OwnerKeysFromMeta returns a set of namespace/name keys for the owners of adopted objects with `annotationPrefix`.

Owned is used in object annotations to indicate an object is managed.

AlwaysExistsFunc is an ExistsFunc that always returns nil.

NoopObjectMissingFunc is an ObjectMissing func that does nothing.

AdoptionHandler implements handler.Handler to "adopt" an existing resource under the controller's management.

Adoptable is any type that can be labelled and annotated.

Annotator is any type that can have annotations added to it.

Labeler is any type that can have labels added to it.

Object is satisfied by any standard kube object.

ApplyFunc should apply a patch defined by the object A with server-side apply and should return the base type.

ExistsFunc should return nil if the object exists in the cluster, and an error otherwise.

IndexKeyFunc returns the name of an index to use and the value to query it for.