Convert docker root command to use pflag and cobra

Fix the daemon proxy for cobra commands.

Signed-off-by: Daniel Nephin <dnephin@docker.com>

daemon.go

@@ -1,18 +0,0 @@
-package main
-
-const daemonBinary = "dockerd"
-
-// DaemonProxy acts as a cli.Handler to proxy calls to the daemon binary
-type DaemonProxy struct{}
-
-// NewDaemonProxy returns a new handler
-func NewDaemonProxy() DaemonProxy {
-	return DaemonProxy{}
-}
-
-// Command returns a cli command handler if one exists
-func (p DaemonProxy) Command(name string) func(...string) error {
-	return map[string]func(...string) error{
-		"daemon": p.CmdDaemon,
-	}[name]
-}

daemon_none.go

@@ -4,12 +4,22 @@ package main
 
 import (
 	"fmt"
+	"github.com/spf13/cobra"
 	"runtime"
 	"strings"
 )
 
-// CmdDaemon reports on an error on windows, because there is no exec
-func (p DaemonProxy) CmdDaemon(args ...string) error {
+func newDaemonCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:    "daemon",
+		Hidden: true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runDaemon()
+		},
+	}
+}
+
+func runDaemon() error {
 	return fmt.Errorf(
 		"`docker daemon` is not supported on %s. Please run `dockerd` directly",
 		strings.Title(runtime.GOOS))

daemon_unix.go

@@ -3,23 +3,37 @@
 package main
 
 import (
+	"fmt"
+
 	"os"
 	"os/exec"
 	"path/filepath"
 	"syscall"
+
+	"github.com/spf13/cobra"
 )
 
-// CmdDaemon execs dockerd with the same flags
-func (p DaemonProxy) CmdDaemon(args ...string) error {
-	// Special case for handling `docker help daemon`. When pkg/mflag is removed
-	// we can support this on the daemon side, but that is not possible with
-	// pkg/mflag because it uses os.Exit(1) instead of returning an error on
-	// unexpected args.
-	if len(args) == 0 || args[0] != "--help" {
-		// Use os.Args[1:] so that "global" args are passed to dockerd
-		args = stripDaemonArg(os.Args[1:])
-	}
+const daemonBinary = "dockerd"
 
+func newDaemonCommand() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:    "daemon",
+		Hidden: true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runDaemon()
+		},
+	}
+	cmd.SetHelpFunc(helpFunc)
+	return cmd
+}
+
+// CmdDaemon execs dockerd with the same flags
+func runDaemon() error {
+	// Use os.Args[1:] so that "global" args are passed to dockerd
+	return execDaemon(stripDaemonArg(os.Args[1:]))
+}
+
+func execDaemon(args []string) error {
 	binaryPath, err := findDaemonBinary()
 	if err != nil {
 		return err
@@ -31,6 +45,12 @@ func (p DaemonProxy) CmdDaemon(args ...string) error {
 		os.Environ())
 }
 
+func helpFunc(cmd *cobra.Command, args []string) {
+	if err := execDaemon([]string{"--help"}); err != nil {
+		fmt.Fprintf(os.Stderr, "%s\n", err.Error())
+	}
+}
+
 // findDaemonBinary looks for the path to the dockerd binary starting with
 // the directory of the current executable (if one exists) and followed by $PATH
 func findDaemonBinary() (string, error) {

docker.go

@@ -12,64 +12,52 @@ import (
 	cliflags "github.com/docker/docker/cli/flags"
 	"github.com/docker/docker/cliconfig"
 	"github.com/docker/docker/dockerversion"
-	flag "github.com/docker/docker/pkg/mflag"
 	"github.com/docker/docker/pkg/term"
 	"github.com/docker/docker/utils"
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
 )
 
-var (
-	commonFlags = cliflags.InitCommonFlags()
-	clientFlags = initClientFlags(commonFlags)
-	flHelp      = flag.Bool([]string{"h", "-help"}, false, "Print usage")
-	flVersion   = flag.Bool([]string{"v", "-version"}, false, "Print version information and quit")
-)
+func newDockerCommand(dockerCli *client.DockerCli, opts *cliflags.ClientOptions) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:           "docker [OPTIONS] COMMAND [arg...]",
+		Short:         "A self-sufficient runtime for containers.",
+		SilenceUsage:  true,
+		SilenceErrors: true,
+		Args:          cli.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if opts.Version {
+				showVersion()
+				return nil
+			}
+			fmt.Fprintf(dockerCli.Err(), "\n"+cmd.UsageString())
+			return nil
+		},
+		PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+			dockerPreRun(cmd.Flags(), opts)
+			return dockerCli.Initialize(opts)
+		},
+	}
+	cobraadaptor.SetupRootCommand(cmd, dockerCli)
+
+	flags := cmd.Flags()
+	flags.BoolVarP(&opts.Version, "version", "v", false, "Print version information and quit")
+	flags.StringVar(&opts.ConfigDir, "config", cliconfig.ConfigDir(), "Location of client config files")
+	opts.Common.InstallFlags(flags)
+
+	return cmd
+}
 
 func main() {
 	// Set terminal emulation based on platform as required.
 	stdin, stdout, stderr := term.StdStreams()
-
 	logrus.SetOutput(stderr)
 
-	flag.Merge(flag.CommandLine, clientFlags.FlagSet, commonFlags.FlagSet)
+	opts := cliflags.NewClientOptions()
+	dockerCli := client.NewDockerCli(stdin, stdout, stderr, opts)
+	cmd := newDockerCommand(dockerCli, opts)
 
-	cobraAdaptor := cobraadaptor.NewCobraAdaptor(clientFlags)
-
-	flag.Usage = func() {
-		fmt.Fprint(stdout, "Usage: docker [OPTIONS] COMMAND [arg...]\n       docker [ --help | -v | --version ]\n\n")
-		fmt.Fprint(stdout, "A self-sufficient runtime for containers.\n\nOptions:\n")
-
-		flag.CommandLine.SetOutput(stdout)
-		flag.PrintDefaults()
-
-		help := "\nCommands:\n"
-
-		dockerCommands := append(cli.DockerCommandUsage, cobraAdaptor.Usage()...)
-		for _, cmd := range sortCommands(dockerCommands) {
-			help += fmt.Sprintf("    %-10.10s%s\n", cmd.Name, cmd.Description)
-		}
-
-		help += "\nRun 'docker COMMAND --help' for more information on a command."
-		fmt.Fprintf(stdout, "%s\n", help)
-	}
-
-	flag.Parse()
-
-	if *flVersion {
-		showVersion()
-		return
-	}
-
-	if *flHelp {
-		// if global flag --help is present, regardless of what other options and commands there are,
-		// just print the usage.
-		flag.Usage()
-		return
-	}
-
-	clientCli := client.NewDockerCli(stdin, stdout, stderr, clientFlags)
-
-	c := cli.New(clientCli, NewDaemonProxy(), cobraAdaptor)
-	if err := c.Run(flag.Args()...); err != nil {
+	if err := cmd.Execute(); err != nil {
 		if sterr, ok := err.(cli.StatusError); ok {
 			if sterr.Status != "" {
 				fmt.Fprintln(stderr, sterr.Status)
@@ -94,26 +82,22 @@ func showVersion() {
 	}
 }
 
-func initClientFlags(commonFlags *cliflags.CommonFlags) *cliflags.ClientFlags {
-	clientFlags := &cliflags.ClientFlags{FlagSet: new(flag.FlagSet), Common: commonFlags}
-	client := clientFlags.FlagSet
-	client.StringVar(&clientFlags.ConfigDir, []string{"-config"}, cliconfig.ConfigDir(), "Location of client config files")
+func dockerPreRun(flags *pflag.FlagSet, opts *cliflags.ClientOptions) {
+	opts.Common.SetDefaultOptions(flags)
+	cliflags.SetDaemonLogLevel(opts.Common.LogLevel)
 
-	clientFlags.PostParse = func() {
-		clientFlags.Common.PostParse()
-		cliflags.SetDaemonLogLevel(commonOpts.LogLevel)
-
-		if clientFlags.ConfigDir != "" {
-			cliconfig.SetConfigDir(clientFlags.ConfigDir)
+	// TODO: remove this, set a default in New, and pass it in opts
+	if opts.ConfigDir != "" {
+		cliconfig.SetConfigDir(opts.ConfigDir)
 	}
 
-		if clientFlags.Common.TrustKey == "" {
-			clientFlags.Common.TrustKey = filepath.Join(cliconfig.ConfigDir(), cliflags.DefaultTrustKeyFile)
+	if opts.Common.TrustKey == "" {
+		opts.Common.TrustKey = filepath.Join(
+			cliconfig.ConfigDir(),
+			cliflags.DefaultTrustKeyFile)
 	}
 
-		if clientFlags.Common.Debug {
+	if opts.Common.Debug {
 		utils.EnableDebug()
 	}
-	}
-	return clientFlags
 }

docker_test.go

@@ -6,13 +6,21 @@ import (
 
 	"github.com/Sirupsen/logrus"
 	"github.com/docker/docker/utils"
+
+	"github.com/docker/docker/api/client"
+	cliflags "github.com/docker/docker/cli/flags"
 )
 
 func TestClientDebugEnabled(t *testing.T) {
 	defer utils.DisableDebug()
 
-	clientFlags.Common.FlagSet.Parse([]string{"-D"})
-	clientFlags.PostParse()
+	opts := cliflags.NewClientOptions()
+	cmd := newDockerCommand(&client.DockerCli{}, opts)
+
+	opts.Common.Debug = true
+	if err := cmd.PersistentPreRunE(cmd, []string{}); err != nil {
+		t.Fatalf("Unexpected error: %s", err.Error())
+	}
 
 	if os.Getenv("DEBUG") != "1" {
 		t.Fatal("expected debug enabled, got false")