Q example

gistfile1.js

var Q = require('Q');
var mongo = require('mongodb').MongoClient;
 
var main = function(){
    connect('mongodb://localhost')
    .then(close)
    .catch(logError);
};

function connect(url) {
    return Q.nfncall(mongo.connect, url);
}

function close(db) {
    return Q.nfncall(db.close)
            .then(function () {
                console.log('Finished!');
            });
}

function logError(error){
    console.dir(error);
}

main();