Implement WebSocketServer Adapter (parse-community#5866)

* Implement WebSocketServerAdapter

* lint

* clean up

Author: dplewis

spec/ParseWebSocket.spec.js

@@ -9,26 +9,26 @@ describe('ParseWebSocket', function() {
     expect(parseWebSocket.ws).toBe(ws);
   });
 
-  it('can handle events defined in typeMap', function() {
+  it('can handle disconnect event', function(done) {
     const ws = {
-      on: jasmine.createSpy('on'),
+      onclose: () => {},
     };
-    const callback = {};
     const parseWebSocket = new ParseWebSocket(ws);
-    parseWebSocket.on('disconnect', callback);
-
-    expect(parseWebSocket.ws.on).toHaveBeenCalledWith('close', callback);
+    parseWebSocket.on('disconnect', () => {
+      done();
+    });
+    ws.onclose();
   });
 
-  it('can handle events which are not defined in typeMap', function() {
+  it('can handle message event', function(done) {
     const ws = {
-      on: jasmine.createSpy('on'),
+      onmessage: () => {},
     };
-    const callback = {};
     const parseWebSocket = new ParseWebSocket(ws);
-    parseWebSocket.on('open', callback);
-
-    expect(parseWebSocket.ws.on).toHaveBeenCalledWith('open', callback);
+    parseWebSocket.on('message', () => {
+      done();
+    });
+    ws.onmessage();
   });
 
   it('can send a message', function() {

spec/ParseWebSocketServer.spec.js

@@ -1,5 +1,4 @@
-const ParseWebSocketServer = require('../lib/LiveQuery/ParseWebSocketServer')
-  .ParseWebSocketServer;
+const { ParseWebSocketServer } = require('../lib/LiveQuery/ParseWebSocketServer');
 
 describe('ParseWebSocketServer', function() {
   beforeEach(function(done) {
@@ -19,14 +18,14 @@ describe('ParseWebSocketServer', function() {
     const parseWebSocketServer = new ParseWebSocketServer(
       server,
       onConnectCallback,
-      5
+      { websocketTimeout: 5 }
     ).server;
     const ws = {
       readyState: 0,
       OPEN: 0,
       ping: jasmine.createSpy('ping'),
     };
-    parseWebSocketServer.emit('connection', ws);
+    parseWebSocketServer.onConnection(ws);
 
     // Make sure callback is called
     expect(onConnectCallback).toHaveBeenCalled();

src/Adapters/WebSocketServer/WSAdapter.js

@@ -0,0 +1,22 @@
+/*eslint no-unused-vars: "off"*/
+import { WSSAdapter } from './WSSAdapter';
+const WebSocketServer = require('ws').Server;
+
+/**
+ * Wrapper for ws node module
+ */
+export class WSAdapter extends WSSAdapter {
+  constructor(options: any) {
+    super(options);
+    const wss = new WebSocketServer({ server: options.server });
+    wss.on('listening', this.onListen);
+    wss.on('connection', this.onConnection);
+  }
+
+  onListen() {}
+  onConnection(ws) {}
+  start() {}
+  close() {}
+}
+
+export default WSAdapter;

src/Adapters/WebSocketServer/WSSAdapter.js

@@ -0,0 +1,52 @@
+/*eslint no-unused-vars: "off"*/
+// WebSocketServer Adapter
+//
+// Adapter classes must implement the following functions:
+// * onListen()
+// * onConnection(ws)
+// * start()
+// * close()
+//
+// Default is WSAdapter. The above functions will be binded.
+
+/**
+ * @module Adapters
+ */
+/**
+ * @interface WSSAdapter
+ */
+export class WSSAdapter {
+  /**
+   * @param {Object} options - {http.Server|https.Server} server
+   */
+  constructor(options) {
+    this.onListen = () => {}
+    this.onConnection = () => {}
+  }
+
+  // /**
+  //  * Emitted when the underlying server has been bound.
+  //  */
+  // onListen() {}
+
+  // /**
+  //  * Emitted when the handshake is complete.
+  //  *
+  //  * @param {WebSocket} ws - RFC 6455 WebSocket.
+  //  */
+  // onConnection(ws) {}
+
+  /**
+   * Initialize Connection.
+   *
+   * @param {Object} options
+   */
+  start(options) {}
+
+  /**
+   * Closes server.
+   */
+  close() {}
+}
+
+export default WSSAdapter;

src/LiveQuery/ParseLiveQueryServer.js

@@ -61,7 +61,7 @@ class ParseLiveQueryServer {
     this.parseWebSocketServer = new ParseWebSocketServer(
       server,
       parseWebsocket => this._onConnect(parseWebsocket),
-      config.websocketTimeout
+      config
     );
 
     // Initialize subscriber

src/LiveQuery/ParseWebSocketServer.js

@@ -1,24 +1,26 @@
+import { loadAdapter } from '../Adapters/AdapterLoader';
+import { WSAdapter } from '../Adapters/WebSocketServer/WSAdapter';
 import logger from '../logger';
-
-const typeMap = new Map([['disconnect', 'close']]);
-const getWS = function(){
-  return require('ws');
-};
+import events from 'events';
 
 export class ParseWebSocketServer {
   server: Object;
 
   constructor(
     server: any,
     onConnect: Function,
-    websocketTimeout: number = 10 * 1000
+    config
   ) {
-    const WebSocketServer = getWS().Server;
-    const wss = new WebSocketServer({ server: server });
-    wss.on('listening', () => {
+    config.server = server;
+    const wss = loadAdapter(
+      config.wssAdapter,
+      WSAdapter,
+      config,
+    );
+    wss.onListen = () => {
       logger.info('Parse LiveQuery Server starts running');
-    });
-    wss.on('connection', ws => {
+    };
+    wss.onConnection = (ws) => {
       onConnect(new ParseWebSocket(ws));
       // Send ping to client periodically
       const pingIntervalId = setInterval(() => {
@@ -27,24 +29,29 @@ export class ParseWebSocketServer {
         } else {
           clearInterval(pingIntervalId);
         }
-      }, websocketTimeout);
-    });
+      }, config.websocketTimeout || 10 * 1000);
+    };
+    wss.start();
     this.server = wss;
   }
+
+  close() {
+    if (this.server && this.server.close) {
+      this.server.close();
+    }
+  }
 }
 
-export class ParseWebSocket {
+export class ParseWebSocket extends events.EventEmitter {
   ws: any;
 
   constructor(ws: any) {
+    super();
+    ws.onmessage = (request) => this.emit('message', request);
+    ws.onclose = () => this.emit('disconnect');
     this.ws = ws;
   }
 
-  on(type: string, callback): void {
-    const wsType = typeMap.has(type) ? typeMap.get(type) : type;
-    this.ws.on(wsType, callback);
-  }
-
   send(message: any): void {
     this.ws.send(message);
   }