Lightweight WebSockets for Node.js

node-lws is a libwebsockets wrapper for Node.js and C++. It implements an interface similar to the one available in ws.

By using the ridiculously lightweight libwebsockets as a foundation, node-lws significantly outperforms ws in both memory usage and cpu time. Since ws is self entitled "fastest" and "blazingly fast", node-lws can only be described as "fastester" and "blazinglier fast".

NOTE: This project is still very young and has some missing major features. Keep calm and wait for things to fall into place.

ALSO NOTE: Builds are not up-to-date and things can be completely broken at times. I'm working on it.

Overview

Consider main.js:

var lws = require('lws');
var server = new lws.Server(3000);

server.on('connection', function (socket) {
    console.log('[Connection]');
    server.send(socket, 'some message');
    server.send(socket, 'some other message');
    server.send(socket, 'some third message');
    server.setUserData(socket, 'this is private');
});

server.on('message', function (socket, message) {
    console.log('[Message: ' + message + ']');
    server.send(socket, 'two can playeth that game!');
});

server.on('close', function (socket) {
    console.log('[Close]');
    console.log(server.getUserData(socket));
});

console.log('Running server on port 3000');

Installing

npm install lws is your friend.

• Node 4.x support (ABI 46)
• Linux & Mac OS X 10.7+

Manual compilation

If the pre-compiled binaries don't suffice, you could compile the wrapper manually. It should compile for Node 0.12+. Start by cloning, configuring, compiling and installing libwebsockets:

git clone https://github.com/warmcat/libwebsockets.git
cd libwebsockets
cmake -DLWS_WITH_LIBEV=1 -DCMAKE_C_FLAGS=-fPIC -DCMAKE_INSTALL_PREFIX:PATH=/usr .
make
sudo make install

node-lws can then be compiled in a pretty straight forward way.

Documentation

The interface is expanding as we go (and will be re-designed in the future). Every functionality is currently implemented in the Server object:

• Server(port) constructs and returns a Server object
• Server.send(socket, "some string") enqueues a string for sending (needs work to reduce copying, Buffer support etc)
• Server.on('connect', function(socket)) registers an event handler for connections
• Server.on('message', function(socket, message)) registers an event handler for messages
• Server.on('close', function(socket)) registers an event handler for disconnections
• Server.setUserData(socket, value) sets the user data for this socket
• Server.getUserData(socket) returns the set user data for this socket
• Server.broadcast("some shared string") enqueues a string for sending on all open connections [not implemented yet]