Implement configurable detach key

Implement configurable detach keys (for `attach`, exec`, `run` and
`start`) using the client-side configuration

- Adds a `--detach-keys` flag to `attach`, `exec`, `run` and `start`
  commands.
- Adds a new configuration field (in `~/.docker/config.json`) to
  configure the default escape keys for docker client.

Signed-off-by: Vincent Demeester <vincent@sbr.pm>
Upstream-commit: 15aa2a663b47b6126a66efefcadb64edfbffb9f5
Component: engine

components/engine/api/client/attach.go

@@ -18,6 +18,7 @@ func (cli *DockerCli) CmdAttach(args ...string) error {
 	cmd := Cli.Subcmd("attach", []string{"CONTAINER"}, Cli.DockerCommands["attach"].Description, true)
 	noStdin := cmd.Bool([]string{"-no-stdin"}, false, "Do not attach STDIN")
 	proxy := cmd.Bool([]string{"-sig-proxy"}, true, "Proxy all received signals to the process")
+	detachKeys := cmd.String([]string{"-detach-keys"}, "", "Override the key sequence for detaching a container")
 
 	cmd.Require(flag.Exact, 1)
 
@@ -46,12 +47,17 @@ func (cli *DockerCli) CmdAttach(args ...string) error {
 		}
 	}
 
+	if *detachKeys != "" {
+		cli.configFile.DetachKeys = *detachKeys
+	}
+
 	options := types.ContainerAttachOptions{
 		ContainerID: cmd.Arg(0),
 		Stream:      true,
 		Stdin:       !*noStdin && c.Config.OpenStdin,
 		Stdout:      true,
 		Stderr:      true,
+		DetachKeys:  cli.configFile.DetachKeys,
 	}
 
 	var in io.ReadCloser

components/engine/api/client/exec.go

@@ -16,6 +16,7 @@ import (
 // Usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG...]
 func (cli *DockerCli) CmdExec(args ...string) error {
 	cmd := Cli.Subcmd("exec", []string{"CONTAINER COMMAND [ARG...]"}, Cli.DockerCommands["exec"].Description, true)
+	detachKeys := cmd.String([]string{"-detach-keys"}, "", "Override the key sequence for detaching a container")
 
 	execConfig, err := runconfig.ParseExec(cmd, args)
 	// just in case the ParseExec does not exit
@@ -23,6 +24,13 @@ func (cli *DockerCli) CmdExec(args ...string) error {
 		return Cli.StatusError{StatusCode: 1}
 	}
 
+	if *detachKeys != "" {
+		cli.configFile.DetachKeys = *detachKeys
+	}
+
+	// Send client escape keys
+	execConfig.DetachKeys = cli.configFile.DetachKeys
+
 	response, err := cli.client.ContainerExecCreate(*execConfig)
 	if err != nil {
 		return err

components/engine/api/client/lib/container_attach.go

@@ -24,6 +24,9 @@ func (cli *Client) ContainerAttach(options types.ContainerAttachOptions) (types.
 	if options.Stderr {
 		query.Set("stderr", "1")
 	}
+	if options.DetachKeys != "" {
+		query.Set("detachKeys", options.DetachKeys)
+	}
 
 	headers := map[string][]string{"Content-Type": {"text/plain"}}
 	return cli.postHijacked("/containers/"+options.ContainerID+"/attach", query, nil, headers)

components/engine/api/client/run.go

@@ -74,6 +74,7 @@ func (cli *DockerCli) CmdRun(args ...string) error {
 		flDetach     = cmd.Bool([]string{"d", "-detach"}, false, "Run container in background and print container ID")
 		flSigProxy   = cmd.Bool([]string{"-sig-proxy"}, true, "Proxy received signals to the process")
 		flName       = cmd.String([]string{"-name"}, "", "Assign a name to the container")
+		flDetachKeys = cmd.String([]string{"-detach-keys"}, "", "Override the key sequence for detaching a container")
 		flAttach     *opts.ListOpts
 
 		ErrConflictAttachDetach               = fmt.Errorf("Conflicting options: -a and -d")
@@ -188,12 +189,17 @@ func (cli *DockerCli) CmdRun(args ...string) error {
 			}
 		}
 
+		if *flDetachKeys != "" {
+			cli.configFile.DetachKeys = *flDetachKeys
+		}
+
 		options := types.ContainerAttachOptions{
 			ContainerID: createResponse.ID,
 			Stream:      true,
 			Stdin:       config.AttachStdin,
 			Stdout:      config.AttachStdout,
 			Stderr:      config.AttachStderr,
+			DetachKeys:  cli.configFile.DetachKeys,
 		}
 
 		resp, err := cli.client.ContainerAttach(options)

components/engine/api/client/start.go

@@ -49,6 +49,7 @@ func (cli *DockerCli) CmdStart(args ...string) error {
 	cmd := Cli.Subcmd("start", []string{"CONTAINER [CONTAINER...]"}, Cli.DockerCommands["start"].Description, true)
 	attach := cmd.Bool([]string{"a", "-attach"}, false, "Attach STDOUT/STDERR and forward signals")
 	openStdin := cmd.Bool([]string{"i", "-interactive"}, false, "Attach container's STDIN")
+	detachKeys := cmd.String([]string{"-detach-keys"}, "", "Override the key sequence for detaching a container")
 	cmd.Require(flag.Min, 1)
 
 	cmd.ParseFlags(args, true)
@@ -72,12 +73,17 @@ func (cli *DockerCli) CmdStart(args ...string) error {
 			defer signal.StopCatch(sigc)
 		}
 
+		if *detachKeys != "" {
+			cli.configFile.DetachKeys = *detachKeys
+		}
+
 		options := types.ContainerAttachOptions{
 			ContainerID: containerID,
 			Stream:      true,
 			Stdin:       *openStdin && c.Config.OpenStdin,
 			Stdout:      true,
 			Stderr:      true,
+			DetachKeys:  cli.configFile.DetachKeys,
 		}
 
 		var in io.ReadCloser