RandomEtc

var url = require('url'),
    mongodb = require('mongodb');

var sourceUrl = 'mongodb://user:pass@host:port/db',
    targetUrl = 'mongodb://user:pass@host:port/db',
    collectionName = 'my_awesome_collection';

function openDbFromUrl(mongoUrl, cb) {
    var dbUrl = url.parse(mongoUrl),
        dbName = dbUrl.pathname.slice(1), // no slash