PHP CURL HEAD请求返回404，但浏览器/GET请求可正常加载页面的问题

开发者阿泽

2026-7-22

Zend Framework URL验证器S3跳转URL验证异常问题

我开发了一个Zend Framework URL验证器，先通过preg_match筛选格式无效的字符串，再用CURL发送HEAD请求（启用CURLOPT_NOBODY）排查404及连通性问题，还针对SSL相关错误做了兼容处理。但遇到一个用户常用的URL，它会跳转至S3的PDF链接：浏览器中原URL和S3链接均能正常显示PDF，但验证器返回404；直接访问S3链接则返回403，即使注释掉HTTP_X_REQUESTED_WITH请求头仍无效。我怀疑S3是否会针对HEAD请求做特殊限制，不想改为GET请求因为不需要响应体。

完整代码

<?php

class Oshk_ZendX_Validate_Url {
    static $debug = true;
    const PATTERN = '/^(https?:\/\/)?[^" ]+(\.[^" ]+)*$/';

    public static function isValid($value) {
        $STDERR = fopen("php://stderr", "w");
        $value = (string) $value;
        $matches = array();
        if (! preg_match(self::PATTERN, $value, $matches)) {
            fwrite($STDERR, sprintf("File '%s', line %d, value '%s' does not match pattern '%s'\n", __FILE__, __LINE__, $value, self::PATTERN));
            fclose($STDERR);
            return false;
        }
        if (! array_key_exists(1, $matches)) {
            $value = "https://$value";
        }
        if (self::$debug) {
            fwrite($STDERR, sprintf("File '%s', line %d, \$value = '%s', \$matches = %s", __FILE__, __LINE__, $value, print_r($matches, true)));
        }
        // URL looks well-formed. Ask curl to send a HEAD request to it
        $ch = curl_init($value);
        if ($ch === false) {
            throw new Exception("curl_init($value) failed!");
        }
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_HEADER, 0);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('HTTP_X_REQUESTED_WITH: XMLHttpRequest'));
        curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36');
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_NOBODY, true);
        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
        curl_setopt($ch, CURLOPT_FAILONERROR, true);
        if (self::$debug) {
            curl_setopt($ch, CURLOPT_VERBOSE, true);
            curl_setopt($ch, CURLOPT_STDERR, $STDERR);
        }
        $data = curl_exec($ch);
        $msg = curl_error($ch);
        $status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        if (self::$debug) {
            $allinfo = curl_getinfo($ch);
            fwrite($STDERR, sprintf("File '%s', line %d, \$allinfo = %s\n", __FILE__, __LINE__, print_r($allinfo, true)));
        }
        curl_close($ch);
        if (self::$debug) {
            fwrite($STDERR,  sprintf("File '%s', line %d, data = '%s'\n", __FILE__, __LINE__, substr($data, 0, 255)));
        }
        if(! strlen($data) && $status != 0 && false === strpos($msg, 'SSL')) {
            fwrite($STDERR, sprintf("File '%s', line %d, '%s' gives bad status code %d when accessed, with message '%s'\n", __FILE__, __LINE__, $value, $status, $msg));
            fclose($STDERR);
            return false;
        }
        if (self::$debug) {
            fwrite($STDERR, sprintf("File '%s', line %d, url = '%s'\n", __FILE__, __LINE__, $value));
            fwrite($STDERR, sprintf("File '%s', line %d, data = '%s'\n", __FILE__, __LINE__, substr($data, 0, 255)));
        }
        unset($data);
        if (self::$debug) {
            fwrite($STDERR, sprintf("File '%s', line %d, \$msg = '%s'\n", __FILE__, __LINE__, $msg));
            fwrite($STDERR, sprintf("File '%s', line %d, \$status = '%s'\n", __FILE__, __LINE__, $status));
            fwrite($STDERR, sprintf("File '%s', line %d, \$value = '%s'\n", __FILE__, __LINE__, $value));
        }
        if (($status >= 100 & $status < 400) || false !== strpos($msg, 'SSL')) {
            fclose($STDERR);
            return true;
        }
        fwrite($STDERR, sprintf("File '%s', line %d, '%s' gives bad status code %d when accessed, with message '%s'\n", __FILE__, __LINE__, $value, $status, $msg));
        fclose($STDERR);
        return false;
    }
}

echo var_dump(Oshk_ZendX_Validate_Url::isValid($argv[1]));

原URL测试输出

内容的提问来源于stack exchange，提问作者sootsnoot

PHP CURL HEAD请求返回404，但浏览器/GET请求可正常加载页面的问题

完整代码 #

原URL测试输出 #

完整代码

原URL测试输出