Writing kcp-aware controllers

Keys for objects in listers/indexers

When you need to get an object from a kcp-aware lister or an indexer, you can't just pass the object's name to the Get() function, like you do with a typical controller targeting Kubernetes. Projects using kcp's copy of client-go are using a modified key function.

Here are what keys look like for an object foo for both cluster-scoped and namespace-scoped varieties:

Organization	Workspace	Logical Cluster	Namespace	Key
-	-	root	-	root
-	-	root	default	default/root
root	my-org	root:my-org	-	root:my-org
root	my-org	root:my-org	default	default/root:my-org
my-org	my-workspace	my-org:my-workspace	-	my-org:my-workspace
my-org	my-workspace	my-org:my-workspace	default	default/my-org:my-workspace

Encoding/decoding keys

Use the github.com/kcp-dev/apimachinery/pkg/cache package to encode and decode keys.