http: close http server gracefully.

pkg/api/http_server.go

@@ -25,6 +25,8 @@ type HttpServer struct {
 	macaron       *macaron.Macaron
 	context       context.Context
 	streamManager *live.StreamManager
+
+	httpSrv *http.Server
 }
 
 func NewHttpServer() *HttpServer {
@@ -46,11 +48,20 @@ func (hs *HttpServer) Start(ctx context.Context) error {
 	listenAddr := fmt.Sprintf("%s:%s", setting.HttpAddr, setting.HttpPort)
 	hs.log.Info("Initializing HTTP Server", "address", listenAddr, "protocol", setting.Protocol, "subUrl", setting.AppSubUrl)
 
+	hs.httpSrv = &http.Server{Addr: listenAddr, Handler: hs.macaron}
 	switch setting.Protocol {
 	case setting.HTTP:
-		err = http.ListenAndServe(listenAddr, hs.macaron)
+		err = hs.httpSrv.ListenAndServe()
+		if err == http.ErrServerClosed {
+			hs.log.Debug("server was shutdown gracefully")
+			return nil
+		}
 	case setting.HTTPS:
-		err = hs.listenAndServeTLS(listenAddr, setting.CertFile, setting.KeyFile)
+		err = hs.httpSrv.ListenAndServeTLS(setting.CertFile, setting.KeyFile)
+		if err == http.ErrServerClosed {
+			hs.log.Debug("server was shutdown gracefully")
+			return nil
+		}
 	default:
 		hs.log.Error("Invalid protocol", "protocol", setting.Protocol)
 		err = errors.New("Invalid Protocol")
@@ -59,6 +70,12 @@ func (hs *HttpServer) Start(ctx context.Context) error {
 	return err
 }
 
+func (hs *HttpServer) Shutdown(ctx context.Context) error {
+	err := hs.httpSrv.Shutdown(ctx)
+	hs.log.Info("stopped http server")
+	return err
+}
+
 func (hs *HttpServer) listenAndServeTLS(listenAddr, certfile, keyfile string) error {
 	if certfile == "" {
 		return fmt.Errorf("cert_file cannot be empty when using HTTPS")

pkg/cmd/grafana-server/server.go

@@ -3,7 +3,6 @@ package main
 import (
 	"context"
 	"os"
-	"time"
 
 	"golang.org/x/sync/errgroup"
 
@@ -39,6 +38,8 @@ type GrafanaServerImpl struct {
 	shutdownFn    context.CancelFunc
 	childRoutines *errgroup.Group
 	log           log.Logger
+
+	httpServer *api.HttpServer
 }
 
 func (g *GrafanaServerImpl) Start() {
@@ -74,9 +75,9 @@ func (g *GrafanaServerImpl) Start() {
 }
 
 func (g *GrafanaServerImpl) startHttpServer() {
-	httpServer := api.NewHttpServer()
+	g.httpServer = api.NewHttpServer()
 
-	err := httpServer.Start(g.context)
+	err := g.httpServer.Start(g.context)
 
 	if err != nil {
 		g.log.Error("Fail to start server", "error", err)
@@ -88,8 +89,13 @@ func (g *GrafanaServerImpl) startHttpServer() {
 func (g *GrafanaServerImpl) Shutdown(code int, reason string) {
 	g.log.Info("Shutdown started", "code", code, "reason", reason)
 
+	err := g.httpServer.Shutdown(g.context)
+	if err != nil {
+		g.log.Error("Failed to shutdown server", "error", err)
+	}
+
 	g.shutdownFn()
-	err := g.childRoutines.Wait()
+	err = g.childRoutines.Wait()
 
 	g.log.Info("Shutdown completed", "reason", err)
 	log.Close()