### 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

- Resolves a spurious "Unknown discovery response content-type" error in client-go discovery requests by tolerating extra content-type parameters in API responses ([#117571](https://github.com/kubernetes/kubernetes/pull/117571), [@seans3](https://github.com/seans3)) [SIG API Machinery]

	}

	// Configure an OpenID Connect aware OAuth2 client.
	oauth2Config := oauth2.Config{
		ClientID:     pro.ClientID,
		ClientSecret: pro.ClientSecret,
		RedirectURL:  pro.RedirectURL,

		// Discovery returns the OAuth2 endpoints.
		Endpoint: provider.Endpoint(),

		// "openid" is a required scope for OpenID Connect flows.
		Scopes: []string{oidc.ScopeOpenID, "groups"},
	}

- `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))

- 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]

- Fixed a regression in the default `v1.27` configurations in `kube-apiserver`: fixed the `AggregatedDiscoveryEndpoint` feature (`beta` in `v1.27+`) to successfully fetch discovery information from aggregated API servers that do not check `Accept` headers when serving the `/apis` endpoint. ([#119870](https://github.com/kubernetes/kubernetes/pull/119870), [@Jefftree](https://github.com/Jefftree))

- Increase default value of discovery cache TTL for kubectl to 6 hours. ([#107141](https://github.com/kubernetes/kubernetes/pull/107141), [@mk46](https://github.com/mk46))

- 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...

  
  ### Cluster API
  - Migrate interaction with the API from using internal types to using Unstructured
  - Improve tests to work better with constrained resources
  - Add support for node auto-discovery
  - Add support for `--cloud-config`
  - Update group identifier to use for Cluster API annotations
  
  ### Exoscale
  - Add support for Exoscale
  
  ### GCE

* Support struct,array,slice types when sorting kubectl output ([#25022](https://github.com/kubernetes/kubernetes/pull/25022), [@zhouhaibing089](https://github.com/zhouhaibing089))
* federated api servers: Adding a discovery summarizer server ([#20358](https://github.com/kubernetes/kubernetes/pull/20358), [@nikhiljindal](https://github.com/nikhiljindal))