Merge "camtool: added gsinit, was cmd/camgsinit. Better help too."

cmd/camtool/debug.go

@@ -53,6 +53,10 @@ func init() {
 	})
 }
 
+func (c *debugCmd) Describe() string {
+	return "Show misc meta-info from the given file."
+}
+
 func (c *debugCmd) Usage() {
 	var subModes, docs string
 	for k, v := range debugSubModes {

cmd/camtool/gsinit.go

@@ -19,15 +19,33 @@ package main
 import (
 	"bufio"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"os"
 	"strings"
 
 	"camlistore.org/pkg/blobserver/google"
+	"camlistore.org/pkg/cmdmain"
 	"camlistore.org/third_party/code.google.com/p/goauth2/oauth"
 )
 
-func main() {
+type gsinitCmd struct{}
+
+func init() {
+	cmdmain.RegisterCommand("gsinit", func(flags *flag.FlagSet) cmdmain.CommandRunner {
+		return new(gsinitCmd)
+	})
+}
+
+func (c *gsinitCmd) Describe() string {
+	return "Init Google Storage."
+}
+
+func (c *gsinitCmd) Usage() {
+	fmt.Fprintf(os.Stderr, "Usage: camtool [globalopts] gsinit \n")
+}
+
+func (c *gsinitCmd) RunCommand(args []string) error {
 	var (
 		err          error
 		clientId     string
@@ -35,16 +53,16 @@ func main() {
 	)
 
 	if clientId, clientSecret, err = getClientInfo(); err != nil {
-		panic(err)
+		return err
 	}
 	transport := google.MakeOauthTransport(clientId, clientSecret, "")
 
 	var accessCode string
 	if accessCode, err = getAccessCode(transport.Config); err != nil {
-		panic(err)
+		return err
 	}
 	if _, err = transport.Exchange(accessCode); err != nil {
-		panic(err)
+		return err
 	}
 
 	fmt.Printf("\nYour Google Storage auth object:\n\n")
@@ -56,6 +74,7 @@ func main() {
 	}
 	enc.Encode(authObj)
 	fmt.Print("\n")
+	return nil
 }
 
 // Prompt the user for an input line.  Return the given input.

cmd/camtool/sync.go

@@ -56,6 +56,10 @@ func init() {
 	})
 }
 
+func (c *syncCmd) Describe() string {
+	return "Synchronize blobs from a source to a destination."
+}
+
 func (c *syncCmd) Usage() {
 	fmt.Fprintf(os.Stderr, "Usage: camtool [globalopts] sync [syncopts] \n")
 }

pkg/cmdmain/cmdmain.go

@@ -81,6 +81,10 @@ type exampler interface {
 	Examples() []string
 }
 
+type describer interface {
+	Describe() string
+}
+
 // RegisterCommand adds a mode to the list of modes for the main command.
 // It is meant to be called in init() for each subcommand.
 func RegisterCommand(mode string, makeCmd func(Flags *flag.FlagSet) CommandRunner) {
@@ -149,16 +153,21 @@ func usage(msg string) {
 	Errf(`
 Usage: ` + cmdName + ` [globalopts] <mode> [commandopts] [commandargs]
 
-Examples:
+Modes:
+
 `)
 	for mode, cmd := range modeCommand {
-		Errf("\n")
+		if des, ok := cmd.(describer); ok {
+			Errf("  %s: %s\n", mode, des.Describe())
+		}
+	}
+	Errf("\nExamples:\n")
+	for mode, cmd := range modeCommand {
 		if ex, ok := cmd.(exampler); ok {
+			Errf("\n")
 			for _, example := range ex.Examples() {
 				Errf("  %s %s %s\n", cmdName, mode, example)
 			}
-		} else {
-			Errf("  %s %s ...\n", cmdName, mode)
 		}
 	}
 
@@ -173,6 +182,27 @@ Global options:
 	Exit(1)
 }
 
+func help(mode string) {
+	cmdName := os.Args[0]
+	// We can skip all the checks as they're done in Main
+	cmd := modeCommand[mode]
+	cmdFlags := modeFlags[mode]
+	if des, ok := cmd.(describer); ok {
+		Errf("%s\n", des.Describe())
+	}
+	Errf("\n")
+	cmd.Usage()
+	if hasFlags(cmdFlags) {
+		cmdFlags.PrintDefaults()
+	}
+	if ex, ok := cmd.(exampler); ok {
+		Errf("\nExamples:\n")
+		for _, example := range ex.Examples() {
+			Errf("  %s %s %s\n", cmdName, mode, example)
+		}
+	}
+}
+
 // Main is meant to be the core of a command that has
 // subcommands (modes), such as camput or camtool.
 func Main() error {
@@ -180,7 +210,7 @@ func Main() error {
 	flag.Parse()
 	args := flag.Args()
 	if *FlagVersion {
-		fmt.Fprintf(Stderr, "camput version: %s\n", buildinfo.Version())
+		fmt.Fprintf(Stderr, "%s version: %s\n", os.Args[0], buildinfo.Version())
 		return nil
 	}
 	if *FlagHelp {
@@ -197,10 +227,16 @@ func Main() error {
 	}
 
 	cmdFlags := modeFlags[mode]
+	var cmdHelp bool
+	cmdFlags.BoolVar(&cmdHelp, "help", false, "Help for this mode.")
 	err := cmdFlags.Parse(args[1:])
 	if err != nil {
 		err = ErrUsage
 	} else {
+		if cmdHelp {
+			help(mode)
+			return nil
+		}
 		err = cmd.RunCommand(cmdFlags.Args())
 	}
 	if ue, isUsage := err.(UsageError); isUsage {