code: func truncate(e *auditinternal.Event) *auditinternal.Event {
  	// Make a shallow copy to avoid copying response/request objects.
  	newEvent := &auditinternal.Event{}
  	*newEvent = *e
  
  	newEvent.RequestObject = nil
  	newEvent.ResponseObject = nil
  	audit.LogAnnotation(newEvent, annotationKey, annotationValue)
  	return newEvent
  }
docs: // truncate removed request and response objects from the audit events,
  // to try and keep at least metadata.