server/cmd: add flag to print version information (#369)

cmd/pd-server/main.go

@@ -28,6 +28,12 @@ import (
 func main() {
 	cfg := server.NewConfig()
 	err := cfg.Parse(os.Args[1:])
+
+	if cfg.Version {
+		server.PrintPDInfo()
+		os.Exit(0)
+	}
+
 	switch errors.Cause(err) {
 	case nil:
 	case flag.ErrHelp:
@@ -42,7 +48,7 @@ func main() {
 		log.Fatalf("initalize logger err %s\n", err)
 	}
 
-	server.PrintPDInfo()
+	server.LogPDInfo()
 
 	server.PushMetric(cfg)
 

server/config.go

@@ -33,6 +33,8 @@ import (
 type Config struct {
 	*flag.FlagSet `json:"-"`
 
+	Version bool
+
 	ClientUrls          string `toml:"client-urls" json:"client-urls"`
 	PeerUrls            string `toml:"peer-urls" json:"peer-urls"`
 	AdvertiseClientUrls string `toml:"advertise-client-urls" json:"advertise-client-urls"`
@@ -84,6 +86,7 @@ func NewConfig() *Config {
 	cfg.FlagSet = flag.NewFlagSet("pd", flag.ContinueOnError)
 	fs := cfg.FlagSet
 
+	fs.BoolVar(&cfg.Version, "v", false, "print version information and exit")
 	fs.StringVar(&cfg.configFile, "config", "", "Config file")
 
 	fs.Uint64Var(&cfg.ClusterID, "cluster-id", 0, "initial cluster ID for the pd cluster")

server/util.go

@@ -44,14 +44,20 @@ var (
 	PDGitHash = "None"
 )
 
-// PrintPDInfo prints the PD version information.
-func PrintPDInfo() {
+// LogPDInfo prints the PD version information.
+func LogPDInfo() {
 	log.Infof("Welcome to Placement Driver (PD).")
 	log.Infof("Version:")
 	log.Infof("Git Commit Hash: %s", PDGitHash)
 	log.Infof("UTC Build Time:  %s", PDBuildTS)
 }
 
+// PrintPDInfo prints the PD version information without log info.
+func PrintPDInfo() {
+	fmt.Println("Git Commit Hash:", PDGitHash)
+	fmt.Println("UTC Build Time: ", PDBuildTS)
+}
+
 const zeroDuration = time.Duration(0)
 
 // PushMetric pushs metircs in background.