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Merge pull request #11999 from brendandburns/attach2

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Add support for attach to kubectl
This commit is contained in:
Mike Danese
2015-07-31 12:51:08 -07:00
parent 066237e62a 97cb1cd071
commit a23ee556ad
25 changed files with 1257 additions and 43 deletions
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211
pkg/kubectl/cmd/attach.go Normal file
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@@ -0,0 +1,211 @@
/*
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 cmd
import (
"fmt"
"io"
"os"
"os/signal"
"syscall"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
"github.com/GoogleCloudPlatform/kubernetes/pkg/client/remotecommand"
cmdutil "github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/cmd/util"
"github.com/docker/docker/pkg/term"
"github.com/golang/glog"
"github.com/spf13/cobra"
)
const (
attach_example = `// get output from running pod 123456-7890, using the first container by default
$ kubectl attach 123456-7890
// get output from ruby-container from pod 123456-7890
$ kubectl attach 123456-7890 -c ruby-container date
// switch to raw terminal mode, sends stdin to 'bash' in ruby-container from pod 123456-780
// and sends stdout/stderr from 'bash' back to the client
$ kubectl attach 123456-7890 -c ruby-container -i -t`
)
func NewCmdAttach(f *cmdutil.Factory, cmdIn io.Reader, cmdOut, cmdErr io.Writer) *cobra.Command {
options := &AttachOptions{
In: cmdIn,
Out: cmdOut,
Err: cmdErr,
Attach: &DefaultRemoteAttach{},
}
cmd := &cobra.Command{
Use: "attach POD -c CONTAINER",
Short: "Attach to a running container.",
Long: "Attach to a a process that is already running inside an existing container.",
Example: attach_example,
Run: func(cmd *cobra.Command, args []string) {
cmdutil.CheckErr(options.Complete(f, cmd, args))
cmdutil.CheckErr(options.Validate())
cmdutil.CheckErr(options.Run())
},
}
// TODO support UID
cmd.Flags().StringVarP(&options.ContainerName, "container", "c", "", "Container name")
cmd.Flags().BoolVarP(&options.Stdin, "stdin", "i", false, "Pass stdin to the container")
cmd.Flags().BoolVarP(&options.TTY, "tty", "t", false, "Stdin is a TTY")
return cmd
}
// RemoteAttach defines the interface accepted by the Attach command - provided for test stubbing
type RemoteAttach interface {
Attach(req *client.Request, config *client.Config, stdin io.Reader, stdout, stderr io.Writer, tty bool) error
}
// DefaultRemoteAttach is the standard implementation of attaching
type DefaultRemoteAttach struct{}
func (*DefaultRemoteAttach) Attach(req *client.Request, config *client.Config, stdin io.Reader, stdout, stderr io.Writer, tty bool) error {
attach := remotecommand.NewAttach(req, config, stdin, stdout, stderr, tty)
return attach.Execute()
}
// AttachOptions declare the arguments accepted by the Exec command
type AttachOptions struct {
Namespace string
PodName string
ContainerName string
Stdin bool
TTY bool
In io.Reader
Out io.Writer
Err io.Writer
Attach RemoteAttach
Client *client.Client
Config *client.Config
}
// Complete verifies command line arguments and loads data from the command environment
func (p *AttachOptions) Complete(f *cmdutil.Factory, cmd *cobra.Command, argsIn []string) error {
if len(argsIn) == 0 {
return cmdutil.UsageError(cmd, "POD is required for attach")
}
if len(argsIn) > 1 {
return cmdutil.UsageError(cmd, fmt.Sprintf("expected a single argument: POD, saw %d: %s", len(argsIn), argsIn))
}
p.PodName = argsIn[0]
namespace, _, err := f.DefaultNamespace()
if err != nil {
return err
}
p.Namespace = namespace
config, err := f.ClientConfig()
if err != nil {
return err
}
p.Config = config
client, err := f.Client()
if err != nil {
return err
}
p.Client = client
return nil
}
// Validate checks that the provided attach options are specified.
func (p *AttachOptions) Validate() error {
if len(p.PodName) == 0 {
return fmt.Errorf("pod name must be specified")
}
if p.Out == nil || p.Err == nil {
return fmt.Errorf("both output and error output must be provided")
}
if p.Attach == nil || p.Client == nil || p.Config == nil {
return fmt.Errorf("client, client config, and attach must be provided")
}
return nil
}
// Run executes a validated remote execution against a pod.
func (p *AttachOptions) Run() error {
pod, err := p.Client.Pods(p.Namespace).Get(p.PodName)
if err != nil {
return err
}
if pod.Status.Phase != api.PodRunning {
return fmt.Errorf("pod %s is not running and cannot be attached to; current phase is %s", p.PodName, pod.Status.Phase)
}
containerName := p.ContainerName
if len(containerName) == 0 {
glog.V(4).Infof("defaulting container name to %s", pod.Spec.Containers[0].Name)
containerName = pod.Spec.Containers[0].Name
}
// TODO: refactor with terminal helpers from the edit utility once that is merged
var stdin io.Reader
tty := p.TTY
if p.Stdin {
stdin = p.In
if tty {
if file, ok := stdin.(*os.File); ok {
inFd := file.Fd()
if term.IsTerminal(inFd) {
oldState, err := term.SetRawTerminal(inFd)
if err != nil {
glog.Fatal(err)
}
// this handles a clean exit, where the command finished
defer term.RestoreTerminal(inFd, oldState)
// SIGINT is handled by term.SetRawTerminal (it runs a goroutine that listens
// for SIGINT and restores the terminal before exiting)
// this handles SIGTERM
sigChan := make(chan os.Signal, 1)
signal.Notify(sigChan, syscall.SIGTERM)
go func() {
<-sigChan
term.RestoreTerminal(inFd, oldState)
os.Exit(0)
}()
} else {
fmt.Fprintln(p.Err, "STDIN is not a terminal")
}
} else {
tty = false
fmt.Fprintln(p.Err, "Unable to use a TTY - input is not the right kind of file")
}
}
}
// TODO: consider abstracting into a client invocation or client helper
req := p.Client.RESTClient.Post().
Resource("pods").
Name(pod.Name).
Namespace(pod.Namespace).
SubResource("attach").
Param("container", containerName)
return p.Attach.Attach(req, p.Config, stdin, p.Out, p.Err, tty)
}

198
pkg/kubectl/cmd/attach_test.go Normal file
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@@ -0,0 +1,198 @@
/*
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 cmd
import (
"bytes"
"fmt"
"io"
"net/http"
"testing"
"github.com/spf13/cobra"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api/testapi"
"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
)
type fakeRemoteAttach struct {
req *client.Request
attachErr error
}
func (f *fakeRemoteAttach) Attach(req *client.Request, config *client.Config, stdin io.Reader, stdout, stderr io.Writer, tty bool) error {
f.req = req
return f.attachErr
}
func TestPodAndContainerAttach(t *testing.T) {
tests := []struct {
args []string
p *AttachOptions
name string
expectError bool
expectedPod string
expectedContainer string
}{
{
p: &AttachOptions{},
expectError: true,
name: "empty",
},
{
p: &AttachOptions{},
args: []string{"foo", "bar"},
expectError: true,
name: "too many args",
},
{
p: &AttachOptions{},
args: []string{"foo"},
expectedPod: "foo",
name: "no container, no flags",
},
{
p: &AttachOptions{ContainerName: "bar"},
args: []string{"foo"},
expectedPod: "foo",
expectedContainer: "bar",
name: "container in flag",
},
}
for _, test := range tests {
f, tf, codec := NewAPIFactory()
tf.Client = &client.FakeRESTClient{
Codec: codec,
Client: client.HTTPClientFunc(func(req *http.Request) (*http.Response, error) { return nil, nil }),
}
tf.Namespace = "test"
tf.ClientConfig = &client.Config{}
cmd := &cobra.Command{}
options := test.p
err := options.Complete(f, cmd, test.args)
if test.expectError && err == nil {
t.Errorf("unexpected non-error (%s)", test.name)
}
if !test.expectError && err != nil {
t.Errorf("unexpected error: %v (%s)", err, test.name)
}
if err != nil {
continue
}
if options.PodName != test.expectedPod {
t.Errorf("expected: %s, got: %s (%s)", test.expectedPod, options.PodName, test.name)
}
if options.ContainerName != test.expectedContainer {
t.Errorf("expected: %s, got: %s (%s)", test.expectedContainer, options.ContainerName, test.name)
}
}
}
func TestAttach(t *testing.T) {
version := testapi.Version()
tests := []struct {
name, version, podPath, attachPath, container string
pod *api.Pod
attachErr bool
}{
{
name: "pod attach",
version: version,
podPath: "/api/" + version + "/namespaces/test/pods/foo",
attachPath: "/api/" + version + "/namespaces/test/pods/foo/attach",
pod: attachPod(),
},
{
name: "pod attach error",
version: version,
podPath: "/api/" + version + "/namespaces/test/pods/foo",
attachPath: "/api/" + version + "/namespaces/test/pods/foo/attach",
pod: attachPod(),
attachErr: true,
},
}
for _, test := range tests {
f, tf, codec := NewAPIFactory()
tf.Client = &client.FakeRESTClient{
Codec: codec,
Client: client.HTTPClientFunc(func(req *http.Request) (*http.Response, error) {
switch p, m := req.URL.Path, req.Method; {
case p == test.podPath && m == "GET":
body := objBody(codec, test.pod)
return &http.Response{StatusCode: 200, Body: body}, nil
default:
// Ensures no GET is performed when deleting by name
t.Errorf("%s: unexpected request: %s %#v\n%#v", test.name, req.Method, req.URL, req)
return nil, fmt.Errorf("unexpected request")
}
}),
}
tf.Namespace = "test"
tf.ClientConfig = &client.Config{Version: test.version}
bufOut := bytes.NewBuffer([]byte{})
bufErr := bytes.NewBuffer([]byte{})
bufIn := bytes.NewBuffer([]byte{})
ex := &fakeRemoteAttach{}
if test.attachErr {
ex.attachErr = fmt.Errorf("attach error")
}
params := &AttachOptions{
ContainerName: "bar",
In: bufIn,
Out: bufOut,
Err: bufErr,
Attach: ex,
}
cmd := &cobra.Command{}
if err := params.Complete(f, cmd, []string{"foo"}); err != nil {
t.Fatal(err)
}
err := params.Run()
if test.attachErr && err != ex.attachErr {
t.Errorf("%s: Unexpected exec error: %v", test.name, err)
continue
}
if !test.attachErr && err != nil {
t.Errorf("%s: Unexpected error: %v", test.name, err)
continue
}
if !test.attachErr && ex.req.URL().Path != test.attachPath {
t.Errorf("%s: Did not get expected path for exec request", test.name)
continue
}
}
}
func attachPod() *api.Pod {
return &api.Pod{
ObjectMeta: api.ObjectMeta{Name: "foo", Namespace: "test", ResourceVersion: "10"},
Spec: api.PodSpec{
RestartPolicy: api.RestartPolicyAlways,
DNSPolicy: api.DNSClusterFirst,
Containers: []api.Container{
{
Name: "bar",
},
},
},
Status: api.PodStatus{
Phase: api.PodRunning,
},
}
}

1
pkg/kubectl/cmd/cmd.go
View File

@@ -135,6 +135,7 @@ Find more information at https://github.com/GoogleCloudPlatform/kubernetes.`,
cmds.AddCommand(NewCmdRollingUpdate(f, out))
cmds.AddCommand(NewCmdScale(f, out))
cmds.AddCommand(NewCmdAttach(f, in, out, err))
cmds.AddCommand(NewCmdExec(f, in, out, err))
cmds.AddCommand(NewCmdPortForward(f))
cmds.AddCommand(NewCmdProxy(f, out))