add subcommand version

cli/cmd/root.go

@@ -14,7 +14,7 @@ var cfgFile string
 // rootCmd represents the base command when called without any subcommands
 var rootCmd = &cobra.Command{
 	Use:   "filebrowser",
-	Version: "someversion",
+	Version: "(untracked)",
 	Short: "A stylish web-based file manager",
 	Long: `File Browser is static binary composed of a golang backend
 and a Vue.js frontend to create, edit, copy, move, download your files
@@ -37,6 +37,7 @@ func Execute() {
 
 func init() {
 	cobra.OnInitialize(initConfig)
+	rootCmd.SetVersionTemplate("File Browser {{printf \"version %s\" .Version}}\n")
 
 	rootCmd.PersistentFlags().StringVarP(&cfgFile, "config", "c", "", "config file (default is $HOME/.cli.yaml)")
 

cli/cmd/version.go

@@ -0,0 +1,25 @@
+package cmd
+
+import (
+	"text/template"
+	"github.com/spf13/cobra"
+)
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Print the version number of File Browser",
+	Long:  `All software has versions. This is File Browser's`,
+	Run: func(cmd *cobra.Command, args []string) {
+		// https://github.com/spf13/cobra/issues/724
+		t := template.New("version")
+		template.Must(t.Parse(rootCmd.VersionTemplate()))
+		err := t.Execute(rootCmd.OutOrStdout(), rootCmd)
+		if err != nil {
+			rootCmd.Println(err)
+		}
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+}