Tumblr XML not loading - php

Question

I implemented the following code based on some code I found in another question:
Select specific Tumblr XML values with PHP
function getPhoto($photos, $desiredWidth) {
$currentPhoto = NULL;
$currentDelta = PHP_INT_MAX;
foreach ($photos as $photo) {
$delta = abs($desiredWidth - $photo['max-width']);
if ($photo['max-width'] <= $desiredWidth && $delta < $currentDelta) {
$currentPhoto = $photo;
$currentDelta = $delta;
}
}
return $currentPhoto;
}
$request_url = "http://ACCOUNT.tumblr.com/api/read?type=photo&start=0&num=30";
//$request_url = "tumblr.xml";
$xml = simplexml_load_file($request_url);
foreach ($xml->posts->post as $post) {
echo "<div class=\"item\"><a href='".$post['url']."'><img src='".getPhoto($post->{'photo-url'}, 250)."' width=\"250\" /></a></div>";
}
This code worked just fine on my development site, but when I pushed it live on another server, it would not load the external XML from Tumblr... It loaded the local text XML just fine (commented out in the code).
I'm waiting to get the account credentials from the client, so I can contact customer service and work with them...
In the meantime, does anyone have any ideas what might cause this?
Server settings?
Missing PHP code?

Answer 1

So, I ended up using cURL to load the XML... Here's the code that worked:
function getPhoto($photos, $desiredWidth) {
$currentPhoto = NULL;
$currentDelta = PHP_INT_MAX;
foreach ($photos as $photo) {
$delta = abs($desiredWidth - $photo['max-width']);
if ($photo['max-width'] <= $desiredWidth && $delta < $currentDelta) {
$currentPhoto = $photo;
$currentDelta = $delta;
}
}
return $currentPhoto;
}
$url="http://ACCOUNT.tumblr.com/api/read?type=photo&start=0&num=30";
$ch = curl_init();
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_URL, $url); // get the url contents
$data = curl_exec($ch); // execute curl request
curl_close($ch); // close curl request
$xml = new SimpleXMLElement($data);
foreach($xml->posts->post as $post) {
echo "<div class=\"item\"><a href='".$post['url']."'><img src='".getPhoto($post->{'photo-url'}, 250)."' width=\"250\" /></a></div>";
}