code: func (ub *URLBuilder) BuildBlobUploadURL(name reference.Named, values ...url.Values) (string, error) {
  	route := ub.cloneRoute(RouteNameBlobUpload)
  
  	uploadURL, err := route.URL("name", name.Name())
  	if err != nil {
  		return "", err
  	}
  
  	return appendValuesURL(uploadURL, values...).String(), nil
  }
docs: // BuildBlobUploadURL constructs a url to begin a blob upload in the
  // repository identified by name.