Fix FailoverIP validation and immutability tests

- Update FailoverIP validation rule to handle optional fields correctly
  - Add !has(self) check for optional field handling
  - Improve IPv4 regex pattern for more accurate validation
  - Fixes validation for 'Auto' (mixed case) and incomplete IPs

- Fix FailoverIP immutability test
  - Add Get calls before Update attempts to ensure CEL validation
    can properly compare self with oldSelf
  - Same fix pattern as DatacenterID immutability test

Author: schegi

api/v1alpha1/ionoscloudmachine_types.go

@@ -164,7 +164,7 @@ type IonosCloudMachineSpec struct {
 	//
 	// If the machine is a control plane machine, this field will not be taken into account.
 	//+kubebuilder:validation:XValidation:rule="self == oldSelf",message="failoverIP is immutable"
-	//+kubebuilder:validation:XValidation:rule=`self == "AUTO" || self.matches("((25[0-5]|(2[0-4]|1\\d|[1-9]|)\\d)\\.?\\b){4}$")`,message="failoverIP must be either 'AUTO' or a valid IPv4 address"
+	//+kubebuilder:validation:XValidation:rule=`!has(self) || self == "AUTO" || self.matches("^((25[0-5]|(2[0-4]|1[0-9]|[1-9])?[0-9])\\.){3}(25[0-5]|(2[0-4]|1[0-9]|[1-9])?[0-9])$")`,message="failoverIP must be either 'AUTO' or a valid IPv4 address"
 	//+optional
 	FailoverIP *string `json:"failoverIP,omitempty"`
 

api/v1alpha1/ionoscloudmachine_types_test.go

@@ -463,8 +463,12 @@ var _ = Describe("IonosCloudMachine Tests", func() {
 			m.Spec.FailoverIP = ptr.To(CloudResourceConfigAuto)
 			Expect(k8sClient.Create(context.Background(), m)).To(Succeed())
 			Expect(m.Spec.FailoverIP).To(Equal(ptr.To(CloudResourceConfigAuto)))
+			// Get the object from the server to ensure we have the latest version
+			Expect(k8sClient.Get(context.Background(), client.ObjectKey{Name: m.Name, Namespace: m.Namespace}, m)).To(Succeed())
 			m.Spec.FailoverIP = ptr.To("127.0.0.1")
 			Expect(k8sClient.Update(context.Background(), m)).ToNot(Succeed())
+			// Get the object again before the next update attempt
+			Expect(k8sClient.Get(context.Background(), client.ObjectKey{Name: m.Name, Namespace: m.Namespace}, m)).To(Succeed())
 			m.Spec.FailoverIP = ptr.To("")
 			Expect(k8sClient.Update(context.Background(), m)).ToNot(Succeed())
 		})

config/crd/bases/infrastructure.cluster.x-k8s.io_ionoscloudmachines.yaml

@@ -260,7 +260,7 @@ spec:
                 - message: failoverIP is immutable
                   rule: self == oldSelf
                 - message: failoverIP must be either 'AUTO' or a valid IPv4 address
-                  rule: self == "AUTO" || self.matches("((25[0-5]|(2[0-4]|1\\d|[1-9]|)\\d)\\.?\\b){4}$")
+                  rule: '!has(self) || self == "AUTO" || self.matches("^((25[0-5]|(2[0-4]|1[0-9]|[1-9])?[0-9])\\.){3}(25[0-5]|(2[0-4]|1[0-9]|[1-9])?[0-9])$")'
               ipv4PoolRef:
                 description: |-
                   IPv4PoolRef is a reference to an IPAMConfig Pool resource, which exposes IPv4 addresses.