如何在PHP中从HTTP接受头中选择内容类型

你可以利用 apache's mod_negotiation module . 通过这种方式,您可以使用模块提供的全部协商功能,包括 您自己的偏好 对于内容类型(例如,“我真的想交付application/xhtml+xml,除非客户机非常喜欢其他东西”)。 碱性溶液:

• 使用创建.htaccess文件

  AddHandler type-map .var

  作为内容
• 创建一个文件foo.var

  URI: foo
  
  URI: foo.php/html
  Content-type: text/html; qs=0.7
  
  URI: foo.php/xhtml
  Content-type: application/xhtml+xml; qs=0.8

  作为内容
• 使用创建文件foo.php

  <?php
  echo 'selected type: ', substr($_SERVER['PATH_INFO'], 1);

  作为内容。
• 请求 http://localhost/whatever/foo.var

要使其工作,需要启用mod_协商,为addhandler和 AcceptPathInfo 未禁用$_server['path_info']。
我的火狐发送“accept:text/html,application/xhtml+xml,application/xml;q=0.9, / ;q=0.8”和示例.var map结果是“selected type:xhtml”。
您可以使用其他“调整”来消除路径信息或请求foo的需要 VaR 但基本概念是:让mod_协商以脚本可以“读取”所选内容类型的方式将请求重定向到PHP脚本。

那么,是否有人知道要选择的经过测试的一段PHP代码

我的库中的小片段:

function getBestSupportedMimeType($mimeTypes = null) {
    // Values will be stored in this array
    $AcceptTypes = Array ();

    // Accept header is case insensitive, and whitespace isn’t important
    $accept = strtolower(str_replace(' ', '', $_SERVER['HTTP_ACCEPT']));
    // divide it into parts in the place of a ","
    $accept = explode(',', $accept);
    foreach ($accept as $a) {
        // the default quality is 1.
        $q = 1;
        // check if there is a different quality
        if (strpos($a, ';q=')) {
            // divide "mime/type;q=X" into two parts: "mime/type" i "X"
            list($a, $q) = explode(';q=', $a);
        }
        // mime-type $a is accepted with the quality $q
        // WARNING: $q == 0 means, that mime-type isn’t supported!
        $AcceptTypes[$a] = $q;
    }
    arsort($AcceptTypes);

    // if no parameter was passed, just return parsed data
    if (!$mimeTypes) return $AcceptTypes;

    $mimeTypes = array_map('strtolower', (array)$mimeTypes);

    // let’s check our supported types:
    foreach ($AcceptTypes as $mime => $q) {
       if ($q && in_array($mime, $mimeTypes)) return $mime;
    }
    // no mime-type found
    return null;
}

示例用法:

$mime = getBestSupportedMimeType(Array ('application/xhtml+xml', 'text/html'));

Pear::HTTP 1.4.1有一个方法 string negotiateMimeType( array $supported, string $default)

<?php
require 'HTTP.php';

foreach(
  array(
    'text/*;q=0.3, text/html;q=0.7, text/html;level=1, text/html;level=2;q=0.4, */*;q=0.5',
    'text/*;q=0.3, text/html;q=0.8, application/xhtml+xml;q=0.7, */*;q=0.2',
    'text/*;q=0.3, text/html;q=0.7, */*;q=0.8',
    'text/*, application/xhtml+xml',
    'text/html, application/xhtml+xml'
  ) as $testheader) {  
  $_SERVER['HTTP_ACCEPT'] = $testheader;

  $http = new HTTP;
  echo $testheader, ' -> ',
    $http->negotiateMimeType( array('application/xhtml+xml', 'text/html'), 'application/xhtml+xml'),
    "\n";
}

印刷品

text/*;q=0.3, text/html;q=0.7, text/html;level=1, text/html;level=2;q=0.4, /;q=0.5 -> application/xhtml+xml
text/*;q=0.3, text/html;q=0.8, application/xhtml+xml;q=0.7, */*;q=0.2 -> text/html
text/*;q=0.3, text/html;q=0.7, */*;q=0.8 -> application/xhtml+xml
text/*, application/xhtml+xml -> application/xhtml+xml
text/html, application/xhtml+xml -> text/html

只是为了记录, Negotiation 是处理内容协商的纯PHP实现。

将@maciej-ebkowski和@chachacham15解决方案与我的问题修复和改进合并。如果你通过 $desiredTypes = 'text/*' 和 Accept 包含 text/html;q=1 然后 text/html 将被退回。

/**
 * Parse, sort and select best Content-type, supported by a user browser.
 *
 * @param string|string[] $desiredTypes The filter of desired types. If &null then the all supported types will returned.
 * @param string $acceptRules Supported types in the HTTP Accept header format. $_SERVER['HTTP_ACCEPT'] by default.
 * @return string|string[]|null Matched by $desiredTypes type or all accepted types.
 * @link Inspired by http://stackoverflow.com/a/1087498/3155344
 */
function resolveContentNegotiation($desiredTypes = null, $acceptRules = null)
{
    if (!$acceptRules) {
        $acceptRules = @$_SERVER['HTTP_ACCEPT'];
    }
    // Accept header is case insensitive, and whitespace isn't important.
    $acceptRules = strtolower(str_replace(' ', '', $acceptRules));

    $sortedAcceptTypes = array();
    foreach (explode(',', $acceptRules) as $acceptRule) {
        $q = 1; // the default accept quality (rating).
        // Check if there is a different quality.
        if (strpos($acceptRule, ';q=') !== false) {
            // Divide "type;q=X" into two parts: "type" and "X"
            list($acceptRule, $q) = explode(';q=', $acceptRule, 2);
        }
        $sortedAcceptTypes[$acceptRule] = $q;
    }
    // WARNING: zero quality is means, that type isn't supported! Thus remove them.
    $sortedAcceptTypes = array_filter($sortedAcceptTypes);
    arsort($sortedAcceptTypes, SORT_NUMERIC);

    // If no parameter was passed, just return parsed data.
    if (!$desiredTypes) {
        return $sortedAcceptTypes;
    }

    $desiredTypes = array_map('strtolower', (array) $desiredTypes);

    // Let's check our supported types.
    foreach (array_keys($sortedAcceptTypes) as $type) {
        foreach ($desiredTypes as $desired) {
            if (fnmatch($desired, $type)) {
                return $type;
            }
        }
    }

    // No matched type.
    return null;
}

PEAR's HTTP2 library 支持分析所有类型的 Accept 标题。它可以通过安装 composer 还有梨。

示例见 documentation 或 my blog post .

http://www.dev-archive.net/articles/xhtml.html#content-negotiation 它是用Perl编写的,但它的布局很清楚,只包含一些if/else和regex。将它移植到PHP应该很简单。

客户机可以接受响应中的mime类型列表。另一方面,响应的顺序对于客户端非常重要。 PHP Pear HTTP2 最好是处理语言、字符集和mimetype。

$http = new HTTP2();
$supportedTypes = array(
    'text/html',
    'application/json'
);

$type = $http->negotiateMimeType($supportedTypes, false);
if ($type === false) {
    header('HTTP/1.1 406 Not Acceptable');
    echo "You don't want any of the content types I have to offer\n";
} else {
    echo 'I\'d give you data of type: ' . $type . "\n";
}

以下是一个很好的教程: https://cweiske.de/tagebuch/php-http-negotiation.htm