public function process()
{
$options = ['output_type' => 'xml', 'verbosity' => 'pretty', 'escaping' => ['markup'], 'version' => 'xmlrpc', 'encoding' => 'utf-8'];
$response = xmlrpc_server_call_method($this->server, file_get_contents('php://input'), null, $options);
header('Content-Type: text/xml; charset="utf-8"');
echo $response;
}