: How to over ride a users cache when new assets / content are available Ive just run a google page speed test on my site and one of the things its suggested to do is use browser caching.

@Sent6035632

I agree with Stephen that "cache busting" is the way to go.


Is there anything else that could be done server side such as setting a new apache rule


You can use the apache rewrite module (make sure mod_rewrite is installed) to map a URL name starting with something common and map it to an actual file.

For example, you can use a rule like this in your .htaccess:

RewriteRule ^path/to/imagename-([0-9]+).jpg$ /path/to/image.jpg [L]


In this rule, if someone enters example.com/path/to/imagename-12345.jpg, then the file /path/to/image.jpg is loaded and the browser processes the image. the '([0-9]+)' means any number, and any number of digits. This can represent the version number. So requests to example.com/path/to/imagename-1.jpg and example.com/path/to/imagename-2.jpg will cause the server to load /path/to/image.jpg but the client browser won't know this. Theres tons of tutorials online on how to write regular expressions for apache.

Now that you got that down, you can do the same thing to your HTML files and other files. This rule in .htaccess is an example:

RewriteRule ^path/to/htmlname-([0-9]+).html$ /path/to/html.html [L]


Then the only changes you need to make in your code are all references to the assets.

I'd personally recommend a server side language and set variables to your asset files so that you only need to change the reference once, not 100 times.

For example, consider this HTML fragment:

<p>This is <a href="bones.html">a bone</a> and
we got lots of <a href="bones.html">bones</a> so
check out our <a href="bones.html">bones</a> today
or check <a href="bones.html">bones</a> tomorrow.</p>


Four links go to the exact same HTML file and it would be a pain to replace them all one by one. Now consider the same fragment in PHP:

<?php
$url="bones.html";
?>
<p>This is <a href="<?php echo $url; ?>">a bone</a> and
we got lots of <a href="<?php echo $url; ?>">bones</a> so
check out our <a href="<?php echo $url; ?>">bones</a> today
or check <a href="<?php echo $url; ?>">bones</a> tomorrow.</p>


Now here, all you have to do is changes bones.html once and the $url variable will match the new value right away.

** UPDATE **

Thanks to a comment and an overnight brain fart, I just realized that It would be much simpler to write rules to divert file requests of the same filename but different version numbers to the same file. I edited my answer to reflect this.

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