UI: make stop load test button works

pkg/server/server.go

@@ -66,6 +66,7 @@ func (s *Server) setupRouter() (*httprouter.Router, error) {
 	router.GET("/cluster/join", s.acceptWorkerConn)
 	router.GET("/notifications", s.acceptNotificationConn)
 	router.POST("/api/v1/load_test", s.handleStartLoadTest)
+	router.DELETE("/api/v1/load_test", s.handleStopLoadTest)
 
 	// CORS
 	router.GlobalOPTIONS = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -159,6 +160,11 @@ func (s *Server) StartLoadTest(r *messages.StartLoadTestRequest) {
 	s.GetWorkerService().BroadcastMessageToWorkers(envelope)
 }
 
+func (s *Server) StopLoadTest() {
+	envelope, _ := json.Marshal(messages.Envelope{Kind: messages.KindStopLoadTestRequest})
+	s.GetWorkerService().BroadcastMessageToWorkers(envelope)
+}
+
 func (s *Server) watchWorkerStateChange() {
 	for {
 		<-s.workerService.stateUpdatedCh
@@ -221,3 +227,12 @@ func (s *Server) handleStartLoadTest(responseWriter http.ResponseWriter, req *ht
 	responseWriter.WriteHeader(200)
 	responseWriter.Write([]byte("ok"))
 }
+
+func (s *Server) handleStopLoadTest(responseWriter http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	s.StopLoadTest()
+
+	header := responseWriter.Header()
+	header.Set("Access-Control-Allow-Origin", "*")
+
+	responseWriter.WriteHeader(204)
+}

pkg/worker/worker.go

@@ -150,12 +150,18 @@ func (h *defaultMessageHandler) HandleMessage(message []byte) {
 			Body:   []byte(req.Body),
 		})
 
+		h.worker.resetLoadTest()
 		go h.worker.startLoadTest(targeter, rate, duration, "terjang")
 	} else if envelope.Kind == messages.KindStopLoadTestRequest {
 		h.worker.stopLoadTest()
 	}
 }
 
+func (w *Worker) resetLoadTest() {
+	w.attacker = vegeta.NewAttacker()
+	w.metrics = vegeta.Metrics{}
+}
+
 func (w *Worker) startLoadTest(tr vegeta.Targeter, p vegeta.Pacer, du time.Duration, name string) {
 	w.loadTestState = messages.WorkerStateRunning
 	w.sendWorkerInfoToServer()
@@ -164,14 +170,17 @@ func (w *Worker) startLoadTest(tr vegeta.Targeter, p vegeta.Pacer, du time.Durat
 		w.metrics.Add(res)
 	}
 
-	w.loadTestState = messages.WorkerStateDone
+	// Preserves state if it's stopped
+	if w.loadTestState != messages.WorkerStateStopped {
+		w.loadTestState = messages.WorkerStateDone
+	}
+
 	w.sendWorkerInfoToServer()
 }
 
 func (w *Worker) stopLoadTest() {
-	w.attacker.Stop()
-
 	w.loadTestState = messages.WorkerStateStopped
+	w.attacker.Stop()
 }
 
 func (w *Worker) LoopSendMetricsToServer() {