From 79649971c299f648fdd0ba3d4513a8cf7fc881d2 Mon Sep 17 00:00:00 2001
From: WooD Fung <5212215+wood1986@users.noreply.github.com>
Date: Tue, 20 Aug 2019 06:59:09 -0700
Subject: [PATCH] fix: add null check for connection.headers (#2200)

---
 lib/servers/SockJSServer.js              |  2 +-
 test/server/servers/SockJSServer.test.js | 15 +++++++++++++--
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/lib/servers/SockJSServer.js b/lib/servers/SockJSServer.js
index 782b325a48..c12913a5a7 100644
--- a/lib/servers/SockJSServer.js
+++ b/lib/servers/SockJSServer.js
@@ -64,7 +64,7 @@ module.exports = class SockJSServer extends BaseServer {
   // f should be passed the resulting connection and the connection headers
   onConnection(f) {
     this.socket.on('connection', (connection) => {
-      f(connection, connection.headers);
+      f(connection, connection ? connection.headers : null);
     });
   }
 
diff --git a/test/server/servers/SockJSServer.test.js b/test/server/servers/SockJSServer.test.js
index 9c61c67e14..48c535e98e 100644
--- a/test/server/servers/SockJSServer.test.js
+++ b/test/server/servers/SockJSServer.test.js
@@ -10,7 +10,7 @@ describe('SockJSServer', () => {
   let socketServer;
   let listeningApp;
 
-  beforeAll((done) => {
+  beforeEach((done) => {
     // eslint-disable-next-line new-cap
     const app = new express();
 
@@ -84,9 +84,20 @@ describe('SockJSServer', () => {
         done();
       }, 3000);
     });
+
+    it('should not throw an exception when connection is null', () => {
+      const cb = jest.fn();
+
+      socketServer.onConnection(cb);
+
+      expect(() => {
+        socketServer.socket.emit('connection', null);
+      }).not.toThrow();
+      expect(cb.mock.calls[0]).toEqual([null, null]);
+    });
   });
 
-  afterAll((done) => {
+  afterEach((done) => {
     listeningApp.close(done);
   });
 });