server

gistfile1.js

var express = require('express');
var io      = require('socket.io');
var redis   = require("redis");
var url     = require("url");

var server  = express.createServer();
var port    = process.env.PORT || 3000;

server.configure(function() {
  server.set('view engine', 'html');
  server.set('views', __dirname + '/views');
  server.set('view options', {layout: false});
  server.register('.html', {
    compile: function(str, options){
      return function(locals){
        return str;
      };
    }
  });
  server.use(express.static(__dirname + '/public'));
});

// routes
server.get('/', function(req, res) {
  res.render('index');
});

server.listen(port);

/*    REDIS SHIT    */
if (process.env.REDISTOGO_URL) {
  var rtg         = url.parse(process.env.REDISTOGO_URL);
  var redisClient = redis.createClient(rtg.port, rtg.hostname);

  redisClient.auth(rtg.auth.split(":")[1]);
} else {
  var redisClient = redis.createClient();
}

redisClient.on("connect", function () {
  redisClient.flushall(); // This eventually needs to be removed, if the server goes idle and starts back up it flushes the redis data store
});

redisClient.on("error", function (err) {
  console.log("Error " + err);
});

/*    SOCKET.IO SHIT    */
var io = io.listen(server);

// heroku said to do this socket.io config shit so I did it, not sure what it does
io.configure(function () { 
  io.set('transports', ['xhr-polling']); 
  io.set('polling duration', 10); 
});

// handler for when a new client connects
io.sockets.on('connection', function (client) {
  // setup new clients stuff
  var clientId = client['id'];
  
  // add the new client to the 'clients' set in redis
  // one day this will check to see if the client that connected is already a client 
  // and basically just "sign them in" and mark them connected
  redisClient.sadd("clients", "client:"+clientId);
  redisClient.hmset("client:"+clientId, "clientId", clientId, "status", "connected", "x", 0, "y", 0);

  // get the list of currently connected clients and also let already connected 
  // clients know about the new user
  redisClient.smembers("clients", function (err, clients) {
    console.log(clients);
    var initClientList = {};
    var clientCount = 0;
                    
    for (var thisClientId in clients) {
      redisClient.hgetall(clients[thisClientId], function (err, clientData) {
        if (clientData["status"] == "connected") {
          initClientList[clientData["clientId"]] = [parseInt(clientData["x"]), parseInt(clientData["y"])];
        }
        
        clientCount++
        
        // we only need to send our messages when all the currently connected clients are added to the 'initClientList'
        if (clientCount == clients.length) {
          // send the init action to get the newly connected client started
          client.emit('init', { clientId: clientId, initClientList: initClientList });  
          // let the already connected clients know about the newly connected client
          client.broadcast.emit('clientConnected', { clientId: clientId, x: 0, y: 0 }); 
          // we dont need this anymore after its been sent
          initClientList = null; 
        }
      });
    }
  });
  
  // clients requesting to move
  client.on('requestToMoveClient', function (data) {
    var direction = data.direction;
    
    redisClient.hgetall("client:"+clientId, function (err, client) {
      var x = parseInt(client["x"]);
      var y = parseInt(client["y"]);
      
      if      (direction == "left"  && x-100 >= 0)    redisClient.hincrby("client:"+clientId, "x", -100,  function() { clientMoved(); });
      else if (direction == "right" && x+100 <= 4000) redisClient.hincrby("client:"+clientId, "x", 100,   function() { clientMoved(); });
      else if (direction == "up"    && y-100 >= 0)    redisClient.hincrby("client:"+clientId, "y", -100,  function() { clientMoved(); });
      else if (direction == "down"  && y+100 <= 3000) redisClient.hincrby("client:"+clientId, "y", 100,   function() { clientMoved(); });
    });
    
    function clientMoved () {
      client.broadcast.emit('clientMoved', { clientId: clientId, direction: direction });
      client.emit('clientMoved', { clientId: clientId, direction: direction });
    }
  });
  
  // client disconnected
  client.on('disconnect', function () {
    redisClient.hset("client:"+clientId, "status", "disconnected");
    client.broadcast.emit('clientDisconnected', { clientId: clientId });
  });
});