Revise transport Socket.io@3/4 (#6188)

* feat :migrate socket.io 2 -> 3

* fix: backend test

* fix: ts error

* rm

* reset the test timeout

* fix: socket transports

* fix: ts

* fix: merge

* fix: merge

* resolve merge

* clean

* clean

src/node/handler/PadMessageHandler.ts

@@ -957,6 +957,7 @@ const handleClientReady = async (socket:any, message: typeof ChatMessage) => {
         rev: pad.getHeadRevisionNumber(),
         time: currentTime,
       },
+      socketTransportProtocols: settings.socketTransportProtocols,
       colorPalette: authorManager.getColorPalette(),
       clientIp: '127.0.0.1',
       userColor: authorColorId,

src/node/hooks/express/socketio.ts

@@ -70,29 +70,30 @@ exports.expressCreateServer = (hookName:string, args:ArgsExpressType, cb:Functio
   // there shouldn't be a browser that isn't compatible to all
   // transports in this list at once
   // e.g. XHR is disabled in IE by default, so in IE it should use jsonp-polling
-  io = new Server(args.server, {
+  io = new Server({
     transports: settings.socketTransportProtocols,
   })
 
-  function handleConnection() {
-    return (socket: any) => {
-      sockets.add(socket);
-      socketsEvents.emit('updated');
-      // https://socket.io/docs/v3/faq/index.html
-      const session = socket.request.session;
-      session.connections++;
-      session.save();
-      socket.on('disconnect', () => {
-        sockets.delete(socket);
-        socketsEvents.emit('updated');
-      });
-    };
-  }
+  io.attach(args.server, {
+    cookie: false,
+    maxHttpBufferSize: settings.socketIo.maxHttpBufferSize,
+  });
 
-  io.on('connection', handleConnection);
+  io.on('connection', (socket:any) => {
+    sockets.add(socket);
+    socketsEvents.emit('updated');
+    // https://socket.io/docs/v3/faq/index.html
+    const session = socket.request.session;
+    session.connections++;
+    session.save();
+    socket.on('disconnect', () => {
+      sockets.delete(socket);
+      socketsEvents.emit('updated');
+    });
+  });
 
   io.use(exports.socketSessionMiddleware(args));
-
+  
   // Temporary workaround so all clients go through middleware and handle connection
   io.of('/pluginfw/installer').use(exports.socketSessionMiddleware(args))
   io.of('/settings').use(exports.socketSessionMiddleware(args))

src/package.json

@@ -63,7 +63,7 @@
     "security": "1.0.0",
     "semver": "^7.6.0",
     "socket.io": "^3.1.2",
-    "socket.io-client": "^4.7.4",
+    "socket.io-client": "^3.1.2",
     "superagent": "^8.1.2",
     "terser": "^5.28.1",
     "threads": "^1.7.0",
@@ -88,6 +88,7 @@
     "@types/sinon": "^17.0.3",
     "@types/supertest": "^6.0.2",
     "@types/underscore": "^1.11.15",
+    "cypress": "^13.6.4",
     "eslint": "^8.56.0",
     "eslint-config-etherpad": "^3.0.22",
     "etherpad-cli-client": "^3.0.1",
@@ -113,7 +114,7 @@
   },
   "scripts": {
     "lint": "eslint .",
-    "test": "mocha --import=tsx --timeout 120000 --recursive tests/backend/specs/**.ts tests/backend/specs/**/*.ts ../node_modules/ep_*/static/tests/backend/specs",
+    "test": "mocha --import=tsx --timeout 120000 --recursive tests/backend/specs/**.ts tests/backend/specs/**/*.ts",
     "test-container": "mocha --import=tsx --timeout 5000 tests/container/specs/api",
     "dev": "node --import tsx node/server.ts",
     "prod": "node --import tsx node/server.ts",

src/static/js/socketio.js

@@ -19,7 +19,25 @@ const connect = (etherpadBaseUrl, namespace = '/', options = {}) => {
   const baseUrl = new URL(etherpadBaseUrl, window.location);
   const socketioUrl = new URL('socket.io', baseUrl);
   const namespaceUrl = new URL(namespace, new URL('/', baseUrl));
-  return io(namespaceUrl.href, Object.assign({path: socketioUrl.pathname}, options));
+
+  let socketOptions = {
+    path: socketioUrl.pathname,
+    upgrade: true, 
+    transports: ["websocket"]
+  }
+  socketOptions = Object.assign(options, socketOptions);
+  
+  const socket = io(namespaceUrl.href, socketOptions);
+
+  socket.on('connect_error', (error) => {
+    if (socket.io.engine.transports.indexOf('polling') === -1) {
+      console.warn('WebSocket connection failed. Falling back to long-polling.');
+      socket.io.opts.transports = ['polling'];
+      socket.io.engine.upgrade = false;
+    }
+  });
+
+  return socket;
 };
 
 if (typeof exports === 'object') {