Turn OFF Cache for specific file with Apache - apache

Question

I have a page on a site which uses random() twig, in Firefox and Chrome it is prevented from working because it gets cached as soon as the page loads.
Is there a way to turn off caching of a particular file via the Apache configs, lets call it default.html or even better just turn off caching for the script part of that file but keep caching image files?
I have tried .htaccess but this does not work.
The only way currently that allows the script to work is to turn off caching globally via PHP headers:
<?php
header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');
header('Cache-Control: no-store, no-cache, must-revalidate');
header('Cache-Control: post-check=0, pre-check=0', FALSE);
header('Pragma: no-cache');
?>
But as I only need to turn off caching for an individual page, turning it off for everything seems crazy.

Answer 1

Figured it out, to target a specific file (in this case index.php), add this code to the bottom of .htaccess
<Files index.php>
FileETag None
Header unset ETag
Header set Cache-Control "max-age=0, no-cache, no-store, must-revalidate"
Header set Pragma "no-cache"
Header set Expires "Wed, 11 Jan 1984 05:00:00 GMT"
</Files>
Alternatively to target a specific selection of files, ie. I'd like to cache images but nothing else (files that match html, htm, js, css, php will not be cached):
<filesMatch "\.(html|htm|js|css|php)$">
FileETag None
Header unset ETag
Header set Cache-Control "max-age=0, no-cache, no-store, must-revalidate"
Header set Pragma "no-cache"
Header set Expires "Wed, 11 Jan 1984 05:00:00 GMT"
</filesMatch>
To check the .htaccess was being read I entered a few lines of rubbish at the bottom, found out it wasn't being read, renamed it from htaccess to .htaccess and it worked.