-
Notifications
You must be signed in to change notification settings - Fork 39.2k
/
portforward.go
284 lines (241 loc) · 8.2 KB
/
portforward.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
/*
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 cmd
import (
"fmt"
"net/http"
"net/url"
"os"
"os/signal"
"strconv"
"strings"
"time"
"github.com/spf13/cobra"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
restclient "k8s.io/client-go/rest"
"k8s.io/client-go/tools/portforward"
"k8s.io/client-go/transport/spdy"
"k8s.io/kubernetes/pkg/api/legacyscheme"
api "k8s.io/kubernetes/pkg/apis/core"
coreclient "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset/typed/core/internalversion"
"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
"k8s.io/kubernetes/pkg/kubectl/genericclioptions"
"k8s.io/kubernetes/pkg/kubectl/polymorphichelpers"
"k8s.io/kubernetes/pkg/kubectl/util"
"k8s.io/kubernetes/pkg/kubectl/util/i18n"
)
// PortForwardOptions contains all the options for running the port-forward cli command.
type PortForwardOptions struct {
Namespace string
PodName string
RESTClient *restclient.RESTClient
Config *restclient.Config
PodClient coreclient.PodsGetter
Ports []string
PortForwarder portForwarder
StopChannel chan struct{}
ReadyChannel chan struct{}
}
var (
portforwardLong = templates.LongDesc(i18n.T(`
Forward one or more local ports to a pod.
Use resource type/name such as deployment/mydeployment to select a pod. Resource type defaults to 'pod' if omitted.
If there are multiple pods matching the criteria, a pod will be selected automatically. The
forwarding session ends when the selected pod terminates, and rerun of the command is needed
to resume forwarding.`))
portforwardExample = templates.Examples(i18n.T(`
# Listen on ports 5000 and 6000 locally, forwarding data to/from ports 5000 and 6000 in the pod
kubectl port-forward pod/mypod 5000 6000
# Listen on ports 5000 and 6000 locally, forwarding data to/from ports 5000 and 6000 in a pod selected by the deployment
kubectl port-forward deployment/mydeployment 5000 6000
# Listen on port 8888 locally, forwarding to 5000 in the pod
kubectl port-forward pod/mypod 8888:5000
# Listen on a random port locally, forwarding to 5000 in the pod
kubectl port-forward pod/mypod :5000`))
)
const (
// Amount of time to wait until at least one pod is running
defaultPodPortForwardWaitTimeout = 60 * time.Second
)
func NewCmdPortForward(f cmdutil.Factory, streams genericclioptions.IOStreams) *cobra.Command {
opts := &PortForwardOptions{
PortForwarder: &defaultPortForwarder{
IOStreams: streams,
},
}
cmd := &cobra.Command{
Use: "port-forward TYPE/NAME [LOCAL_PORT:]REMOTE_PORT [...[LOCAL_PORT_N:]REMOTE_PORT_N]",
DisableFlagsInUseLine: true,
Short: i18n.T("Forward one or more local ports to a pod"),
Long: portforwardLong,
Example: portforwardExample,
Run: func(cmd *cobra.Command, args []string) {
if err := opts.Complete(f, cmd, args); err != nil {
cmdutil.CheckErr(err)
}
if err := opts.Validate(); err != nil {
cmdutil.CheckErr(cmdutil.UsageErrorf(cmd, "%v", err.Error()))
}
if err := opts.RunPortForward(); err != nil {
cmdutil.CheckErr(err)
}
},
}
cmdutil.AddPodRunningTimeoutFlag(cmd, defaultPodPortForwardWaitTimeout)
// TODO support UID
return cmd
}
type portForwarder interface {
ForwardPorts(method string, url *url.URL, opts PortForwardOptions) error
}
type defaultPortForwarder struct {
genericclioptions.IOStreams
}
func (f *defaultPortForwarder) ForwardPorts(method string, url *url.URL, opts PortForwardOptions) error {
transport, upgrader, err := spdy.RoundTripperFor(opts.Config)
if err != nil {
return err
}
dialer := spdy.NewDialer(upgrader, &http.Client{Transport: transport}, method, url)
fw, err := portforward.New(dialer, opts.Ports, opts.StopChannel, opts.ReadyChannel, f.Out, f.ErrOut)
if err != nil {
return err
}
return fw.ForwardPorts()
}
// Translates service port to target port
// It rewrites ports as needed if the Service port declares targetPort.
// It returns an error when a named targetPort can't find a match in the pod, or the Service did not declare
// the port.
func translateServicePortToTargetPort(ports []string, svc api.Service, pod api.Pod) ([]string, error) {
var translated []string
for _, port := range ports {
// port is in the form of [LOCAL PORT]:REMOTE PORT
parts := strings.Split(port, ":")
input := parts[0]
if len(parts) == 2 {
input = parts[1]
}
portnum, err := strconv.Atoi(input)
if err != nil {
return ports, err
}
containerPort, err := util.LookupContainerPortNumberByServicePort(svc, pod, int32(portnum))
if err != nil {
// can't resolve a named port, or Service did not declare this port, return an error
return nil, err
} else {
if int32(portnum) != containerPort {
translated = append(translated, fmt.Sprintf("%s:%d", parts[0], containerPort))
} else {
translated = append(translated, port)
}
}
}
return translated, nil
}
// Complete completes all the required options for port-forward cmd.
func (o *PortForwardOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args []string) error {
var err error
if len(args) < 2 {
return cmdutil.UsageErrorf(cmd, "TYPE/NAME and list of ports are required for port-forward")
}
o.Namespace, _, err = f.ToRawKubeConfigLoader().Namespace()
if err != nil {
return err
}
builder := f.NewBuilder().
WithScheme(legacyscheme.Scheme).
ContinueOnError().
NamespaceParam(o.Namespace).DefaultNamespace()
getPodTimeout, err := cmdutil.GetPodRunningTimeoutFlag(cmd)
if err != nil {
return cmdutil.UsageErrorf(cmd, err.Error())
}
resourceName := args[0]
builder.ResourceNames("pods", resourceName)
obj, err := builder.Do().Object()
if err != nil {
return err
}
forwardablePod, err := polymorphichelpers.AttachablePodForObjectFn(f, obj, getPodTimeout)
if err != nil {
return err
}
o.PodName = forwardablePod.Name
// handle service port mapping to target port if needed
switch t := obj.(type) {
case *api.Service:
o.Ports, err = translateServicePortToTargetPort(args[1:], *t, *forwardablePod)
if err != nil {
return err
}
default:
o.Ports = args[1:]
}
clientset, err := f.ClientSet()
if err != nil {
return err
}
o.PodClient = clientset.Core()
o.Config, err = f.ToRESTConfig()
if err != nil {
return err
}
o.RESTClient, err = f.RESTClient()
if err != nil {
return err
}
o.StopChannel = make(chan struct{}, 1)
o.ReadyChannel = make(chan struct{})
return nil
}
// Validate validates all the required options for port-forward cmd.
func (o PortForwardOptions) Validate() error {
if len(o.PodName) == 0 {
return fmt.Errorf("pod name or resource type/name must be specified")
}
if len(o.Ports) < 1 {
return fmt.Errorf("at least 1 PORT is required for port-forward")
}
if o.PortForwarder == nil || o.PodClient == nil || o.RESTClient == nil || o.Config == nil {
return fmt.Errorf("client, client config, restClient, and portforwarder must be provided")
}
return nil
}
// RunPortForward implements all the necessary functionality for port-forward cmd.
func (o PortForwardOptions) RunPortForward() error {
pod, err := o.PodClient.Pods(o.Namespace).Get(o.PodName, metav1.GetOptions{})
if err != nil {
return err
}
if pod.Status.Phase != api.PodRunning {
return fmt.Errorf("unable to forward port because pod is not running. Current status=%v", pod.Status.Phase)
}
signals := make(chan os.Signal, 1)
signal.Notify(signals, os.Interrupt)
defer signal.Stop(signals)
go func() {
<-signals
if o.StopChannel != nil {
close(o.StopChannel)
}
}()
req := o.RESTClient.Post().
Resource("pods").
Namespace(o.Namespace).
Name(pod.Name).
SubResource("portforward")
return o.PortForwarder.ForwardPorts("POST", req.URL(), o)
}