package service import ( "fmt" "strconv" "strings" "golang.org/x/net/context" "github.com/docker/docker/api/types" "github.com/docker/docker/cli" "github.com/docker/docker/cli/command" "github.com/spf13/cobra" ) func newScaleCommand(dockerCli *command.DockerCli) *cobra.Command { return &cobra.Command{ Use: "scale SERVICE=REPLICAS [SERVICE=REPLICAS...]", Short: "Scale one or multiple services", Args: scaleArgs, RunE: func(cmd *cobra.Command, args []string) error { return runScale(dockerCli, args) }, } } func scaleArgs(cmd *cobra.Command, args []string) error { if err := cli.RequiresMinArgs(1)(cmd, args); err != nil { return err } for _, arg := range args { if parts := strings.SplitN(arg, "=", 2); len(parts) != 2 { return fmt.Errorf( "Invalid scale specifier '%s'.\nSee '%s --help'.\n\nUsage: %s\n\n%s", arg, cmd.CommandPath(), cmd.UseLine(), cmd.Short, ) } } return nil } func runScale(dockerCli *command.DockerCli, args []string) error { var errors []string for _, arg := range args { parts := strings.SplitN(arg, "=", 2) serviceID, scale := parts[0], parts[1] if err := runServiceScale(dockerCli, serviceID, scale); err != nil { errors = append(errors, fmt.Sprintf("%s: %s", serviceID, err.Error())) } } if len(errors) == 0 { return nil } return fmt.Errorf(strings.Join(errors, "\n")) } func runServiceScale(dockerCli *command.DockerCli, serviceID string, scale string) error { client := dockerCli.Client() ctx := context.Background() service, _, err := client.ServiceInspectWithRaw(ctx, serviceID) if err != nil { return err } serviceMode := &service.Spec.Mode if serviceMode.Replicated == nil { return fmt.Errorf("scale can only be used with replicated mode") } uintScale, err := strconv.ParseUint(scale, 10, 64) if err != nil { return fmt.Errorf("invalid replicas value %s: %s", scale, err.Error()) } serviceMode.Replicated.Replicas = &uintScale err = client.ServiceUpdate(ctx, service.ID, service.Version, service.Spec, types.ServiceUpdateOptions{}) if err != nil { return err } fmt.Fprintf(dockerCli.Out(), "%s scaled to %s\n", serviceID, scale) return nil }