protected function getFormatFromUri($requestedUri)
    {
        $uriParts = explode('?', $requestedUri, 2);
        $uriWithoutGet = reset($uriParts);
        $uriAndFormat = explode('.', $uriWithoutGet);
        if (count($uriAndFormat) >= 2) {
            return end($uriAndFormat);
        }
        return null;
    }