github.com/walkingsparrow/docker@v1.4.2-0.20151218153551-b708a2249bfa/api/client/start.go (about)

     1  package client
     2  
     3  import (
     4  	"fmt"
     5  	"io"
     6  	"os"
     7  	"strings"
     8  
     9  	"github.com/Sirupsen/logrus"
    10  	"github.com/docker/docker/api/types"
    11  	Cli "github.com/docker/docker/cli"
    12  	flag "github.com/docker/docker/pkg/mflag"
    13  	"github.com/docker/docker/pkg/promise"
    14  	"github.com/docker/docker/pkg/signal"
    15  )
    16  
    17  func (cli *DockerCli) forwardAllSignals(cid string) chan os.Signal {
    18  	sigc := make(chan os.Signal, 128)
    19  	signal.CatchAll(sigc)
    20  	go func() {
    21  		for s := range sigc {
    22  			if s == signal.SIGCHLD {
    23  				continue
    24  			}
    25  			var sig string
    26  			for sigStr, sigN := range signal.SignalMap {
    27  				if sigN == s {
    28  					sig = sigStr
    29  					break
    30  				}
    31  			}
    32  			if sig == "" {
    33  				fmt.Fprintf(cli.err, "Unsupported signal: %v. Discarding.\n", s)
    34  				continue
    35  			}
    36  
    37  			if err := cli.client.ContainerKill(cid, sig); err != nil {
    38  				logrus.Debugf("Error sending signal: %s", err)
    39  			}
    40  		}
    41  	}()
    42  	return sigc
    43  }
    44  
    45  // CmdStart starts one or more containers.
    46  //
    47  // Usage: docker start [OPTIONS] CONTAINER [CONTAINER...]
    48  func (cli *DockerCli) CmdStart(args ...string) error {
    49  	cmd := Cli.Subcmd("start", []string{"CONTAINER [CONTAINER...]"}, Cli.DockerCommands["start"].Description, true)
    50  	attach := cmd.Bool([]string{"a", "-attach"}, false, "Attach STDOUT/STDERR and forward signals")
    51  	openStdin := cmd.Bool([]string{"i", "-interactive"}, false, "Attach container's STDIN")
    52  	cmd.Require(flag.Min, 1)
    53  
    54  	cmd.ParseFlags(args, true)
    55  
    56  	if *attach || *openStdin {
    57  		// We're going to attach to a container.
    58  		// 1. Ensure we only have one container.
    59  		if cmd.NArg() > 1 {
    60  			return fmt.Errorf("You cannot start and attach multiple containers at once.")
    61  		}
    62  
    63  		// 2. Attach to the container.
    64  		containerID := cmd.Arg(0)
    65  		c, err := cli.client.ContainerInspect(containerID)
    66  		if err != nil {
    67  			return err
    68  		}
    69  
    70  		if !c.Config.Tty {
    71  			sigc := cli.forwardAllSignals(containerID)
    72  			defer signal.StopCatch(sigc)
    73  		}
    74  
    75  		options := types.ContainerAttachOptions{
    76  			ContainerID: containerID,
    77  			Stream:      true,
    78  			Stdin:       *openStdin && c.Config.OpenStdin,
    79  			Stdout:      true,
    80  			Stderr:      true,
    81  		}
    82  
    83  		var in io.ReadCloser
    84  		if options.Stdin {
    85  			in = cli.in
    86  		}
    87  
    88  		resp, err := cli.client.ContainerAttach(options)
    89  		if err != nil {
    90  			return err
    91  		}
    92  		defer resp.Close()
    93  
    94  		cErr := promise.Go(func() error {
    95  			return cli.holdHijackedConnection(c.Config.Tty, in, cli.out, cli.err, resp)
    96  		})
    97  
    98  		// 3. Start the container.
    99  		if err := cli.client.ContainerStart(containerID); err != nil {
   100  			return err
   101  		}
   102  
   103  		// 4. Wait for attachment to break.
   104  		if c.Config.Tty && cli.isTerminalOut {
   105  			if err := cli.monitorTtySize(containerID, false); err != nil {
   106  				fmt.Fprintf(cli.err, "Error monitoring TTY size: %s\n", err)
   107  			}
   108  		}
   109  		if attchErr := <-cErr; attchErr != nil {
   110  			return attchErr
   111  		}
   112  		_, status, err := getExitCode(cli, containerID)
   113  		if err != nil {
   114  			return err
   115  		}
   116  		if status != 0 {
   117  			return Cli.StatusError{StatusCode: status}
   118  		}
   119  	} else {
   120  		// We're not going to attach to anything.
   121  		// Start as many containers as we want.
   122  		return cli.startContainersWithoutAttachments(cmd.Args())
   123  	}
   124  
   125  	return nil
   126  }
   127  
   128  func (cli *DockerCli) startContainersWithoutAttachments(containerIDs []string) error {
   129  	var failedContainers []string
   130  	for _, containerID := range containerIDs {
   131  		if err := cli.client.ContainerStart(containerID); err != nil {
   132  			fmt.Fprintf(cli.err, "%s\n", err)
   133  			failedContainers = append(failedContainers, containerID)
   134  		} else {
   135  			fmt.Fprintf(cli.out, "%s\n", containerID)
   136  		}
   137  	}
   138  
   139  	if len(failedContainers) > 0 {
   140  		return fmt.Errorf("Error: failed to start containers: %v", strings.Join(failedContainers, ", "))
   141  	}
   142  	return nil
   143  }