From 1a20c70c41a5f4a7c1e2612f538ea48070bdbfb2 Mon Sep 17 00:00:00 2001
From: Sebastian Serth <Sebastian.Serth@hpi.de>
Date: Thu, 29 Oct 2020 12:45:40 +0100
Subject: [PATCH] Send WebSocket messages only if connected

---
 app/assets/javascripts/editor/websocket.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/app/assets/javascripts/editor/websocket.js b/app/assets/javascripts/editor/websocket.js
index 1bc26648..09d64975 100644
--- a/app/assets/javascripts/editor/websocket.js
+++ b/app/assets/javascripts/editor/websocket.js
@@ -86,7 +86,11 @@ CommandSocket.prototype.executeCommand = function(cmd) {
  * @param data
  */
 CommandSocket.prototype.send = function(data) {
-  this.websocket.send(data);
+  // Only send message if WebSocket is open and ready.
+  // Ignore all other messages (they might hit a wrong container anyway)
+  if (this.getReadyState() === this.websocket.OPEN) {
+    this.websocket.send(data);
+  }
 };
 
 /**