Add version command

Author: dsxack

cmd/gitfs/root.go

@@ -11,4 +11,5 @@ var rootCmd = &cobra.Command{
 func init() {
 	rootCmd.AddCommand(mountCmd)
 	rootCmd.AddCommand(umountCmd)
+	rootCmd.AddCommand(versionCmd)
 }

cmd/gitfs/version.go

@@ -0,0 +1,39 @@
+package main
+
+import (
+	"fmt"
+	"github.com/spf13/cobra"
+	"runtime/debug"
+	"time"
+)
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Print version information",
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println(getVersionString())
+	},
+}
+
+func getVersionString() string {
+	info, ok := debug.ReadBuildInfo()
+	if ok {
+		return "gitfs: unknown version"
+	}
+	var revision string
+	var lastCommit time.Time
+
+	for _, kv := range info.Settings {
+		switch kv.Key {
+		case "vcs.revision":
+			revision = kv.Value
+		case "vcs.time":
+			lastCommit, _ = time.Parse(time.RFC3339, kv.Value)
+		}
+	}
+	return fmt.Sprintf(
+		"gitfs: version %s, build %s",
+		revision,
+		lastCommit,
+	)
+}