如何为不在服务器上的脚本添加过期标头?

<script type="text/javascript" src="http://external.example.com/foo.js"></script>

至

<script type="text/javascript" src="external.php?url=http://external.example.com/foo.js"></script>

external.php类似于

<?php
header("Expire-stuff: something");
echo file_get_contents($_GET['url']);

$files = array('foo.js' => 'http://external/...');
if(isset($files[$_GET['file']]))
{
  echo file_get_contents($files[$_GET['file']]);
}

file_get_contents()当然会占用一些带宽,因此建议也缓存结果。

那是不可能的。

<?php
header('expire-header');

echo file_get_contents('http://www.extern.al/website/url');

<?php

$files = array(
    'ga.js' => 'https://ssl.google-analytics.com/ga.js',
    'bsa.js' => 'https://s3.buysellads.com/ac/bsa.js',
    'pro.js' => 'https://s3.buysellads.com/ac/pro.js'
);

if(isset($files[$_GET['file']])) {
    if ($files[$_GET['file']] == 'ga.js'){
        header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + ((60 * 60) * 48))); // 2 days for GA
    } else {
        header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60))); // Default set to 1 hour
    }

    echo file_get_contents($files[$_GET['file']]);
}

?>

https://www.catswhocode.com/blog/php-how-to-add-expire-headers-for-external-scripts

ExpiresActive On

ExpiresDefault "access plus 1 seconds"

ExpiresByType image/x-icon "access plus 2692000 seconds"

ExpiresByType image/jpeg "access plus 2692000 seconds"

ExpiresByType image/png "access plus 2692000 seconds"

ExpiresByType image/gif "access plus 2692000 seconds"

ExpiresByType application/x-shockwave-flash "access plus 2692000 seconds"

ExpiresByType text/css "access plus 2692000 seconds"

ExpiresByType text/javascript "access plus 2692000 seconds"

ExpiresByType application/x-javascript "access plus 2692000 seconds"

ExpiresByType text/html "access plus 600 seconds"

ExpiresByType application/xhtml+xml "access plus 600 seconds"