will be applied.
func newKubeDockerClient(dockerClient *dockerapi.Client, requestTimeout time.Duration) DockerInterface {
if requestTimeout == 0 {
requestTimeout = defaultTimeout
}
return &kubeDockerClient{
client: dockerClient,
timeout: requestTimeout,
}
}
func (d *kubeDockerClient) ListContainers(options dockertypes.ContainerListOptions) ([]dockertypes.Container, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
containers, err := d.client.ContainerList(ctx, options)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return containers, nil
}
func (d *kubeDockerClient) InspectContainer(id string) (*dockertypes.ContainerJSON, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
containerJSON, err := d.client.ContainerInspect(ctx, id)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
if dockerapi.IsErrContainerNotFound(err) {
return nil, containerNotFoundError{ID: id}
}
return nil, err
}
return &containerJSON, nil
}
func (d *kubeDockerClient) CreateContainer(opts dockertypes.ContainerCreateConfig) (*dockertypes.ContainerCreateResponse, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
// we provide an explicit default shm size as to not depend on docker daemon.
// TODO: evaluate exposing this as a knob in the API
if opts.HostConfig != nil && opts.HostConfig.ShmSize <= 0 {
opts.HostConfig.ShmSize = defaultShmSize
}
createResp, err := d.client.ContainerCreate(ctx, opts.Config, opts.HostConfig, opts.NetworkingConfig, opts.Name)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return &createResp, nil
}
func (d *kubeDockerClient) StartContainer(id string) error {
ctx, cancel := d.getTimeoutContext()
defer cancel()
err := d.client.ContainerStart(ctx, id)
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
return err
}
// Stopping an already stopped container will not cause an error in engine-api.
func (d *kubeDockerClient) StopContainer(id string, timeout int) error {
ctx, cancel := d.getTimeoutContext()
defer cancel()
err := d.client.ContainerStop(ctx, id, timeout)
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
return err
}
func (d *kubeDockerClient) RemoveContainer(id string, opts dockertypes.ContainerRemoveOptions) error {
ctx, cancel := d.getTimeoutContext()
defer cancel()
err := d.client.ContainerRemove(ctx, id, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
return err
}
func (d *kubeDockerClient) InspectImage(image string) (*dockertypes.ImageInspect, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, _, err := d.client.ImageInspectWithRaw(ctx, image, true)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
if dockerapi.IsErrImageNotFound(err) {
err = imageNotFoundError{ID: image}
}
return nil, err
}
return &resp, nil
}
func (d *kubeDockerClient) ImageHistory(id string) ([]dockertypes.ImageHistory, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, err := d.client.ImageHistory(ctx, id)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
return resp, err
}
func (d *kubeDockerClient) ListImages(opts dockertypes.ImageListOptions) ([]dockertypes.Image, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
images, err := d.client.ImageList(ctx, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return images, nil
}
func base64EncodeAuth(auth dockertypes.AuthConfig) (string, error) {
var buf bytes.Buffer
if err := json.NewEncoder(&buf).Encode(auth); err != nil {
return "", err
}
return base64.URLEncoding.EncodeToString(buf.Bytes()), nil
}
// progress is a wrapper of dockermessage.JSONMessage with a lock protecting it.
type progress struct {
sync.RWMutex
// message stores the latest docker json message.
message *dockermessage.JSONMessage
// timestamp of the latest update.
timestamp time.Time
}
func newProgress() *progress {
return &progress{timestamp: time.Now()}
}
func (p *progress) set(msg *dockermessage.JSONMessage) {
p.Lock()
defer p.Unlock()
p.message = msg
p.timestamp = time.Now()
}
func (p *progress) get() (string, time.Time) {
p.RLock()
defer p.RUnlock()
if p.message == nil {
return "No progress", p.timestamp
}
// The following code is based on JSONMessage.Display
var prefix string
if p.message.ID != "" {
prefix = fmt.Sprintf("%s: ", p.message.ID)
}
if p.message.Progress == nil {
return fmt.Sprintf("%s%s", prefix, p.message.Status), p.timestamp
}
return fmt.Sprintf("%s%s %s", prefix, p.message.Status, p.message.Progress.String()), p.timestamp
}
// progressReporter keeps the newest image pulling progress and periodically report the newest progress.
type progressReporter struct {
*progress
image string
cancel context.CancelFunc
stopCh chan struct{}
}
// newProgressReporter creates a new progressReporter for specific image with specified reporting interval
func newProgressReporter(image string, cancel context.CancelFunc) *progressReporter {
return &progressReporter{
progress: newProgress(),
image: image,
cancel: cancel,
stopCh: make(chan struct{}),
}
}
// start starts the progressReporter
func (p *progressReporter) start() {
go func() {
ticker := time.NewTicker(defaultImagePullingProgressReportInterval)
defer ticker.Stop()
for {
// TODO(random-liu): Report as events.
select {
case <-ticker.C:
progress, timestamp := p.progress.get()
// If there is no progress for defaultImagePullingStuckTimeout, cancel the operation.
if time.Now().Sub(timestamp) > defaultImagePullingStuckTimeout {
glog.Errorf("Cancel pulling image %q because of no progress for %v, latest progress: %q", p.image, defaultImagePullingStuckTimeout, progress)
p.cancel()
return
}
glog.V(2).Infof("Pulling image %q: %q", p.image, progress)
case <-p.stopCh:
progress, _ := p.progress.get()
glog.V(2).Infof("Stop pulling image %q: %q", p.image, progress)
return
}
}
}()
}
// stop stops the progressReporter
func (p *progressReporter) stop() {
close(p.stopCh)
}
func (d *kubeDockerClient) PullImage(image string, auth dockertypes.AuthConfig, opts dockertypes.ImagePullOptions) error {
// RegistryAuth is the base64 encoded credentials for the registry
base64Auth, err := base64EncodeAuth(auth)
if err != nil {
return err
}
opts.RegistryAuth = base64Auth
ctx, cancel := d.getCancelableContext()
defer cancel()
resp, err := d.client.ImagePull(ctx, image, opts)
if err != nil {
return err
}
defer resp.Close()
reporter := newProgressReporter(image, cancel)
reporter.start()
defer reporter.stop()
decoder := json.NewDecoder(resp)
for {
var msg dockermessage.JSONMessage
err := decoder.Decode(&msg)
if err == io.EOF {
break
}
if err != nil {
return err
}
if msg.Error != nil {
return msg.Error
}
reporter.set(&msg)
}
return nil
}
func (d *kubeDockerClient) RemoveImage(image string, opts dockertypes.ImageRemoveOptions) ([]dockertypes.ImageDelete, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, err := d.client.ImageRemove(ctx, image, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
return resp, err
}
func (d *kubeDockerClient) Logs(id string, opts dockertypes.ContainerLogsOptions, sopts StreamOptions) error {
ctx, cancel := d.getCancelableContext()
defer cancel()
resp, err := d.client.ContainerLogs(ctx, id, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
if err != nil {
return err
}
defer resp.Close()
return d.redirectResponseToOutputStream(sopts.RawTerminal, sopts.OutputStream, sopts.ErrorStream, resp)
}
func (d *kubeDockerClient) Version() (*dockertypes.Version, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, err := d.client.ServerVersion(ctx)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return &resp, nil
}
func (d *kubeDockerClient) Info() (*dockertypes.Info, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, err := d.client.Info(ctx)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return &resp, nil
}
// TODO(random-liu): Add unit test for exec and attach functions, just like what go-dockerclient did.
func (d *kubeDockerClient) CreateExec(id string, opts dockertypes.ExecConfig) (*dockertypes.ContainerExecCreateResponse, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, err := d.client.ContainerExecCreate(ctx, id, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return &resp, nil
}
func (d *kubeDockerClient) StartExec(startExec string, opts dockertypes.ExecStartCheck, sopts StreamOptions) error {
ctx, cancel := d.getCancelableContext()
defer cancel()
if opts.Detach {
err := d.client.ContainerExecStart(ctx, startExec, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
return err
}
resp, err := d.client.ContainerExecAttach(ctx, startExec, dockertypes.ExecConfig{
Detach: opts.Detach,
Tty: opts.Tty,
})
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
if err != nil {
return err
}
defer resp.Close()
return d.holdHijackedConnection(sopts.RawTerminal || opts.Tty, sopts.InputStream, sopts.OutputStream, sopts.ErrorStream, resp)
}
func (d *kubeDockerClient) InspectExec(id string) (*dockertypes.ContainerExecInspect, error) {
ctx, cancel := d.getTimeoutContext()
defer cancel()
resp, err := d.client.ContainerExecInspect(ctx, id)
if ctxErr := contextError(ctx); ctxErr != nil {
return nil, ctxErr
}
if err != nil {
return nil, err
}
return &resp, nil
}
func (d *kubeDockerClient) AttachToContainer(id string, opts dockertypes.ContainerAttachOptions, sopts StreamOptions) error {
ctx, cancel := d.getCancelableContext()
defer cancel()
resp, err := d.client.ContainerAttach(ctx, id, opts)
if ctxErr := contextError(ctx); ctxErr != nil {
return ctxErr
}
if err != nil {
return err
}
defer resp.Close()
return d.holdHijackedConnection(sopts.RawTerminal, sopts.InputStream, sopts.OutputStream, sopts.ErrorStream, resp)
}
// redirectResponseToOutputStream redirect the response stream to stdout and stderr. When tty is true, all stream will
// only be redirected to stdout.
func (d *kubeDockerClient) redirectResponseToOutputStream(tty bool, outputStream, errorStream io.Writer, resp io.Reader) error {
if outputStream == nil {
outputStream = ioutil.Discard
}
if errorStream == nil {
errorStream = ioutil.Discard
}
var err error
if tty {
_, err = io.Copy(outputStream, resp)
} else {
_, err = dockerstdcopy.StdCopy(outputStream, errorStream, resp)
}
return err
}
// holdHijackedConnection hold the HijackedResponse, redirect the inputStream to the connection, and redirect the response
// stream to stdout and stderr. NOTE: If needed, we could also add context in this function.
func (d *kubeDockerClient) holdHijackedConnection(tty bool, inputStream io.Reader, outputStream, errorStream io.Writer, resp dockertypes.HijackedResponse) error {
receiveStdout := make(chan error)
if outputStream != nil || errorStream != nil {
go func() {
receiveStdout <- d.redirectResponseToOutputStream(tty, outputStream, errorStream, resp.Reader)
}()
}
stdinDone := make(chan struct{})
go func() {
if inputStream != nil {
io.Copy(resp.Conn, inputStream)
}
resp.CloseWrite()
close(stdinDone)
}()
select {
case err := <-receiveStdout:
return err
case <-stdinDone:
if outputStream != nil || errorStream != nil {
return <-receiveStdout
}
}
return nil
}
// getCancelableContext returns a new cancelable context. For long running requests without timeout, we use cancelable
// context to avoid potential resource leak, although the current implementation shouldn't leak resource.
func (d *kubeDockerClient) getCancelableContext() (context.Context, context.CancelFunc) {
return context.WithCancel(context.Background())
}
// getTimeoutContext returns a new context with default request timeout
func (d *kubeDockerClient) getTimeoutContext() (context.Context, context.CancelFunc) {
return context.WithTimeout(context.Background(), d.timeout)
}
// parseDockerTimestamp parses the timestamp returned by DockerInterface from string to time.Time
func parseDockerTimestamp(s string) (time.Time, error) {
// Timestamp returned by Docker is in time.RFC3339Nano format.
return time.Parse(time.RFC3339Nano, s)
}
// contextError checks the context, and returns error if the context is timeout.
func contextError(ctx context.Context) error {
if ctx.Err() == context.DeadlineExceeded {
return operationTimeout{err: ctx.Err()}
}
return ctx.Err()
}
// StreamOptions are the options used to configure the stream redirection
type StreamOptions struct {
RawTerminal bool
InputStream io.Reader
OutputStream io.Writer
ErrorStream io.Writer
}
// operationTimeout is the error returned when the docker operations are timeout.
type operationTimeout struct {
err error
}
func (e operationTimeout) Error() string {
return fmt.Sprintf("operation timeout: %v", e.err)
}
// containerNotFoundError is the error returned by InspectContainer when container not found. We
// add this error type for testability. We don't use the original error returned by engine-api
// because dockertypes.containerNotFoundError is private, we can't create and inject it in our test.
type containerNotFoundError struct {
ID string
}
func (e containerNotFoundError) Error() string {
return fmt.Sprintf("no such container: %q", e.ID)
}
// imageNotFoundError is the error returned by InspectImage when image not found.
type imageNotFoundError struct {
ID string
}
func (e imageNotFoundError) Error() string {
return fmt.Sprintf("no such image: %q", e.ID)
}