Function buildChanges

controllers/trace/util.go:517–587

(oldObjectMap, newObjectMap map[model.GVKNObjKey]client.Object,
	descriptionFormat func(client.Object, client.Object, tracev1.ObjectChangeType, *schema.GroupVersionKind) (string, *string))

}

func buildChanges(oldObjectMap, newObjectMap map[model.GVKNObjKey]client.Object,
	descriptionFormat func(client.Object, client.Object, tracev1.ObjectChangeType, *schema.GroupVersionKind) (string, *string)) []tracev1.ObjectChange {
	// calculate createSet, deleteSet and updateSet
	newObjectSet := sets.KeySet(newObjectMap)
	oldObjectSet := sets.KeySet(oldObjectMap)
	createSet := newObjectSet.Difference(oldObjectSet)
	updateSet := newObjectSet.Intersection(oldObjectSet)
	deleteSet := oldObjectSet.Difference(newObjectSet)

	// build new slice of reconciliation changes from last round calculation
	var changes []tracev1.ObjectChange
	allObjectMap := map[tracev1.ObjectChangeType]sets.Set[model.GVKNObjKey]{
		tracev1.ObjectCreationType: createSet,
		tracev1.ObjectUpdateType:   updateSet,
		tracev1.ObjectDeletionType: deleteSet,
	}
	// Why not use for-range on allObjectMap:
	// Order is important here. A for-range on a map can't guarantee the built changes' order.
	for _, changeType := range []tracev1.ObjectChangeType{tracev1.ObjectCreationType, tracev1.ObjectUpdateType, tracev1.ObjectDeletionType} {
		changeSet := allObjectMap[changeType]
		for key := range changeSet {
			var oldObj, newObj client.Object
			if oldObjectMap != nil {
				oldObj = oldObjectMap[key]
			}
			if newObjectMap != nil {
				newObj = newObjectMap[key]
			}
			obj := newObj
			if changeType == tracev1.ObjectDeletionType {
				obj = oldObj
			}
			if changeType == tracev1.ObjectUpdateType &&
				(oldObj == nil || newObj == nil || oldObj.GetResourceVersion() == newObj.GetResourceVersion()) {
				continue
			}
			isEvent := isEvent(&key.GroupVersionKind)
			if isEvent && changeType == tracev1.ObjectDeletionType {
				continue
			}
			var (
				ref             *corev1.ObjectReference
				eventAttributes *tracev1.EventAttributes
			)
			if isEvent {
				changeType = tracev1.EventType
				evt, _ := obj.(*corev1.Event)
				ref = &evt.InvolvedObject
				eventAttributes = &tracev1.EventAttributes{
					Name:   evt.Name,
					Type:   evt.Type,
					Reason: evt.Reason,
				}
			} else {
				ref = objectRefToReference(key, obj.GetUID(), obj.GetResourceVersion())
			}
			description, localDescription := descriptionFormat(oldObj, newObj, changeType, &key.GroupVersionKind)
			change := tracev1.ObjectChange{