How to grab featured image URLs from posts with custom taxonomies? - php

Question

I had a look at this post which and copied some code which helped a little bit (the page isn't totally blank any more)
I'm trying to grab two URLs: The url to the full size image and the thumbnail version
From every post with a specific "field" from a custom taxonomy which I've created (I've created the taxonomy "art-type" and there are 3 options: Drawing, Print and Digital)
This is the code I've written so far:
<?php
$args = array(
'post_type' => 'art-piece', /* custom post type */
'taxonomy' => 'art-type', /* custom taxonomy */
'field' => 'slug',
'terms' => array('digital')
);
$gallery = get_posts ($args);
?>
<div class="zoom-gallery">
<div class="gallery-item">
<?php if (has_post_thumbnail( $post->ID ) ): ?>
<?php $url = wp_get_attachment_url( get_post_thumbnail_id($post->ID), 'thumbnail' ); ?>
<img src="<?php echo $url ?>" />
<?php endif; ?>
</div>
</div>
From what I can see there's nothing in the loop that's using any of the $args I've specified. In theory this should grab all the featured images regardless or post type, taxonomy etc. but they're not coming up for me at all. The page is just totally blank

Answer 1

It looks to me that you're not looping through the results of the get_posts() call. Try changing the code to match the updated code I posted below.
What it does is it loops through each 'post' stored in the $gallery variable.
Apologies for not having enough time to give a more in-depth explanation however I'll come back and elaborate more if this works for you.
<?php
$args = array(
'post_type' => 'art-piece', /* custom post type */
'tax_query' => array(
array(
'taxonomy' => 'art-type', /* custom taxonomy */
'field' => 'slug',
'terms' => array('digital')
),
),
);
$gallery = get_posts($args); // removed space between function name and opening bracket
foreach ( $gallery as $post ) : setup_postdata( $post ); // added this loop
?>
<div class="zoom-gallery">
<div class="gallery-item">
<?php if (has_post_thumbnail( $post->ID ) ): ?>
<?php $url = wp_get_attachment_url( get_post_thumbnail_id($post->ID), 'thumbnail' ); ?>
<img src="<?php echo $url ?>" />
<?php endif; ?>
</div>
</div>
<?php endforeach; // ending the loop
wp_reset_postdata(); // reset $post so we don't interfere with the main WP_Query
?>