public function actionCsv($file, $delimiter = ',
 ', $enclosure = '"', $escape = '\\', $roles = '')
 {
     if (!Yii::app()->db) {
         throw new CException('No database configured');
     }
     if (!in_array('user', Yii::app()->db->schema->tableNames)) {
         throw new CException('No table "user" found; is yum installed?');
     }
     if (!$file) {
         throw new CException('No file given');
     }
     $data = file_get_contents($file);
     Yum::import($data, $delimiter, $enclosure, $escape, $roles);
 }