Query by an array of values from an ACF repeater Post Object sub field

• mtm

• March 7, 2024 at 2:41 pm

I am building a record label website in WordPress which has an artists and a releases post type.

The first part of my issue is as follows: I have a repeater field in releases called release_artist, containing a post object sub field called artist. I need to extract an array of post IDs from that sub field (sometimes a release has more than one artist associated).

For example:
Row 1: Artist = XXX (post ID 1)
Row 2: Artist = YYY (post ID 2)

The result I want to extract as a variable would in this case be the array 1,2.

This is my attempt so far at extracting that array as a variable:

if(have_rows('release_artist')): 
    while(have_rows('release_artist')): the_row();
        $select = get_sub_field_object('artist');
        $value = get_sub_field('artist');
        $artists = $select['value'];
    endwhile; 
    $artists_id = $artists->ID; // this should be an ID if only 1 repeater row, or array of IDs if more than 1
else: endif;

It’s returning only the ID of the sub field from the last repeater row.

The second part of my issue is this: I then need to use this array in a query to find other releases posts that have one or more of the artist(s) associated. So far I have the following, which is also currently wrong:

$artist_release_args = array(
    'post_type'     => 'releases',
    'meta_query'    => array(
        array(
            'key'       => 'release_artist_artist',
            'value'     => $artist_id, // this should give only results with one of the post IDs present in the array
            'compare'   => '='
        )
    ),
    'showposts'     => 6,
    'order'         => 'DESC',
    'post__not_in'  => array($post->ID),
);

$artist_release_query = new WP_Query($artist_release_args);

I’m pretty sure that meta_query is wrong, but I’m really not sure how to fix it.

In short:
Q1: How do I extract the desired array of post IDs from the repeater field?
Q2: How can I correctly compare this array against post IDs in the query?

I’m running WordPress 6.4.3 and ACF Pro 6.2.7 in a local environment.

• RemSEO

• March 28, 2024 at 11:50 am

Hi there,

About your first issue.
When you’re using $artists = $select['value']; in your loop : you reset $artists variable every time a loop is completed.

That’s why you store only the last value of your repeater field.

I assume you’re working on the same file template.
First, create an array of post IDs contained in your repeater field.
Then, use this array to build your custom WP_Query.

//Let's create an empty array
$artists = array();

//Loop over your repeater field
if(have_rows('release_artist')):
  while(have_rows('release_artist')): the_row();
    $related_artists = get_sub_field('artist');
    //Working on post object
    if( $related_artists && is_object($related_artists) && !is_wp_error($related_artists) ) {
      $artists[] = $related_artists->ID;
    }
    //Working on an array
    if( $related_artists && is_array($related_artists) ) {
      foreach($related_artists as $post_object) {
        if( is_object($post_object) && !is_wp_error($post_object) ) {
          $artists[] = $post_object->ID;
        }
      }
    }
  endwhile;
  //You should have an array containing all post IDs from release_artists repeater
  //error_log(print_r($artists, true));
endif;

//Probably better to check if everything is valid in $artists array from there

//Then you could use your array of post ID to build your custom Query
$paged = ( get_query_var( 'paged' ) ) ? get_query_var( 'paged' ) : 1;
$artist_release_args = array(
		'post_type' 	 	 => 'releases',
		'post_status' 	 => 'publish',
    'post__in'       => $artists,
		'orderby' 		 	 => 'modified',
		'order' 		 		 => 'DESC',
		'posts_per_page' => 6,
		'paged' 		 		 => $paged
);
$artist_release_query = new WP_Query($artist_release_args);

Don’t forget to check if your query has posts when you loop over it.
Add content-archive/content-none accordingly (or any template part needed).

Note that is_object() and !is_wp_error() checks are probably not strictly necessaries.
ACF normally returns an empty value if no post is selected in your sub field.