server.js

#!/usr/bin/env node

/**
 * Loading configuration from our .env file.
 */
require('dotenv').config();

process.env.SPARK_RELEASE_URL = process.env.SPARK_RELEASE_URL || 'https://github.com/Midburn/spark/releases';

/**
 * Module dependencies.
 */
var app = require('./app');
var debug = require('debug')('spark:server');
var http = require('http');
var log = require('./libs/logger.js')(module);

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

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

/**
 * Create HTTP server.
 */

var server = http.createServer(app);

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

server.listen(port, function() {
    log.info('Listening on port ' + port + " (http://"+ host +":" + 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':
            log.error(bind + ' requires elevated privileges');
            process.exit(1);
            break;
        case 'EADDRINUSE':
            log.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);
}