and nop notifier

backend/app/cmd/server.go

@@ -229,7 +229,7 @@ func (s *ServerCommand) newServerApp() (*serverApp, error) {
 	notifyService, err := s.makeNotify(dataService)
 	if err != nil {
 		log.Printf("[WARN] failed to make notify service, %s", err)
-		notifyService = nil // disable notifier
+		notifyService = notify.NopService // disable notifier
 	}
 
 	authProviders := s.makeAuthProviders(jwtService, avatarProxy, dataService)
@@ -474,7 +474,7 @@ func (s *ServerCommand) makeNotify(dataStore *service.DataStore) (*notify.Servic
 		}
 		return notify.NewService(dataStore, s.Notify.QueueSize, tg), nil
 	case "none":
-		return notify.NewService(dataStore, s.Notify.QueueSize), nil
+		return notify.NopService, nil
 	}
 	return nil, errors.Errorf("unsupported notification type %q", s.Notify.Type)
 }

backend/app/notify/notify.go

@@ -76,9 +76,11 @@ func (s *Service) Submit(comment store.Comment) {
 
 // Close queue channel and wait for completion
 func (s *Service) Close() {
-	close(s.queue)
-	s.cancel()
-	<-s.ctx.Done()
+	if s.queue != nil {
+		close(s.queue)
+		s.cancel()
+		<-s.ctx.Done()
+	}
 	s.closed = true
 }
 
@@ -97,3 +99,6 @@ func (s *Service) do() {
 		wg.Wait()
 	}
 }
+
+// NopService is do-nothing notifier, without destinations
+var NopService = &Service{}

backend/app/notify/notify_test.go

@@ -80,6 +80,13 @@ func TestService_Many(t *testing.T) {
 	assert.True(t, d2.closed)
 }
 
+func TestService_Nop(t *testing.T) {
+	s := NopService
+	s.Submit(store.Comment{})
+	s.Close()
+	assert.True(t, s.closed)
+}
+
 type mockDest struct {
 	data   []store.Comment
 	id     int