public function getAuthType()
    {

        if (isset($this->auth['username']) && isset($this->auth['password'])) {
            return self::HTTP_PASSWORD;
        }

        if (isset($this->auth['client_id']) && isset($this->auth['client_secret'])) {
            return self::URL_SECRET;
        }

        if (isset($this->auth['access_token'])) {
            return self::URL_TOKEN;
        }

        return -1;
    }