// CmdExec runs a command in a running container.
//
// 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)
execConfig, err := runconfig.ParseExec(cmd, args)
// just in case the ParseExec does not exit
if execConfig.Container == "" || err != nil {
return Cli.StatusError{StatusCode: 1}
}
serverResp, err := cli.call("POST", "/containers/"+execConfig.Container+"/exec", execConfig, nil)
if err != nil {
return err
}
defer serverResp.body.Close()
var response types.ContainerExecCreateResponse
if err := json.NewDecoder(serverResp.body).Decode(&response); err != nil {
return err
}
execID := response.ID
if execID == "" {
fmt.Fprintf(cli.out, "exec ID empty")
return nil
}
//Temp struct for execStart so that we don't need to transfer all the execConfig
execStartCheck := &types.ExecStartCheck{
Detach: execConfig.Detach,
Tty: execConfig.Tty,
}
if !execConfig.Detach {
if err := cli.CheckTtyInput(execConfig.AttachStdin, execConfig.Tty); err != nil {
return err
}
} else {
if _, _, err := readBody(cli.call("POST", "/exec/"+execID+"/start", execStartCheck, nil)); err != nil {
return err
}
// For now don't print this - wait for when we support exec wait()
// fmt.Fprintf(cli.out, "%s\n", execID)
return nil
}
// Interactive exec requested.
var (
out, stderr io.Writer
in io.ReadCloser
hijacked = make(chan io.Closer)
errCh chan error
)
// Block the return until the chan gets closed
defer func() {
logrus.Debugf("End of CmdExec(), Waiting for hijack to finish.")
if _, ok := <-hijacked; ok {
fmt.Fprintln(cli.err, "Hijack did not finish (chan still open)")
}
}()
if execConfig.AttachStdin {
in = cli.in
}
if execConfig.AttachStdout {
out = cli.out
}
if execConfig.AttachStderr {
if execConfig.Tty {
stderr = cli.out
} else {
stderr = cli.err
}
}
errCh = promise.Go(func() error {
return cli.hijack("POST", "/exec/"+execID+"/start", execConfig.Tty, in, out, stderr, hijacked, execConfig)
})
// Acknowledge the hijack before starting
select {
case closer := <-hijacked:
// Make sure that hijack gets closed when returning. (result
// in closing hijack chan and freeing server's goroutines.
if closer != nil {
defer closer.Close()
}
case err := <-errCh:
if err != nil {
logrus.Debugf("Error hijack: %s", err)
return err
}
}
if execConfig.Tty && cli.isTerminalIn {
if err := cli.monitorTtySize(execID, true); err != nil {
fmt.Fprintf(cli.err, "Error monitoring TTY size: %s\n", err)
}
}
if err := <-errCh; err != nil {
logrus.Debugf("Error hijack: %s", err)
return err
}
var status int
if _, status, err = getExecExitCode(cli, execID); err != nil {
return err
}
if status != 0 {
return Cli.StatusError{StatusCode: status}
}
return nil
}
// CmdExec runs a command in a running container.
//
// 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
if execConfig.Container == "" || err != nil {
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
}
execID := response.ID
if execID == "" {
fmt.Fprintf(cli.out, "exec ID empty")
return nil
}
//Temp struct for execStart so that we don't need to transfer all the execConfig
if !execConfig.Detach {
if err := cli.CheckTtyInput(execConfig.AttachStdin, execConfig.Tty); err != nil {
return err
}
} else {
execStartCheck := types.ExecStartCheck{
Detach: execConfig.Detach,
Tty: execConfig.Tty,
}
if err := cli.client.ContainerExecStart(execID, execStartCheck); err != nil {
return err
}
// For now don't print this - wait for when we support exec wait()
// fmt.Fprintf(cli.out, "%s\n", execID)
return nil
}
// Interactive exec requested.
var (
out, stderr io.Writer
in io.ReadCloser
errCh chan error
)
if execConfig.AttachStdin {
in = cli.in
}
if execConfig.AttachStdout {
out = cli.out
}
if execConfig.AttachStderr {
if execConfig.Tty {
stderr = cli.out
} else {
stderr = cli.err
}
}
resp, err := cli.client.ContainerExecAttach(execID, *execConfig)
if err != nil {
return err
}
defer resp.Close()
errCh = promise.Go(func() error {
return cli.holdHijackedConnection(execConfig.Tty, in, out, stderr, resp)
})
if execConfig.Tty && cli.isTerminalIn {
if err := cli.monitorTtySize(execID, true); err != nil {
fmt.Fprintf(cli.err, "Error monitoring TTY size: %s\n", err)
}
}
if err := <-errCh; err != nil {
logrus.Debugf("Error hijack: %s", err)
return err
}
var status int
if _, status, err = getExecExitCode(cli, execID); err != nil {
return err
}
if status != 0 {
return Cli.StatusError{StatusCode: status}
}
return nil
}