check origin unnecessary for demo

main.go

@@ -42,12 +42,15 @@ func load_data(filename string) []dashData {
 	return d
 }
 
-var upgrader = websocket.Upgrader{}
+var upgrader = websocket.Upgrader{
+	CheckOrigin: func(r *http.Request) bool {
+		return true
+	},
+}
 
 func main() {
 	http.HandleFunc("/ws", subscribe)
 	log.Fatal(http.ListenAndServe("localhost:9888", nil))
-
 }
 
 func subscribe(w http.ResponseWriter, r *http.Request) {