websocket

WebSocket Client & Server Implementation for Node
=================================================




Overview
--------
This is a (mostly) pure JavaScript implementation of the WebSocket protocol versions 8 and 13 for Node. There are some example client and server applications that implement various interoperability testing protocols in the "test/scripts" folder.

Documentation
=============

You can read the full API documentation in the docs folder.

Changelog
---------

Current Version: 1.0.35 - Release 2024-05-12

* Updated from vulnerable version of es5-ext to a newer version that has been patched. Thanks, @Tringapps-Dharshan

View the full changelog

Browser Support
---------------

All current browsers are fully* supported.

* Firefox 7-9 (Old) (Protocol Version 8)
* Firefox 10+ (Protocol Version 13)
* Chrome 14,15 (Old) (Protocol Version 8)
* Chrome 16+ (Protocol Version 13)
* Internet Explorer 10+ (Protocol Version 13)
* Safari 6+ (Protocol Version 13)

(Not all W3C WebSocket features are supported by browsers. More info in the Full API documentation)

Benchmarks
----------
There are some basic benchmarking sections in the Autobahn test suite. I've put up a benchmark page that shows the results from the Autobahn tests run against AutobahnServer 0.4.10, WebSocket-Node 1.0.2, WebSocket-Node 1.0.4, and ws 0.3.4.

(These benchmarks are quite a bit outdated at this point, so take them with a grain of salt. Anyone up for running new benchmarks? I'll link to your report.)

Autobahn Tests
--------------
The very complete Autobahn Test Suite is used by most WebSocket implementations to test spec compliance and interoperability.

- View Server Test Results

Installation
------------

In your project root:

$ npm install websocket

Then in your code:

``javascript
var WebSocketServer = require('websocket').server;
var WebSocketClient = require('websocket').client;
var WebSocketFrame = require('websocket').frame;
var WebSocketRouter = require('websocket').router;
var W3CWebSocket = require('websocket').w3cwebsocket;
`

Current Features:
-----------------
- Licensed under the Apache License, Version 2.0
- Protocol version "8" and "13" (Draft-08 through the final RFC) framing and handshake
- Can handle/aggregate received fragmented messages
- Can fragment outgoing messages
- Router to mount multiple applications to various path and protocol combinations
- TLS supported for outbound connections via WebSocketClient
- TLS supported for server connections (use https.createServer instead of http.createServer)
- Thanks to pors for confirming this!
- Cookie setting and parsing
- Tunable settings
- Max Receivable Frame Size
- Max Aggregate ReceivedMessage Size
- Whether to fragment outgoing messages
- Fragmentation chunk size for outgoing messages
- Whether to automatically send ping frames for the purposes of keepalive
- Keep-alive ping interval
- Whether or not to automatically assemble received fragments (allows application to handle individual fragments directly)
- How long to wait after sending a close frame for acknowledgment before closing the socket.
- W3C WebSocket API for applications running on both Node and browsers (via the W3CWebSocket class).


Known Issues/Missing Features:
------------------------------
- No API for user-provided protocol extensions.


Usage Examples
==============

Server Example
--------------

Here's a short example showing a server that echos back anything sent to it, whether utf-8 or binary.

`javascript
#!/usr/bin/env node
var WebSocketServer = require('websocket').server;
var http = require('http');

var server = http.createServer(function(request, response) {
console.log((new Date()) + ' Received request for ' + request.url);
response.writeHead(404);
response.end();
});
server.listen(8080, function() {
console.log((new Date()) + ' Server is listening on port 8080');
});

wsServer = new WebSocketServer({
httpServer: server,
// You should not use autoAcceptConnections for production
// applications, as it defeats all standard cross-origin protection
// facilities built into the protocol and the browser. You should
// always verify the connection's origin and decide whether or not
// to accept it.
autoAcceptConnections: false
});

function originIsAllowed(origin) {
// put logic here to detect whether the specified origin is allowed.
return true;
}

wsServer.on('request', function(request) {
if (!originIsAllowed(request.origin)) {
// Make sure we only accept requests from an allowed origin
request.reject();
console.log((new Date()) + ' Connection from origin ' + request.origin + ' rejected.');
return;
}

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.sendUTF(message.utf8Data);
}
else if (message.type === 'binary') {
console.log('Received Binary Message of ' + message.binaryData.length + ' bytes');
connection.sendBytes(message.binaryData);
}
});
connection.on('close', function(reasonCode, description) {
console.log((new Date()) + ' Peer ' + connection.remoteAddress + ' disconnected.');
});
});
`

Client Example
--------------

This is a simple example client that will print out any utf-8 messages it receives on the console, and periodically sends a random number.

This code demonstrates a client in Node.js, not in the browser

`javascript
#!/usr/bin/env node
var WebSocketClient = require('websocket').client;

var client = new WebSocketClient();

client.on('connectFailed', function(error) {
console.log('Connect Error: ' + error.toString());
});

client.on('connect', function(connection) {
console.log('WebSocket Client Connected');
connection.on('error', function(error) {
console.log("Connection Error: " + error.toString());
});
connection.on('close', function() {
console.log('echo-protocol Connection Closed');
});
connection.on('message', function(message) {
if (message.type === 'utf8') {
console.log("Received: '" + message.utf8Data + "'");
}
});

function sendNumber() {
if (connection.connected) {
var number = Math.round(Math.random() * 0xFFFFFF);
connection.sendUTF(number.toString());
setTimeout(sendNumber, 1000);
}
}
sendNumber();
});

client.connect('ws://localhost:8080/', 'echo-protocol');
`

Client Example using the W3C WebSocket API
--------------------------------------------

Same example as above but using the W3C WebSocket API.

`javascript
var W3CWebSocket = require('websocket').w3cwebsocket;

var client = new W3CWebSocket('ws://localhost:8080/', 'echo-protocol');

client.onerror = function() {
console.log('Connection Error');
};

client.onopen = function() {
console.log('WebSocket Client Connected');

function sendNumber() {
if (client.readyState === client.OPEN) {
var number = Math.round(Math.random() * 0xFFFFFF);
client.send(number.toString());
setTimeout(sendNumber, 1000);
}
}
sendNumber();
};

client.onclose = function() {
console.log('echo-protocol Client Closed');
};

client.onmessage = function(e) {
if (typeof e.data === 'string') {
console.log("Received: '" + e.data + "'");
}
};
`

Request Router Example
----------------------

For an example of using the request router, see libwebsockets-test-server.js in the test` folder.

Resources
---------

A presentation on the state of the WebSockets protocol that I gave on July 23, 2011 at the LA Hacker News meetup. WebSockets: The Real-Time Web, Delivered