Websocket: unhandle rejection (#6418)

* Websocket: unhandle rejection

Closes: https://github.com/parse-community/parse-server/issues/6413, https://github.com/parse-community/parse-server/issues/6173
Prevent crashing on websocket error.

Bonus points to anybody who can post a specific payload that the client sends that returns an error.

* log the socket

* fix tests

* fix payload reference link

spec/ParseLiveQuery.spec.js

@@ -24,6 +24,43 @@ describe('ParseLiveQuery', function() {
     await object.save();
   });
 
+  it('handle invalid websocket payload length', async done => {
+    await reconfigureServer({
+      liveQuery: {
+        classNames: ['TestObject'],
+      },
+      startLiveQueryServer: true,
+      verbose: false,
+      silent: true,
+      websocketTimeout: 100,
+    });
+    const object = new TestObject();
+    await object.save();
+
+    const query = new Parse.Query(TestObject);
+    query.equalTo('objectId', object.id);
+    const subscription = await query.subscribe();
+
+    // All control frames must have a payload length of 125 bytes or less.
+    // https://tools.ietf.org/html/rfc6455#section-5.5
+    //
+    // 0x89 = 10001001 = ping
+    // 0xfe = 11111110 = first bit is masking the remaining 7 are 1111110 or 126 the payload length
+    // https://tools.ietf.org/html/rfc6455#section-5.2
+    const client = await Parse.CoreManager.getLiveQueryController().getDefaultLiveQueryClient();
+    client.socket._socket.write(Buffer.from([0x89, 0xfe]));
+
+    subscription.on('update', async object => {
+      expect(object.get('foo')).toBe('bar');
+      done();
+    });
+    // Wait for Websocket timeout to reconnect
+    setTimeout(async () => {
+      object.set({ foo: 'bar' });
+      await object.save();
+    }, 1000);
+  });
+
   afterEach(async function(done) {
     const client = await Parse.CoreManager.getLiveQueryController().getDefaultLiveQueryClient();
     client.close();

spec/ParseWebSocketServer.spec.js

@@ -1,11 +1,12 @@
 const {
   ParseWebSocketServer,
 } = require('../lib/LiveQuery/ParseWebSocketServer');
+const EventEmitter = require('events');
 
 describe('ParseWebSocketServer', function() {
   beforeEach(function(done) {
     // Mock ws server
-    const EventEmitter = require('events');
+
     const mockServer = function() {
       return new EventEmitter();
     };
@@ -22,11 +23,11 @@ describe('ParseWebSocketServer', function() {
       onConnectCallback,
       { websocketTimeout: 5 }
     ).server;
-    const ws = {
-      readyState: 0,
-      OPEN: 0,
-      ping: jasmine.createSpy('ping'),
-    };
+    const ws = new EventEmitter();
+    ws.readyState = 0;
+    ws.OPEN = 0;
+    ws.ping = jasmine.createSpy('ping');
+
     parseWebSocketServer.onConnection(ws);
 
     // Make sure callback is called

src/LiveQuery/ParseWebSocketServer.js

@@ -13,6 +13,10 @@ export class ParseWebSocketServer {
       logger.info('Parse LiveQuery Server starts running');
     };
     wss.onConnection = ws => {
+      ws.on('error', error => {
+        logger.error(error.message);
+        logger.error(JSON.stringify(ws));
+      });
       onConnect(new ParseWebSocket(ws));
       // Send ping to client periodically
       const pingIntervalId = setInterval(() => {