Enhance the garbage collector to periodically refresh the resources it
monitors (via discovery) to enable custom resource definition GC.
This implementation caches Unstructured structs for any kinds not
covered by a shared informer. The existing meta-only codec only supports
compiled types; an improved codec which supports arbitrary types could
be introduced to optimize caching to store only metadata for all
non-informer types.
Allow the list of resources the garbage collector controller should
ignore to be customizable, so downstream integrators can add their own
resources to the list, if necessary.
Automatic merge from submit-queue
replace global registry in apimachinery with global registry in k8s.io/kubernetes
We'd like to remove all globals, but our immediate problem is that a shared registry between k8s.io/kubernetes and k8s.io/client-go doesn't work. Since client-go makes a copy, we can actually keep a global registry with other globals in pkg/api for now.
@kubernetes/sig-api-machinery-misc @lavalamp @smarterclayton @sttts
Automatic merge from submit-queue (batch tested with PRs 38154, 38502)
Rename "release_1_5" clientset to just "clientset"
We used to keep multiple releases in the main repo. Now that [client-go](https://github.com/kubernetes/client-go) does the versioning, there is no need to keep releases in the main repo. This PR renames the "release_1_5" clientset to just "clientset", clientset development will be done in this directory.
@kubernetes/sig-api-machinery @deads2k
```release-note
The main repository does not keep multiple releases of clientsets anymore. Please find previous releases at https://github.com/kubernetes/client-go
```
The GC needs to build clients based only on Resource or Kind. Hoist the
restmapper out of the controller and the clientpool, support a new
ClientForGroupVersionKind and ClientForGroupVersionResource, and use the
appropriate one in both places.
