From 38ec30bc2efb0edc525ab733f5a3b9ceb0274fad Mon Sep 17 00:00:00 2001
From: Rafael Oleza <rafeca@fb.com>
Date: Fri, 29 Sep 2017 17:56:26 -0700
Subject: [PATCH] Fix error appearing when disconnecting HMR client

Reviewed By: cpojer

Differential Revision: D5944285

fbshipit-source-id: 5751f6ad2b999872aa3d33e1c7fca105b3156da4
---
 local-cli/server/util/attachWebsocketServer.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/local-cli/server/util/attachWebsocketServer.js b/local-cli/server/util/attachWebsocketServer.js
index ae9efed0f..fcbe0f719 100644
--- a/local-cli/server/util/attachWebsocketServer.js
+++ b/local-cli/server/util/attachWebsocketServer.js
@@ -47,9 +47,14 @@ function attachWebsocketServer<TClient: Object>({
   });
 
   wss.on('connection', async ws => {
+    let connected = true;
     const url = ws.upgradeReq.url;
 
-    const sendFn = ws.send.bind(ws);
+    const sendFn = (...args) => {
+      if (connected) {
+        ws.send(...args);
+      }
+    };
 
     const client = await websocketServer.onClientConnect(url, sendFn);
 
@@ -60,6 +65,7 @@ function attachWebsocketServer<TClient: Object>({
     ws.on('close', () => {
       websocketServer.onClientDisconnect &&
         websocketServer.onClientDisconnect(client);
+      connected = false;
     });
 
     ws.on('message', message => {