在浏览器中强制缓存更新

Question

I'm using Minify ( https://code.google.com/p/minify/ ) to compress and combine ~30 css files and ~10 javascript files. I've created a group configuration for those files, which is basically an array with the filenames.

Works like a charm, except when one of the scripts is modified: browser cache is not timely update. I used to get a last modified timestamp for each file (using filemtime) to overrule browser caching:

$time = '?' . filemtime( $filename );
$output = '<link type="text/css" rel="stylesheet" href="'.$file_path.'?'.$time.'" />';

I could loop through all 40 files to get the latest timestamp, but that is a very ugly solution. Another way would be eg to have a crobjob check it and write the timestamp to a file, which I can then include.

Any other ways before I'm inventing the wheel again?

Answer 1

您可以不只是添加：

src="path/to/file.css?v=<?php date(dmy); ?>"

Answer 2

Just get the modification time of the $file_path ...? Personally, I have a much more reasonable number of files (two or three) and each one is individually cached with its mtime . Works beautifully.

Answer 3

I can suggest you a way that you need to define a rewrite rule and implement a handler for static file load. Let say it is assethandler.php , and your rewrite rule;

RewriteRule ^nocache/(.*?)$ assethandler.php?f=$1 [QSA,L]

And in php you can use Cache-Control and Expires for getting always latest file;

header("Cache-Control: no-cache, must-revalidate");
header("Expires: Mon, 01 Jul 1990 05:00:00 GMT"); // past date
readfile('path_to_static_files/' . $_GET['f']);

and your static file requests will be like;

<script src="nocache/your.js"/>

Simply, when you make a request to nocache/filename this will be handled as assethandler.php?f=filename and in this handler, cache always disabled and file content served as latest content