Select specific Tumblr XML values with PHP - php

Question

My goal is to embed Tumblr posts into a website using their provided XML. The problem is that Tumblr saves 6 different sizes of each image you post. My code below will get the first image, but it happens to be too large. How can I select one of the smaller-sized photos out of the XML if all the photos have the same tag of <photo-url>?
→ This is the XML from my Tumblr that I'm using: Tumblr XML.
→ This is my PHP code so far:
<?php
$request_url = "http://kthornbloom.tumblr.com/api/read?type=photo";
$xml = simplexml_load_file($request_url);
$title = $xml->posts->post->{'photo-caption'};
$photo = $xml->posts->post->{'photo-url'};
echo '<h1>'.$title.'</h1>';
echo '<img src="'.$photo.'"/>"';
echo "…";
echo "</br><a target=frame2 href='".$link."'>Read More</a>";
?>

Answer 1

The function getPhoto takes an array of $photos and a $desiredWidth. It returns the photo whose max-width is (1) closest to and (2) less than or equal to $desiredWidth. You can adapt the function to fit your needs. The important things to note are:
$xml->posts->post->{'photo-url'} is an array.
$photo['max-width'] accesses the max-width attribute on the <photo> tag.
I used echo '<pre>'; print_r($xml->posts->post); echo '</pre>'; to find out $xml->posts->post->{'photo-url'} was an array.
I found the syntax for accessing attributes (e.g., $photo['max-width']) at the documentation for SimpleXMLElement.
function getPhoto($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://kthornbloom.tumblr.com/api/read?type=photo";
$xml = simplexml_load_file($request_url);
foreach ($xml->posts->post as $post) {
echo '<h1>'.$post->{'photo-caption'}.'</h1>';
echo '<img src="'.getPhoto($post->{'photo-url'}, 450).'"/>"';
echo "...";
echo "</br><a target=frame2 href='".$post['url']."'>Read More</a>";
}

Answer 2

To get the photo with max-width="100":
$xml = simplexml_load_file('tumblr.xml');
echo '<h1>'.$xml->posts->post->{'photo-caption'}.'</h1>';
foreach($xml->posts->post->{'photo-url'} as $url) {
if ($url->attributes() == '100')
echo '<img src="'.$url.'" />';
}

Answer 3

Maybe this:
$doc = simplexml_load_file(
'http://kthornbloom.tumblr.com/api/read?type=photo'
);
foreach ($doc->posts->post as $post) {
foreach ($post->{'photo-url'} as $photo_url) {
echo $photo_url;
echo "\n";
}
}