@Override
    public Future<String> convert(RestRequest restRequest, String input, BlobProperties blobProperties,
        Callback<String> callback) {
      if (!isOpen) {
        throw new IllegalStateException("IdConverter closed");
      }
      if ((restRequest.getRestMethod() == RestMethod.PUT || restRequest.getRestMethod() == RestMethod.POST)
          && RestUtils.getRequestPath(restRequest).matchesOperation(Operations.NAMED_BLOB)) {
        restRequest.setArg(RestUtils.InternalKeys.NAMED_BLOB_VERSION, -1L);
      }
      return completeOperation(input, blobProperties, callback);
    }
Implementation of {@link IdConverterFactory} that returns exceptions.
ambry-frontend/src/test/java/com/github/ambry/frontend/FrontendRestRequestServiceTest.java