Here’s what I’ve done so far:
<?php
//filter by custom field
if(isset($_GET['shift']))
$args['meta_query'][] = array(
'key' => 'shift',
'value' => $shift,
'compare' => 'LIKE'
);
//filtered by taxonomy
if(isset($terms1))
$args['tax_query'][] = array(
'taxonomy' => 'category',
'field' => 'slug',
'terms' => $terms1,
'operator' => 'IN',
// Don't know how to filter by related post's custom fields
$proSearch_query = new WP_Query($args);
while ($proSearch_query->have_posts()){
$proSearch_query->the_post();
$result[] = array(
"id" => get_the_ID(),
"title" => get_the_title(),
"rel_university" => get_field('uni')[0]->post_name,
//returns related post's custom field:
"ranking" => get_field('university')[0]->ranking,
);
}
echo json_encode($result);
die();
?>
