protected function fail($message = null, $validation = null)
    {
        $this->trigger('json-fail', $this, $message, $validation);
        $this->trigger('response-fail', $this, $message, $validation);

        $json = array('error' => true);

        if($message) {
            $json['message'] = $message;
        }

        if($validation) {
            $json['validation'] = $validation;
        }

        $body = json_encode($json, JSON_PRETTY_PRINT);

        $this->response
            ->set('headers', 'Content-Type', 'text/json')
            ->set('body', $body);

        return $body;
    }