Lightweight WebSockets for Node.js

node-lws (or simply lws) is a libwebsockets wrapper for Node.js and C++. It exposes an easy to use interface much like the one available in ws. In contrast to ws, node-lws is very lightweight and scales to millions of connections where ws simply chokes due to excessive memory usage.

• node-lws uses less than 40% the memory per connection compared to ws.
• node-lws establishes connections in less than 10% the time compared to ws.
• node-lws echoes messages in less than 30% the time compared to ws.

Installation

npm install --save lws

• Node 4.x, 5.x support (ABI 46-47).
• Linux & Mac OS X 10.7+

NOTE: This project started Jan 13, 2016. Please use the issue tracker to report bugs, feature requests and other opinions.

Overview

var lws = require('lws');  var server = new lws.Server({ port: 3000 });    server.on('connection', function (socket) {      console.log('[Connection]');      server.send(socket, new Buffer('a text message'), false);      server.send(socket, new Buffer('a binary message'), true);      server.setUserData(socket, 'persistent per socket data');  });    server.on('message', function (socket, message, binary) {      console.log('[Message: ' + message + ']');      server.send(socket, new Buffer('You sent me this: \"' + message + '\"'), false);  });    server.on('close', function (socket) {      console.log('[Close]');      console.log(server.getUserData(socket));  });    console.log('Running server on port 3000');

Class: lws.Server

new lws.Server(options)

Constructs a new Server object. options is an object with these fields:

• port : Integer
• path : String
• keepAliveTime : Integer
• keepAliveInterval : Integer
• keepAliveRetry : Integer

Event: 'connection'

function (socket) { }

Emitted when a connection has been established. socket is a copy of the internal socket structure. Changes made to this copy does not persist - use setUserData to set persistent data on a socket.

Event: 'message'

function (socket, message, binary) { }

Emitted when a message has been received. message is a Node.js Buffer. This buffer is only valid inside this callback. When this callback goes out of scope, the internal memory will be invalidated. You need to make a deep copy of the message if you want to keep it for later.

Event: 'close'

function (socket) { }

Emitted when a connection has been closed. Data set with setUserData is valid until this callback goes out of scope.

setUserData(socket, data)

server.setUserData(socket, 'string');

Used to set persistent private data on socket. Currently the type is string, meaning you can store objects as JSON.

getUserData(socket)

server.getUserData(socket);

Returns the private persistent data set on socket.

send(socket, message, binary)

server.send(socket, buffer, false);

Queue a Node.js Buffer for sending. This function call makes at least one internal memory allocation and one memory copy. message is sent as binary if the (boolean) binary flag is true.

项目地址： https://github.com/alexhultman/node-lws