public static function authorizeUrl($params = null, $opts = null)
    {
        $params = $params ?: [];

        $base = ($opts && array_key_exists('connect_base', $opts)) ? $opts['connect_base'] : Stripe::$connectBase;

        $params['client_id'] = self::_getClientId($params);
        if (!array_key_exists('response_type', $params)) {
            $params['response_type'] = 'code';
        }
        $query = Util\Util::encodeParameters($params);

        return $base . '/oauth/authorize?' . $query;
    }