versioned_asset.php

<?php
/**
 * function for versioning static assets (images, css, js, etc.) by appending a file's last modified time to the filename (e.g. style.1234567890.css)
 * Requires Custom Htaccess rules to be in place (see below)
 * Apache .htaccess rules: 
 * <IfModule mod_rewrite.c>
 *  RewriteEngine On
 * RewriteCond %{REQUEST_FILENAME} !-f
 * RewriteRule ^(.+)\.(\d+)\.(js|css|png|jpg|gif)$ $1.$3 [L]
 * # to append apply on certain paths only, use the following:
 * # RewriteRule ^(/path/to/asset/)(.+)\.(\d+)\.(js|css|png|jpg|gif)$ $1$2.$4 [L]
 * </IfModule>
 * 
 * Usage:
 * <link rel="stylesheet" href="/css/<?= versioned_asset('style.css', 'css', 'css/') ?>" />
 * <script src="/js/<?= versioned_asset('script.js', 'js', 'js/') ?>"></script>
 * <img src="/img/<?= versioned_asset('logo.png', 'img', 'img/') ?>" />
 * 
 * @param string $filename The filename of the asset
 * @param string $type The type of asset (css, js, img, etc.)
 * @param string $path The path to the asset
 * @return string The versioned filename
 * 
 * @link https://gist.github.com/sumonst21/696dbbf03eaccf09667f60acb9f539e1
 * @copyright Copyright (c) 2022 Sumon Islam (sumonst21)
 */
function versioned_asset($filename, $type, $path = '') {
  $file = $path . $filename;
  $version = filemtime($file);
  $versioned_file = $filename . '.' . $version . '.' . $type;
  return $versioned_file;
}