vendor/k8s.io/kubernetes/staging/src/k8s.io/sample-controller/artifacts/examples/crd-validation.yaml

apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
  name: foos.samplecontroller.k8s.io
spec:
  group: samplecontroller.k8s.io
  version: v1alpha1
  names:
    kind: Foo
    plural: foos
  scope: Namespaced
  validation:
    openAPIV3Schema:
      properties:
        spec:
          properties:
            replicas:
              type: integer
              minimum: 1
              maximum: 10