includeFile snippet is to include any file in MODX's page, either in resource, template, or chunk

includeFile.snippet.php

<?php

/**
 * includeFile snippet is to include any file in MODX's page, either in resource, template, or chunk
 *
 * @author      goldsky <goldsky@virtudraft.com>
 * @copyright   Copyright (c) 2015, goldsky
 * @example     [[!includeFile? &file=`[[++core_path]]statics/chunks/mychunk.chunk.tpl`]]
 *              [[!includeFile? &file=`[[++core_path]]statics/snippets/mysnippet.snippet.php`]]
 *
 *              Adding "&toPlaceholder" parameter ...
 *              [[!includeFile?
 *              &file=`[[++core_path]]statics/chunks/mychunk.chunk.tpl`
 *              &toPlaceholder=`my_placeholder`
 *              ]]
 *              ... creates [[+my_placeholder]] for multiple calls in the page
 */
if (!isset($file) || $file == "") {
    $modx->log(modX::LOG_LEVEL_ERROR, "[includeFile] File was not defined!");
    return;
}

if (!file_exists($file)) {
    $modx->log(modX::LOG_LEVEL_ERROR, "[includeFile] could not find file: " . $file);
    return;
}

$pathinfo = pathinfo($file);
if ($pathinfo['extension'] === 'php') {
    $content = include $file;
} else {
    ob_start();
    include $file;
    $content = ob_get_contents();
    ob_end_clean();
}

if ($toPlaceholder) {
    $modx->setPlaceholder($toPlaceholder, $content);
    return;
}

return $content;