package client import ( "errors" "io" "golang.org/x/net/context" Cli "github.com/docker/docker/cli" flag "github.com/docker/docker/pkg/mflag" ) // CmdSave saves one or more images to a tar archive. // // The tar archive is written to STDOUT by default, or written to a file. // // Usage: docker save [OPTIONS] IMAGE [IMAGE...] func (cli *DockerCli) CmdSave(args ...string) error { cmd := Cli.Subcmd("save", []string{"IMAGE [IMAGE...]"}, Cli.DockerCommands["save"].Description+" (streamed to STDOUT by default)", true) outfile := cmd.String([]string{"o", "-output"}, "", "Write to a file, instead of STDOUT") cmd.Require(flag.Min, 1) cmd.ParseFlags(args, true) if *outfile == "" && cli.isTerminalOut { return errors.New("Cowardly refusing to save to a terminal. Use the -o flag or redirect.") } responseBody, err := cli.client.ImageSave(context.Background(), cmd.Args()) if err != nil { return err } defer responseBody.Close() if *outfile == "" { _, err := io.Copy(cli.out, responseBody) return err } return CopyToFile(*outfile, responseBody) }