/**
  * @param \Illuminate\Http\Request $request
  * @param \Closure                 $next
  *
  * @return Request
  */
 public function handle(Request $request, Closure $next)
 {
     if ($this->responseCache->hasCached($request)) {
         return $this->responseCache->getCachedResponseFor($request);
     }
     $response = $next($request);
     if ($this->responseCache->shouldCache($request, $response)) {
         $this->responseCache->cacheResponse($request, $response);
     }
     return $response;
 }
 /**
  *  Flush the cache.
  */
 public function flush()
 {
     $this->cache->flush();
 }