better ctrl command encapsulation (#23)

cmd/zrok/controller.go

@@ -10,31 +10,43 @@ import (
 )
 
 func init() {
-	rootCmd.AddCommand(controllerCmd)
+	rootCmd.AddCommand(newControllerCommand().cmd)
 }
 
-var controllerCmd = &cobra.Command{
-	Use:     "controller <configPath>",
-	Short:   "Start a zrok controller",
-	Aliases: []string{"ctrl"},
-	Run: func(_ *cobra.Command, args []string) {
-		tokens := strings.Split(endpoint, ":")
-		if len(tokens) != 2 {
-			panic(errors.Errorf("malformed endpoint '%v'", endpoint))
-		}
-		host := tokens[0]
-		port, err := strconv.Atoi(tokens[1])
-		if err != nil {
-			panic(err)
-		}
-		if err := controller.Run(&controller.Config{
-			Host: host,
-			Port: port,
-			Store: &store.Config{
-				Path: "zrok.db",
-			},
-		}); err != nil {
-			panic(err)
-		}
-	},
+type controllerCommand struct {
+	dbPath string
+	cmd    *cobra.Command
+}
+
+func newControllerCommand() *controllerCommand {
+	cmd := &cobra.Command{
+		Use:     "controller",
+		Short:   "Start a zrok controller",
+		Aliases: []string{"ctrl"},
+	}
+	ccmd := &controllerCommand{
+		cmd: cmd,
+	}
+	cmd.Run = ccmd.run
+	cmd.Flags().StringVarP(&ccmd.dbPath, "database", "d", "zrok.db", "Path to zrok controller database")
+	return ccmd
+}
+
+func (cmd *controllerCommand) run(_ *cobra.Command, _ []string) {
+	tokens := strings.Split(endpoint, ":")
+	if len(tokens) != 2 {
+		panic(errors.Errorf("malformed endpoint '%v'", endpoint))
+	}
+	host := tokens[0]
+	port, err := strconv.Atoi(tokens[1])
+	if err != nil {
+		panic(err)
+	}
+	if err := controller.Run(&controller.Config{
+		Host:  host,
+		Port:  port,
+		Store: &store.Config{Path: cmd.dbPath},
+	}); err != nil {
+		panic(err)
+	}
 }