How to setup static assets caching with apache?

Question

I'd like to optimize caching of static assets (.js, .css, ... files) used in our web. My goal is based on this article (https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching#invalidating-and-updating-cached-responses).

In short - because these static assets tend to be updated ad-hoc (sometimes weekly, sometimes twice a day, ...) I'd like to cache them with far future expiration and give them unique names based on the content or modification date or similar. This should allow to have them cached for a long time but have them updated as soon as some change occurs.

Is this technique supported by Apache2 server? Or is there some middle ware system which handles fingerprints generating (to have unique asset names) and updating references to them in HTML file (which won't be cached at all)?

We use LAMP stack on our host.

Thank you in advance

Answer 1

There are a number of techniques, some better than others. One good one is to have the following configuration:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^(.+)\.(\d+)\.(bmp|css|cur|gif|ico|jpe?g|js|png|svgz?|webp|webmanifest)$ $1.$3 [L]
</IfModule>

This allows URLs of the form /i/filename.1433499948.gif - but the file that is actually read from disk is just /i/filename.gif parts 1 and 3 of the filename.

This Apache vhost/.htaccess stanza is from H5BP filename-based_cache_busting.conf file, and there are other examples of good practices in the repository.

That, combined with the H5BP mod_expires config, mean you will always be able to trivially renew the users local browser cache with just updating the reference to the file by a new name.