private Callback<String> idConverterCallback(BlobInfo blobInfo) {
      return buildCallback(frontendMetrics.postIdConversionMetrics, convertedBlobId -> {
        restResponseChannel.setHeader(RestUtils.Headers.LOCATION, convertedBlobId);
        securityService.processResponse(restRequest, restResponseChannel, blobInfo, securityProcessResponseCallback());
      }, uri, LOGGER, finalCallback);
    }
After {@link IdConverter#convert} finishes, set the "Location" header and call
{@link SecurityService#processResponse}.
@param blobInfo the {@link BlobInfo} to use for security checks.
@return a {@link Callback} to be used with {@link IdConverter#convert}.
ambry-frontend/src/main/java/com/github/ambry/frontend/PostBlobHandler.java