Separating file server and socket.io logic in node.js

Question

I\'m fairly new to node.js and I\'ve found its quite complicated separating a project into multiple files as the project grows in size. I had one large file before which ser

Answer 1

i would do something like this.

app.js

var app = require('http').createServer(handler),
    sockets = require('./sockets'),
    fs = require('fs');

function handler (req, res) {
  fs.readFile(__dirname + '/index.html',
  function (err, data) {
    if (err) {
      res.writeHead(500);
      return res.end('Error loading index.html');
    }

    res.writeHead(200);
    res.end(data);
  });
}

sockets.startSocketServer(app);
app.listen(80);

and sockets.js

var socketio = require('socket.io'),
        io, clients = {};

module.exports = {

        startSocketServer: function (app) {
                io = socketio.listen(app);

                // configure
                io.configure('development', function () {
                        //io.set('transports', ['websocket', 'xhr-polling']);
                        //io.enable('log');
                });

                io.configure('production', function () {
                        io.enable('browser client minification');  // send minified client
                        io.enable('browser client etag');          // apply etag caching logic based on version number
                        io.set('log level', 1);                    // reduce logging
                        io.set('transports', [                     // enable all transports (optional if you want flashsocket)
                            'websocket'
                          , 'flashsocket'
                          , 'htmlfile'
                          , 'xhr-polling'
                          , 'jsonp-polling'
                        ]);
                });
                //

                io.sockets.on('connection', function (socket) {
                        console.log("new connection: " + socket.id);

                        socket.on('disconnect', function () {
                                console.log("device disconnected");

                        });

                        socket.on('connect_device', function (data, fn) {
                                console.log("data from connected device: " + data);
                                for (var col in data) {
                                        console.log(col + " => " + data[col]);
                                }


                        });
                });
        }
};

i just copy&pasted some of my old code - don't really know what changed in the last versions of socket.io, but this is more about the structure than the actual code.

and i would only use 2 files for your purposes, not 3. when you think about splitting it up further, maybe one other file for different routes ...

hope this helps.

Answer 2

I have had a crack at this as well and I am fairly happy with the result. Check out https://github.com/hackify/hackify-server for source code.

Answer 3

I've another solution. You can use require.js creating a module and pass "app" as an argument. Within the module you can start socket.io and organize your sockets.

app.js:

  var requirejs = require('requirejs');

  requirejs.config({
      baseUrl: './',
      nodeRequire: require
  });

  requirejs(['sockets'], function(sockets) {

    var app = require('http').createServer()
      , fs  = require('fs')
      , io  = sockets(app);

      // do something
      // add more sockets here using "io" resource

  });

In your socket.js module you can do something like this:

  define(['socket.io'], function(socket){
    return function(app){
      var server = app.listen(3000) 
        , io     = socket.listen(server);

      io.sockets.on('connection', function (socket) {
        console.log('connected to socket');

        socket.emit('news', { hello: 'world' });
        socket.on('my other event', function (data) {
          console.log(data);
        });

        // more more more

      });

      return io;
    }
  });

I hope help you with my contribution.

Answer 4

In socket.io 0.8, you should attach events using io.sockets.on('...'), unless you're using namespaces, you seem to be missing the sockets part:

io.listen(fileserver).sockets.on('connection', handler)

It's probably better to avoid chaining it that way (you might want to use the io object later). The way I'm doing this right now:

// sockets.js
var socketio = require('socket.io')

module.exports.listen = function(app){
    io = socketio.listen(app)

    users = io.of('/users')
    users.on('connection', function(socket){
        socket.on ...
    })

    return io
}

Then after creating the server app:

// main.js
var io = require('./lib/sockets').listen(app)