mux: run http server if gateway | grpcWeb | react | mux is defined

goroutines: use errgroup
Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

go.mod

@@ -36,6 +36,7 @@ require (
 	go.linka.cloud/protofilters v0.5.0
 	go.uber.org/multierr v1.7.0
 	golang.org/x/net v0.8.0
+	golang.org/x/sync v0.1.0
 	google.golang.org/genproto v0.0.0-20230306155012-7f2fa6fef1f4
 	google.golang.org/grpc v1.53.0
 	google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.3.0

go.sum

@@ -333,7 +333,6 @@ github.com/grpc-ecosystem/go-grpc-middleware v1.2.2/go.mod h1:EaizFBKfUKtMIF5iaD
 github.com/grpc-ecosystem/go-grpc-middleware v1.3.0 h1:+9834+KizmvFV7pXQGSXQTsaWhq2GjuNUt0aUU0YBYw=
 github.com/grpc-ecosystem/go-grpc-middleware v1.3.0/go.mod h1:z0ButlSOZa5vEBq9m2m2hlwIgKw+rp3sdCBRoJY+30Y=
 github.com/grpc-ecosystem/grpc-gateway v1.9.5/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
-github.com/grpc-ecosystem/grpc-gateway v1.16.0 h1:gmcG1KaJ57LophUzW0Hy8NmPhnMZb4M0+kPpLofRdBo=
 github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
 github.com/grpc-ecosystem/grpc-opentracing v0.0.0-20180507213350-8e809c8a8645 h1:MJG/KsmcqMwFAkh8mTnAwhyKoB+sTAnY4CACC110tbU=
 github.com/grpc-ecosystem/grpc-opentracing v0.0.0-20180507213350-8e809c8a8645/go.mod h1:6iZfnjpejD4L/4DwD7NryNaJyCQdzwWwH2MWhCA90Kw=
@@ -886,6 +885,7 @@ golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180823144017-11551d06cbcc/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

service/gateway.go

@@ -22,9 +22,9 @@ func (s *service) gateway(opts ...runtime.ServeMuxOption) error {
 		return err
 	}
 	if s.opts.gatewayPrefix != "" {
-		s.opts.mux.Handle(s.opts.gatewayPrefix+"/", http.StripPrefix(s.opts.gatewayPrefix, wsproxy.WebsocketProxy(mux)))
+		s.lazyMux().Handle(s.opts.gatewayPrefix+"/", http.StripPrefix(s.opts.gatewayPrefix, wsproxy.WebsocketProxy(mux)))
 	} else {
-		s.opts.mux.Handle("/", wsproxy.WebsocketProxy(mux))
+		s.lazyMux().Handle("/", wsproxy.WebsocketProxy(mux))
 	}
 	return nil
 }

service/service.go

@@ -21,6 +21,7 @@ import (
 	"github.com/rs/cors"
 	"github.com/soheilhy/cmux"
 	"go.uber.org/multierr"
+	"golang.org/x/sync/errgroup"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/health"
 	"google.golang.org/grpc/health/grpc_health_v1"
@@ -84,9 +85,6 @@ func newService(opts ...Option) (*service, error) {
 		s.opts.streamClientInterceptors = append([]grpc.StreamClientInterceptor{md.StreamClientInterceptor()}, s.opts.streamClientInterceptors...)
 	}
 
-	if s.opts.mux == nil {
-		s.opts.mux = http.NewServeMux()
-	}
 	if s.opts.error != nil {
 		return nil, s.opts.error
 	}
@@ -186,8 +184,6 @@ func (s *service) run() error {
 	}
 	s.running = true
 
-	errs := make(chan error, 3)
-
 	if reflect.DeepEqual(s.opts.cors, cors.Options{}) {
 		s.opts.cors = cors.Options{
 			AllowedHeaders: []string{"*"},
@@ -204,31 +200,26 @@ func (s *service) run() error {
 			AllowCredentials: true,
 		}
 	}
-	hServer := &http.Server{
-		Handler: alice.New(s.opts.middlewares...).Then(cors.New(s.opts.cors).Handler(s.opts.mux)),
-	}
-	if s.opts.Gateway() || s.opts.grpcWeb || s.opts.hasReactUI {
-		go func() {
-			errs <- hServer.Serve(hList)
-			hServer.Shutdown(s.opts.ctx)
-		}()
-	}
-	go func() {
-		errs <- s.server.Serve(gLis)
-	}()
 
-	go func() {
+	g, ctx := errgroup.WithContext(s.opts.ctx)
-		if err := mux.Serve(); err != nil {
+	if s.opts.mux != nil {
-			// TODO(adphi): find more elegant solution
+		hServer := &http.Server{
-			if ignoreMuxError(err) {
+			Handler: alice.New(s.opts.middlewares...).Then(cors.New(s.opts.cors).Handler(s.opts.mux)),
-				errs <- nil
-				return
-			}
-			errs <- err
-			return
 		}
-		errs <- nil
+		g.Go(func() error {
-	}()
+			defer hServer.Shutdown(ctx)
+			return hServer.Serve(hList)
+		})
+	}
+
+	g.Go(func() error {
+		return s.server.Serve(gLis)
+	})
+
+	g.Go(func() error {
+		return ignoreMuxError(mux.Serve())
+	})
+
 	if s.healthServer != nil {
 		for k := range s.services {
 			s.healthServer.SetServingStatus(k, grpc_health_v1.HealthCheckResponse_SERVING)
@@ -250,13 +241,18 @@ func (s *service) run() error {
 	}
 	s.mu.Unlock()
 	sigs := s.notify()
+
+	errs := make(chan error, 1)
+	go func() {
+		errs <- g.Wait()
+	}()
 	select {
 	case sig := <-sigs:
 		fmt.Println()
 		logger.C(s.opts.ctx).Warnf("received %v", sig)
 		return s.Close()
 	case err := <-errs:
-		if err != nil && !ignoreMuxError(err) {
+		if !isMuxError(err) {
 			logger.C(s.opts.ctx).Error(err)
 			return err
 		}
@@ -394,10 +390,27 @@ func (s *service) notify() <-chan os.Signal {
 	return sigs
 }
 
-func ignoreMuxError(err error) bool {
+func (s *service) lazyMux() ServeMux {
+	if s.opts.mux == nil {
+		s.opts.mux = http.NewServeMux()
+	}
+	return s.opts.mux
+}
+
+func ignoreMuxError(err error) error {
+	if !isMuxError(err) {
+		return err
+	}
+	return nil
+}
+
+func isMuxError(err error) bool {
 	if err == nil {
+		return false
+	}
+	if strings.Contains(err.Error(), "use of closed network connection") ||
+		strings.Contains(err.Error(), "mux: server closed") {
 		return true
 	}
-	return strings.Contains(err.Error(), "use of closed network connection") ||
+	return false
-		strings.Contains(err.Error(), "mux: server closed")
 }

service/web.go

@@ -28,9 +28,9 @@ func (s *service) grpcWeb(opts ...grpcweb.Option) error {
 	h := grpcweb.WrapServer(s.server, append(defaultWebOptions, opts...)...)
 	for _, v := range grpcweb.ListGRPCResources(s.server) {
 		if s.opts.grpcWebPrefix != "" {
-			s.opts.mux.Handle(s.opts.grpcWebPrefix+v, http.StripPrefix(s.opts.grpcWebPrefix, h))
+			s.lazyMux().Handle(s.opts.grpcWebPrefix+v, http.StripPrefix(s.opts.grpcWebPrefix, h))
 		} else {
-			s.opts.mux.Handle(v, h)
+			s.lazyMux().Handle(v, h)
 		}
 	}
 	return nil
@@ -44,6 +44,6 @@ func (s *service) reactApp() error {
 	if err != nil {
 		return err
 	}
-	s.opts.mux.Handle("/", h)
+	s.lazyMux().Handle("/", h)
 	return nil
 }