package container import ( "errors" "io" "github.com/docker/docker/cli" "github.com/docker/docker/cli/command" "github.com/spf13/cobra" "golang.org/x/net/context" ) type exportOptions struct { container string output string } // NewExportCommand creates a new `docker export` command func NewExportCommand(dockerCli *command.DockerCli) *cobra.Command { var opts exportOptions cmd := &cobra.Command{ Use: "export [OPTIONS] CONTAINER", Short: "Export a container's filesystem as a tar archive", Args: cli.ExactArgs(1), RunE: func(cmd *cobra.Command, args []string) error { opts.container = args[0] return runExport(dockerCli, opts) }, } flags := cmd.Flags() flags.StringVarP(&opts.output, "output", "o", "", "Write to a file, instead of STDOUT") return cmd } func runExport(dockerCli *command.DockerCli, opts exportOptions) error { if opts.output == "" && dockerCli.Out().IsTerminal() { return errors.New("Cowardly refusing to save to a terminal. Use the -o flag or redirect.") } clnt := dockerCli.Client() responseBody, err := clnt.ContainerExport(context.Background(), opts.container) if err != nil { return err } defer responseBody.Close() if opts.output == "" { _, err := io.Copy(dockerCli.Out(), responseBody) return err } return command.CopyToFile(opts.output, responseBody) }