package container import ( "fmt" "io" "net/http/httputil" "os" "runtime" "strings" "syscall" "github.com/Sirupsen/logrus" "github.com/docker/docker/api/types" "github.com/docker/docker/api/types/container" "github.com/docker/docker/cli" "github.com/docker/docker/cli/command" "github.com/docker/docker/pkg/promise" "github.com/docker/docker/pkg/signal" "github.com/docker/libnetwork/resolvconf/dns" "github.com/pkg/errors" "github.com/spf13/cobra" "github.com/spf13/pflag" "golang.org/x/net/context" ) type runOptions struct { detach bool sigProxy bool name string detachKeys string } // NewRunCommand create a new `docker run` command func NewRunCommand(dockerCli *command.DockerCli) *cobra.Command { var opts runOptions var copts *containerOptions cmd := &cobra.Command{ Use: "run [OPTIONS] IMAGE [COMMAND] [ARG...]", Short: "Run a command in a new container", Args: cli.RequiresMinArgs(1), RunE: func(cmd *cobra.Command, args []string) error { copts.Image = args[0] if len(args) > 1 { copts.Args = args[1:] } return runRun(dockerCli, cmd.Flags(), &opts, copts) }, } flags := cmd.Flags() flags.SetInterspersed(false) // These are flags not stored in Config/HostConfig flags.BoolVarP(&opts.detach, "detach", "d", false, "Run container in background and print container ID") flags.BoolVar(&opts.sigProxy, "sig-proxy", true, "Proxy received signals to the process") flags.StringVar(&opts.name, "name", "", "Assign a name to the container") flags.StringVar(&opts.detachKeys, "detach-keys", "", "Override the key sequence for detaching a container") // Add an explicit help that doesn't have a `-h` to prevent the conflict // with hostname flags.Bool("help", false, "Print usage") command.AddTrustVerificationFlags(flags) copts = addFlags(flags) return cmd } func warnOnOomKillDisable(hostConfig container.HostConfig, stderr io.Writer) { if hostConfig.OomKillDisable != nil && *hostConfig.OomKillDisable && hostConfig.Memory == 0 { fmt.Fprintln(stderr, "WARNING: Disabling the OOM killer on containers without setting a '-m/--memory' limit may be dangerous.") } } // check the DNS settings passed via --dns against localhost regexp to warn if // they are trying to set a DNS to a localhost address func warnOnLocalhostDNS(hostConfig container.HostConfig, stderr io.Writer) { for _, dnsIP := range hostConfig.DNS { if dns.IsLocalhost(dnsIP) { fmt.Fprintf(stderr, "WARNING: Localhost DNS setting (--dns=%s) may fail in containers.\n", dnsIP) return } } } func runRun(dockerCli *command.DockerCli, flags *pflag.FlagSet, opts *runOptions, copts *containerOptions) error { containerConfig, err := parse(flags, copts) // just in case the parse does not exit if err != nil { reportError(dockerCli.Err(), "run", err.Error(), true) return cli.StatusError{StatusCode: 125} } return runContainer(dockerCli, opts, copts, containerConfig) } func runContainer(dockerCli *command.DockerCli, opts *runOptions, copts *containerOptions, containerConfig *containerConfig) error { config := containerConfig.Config hostConfig := containerConfig.HostConfig stdout, stderr := dockerCli.Out(), dockerCli.Err() client := dockerCli.Client() // TODO: pass this as an argument cmdPath := "run" warnOnOomKillDisable(*hostConfig, stderr) warnOnLocalhostDNS(*hostConfig, stderr) config.ArgsEscaped = false if !opts.detach { if err := dockerCli.In().CheckTty(config.AttachStdin, config.Tty); err != nil { return err } } else { if copts.attach.Len() != 0 { return errors.New("Conflicting options: -a and -d") } config.AttachStdin = false config.AttachStdout = false config.AttachStderr = false config.StdinOnce = false } // Disable sigProxy when in TTY mode if config.Tty { opts.sigProxy = false } // Telling the Windows daemon the initial size of the tty during start makes // a far better user experience rather than relying on subsequent resizes // to cause things to catch up. if runtime.GOOS == "windows" { hostConfig.ConsoleSize[0], hostConfig.ConsoleSize[1] = dockerCli.Out().GetTtySize() } ctx, cancelFun := context.WithCancel(context.Background()) createResponse, err := createContainer(ctx, dockerCli, containerConfig, opts.name) if err != nil { reportError(stderr, cmdPath, err.Error(), true) return runStartContainerErr(err) } if opts.sigProxy { sigc := ForwardAllSignals(ctx, dockerCli, createResponse.ID) defer signal.StopCatch(sigc) } var ( waitDisplayID chan struct{} errCh chan error ) if !config.AttachStdout && !config.AttachStderr { // Make this asynchronous to allow the client to write to stdin before having to read the ID waitDisplayID = make(chan struct{}) go func() { defer close(waitDisplayID) fmt.Fprintln(stdout, createResponse.ID) }() } attach := config.AttachStdin || config.AttachStdout || config.AttachStderr if attach { if opts.detachKeys != "" { dockerCli.ConfigFile().DetachKeys = opts.detachKeys } close, err := attachContainer(ctx, dockerCli, &errCh, config, createResponse.ID) defer close() if err != nil { return err } } statusChan := waitExitOrRemoved(ctx, dockerCli, createResponse.ID, copts.autoRemove) //start the container if err := client.ContainerStart(ctx, createResponse.ID, types.ContainerStartOptions{}); err != nil { // If we have holdHijackedConnection, we should notify // holdHijackedConnection we are going to exit and wait // to avoid the terminal are not restored. if attach { cancelFun() <-errCh } reportError(stderr, cmdPath, err.Error(), false) if copts.autoRemove { // wait container to be removed <-statusChan } return runStartContainerErr(err) } if (config.AttachStdin || config.AttachStdout || config.AttachStderr) && config.Tty && dockerCli.Out().IsTerminal() { if err := MonitorTtySize(ctx, dockerCli, createResponse.ID, false); err != nil { fmt.Fprintln(stderr, "Error monitoring TTY size:", err) } } if errCh != nil { if err := <-errCh; err != nil { logrus.Debugf("Error hijack: %s", err) return err } } // Detached mode: wait for the id to be displayed and return. if !config.AttachStdout && !config.AttachStderr { // Detached mode <-waitDisplayID return nil } status := <-statusChan if status != 0 { return cli.StatusError{StatusCode: status} } return nil } func attachContainer( ctx context.Context, dockerCli *command.DockerCli, errCh *chan error, config *container.Config, containerID string, ) (func(), error) { stdout, stderr := dockerCli.Out(), dockerCli.Err() var ( out, cerr io.Writer in io.ReadCloser ) if config.AttachStdin { in = dockerCli.In() } if config.AttachStdout { out = stdout } if config.AttachStderr { if config.Tty { cerr = stdout } else { cerr = stderr } } options := types.ContainerAttachOptions{ Stream: true, Stdin: config.AttachStdin, Stdout: config.AttachStdout, Stderr: config.AttachStderr, DetachKeys: dockerCli.ConfigFile().DetachKeys, } resp, errAttach := dockerCli.Client().ContainerAttach(ctx, containerID, options) if errAttach != nil && errAttach != httputil.ErrPersistEOF { // ContainerAttach returns an ErrPersistEOF (connection closed) // means server met an error and put it in Hijacked connection // keep the error and read detailed error message from hijacked connection later return nil, errAttach } *errCh = promise.Go(func() error { if errHijack := holdHijackedConnection(ctx, dockerCli, config.Tty, in, out, cerr, resp); errHijack != nil { return errHijack } return errAttach }) return resp.Close, nil } // reportError is a utility method that prints a user-friendly message // containing the error that occurred during parsing and a suggestion to get help func reportError(stderr io.Writer, name string, str string, withHelp bool) { str = strings.TrimSuffix(str, ".") + "." if withHelp { str += "\nSee '" + os.Args[0] + " " + name + " --help'." } fmt.Fprintf(stderr, "%s: %s\n", os.Args[0], str) } // if container start fails with 'not found'/'no such' error, return 127 // if container start fails with 'permission denied' error, return 126 // return 125 for generic docker daemon failures func runStartContainerErr(err error) error { trimmedErr := strings.TrimPrefix(err.Error(), "Error response from daemon: ") statusError := cli.StatusError{StatusCode: 125} if strings.Contains(trimmedErr, "executable file not found") || strings.Contains(trimmedErr, "no such file or directory") || strings.Contains(trimmedErr, "system cannot find the file specified") { statusError = cli.StatusError{StatusCode: 127} } else if strings.Contains(trimmedErr, syscall.EACCES.Error()) { statusError = cli.StatusError{StatusCode: 126} } return statusError }