package client import ( "fmt" "io" "golang.org/x/net/context" "github.com/Sirupsen/logrus" Cli "github.com/docker/docker/cli" flag "github.com/docker/docker/pkg/mflag" "github.com/docker/docker/pkg/promise" "github.com/docker/engine-api/types" ) // 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 := ParseExec(cmd, args) container := cmd.Arg(0) // just in case the ParseExec does not exit if container == "" || err != nil { return Cli.StatusError{StatusCode: 1} } if *detachKeys != "" { cli.configFile.DetachKeys = *detachKeys } // Send client escape keys execConfig.DetachKeys = cli.configFile.DetachKeys ctx := context.Background() response, err := cli.client.ContainerExecCreate(ctx, container, *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(ctx, 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(ctx, execID, *execConfig) if err != nil { return err } defer resp.Close() errCh = promise.Go(func() error { return cli.HoldHijackedConnection(ctx, execConfig.Tty, in, out, stderr, resp) }) if execConfig.Tty && cli.isTerminalIn { if err := cli.MonitorTtySize(ctx, 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 = cli.getExecExitCode(ctx, execID); err != nil { return err } if status != 0 { return Cli.StatusError{StatusCode: status} } return nil } // ParseExec parses the specified args for the specified command and generates // an ExecConfig from it. // If the minimal number of specified args is not right or if specified args are // not valid, it will return an error. func ParseExec(cmd *flag.FlagSet, args []string) (*types.ExecConfig, error) { var ( flStdin = cmd.Bool([]string{"i", "-interactive"}, false, "Keep STDIN open even if not attached") flTty = cmd.Bool([]string{"t", "-tty"}, false, "Allocate a pseudo-TTY") flDetach = cmd.Bool([]string{"d", "-detach"}, false, "Detached mode: run command in the background") flUser = cmd.String([]string{"u", "-user"}, "", "Username or UID (format: [:])") flPrivileged = cmd.Bool([]string{"-privileged"}, false, "Give extended privileges to the command") execCmd []string ) cmd.Require(flag.Min, 2) if err := cmd.ParseFlags(args, true); err != nil { return nil, err } parsedArgs := cmd.Args() execCmd = parsedArgs[1:] execConfig := &types.ExecConfig{ User: *flUser, Privileged: *flPrivileged, Tty: *flTty, Cmd: execCmd, Detach: *flDetach, } // If -d is not set, attach to everything by default if !*flDetach { execConfig.AttachStdout = true execConfig.AttachStderr = true if *flStdin { execConfig.AttachStdin = true } } return execConfig, nil }