// Attaches Cache-Busting functionality to an endpoint
//   - Sets ETag header to provided hash
//   - Replies with 304 Not Modified, if If-None-Match header matches hash
//
// hash should be the value of calculateETag on object. If hash is empty, then
// the object is simply serialized without E-Tag functionality
func ServeHTTPWithETag(
	object runtime.Object,
	hash string,
	targetGV schema.GroupVersion,

                headers = [
                    'x-amz-id-2': X_AMZ_ID_2,
                    'x-amz-request-id': X_AMZ_REQUEST_ID,
                    'Date': DATE_HEADER,
                    "ETag": { calculateEtag(file) },
                    'Server': SERVER_AMAZON_S3
                ]
            }
        }
        expect(httpStub)
    }

                }
            }
            response {
                status = 200
                headers = [
                    'Date'            : DATE_HEADER,
                    "ETag"            : { calculateEtag(file) },
                    'Server'          : SERVER_GCS
                ]
                body = { '{}' }
            }
        }
        expect(httpStub)
    }

	cacheLoad := rdm.cache.Load()
	if cacheLoad != nil {
		return cacheLoad
	}
	response := apidiscoveryv2.APIGroupDiscoveryList{
		Items: rdm.calculateAPIGroupsLocked(),
	}
	etag, err := calculateETag(response)
	if err != nil {
		klog.Errorf("failed to calculate etag for discovery document: %s", etag)
		etag = ""
	}
	cached := &cachedGroupList{
		cachedResponse:     response,
		cachedResponseETag: etag,