WebSocket.IO

WebSocket.IO is an abstraction of the websocket server previously used by Socket.IO. It has the broadest support for websocket protocol/specifications and an API that allows for interoperability with higher-level frameworks such as Engine, Socket.IO's realtime core.

Features

• Fast
• Minimalistic
  • Offers an integration API for higher-level impls to handle authorization, routing, etc
• Widest support of protocols
  • Draft-75
  • Draft-76
  • Draft-00
  • Protocol version 7
  • Protocol version 8
  • Protocol version 13
• Written for Node 0.6

How to use

Server

(A) Listening on a port

var ws = require('websocket.io')
  , server = ws.listen(3000)

server.on('connection', function (socket) {
  socket.on('message', function () { });
  socket.on('close', function () { });
});

(B) Intercepting WebSocket requests for a http.Server

var ws = require('websocket.io')
  , http = require('http').createServer().listen(3000)
  , server = ws.attach(http)

server.on('connection', function (socket) {
  socket.on('message', function () { });
  socket.on('close', function () { });
});

(C) Passing in requests

var ws = require('websocket.io')
  , server = new ws.Server()

server.on('connection', function (socket) {
  socket.send('hi');
});

// …
httpServer.on('upgrade', function (req, socket, head) {
  server.handleUpgrade(req, socket, head);
});

Client-side example

var ws = new WebSocket("ws://host:port/");        

socket.onopen = function() {
 //do something when connection estabilished
};

socket.onmessage = function(message) {
 //do something when message arrives
};

socket.onclose = function() {
 //do something when connection close
};

API

Server

Top-level

These are exposed by require('websocket.io'):

Properties

• version (String): websocket.io version
• protocols (Object): constructors for drafts 75/76/00, protocols 7/8/13.

Methods

• listen
  • Creates an http.Server which listens on the given port and attaches WS to it. It returns 501 Not Implemented for regular http requests.
  • Parameters
    • Number: port to listen on
    • Object: optional options object. See Server for options details.
    • Function: callback for listen
  • Returns Server
• attach
  • Captures upgrade requests for a http.Server. In other words, makes a regular http.Server websocket-compatible.
  • Parameters
    • http.Server: server to attach to.
    • Object: optional, options object. See Server for options details.
  • Returns Server

Server

The main server/manager. Inherits from EventEmitter.

Properties

• clients (Object): table of all connected clients. This property is not set when the Server option clientTracking is false.
• clientsCount (Number): total count of connected clients. This property is not set when the Server option clientTracking is false.

Events

• connection
  • Fired when a new connection is established.
  • Arguments
    • Socket: a Socket object

Methods

• constructor
  • Initializes the server
  • Options
    • path (String): if set, server only listens to request for this path
    • clientTracking (Boolean): enables client tracking. The Server#clients property only is available when this is true (true)
• handleUpgrade

Socket

A representation of a client. Inherits from EventEmitter.

Properties

• req (http.ServerRequest): Request that originated the connection.
• socket (net.Socket): Stream that originated the connection.
• readyState (String): opening, open, closed.
• name (String): websocket-hixie, websocket.
• protocolVersion (String): hixie-75, hixie-76 and hybi.

Events

• close
  • Fired when the connection is closed.
• message/data
  • Fired when data is received
  • Arguments
    • String: utf-8 string
• error
  • Fired when an error occurs.
  • Arguments
    • Error: error object

Methods

• send / write
  • Sends a message.
  • Parameters
    • String: utf-8 string with outgoing data
  • Returns Socket for chaining
• close / end
  • Closes the socket
  • Returns Socket for chaining
• destroy
  • Forcibly closes the socket.

Support

The support channels for websocket.io are the same as socket.io:

• irc.freenode.net #socket.io
• Google Groups
• Website

Development

To contribute patches, run tests or benchmarks, make sure to clone the repository:

git clone git://github.com/LearnBoost/websocket.io.git

Then:

cd websocket.io
npm install

Tests

$ make test

Credits

WebSocket.IO is possible thanks to the contributions by:

• Einar Otto Stangvik [[email protected]]
• Arnout Kazemier [[email protected]]
• Nico Kaiser [[email protected]]

License

(The MIT License)

Copyright (c) 2011 Guillermo Rauch <[email protected]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.