- update to 12.0.1:
* Kubernetes API version 1.16.15
- Resolve regression in metadata.managedFields handling in update/patch requests submitted by older API clients ([#91748](https://github.com/kubernetes/k
ubernetes/pull/91748), [@apelisse](https://github.com/apelisse)) [SIG API Machinery and Testing]
- Fix bug where sending a status update completely wipes managedFields for some types. ([#90033](https://github.com/kubernetes/kubernetes/pull/90033), [@
apelisse](https://github.com/apelisse)) [SIG API Machinery and Testing]
- The `MutatingWebhookConfiguration` and `ValidatingWebhookConfiguration` APIs have been promoted to `admissionregistration.k8s.io/v1`:
- `failurePolicy` default changed from `Ignore` to `Fail` for v1
- `matchPolicy` default changed from `Exact` to `Equivalent` for v1
- `timeout` default changed from `30s` to `10s` for v1
- `sideEffects` default value is removed, and the field made required, and only `None` and `NoneOnDryRun` are permitted for v1
- `admissionReviewVersions` default value is removed and the field made required for v1 (supported versions for AdmissionReview are `v1` and `v1beta1`)
- The `name` field for specified webhooks must be unique for `MutatingWebhookConfiguration` and `ValidatingWebhookConfiguration` objects created via `a
dmissionregistration.k8s.io/v1`
- The `AdmissionReview` API sent to and received from admission webhooks has been promoted to `admission.k8s.io/v1`. Webhooks can specify a preference fo
r receiving `v1` AdmissionReview objects with `admissionReviewVersions: ["v1","v1beta1"]`, and must respond with an API object in the same `apiVersion` t
hey are sent. When webhooks use `admission.k8s.io/v1`, the following additional validation is performed on their responses:
- `response.patch` and `response.patchType` are not permitted from validating admission webhooks
- `apiVersion: "admission.k8s.io/v1"` is required
- `kind: "AdmissionReview"` is required
- `response.uid: ""` is required
- `response.patchType: "JSONPatch"` is required (if `response.patch` is set) ([#80231](https://github.com/kubernetes/kubernetes/pull/80231), [@liggitt]
(https://github.com/liggitt))
- The `CustomResourceDefinition` API type is promoted to `apiextensions.k8s.io/v1` with the following changes:
- Use of the new `default` feature in validation schemas is limited to v1
- `spec.scope` is no longer defaulted to `Namespaced` and must be explicitly specified
- `spec.version` is removed in v1; use `spec.versions` instead
- `spec.validation` is removed in v1; use `spec.versions[*].schema` instead
- `spec.subresources` is removed in v1; use `spec.versions[*].subresources` instead
- `spec.additionalPrinterColumns` is removed in v1; use `spec.versions[*].additionalPrinterColumns` instead