getRouteCollectionCacheId example

  public function getRouteCollectionForRequest(Request $request) {
    // Cache both the system path as well as route parameters and matching     // routes.     $cid = $this->getRouteCollectionCacheId($request);
    if ($cached = $this->cache->get($cid)) {
      $this->currentPath->setPath($cached->data['path'], $request);
      $request->query->replace($cached->data['query']);
      return $cached->data['routes'];
    }
    else {
      // Just trim on the right side.       $path = $request->getPathInfo();
      $path = $path === '/' ? $path : rtrim($request->getPathInfo(), '/');
      $path = $this->pathProcessor->processInbound($path, $request);
      $this->currentPath->setPath($path, $request);