add start metrics server

weed/command/s3.go

@@ -23,12 +23,13 @@ var (
 )
 
 type S3Options struct {
-	filer          *string
-	port           *int
-	config         *string
-	domainName     *string
-	tlsPrivateKey  *string
-	tlsCertificate *string
+	filer           *string
+	port            *int
+	config          *string
+	domainName      *string
+	tlsPrivateKey   *string
+	tlsCertificate  *string
+	metricsHttpPort *int
 }
 
 func init() {
@@ -39,6 +40,7 @@ func init() {
 	s3StandaloneOptions.config = cmdS3.Flag.String("config", "", "path to the config file")
 	s3StandaloneOptions.tlsPrivateKey = cmdS3.Flag.String("key.file", "", "path to the TLS private key file")
 	s3StandaloneOptions.tlsCertificate = cmdS3.Flag.String("cert.file", "", "path to the TLS certificate file")
+	s3StandaloneOptions.metricsHttpPort = cmdS3.Flag.Int("metricsPort", 0, "Prometheus metrics listen port")
 }
 
 var cmdS3 = &Command{
@@ -153,6 +155,7 @@ func (s3opt *S3Options) startS3Server() bool {
 		}
 	}
 
+	go stats_collect.StartMetricsServer(stats_collect.S3Gather, *s3opt.metricsHttpPort)
 	go stats_collect.LoopPushingMetric("s3", stats_collect.SourceName(uint32(*s3opt.port)), stats_collect.S3Gather, metricsAddress, metricsIntervalSec)
 
 	router := mux.NewRouter().SkipClean(true)
@@ -169,7 +172,6 @@ func (s3opt *S3Options) startS3Server() bool {
 	if s3ApiServer_err != nil {
 		glog.Fatalf("S3 API Server startup error: %v", s3ApiServer_err)
 	}
-
 	httpS := &http.Server{Handler: router}
 
 	listenAddress := fmt.Sprintf(":%d", *s3opt.port)