- Removed container name from messages for container created and started events. ([#134043](https://github.com/kubernetes/kubernetes/pull/134043), [@HirazawaUi](https://github.com/HirazawaUi))
- Removed deprecated gogo protocol definitions from `k8s.io/kubelet/pkg/apis/dra` in favor of `google.golang.org/protobuf`. ([#133026](https://github.com/kubernetes/kubernetes/pull/133026), [@saschagrunert](https://github.com/saschagrunert)) [SIG API Machinery and Node]

* Validation et documentation via ces types.
* Système d'injection de dépendances.

Il n'utilise pas une librairie tiers de validation, sérialisation et de documentation tel que Pydantic, il utilise son propre système. Ainsi, ces définitions de types de données ne sont pas réutilisables aussi facilement.

Il nécessite une configuration un peu plus verbeuse. Et comme il est basé sur WSGI (au lieu d'ASGI), il n'est pas

* CustomResourceDefinitions: OpenAPI v3 validation schemas containing `$ref`references are no longer permitted. Before upgrading, ensure CRD definitions do not include those `$ref` fields. ([#58438](https://github.com/kubernetes/kubernetes/pull/58438), [@carlory](https://github.com/carlory))

  - The OpenAPI definitions with the prefix "io.k8s.kubernetes.pkg" (deprecated since 1.9) have been removed. ([#74596](https://github.com/kubernetes/kubernetes/pull/74596), [@sttts](https://github.com/sttts))

- Restores compatibility with <=1.15.x custom resources by not publishing OpenAPI for non-structural custom resource definitions ([#82653](https://github.com/kubernetes/kubernetes/pull/82653), [@liggitt](https://github.com/liggitt))

- Ingress:
  - `spec.ingressClassName` replaces the deprecated `kubernetes.io/ingress.class` annotation, and allows associating an Ingress object with a particular controller.

* CustomResourceDefinitions: OpenAPI v3 validation schemas containing `$ref`references are no longer permitted (valid references could not be constructed previously because property ids were not permitted either). Before upgrading, ensure CRD definitions do not include those `$ref` fields. ([#58438](https://github.com/kubernetes/kubernetes/pull/58438), [@carlory](https://github.com/carlory))

- The `batch/v2alpha1` CronJob type definitions and clients are deprecated and removed. ([#96987](https://github.com/kubernetes/kubernetes/pull/96987), [@soltysh](https://github.com/soltysh)) [SIG API Machinery, Apps, CLI and Testing]

- Validation rules for Custom Resource Definitions can be written in the [CEL expression language](https://github.com/google/cel-spec) using the `x-kubernetes-validations` extension in OpenAPIv3 schemas (alpha). This is gated by the alpha "CustomResourceValidationExpressions" feature gate. ([#1...

- Fixed a regression in `1.27.0` that resulted in `missing metadata in converted object` errors when modifying objects for multi-version custom resource definitions with a conversion strategy of `None`. ([#117301](https://github.com/kubernetes/kubernetes/pull/117301), [@ncdc](https://github.com/ncdc))