forked from kubernetes/kubernetes
-
Notifications
You must be signed in to change notification settings - Fork 14
/
resource_printer.go
619 lines (567 loc) · 18.4 KB
/
resource_printer.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
/*
Copyright 2014 Google Inc. 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 kubectl
import (
"bytes"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"reflect"
"sort"
"strings"
"text/tabwriter"
"text/template"
"time"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
"github.com/ghodss/yaml"
"github.com/golang/glog"
)
// GetPrinter takes a format type, an optional format argument. It will return true
// if the format is generic (untyped), otherwise it will return false. The printer
// is agnostic to schema versions, so you must send arguments to PrintObj in the
// version you wish them to be shown using a VersionedPrinter (typically when
// generic is true).
func GetPrinter(format, formatArgument string) (ResourcePrinter, bool, error) {
var printer ResourcePrinter
switch format {
case "json":
printer = &JSONPrinter{}
case "yaml":
printer = &YAMLPrinter{}
case "template":
if len(formatArgument) == 0 {
return nil, false, fmt.Errorf("template format specified but no template given")
}
var err error
printer, err = NewTemplatePrinter([]byte(formatArgument))
if err != nil {
return nil, false, fmt.Errorf("error parsing template %s, %v\n", formatArgument, err)
}
case "templatefile":
if len(formatArgument) == 0 {
return nil, false, fmt.Errorf("templatefile format specified but no template file given")
}
data, err := ioutil.ReadFile(formatArgument)
if err != nil {
return nil, false, fmt.Errorf("error reading template %s, %v\n", formatArgument, err)
}
printer, err = NewTemplatePrinter(data)
if err != nil {
return nil, false, fmt.Errorf("error parsing template %s, %v\n", string(data), err)
}
case "":
return nil, false, nil
default:
return nil, false, fmt.Errorf("output format %q not recognized", format)
}
return printer, true, nil
}
// ResourcePrinter is an interface that knows how to print runtime objects.
type ResourcePrinter interface {
// Print receives a runtime object, formats it and prints it to a writer.
PrintObj(runtime.Object, io.Writer) error
}
// ResourcePrinterFunc is a function that can print objects
type ResourcePrinterFunc func(runtime.Object, io.Writer) error
// PrintObj implements ResourcePrinter
func (fn ResourcePrinterFunc) PrintObj(obj runtime.Object, w io.Writer) error {
return fn(obj, w)
}
// VersionedPrinter takes runtime objects and ensures they are converted to a given API version
// prior to being passed to a nested printer.
type VersionedPrinter struct {
printer ResourcePrinter
convertor runtime.ObjectConvertor
version string
}
// NewVersionedPrinter wraps a printer to convert objects to a known API version prior to printing.
func NewVersionedPrinter(printer ResourcePrinter, convertor runtime.ObjectConvertor, version string) ResourcePrinter {
return &VersionedPrinter{
printer: printer,
convertor: convertor,
version: version,
}
}
// PrintObj implements ResourcePrinter
func (p *VersionedPrinter) PrintObj(obj runtime.Object, w io.Writer) error {
if len(p.version) == 0 {
return fmt.Errorf("no version specified, object cannot be converted")
}
converted, err := p.convertor.ConvertToVersion(obj, p.version)
if err != nil {
return err
}
return p.printer.PrintObj(converted, w)
}
// JSONPrinter is an implementation of ResourcePrinter which outputs an object as JSON.
type JSONPrinter struct {
}
// PrintObj is an implementation of ResourcePrinter.PrintObj which simply writes the object to the Writer.
func (p *JSONPrinter) PrintObj(obj runtime.Object, w io.Writer) error {
data, err := json.Marshal(obj)
if err != nil {
return err
}
dst := bytes.Buffer{}
err = json.Indent(&dst, data, "", " ")
dst.WriteByte('\n')
_, err = w.Write(dst.Bytes())
return err
}
// YAMLPrinter is an implementation of ResourcePrinter which outputs an object as YAML.
// The input object is assumed to be in the internal version of an API and is converted
// to the given version first.
type YAMLPrinter struct {
version string
convertor runtime.ObjectConvertor
}
// PrintObj prints the data as YAML.
func (p *YAMLPrinter) PrintObj(obj runtime.Object, w io.Writer) error {
output, err := yaml.Marshal(obj)
if err != nil {
return err
}
_, err = fmt.Fprint(w, string(output))
return err
}
type handlerEntry struct {
columns []string
printFunc reflect.Value
}
// HumanReadablePrinter is an implementation of ResourcePrinter which attempts to provide
// more elegant output. It is not threadsafe, but you may call PrintObj repeatedly; headers
// will only be printed if the object type changes. This makes it useful for printing items
// recieved from watches.
type HumanReadablePrinter struct {
handlerMap map[reflect.Type]*handlerEntry
noHeaders bool
lastType reflect.Type
}
// NewHumanReadablePrinter creates a HumanReadablePrinter.
func NewHumanReadablePrinter(noHeaders bool) *HumanReadablePrinter {
printer := &HumanReadablePrinter{
handlerMap: make(map[reflect.Type]*handlerEntry),
noHeaders: noHeaders,
}
printer.addDefaultHandlers()
return printer
}
// Handler adds a print handler with a given set of columns to HumanReadablePrinter instance.
// printFunc is the function that will be called to print an object.
// It must be of the following type:
// func printFunc(object ObjectType, w io.Writer) error
// where ObjectType is the type of the object that will be printed.
func (h *HumanReadablePrinter) Handler(columns []string, printFunc interface{}) error {
printFuncValue := reflect.ValueOf(printFunc)
if err := h.validatePrintHandlerFunc(printFuncValue); err != nil {
glog.Errorf("Unable to add print handler: %v", err)
return err
}
objType := printFuncValue.Type().In(0)
h.handlerMap[objType] = &handlerEntry{
columns: columns,
printFunc: printFuncValue,
}
return nil
}
func (h *HumanReadablePrinter) validatePrintHandlerFunc(printFunc reflect.Value) error {
if printFunc.Kind() != reflect.Func {
return fmt.Errorf("invalid print handler. %#v is not a function.", printFunc)
}
funcType := printFunc.Type()
if funcType.NumIn() != 2 || funcType.NumOut() != 1 {
return fmt.Errorf("invalid print handler." +
"Must accept 2 parameters and return 1 value.")
}
if funcType.In(1) != reflect.TypeOf((*io.Writer)(nil)).Elem() ||
funcType.Out(0) != reflect.TypeOf((*error)(nil)).Elem() {
return fmt.Errorf("invalid print handler. The expected signature is: "+
"func handler(obj %v, w io.Writer) error", funcType.In(0))
}
return nil
}
var podColumns = []string{"POD", "IP", "CONTAINER(S)", "IMAGE(S)", "HOST", "LABELS", "STATUS"}
var replicationControllerColumns = []string{"CONTROLLER", "CONTAINER(S)", "IMAGE(S)", "SELECTOR", "REPLICAS"}
var serviceColumns = []string{"NAME", "LABELS", "SELECTOR", "IP", "PORT"}
var minionColumns = []string{"NAME", "LABELS", "STATUS"}
var statusColumns = []string{"STATUS"}
var eventColumns = []string{"TIME", "NAME", "KIND", "SUBOBJECT", "REASON", "SOURCE", "MESSAGE"}
var limitRangeColumns = []string{"NAME"}
var resourceQuotaColumns = []string{"NAME"}
// addDefaultHandlers adds print handlers for default Kubernetes types.
func (h *HumanReadablePrinter) addDefaultHandlers() {
h.Handler(podColumns, printPod)
h.Handler(podColumns, printPodList)
h.Handler(replicationControllerColumns, printReplicationController)
h.Handler(replicationControllerColumns, printReplicationControllerList)
h.Handler(serviceColumns, printService)
h.Handler(serviceColumns, printServiceList)
h.Handler(minionColumns, printMinion)
h.Handler(minionColumns, printMinionList)
h.Handler(statusColumns, printStatus)
h.Handler(eventColumns, printEvent)
h.Handler(eventColumns, printEventList)
h.Handler(limitRangeColumns, printLimitRange)
h.Handler(limitRangeColumns, printLimitRangeList)
h.Handler(resourceQuotaColumns, printResourceQuota)
h.Handler(resourceQuotaColumns, printResourceQuotaList)
}
func (h *HumanReadablePrinter) unknown(data []byte, w io.Writer) error {
_, err := fmt.Fprintf(w, "Unknown object: %s", string(data))
return err
}
func (h *HumanReadablePrinter) printHeader(columnNames []string, w io.Writer) error {
if _, err := fmt.Fprintf(w, "%s\n", strings.Join(columnNames, "\t")); err != nil {
return err
}
return nil
}
func podHostString(host, ip string) string {
if host == "" && ip == "" {
return "<unassigned>"
}
return host + "/" + ip
}
func printPod(pod *api.Pod, w io.Writer) error {
// TODO: remove me when pods are converted
spec := &api.PodSpec{}
if err := api.Scheme.Convert(&pod.Spec, spec); err != nil {
glog.Errorf("Unable to convert pod manifest: %v", err)
}
containers := spec.Containers
var firstContainer api.Container
if len(containers) > 0 {
firstContainer, containers = containers[0], containers[1:]
}
_, err := fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\t%s\t%s\n",
pod.Name,
pod.Status.PodIP,
firstContainer.Name,
firstContainer.Image,
podHostString(pod.Status.Host, pod.Status.HostIP),
formatLabels(pod.Labels),
pod.Status.Phase)
if err != nil {
return err
}
// Lay out all the other containers on separate lines.
for _, container := range containers {
_, err := fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\t%s\t%s\n", "", "", container.Name, container.Image, "", "", "")
if err != nil {
return err
}
}
return nil
}
func printPodList(podList *api.PodList, w io.Writer) error {
for _, pod := range podList.Items {
if err := printPod(&pod, w); err != nil {
return err
}
}
return nil
}
func printReplicationController(controller *api.ReplicationController, w io.Writer) error {
containers := controller.Spec.Template.Spec.Containers
var firstContainer api.Container
if len(containers) > 0 {
firstContainer, containers = containers[0], containers[1:]
}
_, err := fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%d\n",
controller.Name,
firstContainer.Name,
firstContainer.Image,
formatLabels(controller.Spec.Selector),
controller.Spec.Replicas)
if err != nil {
return err
}
// Lay out all the other containers on separate lines.
for _, container := range containers {
_, err := fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\n", "", container.Name, container.Image, "", "")
if err != nil {
return err
}
}
return nil
}
func printReplicationControllerList(list *api.ReplicationControllerList, w io.Writer) error {
for _, controller := range list.Items {
if err := printReplicationController(&controller, w); err != nil {
return err
}
}
return nil
}
func printService(svc *api.Service, w io.Writer) error {
_, err := fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%d\n", svc.Name, formatLabels(svc.Labels),
formatLabels(svc.Spec.Selector), svc.Spec.PortalIP, svc.Spec.Port)
return err
}
func printServiceList(list *api.ServiceList, w io.Writer) error {
for _, svc := range list.Items {
if err := printService(&svc, w); err != nil {
return err
}
}
return nil
}
func printMinion(minion *api.Node, w io.Writer) error {
conditionMap := make(map[api.NodeConditionKind]*api.NodeCondition)
NodeAllConditions := []api.NodeConditionKind{api.NodeReady, api.NodeReachable}
for i := range minion.Status.Conditions {
cond := minion.Status.Conditions[i]
conditionMap[cond.Kind] = &cond
}
var status []string
for _, validCondition := range NodeAllConditions {
if condition, ok := conditionMap[validCondition]; ok {
if condition.Status == api.ConditionFull {
status = append(status, string(condition.Kind))
} else {
status = append(status, "Not"+string(condition.Kind))
}
}
}
if len(status) == 0 {
status = append(status, "Unknown")
}
_, err := fmt.Fprintf(w, "%s\t%s\t%s\n", minion.Name, formatLabels(minion.Labels), strings.Join(status, ","))
return err
}
func printMinionList(list *api.NodeList, w io.Writer) error {
for _, minion := range list.Items {
if err := printMinion(&minion, w); err != nil {
return err
}
}
return nil
}
func printStatus(status *api.Status, w io.Writer) error {
_, err := fmt.Fprintf(w, "%v\n", status.Status)
return err
}
func printEvent(event *api.Event, w io.Writer) error {
_, err := fmt.Fprintf(
w, "%s\t%s\t%s\t%s\t%s\t%s\t%s\n",
event.Timestamp.Time.Format(time.RFC1123Z),
event.InvolvedObject.Name,
event.InvolvedObject.Kind,
event.InvolvedObject.FieldPath,
event.Reason,
event.Source,
event.Message,
)
return err
}
// Sorts and prints the EventList in a human-friendly format.
func printEventList(list *api.EventList, w io.Writer) error {
sort.Sort(SortableEvents(list.Items))
for i := range list.Items {
if err := printEvent(&list.Items[i], w); err != nil {
return err
}
}
return nil
}
func printLimitRange(limitRange *api.LimitRange, w io.Writer) error {
_, err := fmt.Fprintf(
w, "%s\n",
limitRange.Name,
)
return err
}
// Prints the LimitRangeList in a human-friendly format.
func printLimitRangeList(list *api.LimitRangeList, w io.Writer) error {
for i := range list.Items {
if err := printLimitRange(&list.Items[i], w); err != nil {
return err
}
}
return nil
}
func printResourceQuota(resourceQuota *api.ResourceQuota, w io.Writer) error {
_, err := fmt.Fprintf(
w, "%s\n",
resourceQuota.Name,
)
return err
}
// Prints the ResourceQuotaList in a human-friendly format.
func printResourceQuotaList(list *api.ResourceQuotaList, w io.Writer) error {
for i := range list.Items {
if err := printResourceQuota(&list.Items[i], w); err != nil {
return err
}
}
return nil
}
// PrintObj prints the obj in a human-friendly format according to the type of the obj.
func (h *HumanReadablePrinter) PrintObj(obj runtime.Object, output io.Writer) error {
w := tabwriter.NewWriter(output, 20, 5, 3, ' ', 0)
defer w.Flush()
t := reflect.TypeOf(obj)
if handler := h.handlerMap[t]; handler != nil {
if !h.noHeaders && t != h.lastType {
h.printHeader(handler.columns, w)
h.lastType = t
}
args := []reflect.Value{reflect.ValueOf(obj), reflect.ValueOf(w)}
resultValue := handler.printFunc.Call(args)[0]
if resultValue.IsNil() {
return nil
}
return resultValue.Interface().(error)
}
return fmt.Errorf("error: unknown type %#v", obj)
}
// TemplatePrinter is an implementation of ResourcePrinter which formats data with a Go Template.
type TemplatePrinter struct {
rawTemplate string
template *template.Template
}
func NewTemplatePrinter(tmpl []byte) (*TemplatePrinter, error) {
t, err := template.New("output").
Funcs(template.FuncMap{"exists": exists}).
Parse(string(tmpl))
if err != nil {
return nil, err
}
return &TemplatePrinter{
rawTemplate: string(tmpl),
template: t,
}, nil
}
// PrintObj formats the obj with the Go Template.
func (p *TemplatePrinter) PrintObj(obj runtime.Object, w io.Writer) error {
data, err := json.Marshal(obj)
if err != nil {
return err
}
out := map[string]interface{}{}
if err := json.Unmarshal(data, &out); err != nil {
return err
}
if err = p.safeExecute(w, out); err != nil {
// It is way easier to debug this stuff when it shows up in
// stdout instead of just stdin. So in addition to returning
// a nice error, also print useful stuff with the writer.
fmt.Fprintf(w, "Error executing template: %v\n", err)
fmt.Fprintf(w, "template was:\n\t%v\n", p.rawTemplate)
fmt.Fprintf(w, "raw data was:\n\t%v\n", string(data))
fmt.Fprintf(w, "object given to template engine was:\n\t%+v\n", out)
return fmt.Errorf("error executing template '%v': '%v'\n----data----\n%+v\n", p.rawTemplate, err, out)
}
return nil
}
// safeExecute tries to execute the template, but catches panics and returns an error
// should the template engine panic.
func (p *TemplatePrinter) safeExecute(w io.Writer, obj interface{}) error {
var panicErr error
// Sorry for the double anonymous function. There's probably a clever way
// to do this that has the defer'd func setting the value to be returned, but
// that would be even less obvious.
retErr := func() error {
defer func() {
if x := recover(); x != nil {
panicErr = fmt.Errorf("caught panic: %+v", x)
}
}()
return p.template.Execute(w, obj)
}()
if panicErr != nil {
return panicErr
}
return retErr
}
func tabbedString(f func(io.Writer) error) (string, error) {
out := new(tabwriter.Writer)
buf := &bytes.Buffer{}
out.Init(buf, 0, 8, 1, '\t', 0)
err := f(out)
if err != nil {
return "", err
}
out.Flush()
str := string(buf.String())
return str, nil
}
// exists returns true if it would be possible to call the index function
// with these arguments.
//
// TODO: how to document this for users?
//
// index returns the result of indexing its first argument by the following
// arguments. Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each
// indexed item must be a map, slice, or array.
func exists(item interface{}, indices ...interface{}) bool {
v := reflect.ValueOf(item)
for _, i := range indices {
index := reflect.ValueOf(i)
var isNil bool
if v, isNil = indirect(v); isNil {
return false
}
switch v.Kind() {
case reflect.Array, reflect.Slice, reflect.String:
var x int64
switch index.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
x = index.Int()
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
x = int64(index.Uint())
default:
return false
}
if x < 0 || x >= int64(v.Len()) {
return false
}
v = v.Index(int(x))
case reflect.Map:
if !index.IsValid() {
index = reflect.Zero(v.Type().Key())
}
if !index.Type().AssignableTo(v.Type().Key()) {
return false
}
if x := v.MapIndex(index); x.IsValid() {
v = x
} else {
v = reflect.Zero(v.Type().Elem())
}
default:
return false
}
}
if _, isNil := indirect(v); isNil {
return false
}
return true
}
// stolen from text/template
// indirect returns the item at the end of indirection, and a bool to indicate if it's nil.
// We indirect through pointers and empty interfaces (only) because
// non-empty interfaces have methods we might need.
func indirect(v reflect.Value) (rv reflect.Value, isNil bool) {
for ; v.Kind() == reflect.Ptr || v.Kind() == reflect.Interface; v = v.Elem() {
if v.IsNil() {
return v, true
}
if v.Kind() == reflect.Interface && v.NumMethod() > 0 {
break
}
}
return v, false
}