OpenAPI specs for native types have long been served at /openapi/v2, and they are consumed by a number of components, notably kubectl client-side validation, kubectl explain and OpenAPI based client generators.

With Kubernetes 1.15 as beta, OpenAPI schemas are also published for CRDs, as long as their schemas are structural.

These changes are reflected in the following Kubernetes enhancements:

    * The `generate-internal-groups.sh` script in k8s.io/code-generator will generate OpenAPI definitions by default in `pkg/generated/openapi`. Additional API group dependencies can be added via `OPENAPI_EXTRA_PACKAGES=<group>/<version> <group2>/<version2>...`.