public function login($login, $api_key)
    {
        if (empty($login) || !is_string($login)) {
            throw new \InvalidArgumentException('Argument "login" cannot be empty and must be a string');
        }

        if (empty($login) || !is_string($api_key)) {
            throw new \InvalidArgumentException('Argument "api_key" cannot be empty and must be a string');
        }

        $this->auth = [
            'login'         => $login,
            'password_hash' => $api_key,
        ];
    }