What's the difference? Why can't JavaScript work with both responses?

Question

I am working on a RSS-reader using as much Javascript as possible. Because of the same-origin-policy I have to request the XML files of the feeds with another solution. First I used the Yahoo! Query Language (YQL) but to be independent I tried to write some PHP code. Although the responses of both solutions are almost the same (with YQL there is some Yahoo data) my solution using PHP does not work.

The YQL solution

function yahoo() {
// request the xml
$.get("https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20xml%20where%20url%3D'http%3A%2F%2Fnews.yahoo.com%2Frss%2Ftopstories'&diagnostics=false", function (data) {
// save the data (title, content, link, date) to the localStorage
    $(data).find("item").each(function () {
        el = $(this);
        if (!el.find("title").text() || !el.find("description").text() || !el.find("link").text() || !el.find("pubDate").text()) {
            console.log("errorEntry");
        } else {
            localStorage.setItem('titleEntry' , el.find("title").text());
            localStorage.setItem('contentEntry' , el.find("description").text());
            localStorage.setItem('linkEntry' , el.find("link").text());
            localStorage.setItem('dateEntry' , el.find("pubDate").text());
    }
    });
});
}

My solution JavaScript:

function php() {
// request the xml
$.get("rss_request.php?feedUrl=http://news.yahoo.com/rss/topstories", function (data) {
// save the data (title, content, link, date) to the localStorage
    $(data).find("item").each(function () {
        el = $(this);
        if (!el.find("title").text() || !el.find("description").text() || !el.find("link").text() || !el.find("pubDate").text()) {
            console.log("errorEntry");
        } else {
            localStorage.setItem('titleEntry' , el.find("title").text());
            localStorage.setItem('contentEntry' , el.find("description").text());
            localStorage.setItem('linkEntry' , el.find("link").text());
            localStorage.setItem('dateEntry' , el.find("pubDate").text());
            localStorage.setItem('typeEntry' , "rss");
    }
    });
});
}

PHP (rss_request.php):

<?php
    $url = $_GET["feedUrl"];
    $response = file_get_contents ($url);
    echo $response;
?> 

Answer 1

What's the difference? Why can't JavaScript work with both responses?

Let's apply some simple logic here which is useful when you look for causes.

You ask about differences. You give two code examples. The difference in those two code examples is:

A: $.get("https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20xml%20where%20url%3D'http%3A%2F%2Fnews.yahoo.com%2Frss%2Ftopstories'&diagnostics=false", function (data) {

---

B: $.get("rss_request.php?feedUrl=http://news.yahoo.com/rss/topstories", function (data) {

---

So what is different here? The URL is different!

Now your question is two-folded, so finding the difference was only one part, let's recap the second part:

Why can't JavaScript work with both responses?

Implicitly this names the difference, so the reason is because those two URLs give different data. As the different data has not been presented, there is not much more that can be written to answer your question.

I hope the answer is useful to you and it helps you to continue your work. You can for example now look into the concrete data and find out that even so you expected the data to be the same, by directly comparing it, learn about the differences.