'docker run -i' optionally opens stdin. 'docker attach' attaches to a running container (including stdin). 'docker run -t' allocates a tty (still buggy)

container.go

@@ -13,6 +13,7 @@ import (
 	"strings"
 	"syscall"
 	"time"
+	"github.com/kr/pty"
 )
 
 type Container struct {
@@ -32,6 +33,8 @@ type Container struct {
 	cmd           *exec.Cmd
 	stdout        *writeBroadcaster
 	stderr        *writeBroadcaster
+	stdin         io.ReadCloser
+	stdinPipe     io.WriteCloser
 
 	stdoutLog *bytes.Buffer
 	stderrLog *bytes.Buffer
@@ -40,6 +43,8 @@ type Container struct {
 type Config struct {
 	Hostname string
 	Ram      int64
+	Tty	 bool		// Attach standard streams to a tty, including stdin if it is not closed.
+	OpenStdin	bool	// Open stdin
 }
 
 func createContainer(id string, root string, command string, args []string, layers []string, config *Config) (*Container, error) {
@@ -59,6 +64,11 @@ func createContainer(id string, root string, command string, args []string, laye
 		stdoutLog:     new(bytes.Buffer),
 		stderrLog:     new(bytes.Buffer),
 	}
+	if container.Config.OpenStdin {
+		container.stdin, container.stdinPipe = io.Pipe()
+	} else {
+		container.stdinPipe = NopWriteCloser(ioutil.Discard)	// Silently drop stdin
+	}
 	container.stdout.AddWriter(NopWriteCloser(container.stdoutLog))
 	container.stderr.AddWriter(NopWriteCloser(container.stderrLog))
 
@@ -94,6 +104,11 @@ func loadContainer(containerPath string) (*Container, error) {
 	if err := container.Filesystem.createMountPoints(); err != nil {
 		return nil, err
 	}
+	if container.Config.OpenStdin {
+		container.stdin, container.stdinPipe = io.Pipe()
+	} else {
+		container.stdinPipe = NopWriteCloser(ioutil.Discard)	// Silently drop stdin
+	}
 	container.State = newState()
 	return container, nil
 }
@@ -180,9 +195,67 @@ func (container *Container) Start() error {
 	params = append(params, container.Args...)
 
 	container.cmd = exec.Command("/usr/bin/lxc-start", params...)
+
+	if container.Config.Tty {
+		Pty, tty, err := pty.Open()
+		if err != nil {
+			return err
+		}
+		container.cmd.Stdout = tty
+		container.cmd.Stderr = tty
+		if container.stdin != nil {
+			container.cmd.Stdin = tty
+		}
+		container.cmd.SysProcAttr = &syscall.SysProcAttr{Setctty: true, Setsid: true}
+		if err := container.cmd.Start(); err != nil {
+			Pty.Close()
+			return err
+		}
+		tty.Close()
+		// Attach Pty to stdout
+		go func() {
+			defer container.stdout.Close()
+			for {
+				data := make([]byte, 1024)
+				n, err := Pty.Read(data)
+				if err != nil {
+					return
+				}
+				log.Printf("STDOUT <%s>\n", data)
+				if _, err = container.stdout.Write(data[:n]); err != nil {
+					return
+				}
+				log.Printf("STDOUT SENT\n")
+			}
+			//io.Copy(container.stdout, Pty)
+			//container.stdout.Close()
+		}()
+		// Attach Pty to stderr
+		go func() {
+			io.Copy(container.stderr, Pty)
+			container.stderr.Close()
+		}()
+		// Attach Pty to stdin
+		if container.stdin != nil {
+			go func() {
+				defer Pty.Close()
+				io.Copy(Pty, container.stdin)
+			}()
+		}
+	} else {
 		container.cmd.Stdout = container.stdout
 		container.cmd.Stderr = container.stderr
-
+		if container.stdin != nil {
+			stdin, err := container.cmd.StdinPipe()
+			if err != nil {
+				return err
+			}
+			go func() {
+				defer stdin.Close()
+				io.Copy(stdin, container.stdin)
+			}()
+		}
+	}
 	if err := container.cmd.Start(); err != nil {
 		return err
 	}
@@ -214,6 +287,13 @@ func (container *Container) Output() (output []byte, err error) {
 	return output, err
 }
 
+// StdinPipe() returns a pipe connected to the standard input of the container's
+// active process.
+//
+func (container *Container) StdinPipe() (io.WriteCloser, error) {
+	return container.stdinPipe, nil
+}
+
 func (container *Container) StdoutPipe() (io.ReadCloser, error) {
 	reader, writer := io.Pipe()
 	container.stdout.AddWriter(writer)

dockerd/dockerd.go

@@ -18,6 +18,7 @@ import (
 	"net/http"
 	"encoding/json"
 	"bytes"
+	"sync"
 )
 
 
@@ -42,6 +43,7 @@ func (srv *Server) Help() string {
 		{"info", "Display system-wide information"},
 		{"tar", "Stream the contents of a container as a tar archive"},
 		{"web", "Generate a web UI"},
+		{"attach", "Attach to a running container"},
 	} {
 		help += fmt.Sprintf("    %-10.10s%s\n", cmd...)
 	}
@@ -507,9 +509,10 @@ func (srv *Server) CmdLogs(stdin io.ReadCloser, stdout io.Writer, args ...string
 }
 
 
-func (srv *Server) CreateContainer(img *image.Image, cmd string, args ...string) (*docker.Container, error) {
+func (srv *Server) CreateContainer(img *image.Image, tty bool, openStdin bool, cmd string, args ...string) (*docker.Container, error) {
 	id := future.RandomId()
-	container, err := srv.containers.Create(id, cmd, args, img.Layers, &docker.Config{Hostname: id})
+	container, err := srv.containers.Create(id, cmd, args, img.Layers,
+		&docker.Config{Hostname: id, Tty: tty, OpenStdin: openStdin})
 	if err != nil {
 		return nil, err
 	}
@@ -520,10 +523,57 @@ func (srv *Server) CreateContainer(img *image.Image, cmd string, args ...string)
 	return container, nil
 }
 
+func (srv *Server) CmdAttach(stdin io.ReadCloser, stdout io.Writer, args ...string) error {
+	cmd := rcli.Subcmd(stdout, "attach", "[OPTIONS]", "Attach to a running container")
+	fl_i := cmd.Bool("i", false, "Attach to stdin")
+	fl_o := cmd.Bool("o", true, "Attach to stdout")
+	fl_e := cmd.Bool("e", true, "Attach to stderr")
+	if err := cmd.Parse(args); err != nil {
+		return nil
+	}
+	if cmd.NArg() != 1 {
+		cmd.Usage()
+		return nil
+	}
+	name := cmd.Arg(0)
+	container := srv.containers.Get(name)
+	if container == nil {
+		return errors.New("No such container: " + name)
+	}
+	var wg sync.WaitGroup
+	if *fl_i {
+		c_stdin, err := container.StdinPipe()
+		if err != nil {
+			return err
+		}
+		wg.Add(1)
+		go func() { io.Copy(c_stdin, stdin); wg.Add(-1); }()
+	}
+	if *fl_o {
+		c_stdout, err := container.StdoutPipe()
+		if err != nil {
+			return err
+		}
+		wg.Add(1)
+		go func() { io.Copy(stdout, c_stdout); wg.Add(-1); }()
+	}
+	if *fl_e {
+		c_stderr, err := container.StderrPipe()
+		if err != nil {
+			return err
+		}
+		wg.Add(1)
+		go func() { io.Copy(stdout, c_stderr); wg.Add(-1); }()
+	}
+	wg.Wait()
+	return nil
+}
+
 func (srv *Server) CmdRun(stdin io.ReadCloser, stdout io.Writer, args ...string) error {
 	flags := rcli.Subcmd(stdout, "run", "[OPTIONS] IMAGE COMMAND [ARG...]", "Run a command in a new container")
 	fl_attach := flags.Bool("a", false, "Attach stdin and stdout")
-	//fl_tty := flags.Bool("t", false, "Allocate a pseudo-tty")
+	fl_stdin := flags.Bool("i", false, "Keep stdin open even if not attached")
+	fl_tty := flags.Bool("t", false, "Allocate a pseudo-tty")
 	if err := flags.Parse(args); err != nil {
 		return nil
 	}
@@ -538,31 +588,55 @@ func (srv *Server) CmdRun(stdin io.ReadCloser, stdout io.Writer, args ...string)
 		return errors.New("No such image: " + name)
 	}
 	// Create new container
-	container, err := srv.CreateContainer(img, cmd[0], cmd[1:]...)
+	container, err := srv.CreateContainer(img, *fl_tty, *fl_stdin, cmd[0], cmd[1:]...)
 	if err != nil {
 		return errors.New("Error creating container: " + err.Error())
 	}
-	// Run the container
+	if *fl_stdin {
-	if *fl_attach {
+		cmd_stdin, err := container.StdinPipe()
-		cmd_stdout, err := container.StdoutPipe()
 		if err != nil {
 			return err
 		}
+		if *fl_attach {
+			future.Go(func() error {
+				log.Printf("CmdRun(): start receiving stdin\n")
+				_, err := io.Copy(cmd_stdin, stdin);
+				log.Printf("CmdRun(): done receiving stdin\n")
+				cmd_stdin.Close()
+				return err
+			})
+		}
+	}
+	// Run the container
+	if *fl_attach {
 		cmd_stderr, err := container.StderrPipe()
 		if err != nil {
 			return err
 		}
+		cmd_stdout, err := container.StdoutPipe()
+		if err != nil {
+			return err
+		}
 		if err := container.Start(); err != nil {
 			return err
 		}
-		sending_stdout := future.Go(func() error { _, err := io.Copy(stdout, cmd_stdout); return err })
+		sending_stdout := future.Go(func() error {
-		sending_stderr := future.Go(func() error { _, err := io.Copy(stdout, cmd_stderr); return err })
+			_, err := io.Copy(stdout, cmd_stdout);
+			return err
+		})
+		sending_stderr := future.Go(func() error {
+			_, err := io.Copy(stdout, cmd_stderr);
+			return err
+		})
 		err_sending_stdout := <-sending_stdout
 		err_sending_stderr := <-sending_stderr
 		if err_sending_stdout != nil {
 			return err_sending_stdout
 		}
+		if err_sending_stderr != nil {
 			return err_sending_stderr
+		}
+		container.Wait()
 	} else {
 		if err := container.Start(); err != nil {
 			return err