### API Server Aggregator
* Rename kubernetes-discovery to kube-aggregator ([#39619](https://github.com/kubernetes/kubernetes/pull/39619), [@deads2k](https://github.com/deads2k))
* Fix connection upgrades through kubernetes-discovery ([#38724](https://github.com/kubernetes/kubernetes/pull/38724), [@deads2k](https://github.com/deads2k))

#### Generic API Server

- Volume Cloning: Duplicate a PersistentVolumeClaim and underlying storage volume using the Kubernetes API via CSI.
- CSIDriver Kubernetes API Object: Simplifies CSI driver discovery and allows CSI Drivers to customize Kubernetes behavior.

SIG Storage is also introducing the following new storage features as alpha in Kubernetes 1.18:

* Pass-through volume MountOptions to global mount (NodeStageVolume) on the node for CSI ([#80191](https://github.com/kubernetes/kubernetes/pull/80191), [@davidz627](https://github.com/davidz627))
* Fix error in `kubeadm join --discovery-file` when using discovery files with embedded credentials ([#80675](https://github.com/kubernetes/kubernetes/pull/80675), [@fabriziopandini](https://github.com/fabriziopandini))

* kube-apiserver now includes all registered API groups in discovery, including registered extension API group/versions for unavailable extension API servers. ([#66932](https://github.com/kubernetes/kubernetes/pull/66932), [@nilebox](https://github.com/nilebox))

import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;

/**
 * Helper class for managing Fess plugins and artifacts.
 * This class provides functionality to discover, install, and manage various types of plugins
 * including data stores, themes, ingest processors, scripts, web applications, thumbnails, and crawlers.
 */
public class PluginHelper {
    /** Logger instance for this class */

* attachdetach controller attaches volumes immediately when Pod's PVCs are bound ([#66863](https://github.com/kubernetes/kubernetes/pull/66863), [@cofyc](https://github.com/cofyc))
* kube-apiserver now includes all registered API groups in discovery, including registered extension API group/versions for unavailable extension API servers. ([#66932](https://github.com/kubernetes/kubernetes/pull/66932), [@nilebox](https://github.com/nilebox))

- Kubeadm: fixed a regression where the JoinConfiguration.discovery.timeout was no longer respected and the value was always hardcoded to "5m" (5 minutes). ([#125481](https://github.com/kubernetes/kubernetes/pull/125481), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

- Aggregated Discovery v2beta1 fixture is removed in `./api/discovery`. Please use v2 ([#127008](https://github.com/kubernetes/kubernetes/pull/127008), [@Jefftree](https://github.com/Jefftree)) [SIG API Machinery]

- `discovery.k8s.io/v1beta1` EndpointSlices are deprecated in favor of `discovery.k8s.io/v1`, and will no longer be served in Kubernetes v1.25. ([#100472](https://github.com/kubernetes/kubernetes/pull/100472), [@liggitt](https://github.com/liggitt))

- client-go discovery clients constructed using `NewDiscoveryClientForConfig` or `NewDiscoveryClientForConfigOrDie` default to rate limits that cause normal discovery request patterns to take several seconds. This is fixed in https://issue.k8s.io/86168 and will be resolved in v1.17.1. As a workaround, the `Burst` value can be adjusted higher...