add event cache. sending all cached event when new websocket connection establish

plugin/wshub/events.go

@@ -14,3 +14,9 @@ type EventDataReceived struct {
 	EventID event.EventId
 	Data    json.RawMessage
 }
+
+var eventCache []*EventData
+
+func init() {
+	eventCache = make([]*EventData, 0)
+}

plugin/wshub/server.go

@@ -112,6 +112,20 @@ func (s *wsServer) handleWsInfo(w http.ResponseWriter, r *http.Request) {
 	s.register(client)
 	defer s.unregister(client)
 	go client.start()
+	// send initial data
+	for _, data := range eventCache {
+		// ignore empty
+		if data.EventID == "" {
+			continue
+		}
+		eventCacheData, _ := json.Marshal(data)
+		err := client.conn.WriteMessage(websocket.TextMessage, eventCacheData)
+		if err != nil {
+			s.log.Warn("write message failed", err)
+			return
+		}
+	}
+	// start message loop
 	for {
 		select {
 		case data := <-client.Data:

plugin/wshub/wshub.go

@@ -162,19 +162,25 @@ func (w *WsHub) CreatePanel() fyne.CanvasObject {
 }
 
 func (w *WsHub) registerEvents() {
+	i := 0
 	for eid, _ := range events.EventsMapping {
+		eventCache = append(eventCache, &EventData{})
+		currentIdx := i
 		global.EventManager.RegisterA(eid,
 			"plugin.wshub.event."+string(eid),
 			func(e *event.Event) {
-				val, err := json.Marshal(EventData{
+				ed := EventData{
 					EventID: e.Id,
 					Data:    e.Data,
-				})
+				}
+				val, err := json.Marshal(ed)
 				if err != nil {
 					w.log.Errorf("failed to marshal event data %v", err)
 					return
 				}
+				eventCache[currentIdx] = &ed
 				w.server.broadcast(val)
 			})
+		i++
 	}
 }