Hide OpeAPI details behind the NewTypeConverter

The fact that we're building the OpenAPI using the proto.Models is an
implementation detail that we shouldn't have to expose. Since we're
going to change the way this is transformed, let's first hide it behind
the common NewTypeConverter so that the next change is transparent.

This will also enable other clean-ups like hiding the gvkParser which
shouldn't be exposed and prevent some refactoring.

Kubernetes-commit: a7ab6b86db83e31ff599e4d21a065f6845fb93dd

Author: apelisse

pkg/apiserver/customresource_handler.go

@@ -71,13 +71,11 @@ import (
 	apirequest "k8s.io/apiserver/pkg/endpoints/request"
 	"k8s.io/apiserver/pkg/registry/generic"
 	genericfilters "k8s.io/apiserver/pkg/server/filters"
-	utilopenapi "k8s.io/apiserver/pkg/util/openapi"
 	"k8s.io/apiserver/pkg/warning"
 	"k8s.io/client-go/scale"
 	"k8s.io/client-go/scale/scheme/autoscalingv1"
 	"k8s.io/client-go/tools/cache"
 	"k8s.io/klog/v2"
-	"k8s.io/kube-openapi/pkg/util/proto"
 	"k8s.io/kube-openapi/pkg/validation/spec"
 	"k8s.io/kube-openapi/pkg/validation/strfmt"
 	"k8s.io/kube-openapi/pkg/validation/validate"
@@ -1371,7 +1369,7 @@ func hasServedCRDVersion(spec *apiextensionsv1.CustomResourceDefinitionSpec, ver
 // buildOpenAPIModelsForApply constructs openapi models from any validation schemas specified in the custom resource,
 // and merges it with the models defined in the static OpenAPI spec.
 // Returns nil models ifthe static spec is nil, or an error is encountered.
-func buildOpenAPIModelsForApply(staticOpenAPISpec *spec.Swagger, crd *apiextensionsv1.CustomResourceDefinition) (proto.Models, error) {
+func buildOpenAPIModelsForApply(staticOpenAPISpec *spec.Swagger, crd *apiextensionsv1.CustomResourceDefinition) (*spec.Swagger, error) {
 	if staticOpenAPISpec == nil {
 		return nil, nil
 	}
@@ -1391,9 +1389,5 @@ func buildOpenAPIModelsForApply(staticOpenAPISpec *spec.Swagger, crd *apiextensi
 	if err != nil {
 		return nil, err
 	}
-	models, err := utilopenapi.ToProtoModels(mergedOpenAPI)
-	if err != nil {
-		return nil, err
-	}
-	return models, nil
+	return mergedOpenAPI, nil
 }