From 5038f80b45a881f9e601d1ee0776e772a5118332 Mon Sep 17 00:00:00 2001
From: Antoine Pelisse <apelisse@google.com>
Date: Tue, 12 Nov 2019 16:33:20 -0800
Subject: [PATCH] Strip nullable for Server-side apply

---
 .../pkg/apiserver/customresource_handler.go        |  2 +-
 .../pkg/apiserver/schema/skeleton.go               | 14 ++++++++++++++
 .../pkg/controller/openapi/builder/builder.go      |  6 ++++++
 test/integration/apiserver/apply/apply_crd_test.go |  3 ++-
 4 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go
index 8f21e2d9043..7f54d8396d3 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go
@@ -1245,7 +1245,7 @@ func buildOpenAPIModelsForApply(staticOpenAPISpec *spec.Swagger, crd *apiextensi
 
 	specs := []*spec.Swagger{}
 	for _, v := range crd.Spec.Versions {
-		s, err := builder.BuildSwagger(crd, v.Name, builder.Options{V2: false, StripDefaults: true, StripValueValidation: true, AllowNonStructural: true})
+		s, err := builder.BuildSwagger(crd, v.Name, builder.Options{V2: false, StripDefaults: true, StripValueValidation: true, StripNullable: true, AllowNonStructural: true})
 		if err != nil {
 			return nil, err
 		}
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/skeleton.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/skeleton.go
index ef1fa7808f7..550347adec0 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/skeleton.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/skeleton.go
@@ -49,3 +49,17 @@ func (s *Structural) StripValueValidations() *Structural {
 	v.Visit(s)
 	return s
 }
+
+// StripNullable returns a copy without nullable.
+func (s *Structural) StripNullable() *Structural {
+	s = s.DeepCopy()
+	v := Visitor{
+		Structural: func(s *Structural) bool {
+			changed := s.Nullable
+			s.Nullable = false
+			return changed
+		},
+	}
+	v.Visit(s)
+	return s
+}
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/controller/openapi/builder/builder.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/controller/openapi/builder/builder.go
index 8e71458ab6e..af8f0983d27 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/controller/openapi/builder/builder.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/controller/openapi/builder/builder.go
@@ -76,6 +76,9 @@ type Options struct {
 	// Strip value validation.
 	StripValueValidation bool
 
+	// Strip nullable.
+	StripNullable bool
+
 	// AllowNonStructural indicates swagger should be built for a schema that fits into the structural type but does not meet all structural invariants
 	AllowNonStructural bool
 }
@@ -101,6 +104,9 @@ func BuildSwagger(crd *apiextensions.CustomResourceDefinition, version string, o
 					if opts.StripValueValidation {
 						schema = schema.StripValueValidations()
 					}
+					if opts.StripNullable {
+						schema = schema.StripNullable()
+					}
 
 					schema = schema.Unfold()
 				}
diff --git a/test/integration/apiserver/apply/apply_crd_test.go b/test/integration/apiserver/apply/apply_crd_test.go
index 2e1bc1a91bb..2451136f38d 100644
--- a/test/integration/apiserver/apply/apply_crd_test.go
+++ b/test/integration/apiserver/apply/apply_crd_test.go
@@ -190,7 +190,8 @@ func TestApplyCRDStructuralSchema(t *testing.T) {
 										"type": "string"
 									},
 									"protocol": {
-										"type": "string"
+										"type": "string",
+										"nullable": true
 									}
 								},
 								"required": [