PhantomJS snippet that lists (and counts) all domains that are being accessed during a request

resources.js

var page = require('webpage').create();

function extractDomain(url) {
    var domain = (url.indexOf("://") > -1) ? url.split('/')[2] : url.split('/')[0];
    domain = domain.split(':')[0];
    return domain;
}

var domains = {};

page.onResourceRequested = function(requestData, networkRequest) {
	var domain = extractDomain(requestData.url);
	if (domains.hasOwnProperty(domain)) {
		domains[domain]++;
	} else {
		domains[domain]=1;
	}
};
page.open('http://magento.com', function() {
	for (var domain in domains) {
		console.log(domain, domains[domain]);
	}
	phantom.exit();
});