не удаётся получить src из iframe

есть код:

<div class="product-reviews" id="feedback"><iframe class="product-evaluation" id="product-evaluation" scrolling="no" frameborder="0" marginwidth="0" marginheight="0" width="100%" height="1723" src="//feedback.aliexpress.com/display/productEvaluation.htm?v=2&amp;productId=32795043900&amp;ownerMemberId=221376560&amp;companyId=231305801&amp;memberType=seller&amp;startValidDate=&amp;i18n=true"></iframe></div>

необходимо получить src пробовал так:

var feedbackSrc = $('#feedback > iframe', dom)
    .attr('src');

и так:

 var feedbackSrc = $('product-evaluation', dom)
    .attr('src');

feedbackSrc всегда выходит undefined

downloadHtml("https://aliexpress.com/item/item/" + meta.productId + ".html", function(dom) {
console.log('meta.productId: https://aliexpress.com/item/item/' + meta.productId + '.html');
//var feedbackSrc = $('#product-evaluation').attr('src');
 var feedbackSrc = $('#feedback > iframe')
    .attr('src');
    console.log('feedbackSrc:' + feedbackSrc);
       // Download first feedback page
downloadPhotos({
    'pageNumber': 1,
    'feedbackSrc': feedbackSrc
}, function(err, firstPageFeedbacks, pageCount) {
    if (!pageCount || pageCount < 2) {
        var package = {
            feedbacks: firstPageFeedbacks,
            productId: meta.productId,
            categoryId: meta.categoryId
        };
        sendFeedbacks(package, function() {
            openPhotos();
        });
    }
    var parseTasks = range(2, pageCount + 1)
        .map(function(pageNumber) {
            return {
                'pageNumber': pageNumber,
                'feedbackSrc': feedbackSrc
            };
        });
    // Download other feedback pages in parallel
    async.map(parseTasks, downloadPhotos, function(err, feedbacks) {
        if (err) {
            alert('Feedback pages downloading error, try again :(');
        } else {
            feedbacks.unshift(firstPageFeedbacks);
            // flatten pages array
            var flatFeedbacks = [].concat.apply([], feedbacks);
            var package = {
                feedbacks: flatFeedbacks,
                productId: meta.productId,
                categoryId: meta.categoryId
            };
            console.log(package);
            console.log('settings.feedbackSrc2:' + settings.feedbackSrc);
            sendFeedbacks(package, function() {
                openPhotos();
            });
        }
    });
});

});