forked from kubernetes/kubernetes
-
Notifications
You must be signed in to change notification settings - Fork 0
/
helpers.go
302 lines (270 loc) · 8.65 KB
/
helpers.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
/*
Copyright 2014 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 util
import (
"bytes"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"os"
"strconv"
"strings"
"time"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api/latest"
"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
"github.com/GoogleCloudPlatform/kubernetes/pkg/client/clientcmd"
"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
utilerrors "github.com/GoogleCloudPlatform/kubernetes/pkg/util/errors"
"github.com/evanphx/json-patch"
"github.com/golang/glog"
"github.com/spf13/cobra"
"github.com/spf13/pflag"
)
type debugError interface {
DebugError() (msg string, args []interface{})
}
// CheckErr prints a user friendly error to STDERR and exits with a non-zero
// exit code. Unrecognized errors will be printed with an "error: " prefix.
//
// This method is generic to the command in use and may be used by non-Kubectl
// commands.
func CheckErr(err error) {
if err == nil {
return
}
// handle multiline errors
if clientcmd.IsConfigurationInvalid(err) {
fatal(MultilineError("Error in configuration: ", err))
}
if agg, ok := err.(utilerrors.Aggregate); ok && len(agg.Errors()) > 0 {
fatal(MultipleErrors("", agg.Errors()))
}
msg, ok := StandardErrorMessage(err)
if !ok {
msg = fmt.Sprintf("error: %s\n", err.Error())
}
fatal(msg)
}
// StandardErrorMessage translates common errors into a human readable message, or returns
// false if the error is not one of the recognized types. It may also log extended
// information to glog.
//
// This method is generic to the command in use and may be used by non-Kubectl
// commands.
func StandardErrorMessage(err error) (string, bool) {
if debugErr, ok := err.(debugError); ok {
glog.V(4).Infof(debugErr.DebugError())
}
_, isStatus := err.(client.APIStatus)
switch {
case isStatus:
return fmt.Sprintf("Error from server: %s", err.Error()), true
case errors.IsUnexpectedObjectError(err):
return fmt.Sprintf("Server returned an unexpected response: %s", err.Error()), true
}
switch t := err.(type) {
case *url.Error:
glog.V(4).Infof("Connection error: %s %s: %v", t.Op, t.URL, t.Err)
switch {
case strings.Contains(t.Err.Error(), "connection refused"):
host := t.URL
if server, err := url.Parse(t.URL); err == nil {
host = server.Host
}
return fmt.Sprintf("The connection to the server %s was refused - did you specify the right host or port?", host), true
}
return fmt.Sprintf("Unable to connect to the server: %v", t.Err), true
}
return "", false
}
// MultilineError returns a string representing an error that splits sub errors into their own
// lines. The returned string will end with a newline.
func MultilineError(prefix string, err error) string {
if agg, ok := err.(utilerrors.Aggregate); ok {
errs := utilerrors.Flatten(agg).Errors()
buf := &bytes.Buffer{}
switch len(errs) {
case 0:
return fmt.Sprintf("%s%v\n", prefix, err)
case 1:
return fmt.Sprintf("%s%v\n", prefix, messageForError(errs[0]))
default:
fmt.Fprintln(buf, prefix)
for _, err := range errs {
fmt.Fprintf(buf, "* %v\n", messageForError(err))
}
return buf.String()
}
}
return fmt.Sprintf("%s%s\n", prefix, err)
}
// MultipleErrors returns a newline delimited string containing
// the prefix and referenced errors in standard form.
func MultipleErrors(prefix string, errs []error) string {
buf := &bytes.Buffer{}
for _, err := range errs {
fmt.Fprintf(buf, "%s%v\n", prefix, messageForError(err))
}
return buf.String()
}
// messageForError returns the string representing the error.
func messageForError(err error) string {
msg, ok := StandardErrorMessage(err)
if !ok {
msg = err.Error()
}
return msg
}
// fatal prints the message and then exits. If V(2) or greater, glog.Fatal
// is invoked for extended information.
func fatal(msg string) {
// add newline if needed
if !strings.HasSuffix(msg, "\n") {
msg += "\n"
}
if glog.V(2) {
glog.FatalDepth(2, msg)
}
fmt.Fprint(os.Stderr, msg)
os.Exit(1)
}
func UsageError(cmd *cobra.Command, format string, args ...interface{}) error {
msg := fmt.Sprintf(format, args...)
return fmt.Errorf("%s\nsee '%s -h' for help.", msg, cmd.CommandPath())
}
func getFlag(cmd *cobra.Command, flag string) *pflag.Flag {
f := cmd.Flags().Lookup(flag)
if f == nil {
glog.Fatalf("flag accessed but not defined for command %s: %s", cmd.Name(), flag)
}
return f
}
func GetFlagString(cmd *cobra.Command, flag string) string {
f := getFlag(cmd, flag)
return f.Value.String()
}
func GetFlagBool(cmd *cobra.Command, flag string) bool {
f := getFlag(cmd, flag)
result, err := strconv.ParseBool(f.Value.String())
if err != nil {
glog.Fatalf("Invalid value for a boolean flag: %s", f.Value.String())
}
return result
}
// Assumes the flag has a default value.
func GetFlagInt(cmd *cobra.Command, flag string) int {
f := getFlag(cmd, flag)
v, err := strconv.Atoi(f.Value.String())
// This is likely not a sufficiently friendly error message, but cobra
// should prevent non-integer values from reaching here.
if err != nil {
glog.Fatalf("unable to convert flag value to int: %v", err)
}
return v
}
func GetFlagDuration(cmd *cobra.Command, flag string) time.Duration {
f := getFlag(cmd, flag)
v, err := time.ParseDuration(f.Value.String())
if err != nil {
glog.Fatalf("unable to convert flag value to Duration: %v", err)
}
return v
}
func ReadConfigDataFromReader(reader io.Reader, source string) ([]byte, error) {
data, err := ioutil.ReadAll(reader)
if err != nil {
return nil, err
}
if len(data) == 0 {
return nil, fmt.Errorf(`Read from %s but no data found`, source)
}
return data, nil
}
// ReadConfigData reads the bytes from the specified filesytem or network
// location or from stdin if location == "-".
// TODO: replace with resource.Builder
func ReadConfigData(location string) ([]byte, error) {
if len(location) == 0 {
return nil, fmt.Errorf("location given but empty")
}
if location == "-" {
// Read from stdin.
return ReadConfigDataFromReader(os.Stdin, "stdin ('-')")
}
// Use the location as a file path or URL.
return ReadConfigDataFromLocation(location)
}
// TODO: replace with resource.Builder
func ReadConfigDataFromLocation(location string) ([]byte, error) {
// we look for http:// or https:// to determine if valid URL, otherwise do normal file IO
if strings.Index(location, "http://") == 0 || strings.Index(location, "https://") == 0 {
resp, err := http.Get(location)
if err != nil {
return nil, fmt.Errorf("unable to access URL %s: %v\n", location, err)
}
defer resp.Body.Close()
if resp.StatusCode != 200 {
return nil, fmt.Errorf("unable to read URL, server reported %d %s", resp.StatusCode, resp.Status)
}
return ReadConfigDataFromReader(resp.Body, location)
} else {
file, err := os.Open(location)
if err != nil {
return nil, fmt.Errorf("unable to read %s: %v\n", location, err)
}
return ReadConfigDataFromReader(file, location)
}
}
func Merge(dst runtime.Object, fragment, kind string) (runtime.Object, error) {
// Ok, this is a little hairy, we'd rather not force the user to specify a kind for their JSON
// So we pull it into a map, add the Kind field, and then reserialize.
// We also pull the apiVersion for proper parsing
var intermediate interface{}
if err := json.Unmarshal([]byte(fragment), &intermediate); err != nil {
return nil, err
}
dataMap, ok := intermediate.(map[string]interface{})
if !ok {
return nil, fmt.Errorf("Expected a map, found something else: %s", fragment)
}
version, found := dataMap["apiVersion"]
if !found {
return nil, fmt.Errorf("Inline JSON requires an apiVersion field")
}
versionString, ok := version.(string)
if !ok {
return nil, fmt.Errorf("apiVersion must be a string")
}
i, err := latest.InterfacesFor(versionString)
if err != nil {
return nil, err
}
// encode dst into versioned json and apply fragment directly too it
target, err := i.Codec.Encode(dst)
if err != nil {
return nil, err
}
patched, err := jsonpatch.MergePatch(target, []byte(fragment))
if err != nil {
return nil, err
}
out, err := i.Codec.Decode(patched)
if err != nil {
return nil, err
}
return out, nil
}