[WordPress][WP Rocket] Edge case for mapped domains within the same installation. Clears an additional URL from cache when a given URL is cleared.

wp-rocket-clear-additional-urls.php

<?php
/**
 * Plugin Name: WP Rocket | Clear Additional URLs
 * Description: Clears an additional URL from cache when a given URL is cleared.
 * Version:     0.1
 * Author:      WP Rocket Support Team
 * Author URI:  http://wp-rocket.me/
 * Plugin URI:  https://gist.github.com/glueckpress/1c49dde98a361ec043fa
 * License:     GNU General Public License v3 or later
 * License URI: http://www.gnu.org/licenses/gpl-3.0.html
 */
 
/**
 * Clear additional URLs from cache when a given URL is cleared.
 * @param  array $urls URLs being cleared from cache
 * @return array       Altered array of URLs
 */
function wp_rocket_160322__clear_additional_urls( $urls ) {

	// If this URL is cleared from the cache…
	$check_for_this_url = 'http://your-url-here.com';

	// …clear this URL, too.
	$clear_this_url_too = 'http://your-other-url-here.com';

	if ( in_array( $check_for_this_url, $urls ) ) {
		$urls[] = $clear_this_url_too;
	}
	return $urls;
}
add_filter( 'rocket_clean_files', 'wp_rocket_160322__clear_additional_urls' );
add_filter( 'rocket_clean_domain_urls', 'wp_rocket_160322__clear_additional_urls' );