@Override
  public Future<String> stitchBlob(BlobProperties blobProperties, byte[] userMetadata, List<ChunkInfo> chunksToStitch,
      PutBlobOptions options, Callback<String> callback, QuotaChargeCallback quotaChargeCallback) {
    return completeOperation(TestUtils.getRandomString(10), callback, OpType.StitchBlob);
  }
Enumerates the different operation types in the router.
ambry-frontend/src/test/java/com/github/ambry/frontend/FrontendRestRequestServiceTest.java