// return an error if the specified object cannot be updated.
	PrepareObjectForStorage(obj runtime.Object) error
	// ObjectResourceVersion returns the resource version (for persistence) of the specified object.
	// Should return an error if the specified object does not have a persistable version.
	ObjectResourceVersion(obj runtime.Object) (uint64, error)

	// ParseResourceVersion takes a resource version argument and

		attribute.String("key", key),
		attribute.String("type", getTypeName(obj)),
		attribute.String("resource", s.groupResourceString),
	)
	defer span.End(500 * time.Millisecond)
	if version, err := s.versioner.ObjectResourceVersion(obj); err == nil && version != 0 {
		return storage.ErrResourceVersionSetOnCreate
	}
	if err := s.versioner.PrepareObjectForStorage(obj); err != nil {
		return fmt.Errorf("PrepareObjectForStorage failed: %v", err)

	object, ok := obj.(runtime.Object)
	if !ok {
		return nil, 0, fmt.Errorf("obj does not implement runtime.Object interface: %v", obj)
	}
	resourceVersion, err := w.versioner.ObjectResourceVersion(object)
	if err != nil {
		return nil, 0, err
	}
	return object, resourceVersion, nil
}

// processEvent is safe as long as there is at most one call to it in flight
// at any point in time.