bartolo.js

var express = require('express');
var fs = require('fs');
var handlebars = require('handlebars');


var source = new Buffer(10);
// El objeto source no contiene nada
console.log(source.toString('utf-8'));

fs.readFile('home.html', function(error, content){
  if(error) {
    console.log(error);
  } else {
    //Asignar a source los contenidos leidos
    source = content;
  }
});

var app = express();

app.get('/', function (req, res) {
  // El objeto source ahora sí tendra el contenido
  res.send(source.toString('utf-8'));
});

var server = app.listen(3000, function () {
  var host = server.address().address;
  var port = server.address().port;

  console.log('Backend listo para combatir en http://%s:%s', host, port);
});