public function getSignedCookie(array $options)
    {
        foreach (['key_pair_id', 'private_key'] as $required) {
            if (!isset($options[$required])) {
                throw new \InvalidArgumentException("$required is required");
            }
        }

        $cookieSigner = new CookieSigner(
            $options['key_pair_id'],
            $options['private_key']
        );

        return $cookieSigner->getSignedCookie(
            isset($options['url']) ? $options['url'] : null,
            isset($options['expires']) ? $options['expires'] : null,
            isset($options['policy']) ? $options['policy'] : null
        );
    }