fixed router.ServeHTTP

added in middleware: Cors and Helmet

router.go

@@ -141,7 +141,16 @@ func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		panic("mux: method ServeHTTP called on nil")
 	}
 
-	r.mux.ServeHTTP(w, req)
+	h, pattern := r.mux.Handler(req)
+	if pattern == "" {
+		http.Error(w, "Not Found", http.StatusNotFound)
+		return
+	}
+
+	// ensure we run all the middlewares
+	h = stack(r.middlewares, h)
+	// serve
+	h.ServeHTTP(w, req)
 }
 
 // stack middlewares(http handler) in order they are passed (FIFO)