cache-busting.php

<?php

function assets($path)
{
  $file = realpath($path);
  if (!file_exists($file)) throw new Exception("Le fichier {$file} n'existe pas");

  $mtime = filemtime($file);
  $path_info = pathinfo($path);

  $newPath = $path_info['dirname'] . '/' . $path_info['filename'] . '.' . hash('md5', $mtime) . '.' . $path_info['extension'];

  $newRealPath = realpath($newPath);

  if (!file_exists($newRealPath)) {
    copy($file, $newRealPath);
  }

  return $newPath;
}
?>
// Utilization
<img src="<?= assets("img/coffee.jpg") ?>" alt="coffeeeeeeeeeeee"/>