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I'm working on my first node project, I basically followed the thinkster post to get me started. I've managed to build a simple app and now I'm trying to configure socket.io.

The socket.io initialization code and event handlers are not hard to understand, what is really confusing me is how should I organize that code between the bin/www and the app.js files. Both files were generated automatically by express. bin/www depends on the app.js module, the first initiates the server variable which is needed to start up the socket module, so that means I should put all the 'socket.io' code in the bin/www file?

I don't think I should be touching that file though, I would be more comfortable putting that code into app.js or even inside a dedicated file. I think I need to pass the server object reference between modules, but I'm not sure how to do that.

This is the content of the bin/www file:

#!/usr/bin/env node

/**
 * Module dependencies.
 */

var app = require('../app');
var debug = require('debug')('oculus:server');
var http = require('http');

/**
 * Get port from environment and store in Express.
 */

var port = normalizePort(process.env.PORT || '3000');
app.set('port', port);

/**
 * Create HTTP server.
 */

var server = http.createServer(app);

/**
 * Listen on provided port, on all network interfaces.
 */

server.listen(port);
server.on('error', onError);
server.on('listening', onListening);

/**
 * Normalize a port into a number, string, or false.
 */

function normalizePort(val) {
    var port = parseInt(val, 10);

    if (isNaN(port)) {
        // named pipe
        return val;
    }

    if (port >= 0) {
        // port number
        return port;
    }

    return false;
}

/**
 * Event listener for HTTP server "error" event.
 */

function onError(error) {
    if (error.syscall !== 'listen') {
        throw error;
    }

    var bind = typeof port === 'string' ? 'Pipe ' + port : 'Port ' + port

    // handle specific listen errors with friendly messages
    switch (error.code) {
        case 'EACCES':
            console.error(bind + ' requires elevated privileges');
            process.exit(1);
            break;
        case 'EADDRINUSE':
            console.error(bind + ' is already in use');
            process.exit(1);
            break;
        default:
            throw error;
    }
}

/**
 * Event listener for HTTP server "listening" event.
 */

function onListening() {
    var addr = server.address();
    var bind = typeof addr === 'string' ? 'pipe ' + addr : 'port ' + addr.port;
    debug('Listening on ' + bind);
}

And this the content of the app.js file:

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var mongoose = require('mongoose');

// Mongoose
require('./models/Aplicacoes');
mongoose.connect('mongodb://localhost/oculus');

var routes = require('./routes/index');
var users = require('./routes/users');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

// uncomment after placing your favicon in /public
//app.use(favicon(__dirname + '/public/favicon.ico'));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
    extended: false
}));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', routes);
app.use('/users', users);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
    var err = new Error('Not Found');
    err.status = 404;
    next(err);
});

// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
    app.use(function(err, req, res, next) {
        res.status(err.status || 500);
        res.render('error', {
            message: err.message,
            error: err
        });
    });
}

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
        message: err.message,
        error: {}
    });
});

/**
 * Some business code here
 */
....

module.exports = app;

this is my project structure

felipe_gdr
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2 Answers2

3

First, let me tell you, what you're trying to do is kinda right. Not to mess with the bin/www would be fine.

But remember express generator is just that. A generator for you to build upon. You generate, and the apply your own modifications.

My choice would be to:

  • copy bin/www to a new bin/wwwio,
  • Update the bin/wwwio script to attach socket.io to the created http server.
  • Update bin/wwwio to require() a new file ../io.js that handles all my socket.io events.
  • Modifiy package.json to run node ./bin/wwwio on npm start instead of bin/www

You can also look at the answers on this other question about the some topic:

Using socket.io in Express 4 and express-generator's /bin/www

You'll find several approaches to achieving modularity with little touching on the bin/www script.

Community
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Osk
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0

Try following these simple steps

Install Socket.io with the following command:

npm install --save socket.io

Add the following to app.js:

var sockIO = require('socket.io')(); app.sockIO = sockIO;

In bin/www,

after var server = http.createServer(app), add the following:

var sockIO = app.sockIO; sockIO.listen(server);

To test functionality, in app.js, you can add the line:

sockIO.on('connection', function(socket){ console.log('A client connection occurred!'); });

Now in layout.hbs add the following snippet before the body closing tag < /body >:

<script src="/socket.io/socket.io.js"></script> <script> var socket = io(); </script>

Further, I have created the GIT REPOSITORY for the complete working project of chat with Sockets express generator.

https://github.com/Mohsin05/Sockets-Express-Generator

I hope it will help everyone. ;)

Mohsin Younas
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