[Snippet] NewsListing 6.3.3

Precondition Failed
The precondition on the request for the URL /fuchslock/manager/index.php evaluated to false.

$results = $modx->db->query("show columns from ".$modx->getFullTableName('site_content'));
while($dbfield = $modx->db->getRow($results))
   $dbfields[] = $dbfield['Field'];
if(isset($sortby) AND in_array($sortby,$dbfields)) {
   $sortby = $sortby;
} else {
   $sortby = "createdon";
}
    // check for valid field to sort by

$sortdir = isset($sortdir) ? strtoupper($sortdir) : "DESC";
    // get sort dir

$output = '';
    // initialize the blog variable 

$callby = ($showPublishedOnly)? 'getActiveChildren' : 'getAllChildren';

$resource = $modx->$callby($resourceparent, $sortby, $sortdir, $fields='id, pagetitle, longtitle, description, introtext, content, createdon, createdby, hidemenu');