onmessage event in websocket client is not getting fired

html, javascript, node.js, websocket

Solution

These lines are responsible for your problem:

connection.onopen = html5WebSocketClient.onOpen(event);
connection.onmessage = html5WebSocketClient.onMessage(event);
connection.onclose = html5WebSocketClient.onClose(event); 
connection.onerror = html5WebSocketClient.onError(event);

Let's analyze this. `html5WebSocketClient.onOpen(event);` calls `onOpen` with argument `event` (which is `undefined`) and returns `undefined` (`onOpen` does not return anything). Thus `connection.onopen` becomes `unedefined`. But `connection.onopen` is supposed to be a function. So instead of calling these functions simply do this:

connection.onopen = html5WebSocketClient.onOpen;
connection.onmessage = html5WebSocketClient.onMessage;
connection.onclose = html5WebSocketClient.onClose; 
connection.onerror = html5WebSocketClient.onError;

Problem

I am using node.js to implement websocket server and client. The handshake between them looks like this. Request URL: ws://localhost:8015/ Request Method: GET Status Code: 101 Switching Protocols Request Headers ``` Cache-Control: no-cache Connection: Upgrade Cookie: SQLiteManager_currentLangue=2 Host: localhost:8015 Origin: http:/localhost:8080 Pragma: no-cache Sec-WebSocket-Extensions: x-webkit-deflate-frame Sec-WebSocket-Key: A/knWtXFtTa5V6po8XOfjg== Sec-WebSocket-Protocol: echo-protocol Sec-WebSocket-Version: 13 Upgrade: websocket User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.116 Safari/537.36 ``` Response Headers ``` Connection: Upgrade Origin: http:/localhost:8080 Sec-WebSocket-Accept: 5OUv+g5mBPxVDug4etJfGX4lxIo= Sec-WebSocket-Protocol: echo-protocol Upgrade: websocket ``` The server is getting the message sent from client (I am logging the message on console), however onmessage event in client is not getting fired when server sends the message. The other thing confusing me is as soon as connection is opened, onmessage event in clients gets fired only once. Please help...I am trying to echo the message on the server back to client. EDIT: This is how I am handling events in websocket client... ``` html5WebSocketClient.connect = function(){ if(window.WebSocket != undefined){ if(connection.readyState == undefined || connection.readyState > 1) connection = new WebSocket('ws://localhost:8015/','echo-protocol'); } if (window.MozWebSocket) { window.WebSocket = window.MozWebSocket; } connection.onopen = html5WebSocketClient.onOpen(event); connection.onmessage = html5WebSocketClient.onMessage(event); connection.onclose = html5WebSocketClient.onClose(event); connection.onerror = html5WebSocketClient.onError(event); ``` }; ``` html5WebSocketClient.onOpen = function(event) { $('#some_label').text("Connected"); }; html5WebSocketClient.onClose = function(event) { $('#some_label').text("Disconnected"); }; html5WebSocketClient.onError = function(event) { $('#some_label').text("Error"); }; //This is only getting fired when connection opens html5WebSocketClient.onMessage = function(message) { if(message.data != undefined) { alert($.parseJSON(message.data)); } }; //Server is getting this message html5WebSocketClient.sendMessage = function() { var message = {"name": value, "name": value}; connection.send(JSON.stringify(message)); }; ``` And here's how I had implemented server.. ``` var http = require('http'); var WebSocketServer = require('websocket').server; var server = http.createServer(function (req, res) { res.writeHead(200, {'Content-Type': 'text/plain'}); res.end('Hello Node.js From HTML5\n'); }).listen(8015, "127.0.0.1"); wsServer = new WebSocketServer({ httpServer: server, autoAcceptConnections: false }); wsServer.on('request', function(request) { var connection = request.accept('echo-protocol', request.origin); console.log((new Date()) + ' Connection accepted.'); connection.on('message', function(message) { if (message.type === 'utf8') { console.log('Received Message: ' + message.utf8Data); connection.send(message.utf8Data); //Client is not getting this message..? } }); connection.on('close', function(reasonCode, description) { console.log((new Date()) + ' Peer ' + connection.remoteAddress + ' disconnected.'); }); }); ```

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