Wordpress: Iterative Parent Page if Custom Field Contains Page ID - wordpress

Question

I am trying to display a list based on the page. The list is built based on data in an ACF custom field, which is in a serialized array.
The list is for employees in a department. I am setting the parent page in Wordpress but want the employees to be listed on all child page. Employees may also need to be listed in multiple departments, so the ACF field is stored as a serialized array.
I have been able to get this to work if the current page is in the array, but am having problems when the data is for a parent, grandparent, etc. page. How can I iterate through this to find the first parent page that matches the criteria?
Relevant code (additional content is displayed, some included in case it is helpful in your answer):
$postid = get_the_ID();
$staffList = get_posts(array(
'post_type' => 'staff',
'meta_key' => 'position_order',
'orderby' => 'meta_value_num',
'order' => 'ASC',
'meta_query' => array(
'relation' => 'OR',
array(
'key' => 'ministries', // name of custom field
'value' => $postid,
'compare' => 'LIKE',
),
array(
'key' => 'administration', // name of custom field
'value' => $postid,
'compare' => 'LIKE',
)
)
));
if(( $staffList ) != '') {
foreach ( $staffList as $staff ) : setup_postdata( $people );
$pid = $staff->ID;
$featured_img_url = get_the_post_thumbnail_url($pid, 'full');
$highres = get_field('high_res', $pid);
$normal = get_field('normal', $pid);
$biofile = get_field('bio_file', $pid);
$scontent = $staff->post_content;
$contact = apply_filters('the_content',$scontent);
?>
<div class="profile">
<div class="text-center">
<img src="<?php echo $featured_img_url; ?>" width="130"
alt="<?php echo $staff->post_title; ?>">
</div>
<div class="profile__name"><?php echo $staff->post_title; ?></div>
<?php echo $contact; ?>
<?php if ( $biofile != "" ) { ?>
<span class="icon-file"></span> <?php echo $people->post_title; ?> Bio
<?php } ?>
</div>
<?php
endforeach;
wp_reset_postdata();
?>
<?php } endif; ?>
I'm thinking the query needs to be placed in a function, but having a problem getting it to run correctly and then iterate through parent posts until it finds a results. The concept is:
if no employees for current $pageid, then get $parent_pageid and run query. if no employees found, find grandparent_pageid and run query, etc., until either employees are found or there are no more parent pages.
I've found this: Recursive function to get the parent caegory description that seems like a good way to iterate, just having a problem modifying for my needs.
Thanks for your help!

Answer 1

This function will loop through parent posts until it returns results:
function get_staff_posts($post) {
$staffList = new WP_Query( array(
'post_type' => 'staff',
'meta_key' => 'position_order',
'orderby' => 'meta_value_num',
'order' => 'ASC',
'meta_query' => array(
'relation' => 'OR',
array(
'key' => 'ministries', // name of custom field
'value' => $post->ID,
'compare' => 'LIKE',
),
array(
'key' => 'administration', // name of custom field
'value' => $post->ID,
'compare' => 'LIKE',
),
),
));
$parent = $post->post_parent;
if( !$staffList->have_posts() && $parent != 0 )
get_staff_posts($parent);
return $staffList;
}
The function will return the query, so you could use it in your theme like this:
$staffList = get_staff_posts($post);
if( $staffList->have_posts() ):
while( $staffList->have_posts() ): $staffList->the_post();
// output
endwhile; wp_reset_postdata();
endif;