private function _get_request_body()
 {
     //  format
     switch ($this->request->format) {
         case 'json':
             // json, .json
             return mgm_format::to_array(mgm_format::from_json($this->request->data['body']));
             break;
         case 'phps':
             // php serialize, .phps
             return mgm_format::to_array(mgm_format::from_phps($this->request->data['body']));
             break;
         case 'php':
             // php array, .php
             return mgm_format::to_array(mgm_format::from_php($this->request->data['body']));
             break;
         case 'xml':
             // xml, .xml
         // xml, .xml
         default:
             return mgm_format::to_array(mgm_format::from_xml($this->request->data['body']));
             break;
     }
 }