Cache breaker for gitted projects

cacheBreaker.php

/**
 * add a cache breaking get parameter to an url, that's based on the local git dir timestamp
 * @return string
 */
public function getCachebrokenUrl($url = "") {
  $version = $this->getVersionHash();
  $cachebrokenUrl = preg_replace("/((?:href|src)=\"[^?\"]*)(\")/", "$1?version=".$version."$2", $url);
  return $cachebrokenUrl;
}

/**
 * gets the .git directory's timestamp as unique id of a shop version
 * @return bool|int
 */
protected function getGitFolderDate(){
  return filemtime(self::LOCAL_PROJECT_BASE_PATH.DS.".git");
}

/**
 * get hashed version of the git timestamp
 * @return string
 */
protected function getVersionHash(){
  return hash("sha256", $this->getGitFolderDate());
}