Simplify webhook test

Author: mdbooth

pkg/webhooks/openstackcluster_webhook.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"reflect"
 
-	"k8s.io/apimachinery/pkg/api/equality"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	"k8s.io/utils/ptr"
@@ -201,15 +200,17 @@ func (*openStackClusterWebhook) ValidateUpdate(_ context.Context, oldObjRaw, new
 			allErrs = append(allErrs, field.Forbidden(field.NewPath("spec", "managedSubnets"), "cannot add or remove subnets"))
 		} else {
 			// Build maps of subnets by CIDR
-			oldSubnetMap := make(map[string]infrav1.SubnetSpec)
-			newSubnetMap := make(map[string]infrav1.SubnetSpec)
+			oldSubnetMap := make(map[string]*infrav1.SubnetSpec)
 
-			for _, subnet := range oldObj.Spec.ManagedSubnets {
-				oldSubnetMap[subnet.CIDR] = subnet
+			for i := range oldObj.Spec.ManagedSubnets {
+				oldSubnet := &oldObj.Spec.ManagedSubnets[i]
+				oldSubnetMap[oldSubnet.CIDR] = oldSubnet
 			}
 
 			// Check if all new subnets have matching old subnets with the same CIDR
-			for _, newSubnet := range newObj.Spec.ManagedSubnets {
+			for i := range newObj.Spec.ManagedSubnets {
+				newSubnet := &newObj.Spec.ManagedSubnets[i]
+
 				oldSubnet, exists := oldSubnetMap[newSubnet.CIDR]
 				if !exists {
 					allErrs = append(allErrs, field.Forbidden(
@@ -219,34 +220,10 @@ func (*openStackClusterWebhook) ValidateUpdate(_ context.Context, oldObjRaw, new
 					continue
 				}
 
-				// Check if AllocationPools have changed
-				if !equality.Semantic.DeepEqual(oldSubnet.AllocationPools, newSubnet.AllocationPools) {
-					allErrs = append(allErrs, field.Forbidden(
-						field.NewPath("spec", "managedSubnets").Child("allocationPools"),
-						"cannot modify allocation pools in existing subnet",
-					))
-				}
-
-				newSubnetMap[newSubnet.CIDR] = newSubnet
+				// DNSNameservers is mutable
+				oldSubnet.DNSNameservers = nil
+				newSubnet.DNSNameservers = nil
 			}
-
-			// Create modified copies of the subnets with DNSNameservers cleared
-			oldSubnets := make([]infrav1.SubnetSpec, 0, len(oldObj.Spec.ManagedSubnets))
-			newSubnets := make([]infrav1.SubnetSpec, 0, len(newObj.Spec.ManagedSubnets))
-			for _, subnet := range oldObj.Spec.ManagedSubnets {
-				subnetCopy := subnet
-				subnetCopy.DNSNameservers = nil
-				oldSubnets = append(oldSubnets, subnetCopy)
-
-				if newSubnet, exists := newSubnetMap[subnet.CIDR]; exists {
-					newSubnetCopy := newSubnet
-					newSubnetCopy.DNSNameservers = nil
-					newSubnets = append(newSubnets, newSubnetCopy)
-				}
-			}
-
-			oldObj.Spec.ManagedSubnets = oldSubnets
-			newObj.Spec.ManagedSubnets = newSubnets
 		}
 	}