中継サーバに Redis Pub/Sub を使う

chat.js

// This program is free software. It comes without any warranty, to
// the extent permitted by applicable law. You can redistribute it
// and/or modify it under the terms of the Do What The Fuck You Want
// To Public License, Version 2, as published by Sam Hocevar. See
// http://sam.zoy.org/wtfpl/COPYING for more details.

var sys        = require('sys')
  , opts       = require('opts')
  , ws         = require('websocket-server')
  , redis      = require('redis')
  , server     = ws.createServer()
  , subscriber = redis.createClient(6379, 'localhost')
  , publisher  = redis.createClient(6379, 'localhost');

opts.parse([
    {
        'short':       'p',
        'long':        'port',
        'description': 'WebSocket Port',
        'value':       true,
        'required':    true
    }
]);

subscriber.on("error", function(err) {
    sys.debug(err);
});

publisher.on("error", function(err) {
    sys.debug(err);
});

subscriber.subscribe("chat");
subscriber.on("message", function(channel, message) {
    sys.puts(message);
    server.broadcast(message);
});

server.addListener("connection", function(connection) {
    sys.puts("client connected: " + connection.id);

    connection.addListener("message", function(message) {
        publisher.publish("chat", message);
    });
});

server.addListener("close", function(connection) {
    sys.puts("client disconnected: " + connection.id);
});

server.listen(opts.get('port'));