Merge pull request #19 from stefanprodan/metrics-port

Add option to run the metrics exporter on a different port

Author: stefanprodan

cmd/podinfo/main.go

@@ -21,6 +21,7 @@ func main() {
 	// flags definition
 	fs := pflag.NewFlagSet("default", pflag.ContinueOnError)
 	fs.Int("port", 9898, "port")
+	fs.Int("port-metrics", 0, "metrics port")
 	fs.String("level", "info", "log level debug, info, warn, error, flat or panic")
 	fs.String("backend-url", "", "backend service URL")
 	fs.Duration("http-client-timeout", 2*time.Minute, "client timeout duration")

pkg/api/server.go

@@ -33,6 +33,7 @@ type Config struct {
 	DataPath                  string        `mapstructure:"data-path"`
 	ConfigPath                string        `mapstructure:"config-path"`
 	Port                      string        `mapstructure:"port"`
+	PortMetrics               int           `mapstructure:"port-metrics"`
 	Hostname                  string        `mapstructure:"hostname"`
 	RandomDelay               bool          `mapstructure:"random-delay"`
 	RandomError               bool          `mapstructure:"random-error"`
@@ -96,6 +97,7 @@ func (s *Server) registerMiddlewares() {
 }
 
 func (s *Server) ListenAndServe(stopCh <-chan struct{}) {
+	go s.startMetricsServer()
 
 	s.registerHandlers()
 	s.registerMiddlewares()
@@ -157,6 +159,24 @@ func (s *Server) ListenAndServe(stopCh <-chan struct{}) {
 	}
 }
 
+func (s *Server) startMetricsServer() {
+	if s.config.PortMetrics > 0 {
+		mux := http.DefaultServeMux
+		mux.Handle("/metrics", promhttp.Handler())
+		mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
+			w.WriteHeader(http.StatusOK)
+			w.Write([]byte("OK"))
+		})
+
+		srv := &http.Server{
+			Addr:    fmt.Sprintf(":%v", s.config.PortMetrics),
+			Handler: mux,
+		}
+
+		srv.ListenAndServe()
+	}
+}
+
 func (s *Server) printRoutes() {
 	s.router.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error {
 		pathTemplate, err := route.GetPathTemplate()

pkg/version/version.go

@@ -1,4 +1,4 @@
 package version
 
-var VERSION = "1.5.1"
+var VERSION = "1.6.0"
 var REVISION = "unknown"