DefaultIgnoredResources returns the default set of resources that the garbage collector controller should ignore.

GetDeletableResources returns all resources from discoveryClient that the garbage collector should recognize and work with.

NewUIDCache returns a UIDCache.

GarbageCollector runs reflectors to watch for changes of managed API objects, funnels the results to a single-threaded dependencyGraphBuilder, which builds a graph caching the dependencies among objects.

GraphBuilder: based on the events supplied by the informers, GraphBuilder updates uidToNode, a graph that caches the dependencies as we know, and enqueues items to the attemptToDelete and attemptToOrphan.

UIDCache is an LRU cache for uid.