Move conditional validation for SCTPSupport to validation functions with knowledge of old objects

pkg/apis/networking/validation/conditional_validation.go

@@ -0,0 +1,59 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package validation
+
+import (
+	"k8s.io/apimachinery/pkg/util/validation/field"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	api "k8s.io/kubernetes/pkg/apis/core"
+	"k8s.io/kubernetes/pkg/apis/networking"
+	"k8s.io/kubernetes/pkg/features"
+)
+
+// ValidateConditionalNetworkPolicy validates conditionally valid fields.
+func ValidateConditionalNetworkPolicy(np, oldNP *networking.NetworkPolicy) field.ErrorList {
+	var errs field.ErrorList
+	// If the SCTPSupport feature is disabled, and the old object isn't using the SCTP feature, prevent the new object from using it
+	if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && len(sctpFields(oldNP)) == 0 {
+		for _, f := range sctpFields(np) {
+			errs = append(errs, field.NotSupported(f, api.ProtocolSCTP, []string{string(api.ProtocolTCP), string(api.ProtocolUDP)}))
+		}
+	}
+	return errs
+}
+
+func sctpFields(np *networking.NetworkPolicy) []*field.Path {
+	if np == nil {
+		return nil
+	}
+	fields := []*field.Path{}
+	for iIndex, e := range np.Spec.Ingress {
+		for pIndex, p := range e.Ports {
+			if p.Protocol != nil && *p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, field.NewPath("spec.ingress").Index(iIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	for eIndex, e := range np.Spec.Egress {
+		for pIndex, p := range e.Ports {
+			if p.Protocol != nil && *p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, field.NewPath("spec.egress").Index(eIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	return fields
+}