304: Not modified and front end caching

Question

I am using a PHP script to serve files. I would like to be able to send back a 304 not modified header in my http response if the file has not changed since th

Answer 1

This article will answer all your questions on caching

I found that adding

RewriteRule .* - [E=HTTP_IF_MODIFIED_SINCE:%{HTTP:If-Modified-Since}]
RewriteRule .* - [E=HTTP_IF_NONE_MATCH:%{HTTP:If-None-Match}]

To the bottom of my htaccess file (below all rewriterule) worked.