public function get_prefix($class_name){
        /** @var RestBase $class_name */
        if( !empty($class_name::$prefix) ){
            return $class_name::$prefix;
        }else{
            $seg = explode('\\', $class_name);
            $base = $seg[count($seg) - 1];
            return $this->str->camel_to_hyphen($base);
        }
    }