生成七牛云防盗链，防盗链基于时间戳

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/**
 * 生成七牛云防盗链，防盗链基于时间戳
 * 
 * @param  string  $url
 * @param  string  $antiLinkKey
 * @param  integer $deadline
 * @param  array   $query
 * @return void
 * 
 * @see https://developer.qiniu.com/fusion/kb/1670/timestamp-hotlinking-prevention
 */
public function getAntiLinkUrl(string $url, string $antiLinkKey, int $deadline, array $query = [])
{
    $urlInfo = parse_url($url);

    if (empty($urlInfo['path'])) {
        return null;
    }

    $qiniuOriginUrl = sprintf('/%s', ltrim($urlInfo['path'], '/'));

    $accessUrl = $qiniuOriginUrl;
    $accessUrl = implode("/", array_map("rawurlencode", explode("/", $accessUrl)));

    $key = $antiLinkKey;

    $hexDeadline = dechex($deadline);
    $lowerHexDeadline = strtolower($hexDeadline);

    $signString = sprintf('%s%s%s', $key, $accessUrl, $lowerHexDeadline);

    $sign = strtolower(md5($signString));

    $querystring = http_build_query(array_merge($query, [
        'sign' => $sign,
        't' => $lowerHexDeadline,
    ]));

    if (str_contains($url, '?')) {
        $url .= "&{$querystring}";
    } else {
        $url .= "?{$querystring}";
    }

    return $url;
}