simple-todo/app.js

var express = require('express');
var app = express();
var mongoose = require('mongoose');
var config = require('./config');
var port = process.env.TODO_APP_PORT || 3001;
var test = 'mongodb://' + process.env.MONGO_USER + ':' + process.env.MONGO_PASWORD + '@127.0.0.1:27017/todo'

app.use('assets', express.static(__dirname + '/public'));

app.set('view engine', 'ejs');

var promise = mongoose.createConnection(test, {
  useMongoClient: true,
  /* other options */
});

promise.then(function(db) {
  /* Use `db`, for instance `db.model()`*/
  console.log(db);
});

app.listen(port);