A general purpose script to prime a MODX site cache.

RegenCache.php

<?php
$tstart = microtime(true);
set_time_limit(0);

require 'config.core.php';
require MODX_CORE_PATH . 'model/modx/modx.class.php';

$modx = modX::getInstance();

$modx->initialize('mgr');

$modx->setLogLevel(modX::LOG_LEVEL_INFO);
$modx->setLogTarget('ECHO');

$modx->log(modX::LOG_LEVEL_INFO, "Regenerating MODX Cache");
try {
    $iterator = $modx->getIterator('modContext', array('key:!=' => 'mgr'));
    foreach ($iterator as $context) {
        if ($modx->switchContext($context->get('key'))) {
            $modx->setLogLevel(modX::LOG_LEVEL_INFO);
            $modx->setLogTarget('ECHO');
            $modx->log(modX::LOG_LEVEL_INFO, "Processing Resources in Context {$context->get('key')}");
            $map = array_reverse($modx->context->aliasMap, true);
            $modx->log(modX::LOG_LEVEL_INFO, "Processing aliasMap: " . print_r($map, true));
            $curl = curl_init();
            foreach ($map as $uri => $id) {
                $resource = $modx->getObject('modResource', $id);
                if ($resource && $resource->get('cacheable')) {
                    if (in_array($resource->get('class_key'), array('modDocument', 'modSymLink', 'modStaticResource'))) {
                        $url = $modx->makeUrl($resource->get('id'), '', '', 'full');
                        if (!empty($url)) {
                            $modx->log(modX::LOG_LEVEL_INFO, "Requesting Resource at {$url}");
                            curl_setopt($curl, CURLOPT_URL, $url);
                            curl_setopt($curl, CURLOPT_FAILONERROR, false);
                            curl_setopt($curl, CURLOPT_FOLLOWLOCATION, false);
                            curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
                            curl_exec($curl);
                            $modx->log(modX::LOG_LEVEL_INFO, "Updated cache for resource at {$url}");
                        }
                    }
                }
            }
            curl_close($curl);
        } else {
            $modx->log(modX::LOG_LEVEL_ERROR, "RegenCache: Could not switchContext({$context->get('key')})");
        }
    }
} catch (Exception $e) {
    $tend = microtime(true);
    $totalTime= sprintf("%2.4f seconds", ($tend - $tstart));
    $modx->log(modX::LOG_LEVEL_ERROR, "RegenCache failed in {$totalTime}: {$e->getMessage()}");
}

$tend = microtime(true);
$totalTime= sprintf("%2.4f seconds", ($tend - $tstart));

$modx->log(modX::LOG_LEVEL_INFO, "RegenCache executed in {$totalTime}");