Fix custom permalinks in WordPress

fix-custom-permalinks.php

// fix custom permalinks
// useful for when importing posts using WP All Import as it doesn't set the custom permalink meta key
add_action( 'admin_footer', 'td_fix_custom_permalinks' );
function td_fix_custom_permalinks() {
	$post_type = 'resource';
	$args = array(
		'post_type' => $post_type,
		'posts_per_page' => -1,
	);
	$query = new WP_Query( $args );

	foreach( $query->posts as $post ) {
		$id = $post->ID;
		$permalink = get_permalink( $id );
		$slug = basename( $permalink );

		// check it post meta key exists
		$custom_permalink = get_post_meta( $id, 'custom_permalink', true );

		if ($slug != $custom_permalink ) {
			update_post_meta( $id, 'custom_permalink', $slug );
		}
	}
}