crop-monitor/core/components/phpthumbof/elements/plugins/phpthumbofcachemanager.plugin.php

<?php
/*
 * Handles cache cleanup
 * pThumb
 * Copyright 2013 Jason Grant
 *
 * Please see the GitHub page for documentation or to report bugs:
 * https://github.com/oo12/phpThumbOf
 *
 * pThumb is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option) any
 * later version.
 *
 * pThumb is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * phpThumbOf; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA
 */

if ($modx->event->name === 'OnSiteRefresh') {
	if (!$modx->loadClass('pThumbCacheCleaner', MODX_CORE_PATH . 'components/phpthumbof/model/', true, true)) {
		$modx->log(modX::LOG_LEVEL_ERROR, '[pThumb] Could not load pThumbCacheCleaner class.');
		return;
	}
	static $pt_settings = array();
	$pThumb = new pThumbCacheCleaner($modx, $pt_settings, array(), true);
	$pThumb->cleanCache();
}