Extend Deployment/Pool builtin to include metadata

This patch extends the MachineDeployment and MachinePool builtins to
include metadata.

Signed-off-by: Sagar Muchhal <muchhals@vmware.com>

docs/book/src/tasks/experimental-features/cluster-class/write-clusterclass.md

@@ -542,13 +542,13 @@ referenced in patches:
 - `builtin.controlPlane.machineTemplate.infrastructureRef.name`
     - Please note, these variables are only available when using a control plane with machines and 
       when patching control plane or control plane machine templates.
-- `builtin.machineDeployment.{replicas,version,class,name,topologyName}`
+- `builtin.machineDeployment.{replicas,version,class,name,topologyName,metadata.labels,metadata.annotations}`
     - Please note, these variables are only available when patching the templates of a MachineDeployment 
       and contain the values of the current `MachineDeployment` topology.
 - `builtin.machineDeployment.{infrastructureRef.name,bootstrap.configRef.name}`
     - Please note, these variables are only available when patching the templates of a MachineDeployment
       and contain the values of the current `MachineDeployment` topology.
-- `builtin.machinePool.{replicas,version,class,name,topologyName}`
+- `builtin.machinePool.{replicas,version,class,name,topologyName,metadata.labels,metadata.annotations}`
     - Please note, these variables are only available when patching the templates of a MachinePool 
       and contain the values of the current `MachinePool` topology.
 - `builtin.machinePool.{infrastructureRef.name,bootstrap.configRef.name}`

exp/runtime/hooks/api/v1alpha1/topologymutation_variable_types.go

@@ -16,7 +16,11 @@ limitations under the License.
 
 package v1alpha1
 
-import "k8s.io/apimachinery/pkg/types"
+import (
+	"k8s.io/apimachinery/pkg/types"
+
+	clusterv1 "sigs.k8s.io/cluster-api/api/v1beta1"
+)
 
 // BuiltinsName is the name of the builtin variable.
 const BuiltinsName = "builtin"
@@ -116,6 +120,9 @@ type MachineDeploymentBuiltins struct {
 	// being orchestrated.
 	Version string `json:"version,omitempty"`
 
+	// Metadata is the additional metadata set on the MachineDeployment
+	Metadata *clusterv1.ObjectMeta `json:"metadata,omitempty"`
+
 	// Class is the class name of the MachineDeployment,
 	// to which the current template belongs to.
 	Class string `json:"class,omitempty"`
@@ -149,6 +156,9 @@ type MachinePoolBuiltins struct {
 	// being orchestrated.
 	Version string `json:"version,omitempty"`
 
+	// Metadata is the additional metadata set on the MachinePool.
+	Metadata *clusterv1.ObjectMeta `json:"metadata,omitempty"`
+
 	// Class is the class name of the MachinePool,
 	// to which the current template belongs to.
 	Class string `json:"class,omitempty"`

internal/controllers/topology/cluster/patches/engine_test.go

@@ -1139,7 +1139,7 @@ func setupTestObjects() (*scope.ClusterBlueprint, *scope.ClusterState) {
 				Workers: &clusterv1.WorkersTopology{
 					MachineDeployments: []clusterv1.MachineDeploymentTopology{
 						{
-							Metadata: clusterv1.ObjectMeta{},
+							Metadata: clusterv1.ObjectMeta{Labels: map[string]string{"foo": "bar"}, Annotations: map[string]string{"fizz": "buzz"}},
 							Class:    "default-worker",
 							Name:     "default-worker-topo1",
 							Variables: &clusterv1.MachineDeploymentVariables{
@@ -1161,7 +1161,7 @@ func setupTestObjects() (*scope.ClusterBlueprint, *scope.ClusterState) {
 					},
 					MachinePools: []clusterv1.MachinePoolTopology{
 						{
-							Metadata: clusterv1.ObjectMeta{},
+							Metadata: clusterv1.ObjectMeta{Labels: map[string]string{"foo": "bar"}, Annotations: map[string]string{"fizz": "buzz"}},
 							Class:    "default-mp-worker",
 							Name:     "default-mp-worker-topo1",
 							Variables: &clusterv1.MachinePoolVariables{

internal/controllers/topology/cluster/patches/variables/variables.go

@@ -182,6 +182,12 @@ func MachineDeployment(mdTopology *clusterv1.MachineDeploymentTopology, md *clus
 	if md.Spec.Replicas != nil {
 		builtin.MachineDeployment.Replicas = ptr.To[int64](int64(*md.Spec.Replicas))
 	}
+	if md.Labels != nil || md.Annotations != nil {
+		builtin.MachineDeployment.Metadata = &clusterv1.ObjectMeta{
+			Annotations: md.Annotations,
+			Labels:      md.Labels,
+		}
+	}
 
 	if mdBootstrapTemplate != nil {
 		builtin.MachineDeployment.Bootstrap = &runtimehooksv1.MachineBootstrapBuiltins{
@@ -235,6 +241,12 @@ func MachinePool(mpTopology *clusterv1.MachinePoolTopology, mp *expv1.MachinePoo
 	if mp.Spec.Replicas != nil {
 		builtin.MachinePool.Replicas = ptr.To[int64](int64(*mp.Spec.Replicas))
 	}
+	if mp.Labels != nil || mp.Annotations != nil {
+		builtin.MachinePool.Metadata = &clusterv1.ObjectMeta{
+			Annotations: mp.Annotations,
+			Labels:      mp.Labels,
+		}
+	}
 
 	if mpBootstrapObject != nil {
 		builtin.MachinePool.Bootstrap = &runtimehooksv1.MachineBootstrapBuiltins{

internal/controllers/topology/cluster/patches/variables/variables_test.go

@@ -684,6 +684,8 @@ func TestMachineDeployment(t *testing.T) {
 			md: builder.MachineDeployment(metav1.NamespaceDefault, "md1").
 				WithReplicas(3).
 				WithVersion("v1.21.1").
+				WithLabels(map[string]string{"foo": "bar"}).
+				WithAnnotations(map[string]string{"fizz": "buzz"}).
 				Build(),
 			want: []runtimehooksv1.Variable{
 				{
@@ -699,6 +701,7 @@ func TestMachineDeployment(t *testing.T) {
 					Value: toJSONCompact(`{
 					"machineDeployment":{
 						"version": "v1.21.1",
+						"metadata": {"labels":{"foo":"bar"}, "annotations":{"fizz":"buzz"}},
 						"class": "md-class",
 						"name": "md1",
 						"topologyName": "md-topology",
@@ -1051,6 +1054,8 @@ func TestMachinePool(t *testing.T) {
 			mp: builder.MachinePool(metav1.NamespaceDefault, "mp1").
 				WithReplicas(3).
 				WithVersion("v1.21.1").
+				WithLabels(map[string]string{"foo": "bar"}).
+				WithAnnotations(map[string]string{"fizz": "buzz"}).
 				Build(),
 			want: []runtimehooksv1.Variable{
 				{
@@ -1066,6 +1071,7 @@ func TestMachinePool(t *testing.T) {
 					Value: toJSONCompact(`{
 					"machinePool":{
 						"version": "v1.21.1",
+						"metadata": {"labels":{"foo":"bar"}, "annotations":{"fizz":"buzz"}},
 						"class": "mp-class",
 						"name": "mp1",
 						"topologyName": "mp-topology",

internal/test/builder/builders.go

@@ -1540,6 +1540,7 @@ type MachinePoolBuilder struct {
 	clusterName     string
 	replicas        *int32
 	labels          map[string]string
+	annotations     map[string]string
 	status          *expv1.MachinePoolStatus
 	minReadySeconds *int32
 }
@@ -1570,6 +1571,12 @@ func (m *MachinePoolBuilder) WithLabels(labels map[string]string) *MachinePoolBu
 	return m
 }
 
+// WithAnnotations adds the given annotations to the MachinePoolBuilder.
+func (m *MachinePoolBuilder) WithAnnotations(annotations map[string]string) *MachinePoolBuilder {
+	m.annotations = annotations
+	return m
+}
+
 // WithVersion sets the passed version on the MachinePool spec.
 func (m *MachinePoolBuilder) WithVersion(version string) *MachinePoolBuilder {
 	m.version = &version
@@ -1608,9 +1615,10 @@ func (m *MachinePoolBuilder) Build() *expv1.MachinePool {
 			APIVersion: expv1.GroupVersion.String(),
 		},
 		ObjectMeta: metav1.ObjectMeta{
-			Name:      m.name,
-			Namespace: m.namespace,
-			Labels:    m.labels,
+			Name:        m.name,
+			Namespace:   m.namespace,
+			Labels:      m.labels,
+			Annotations: m.annotations,
 		},
 		Spec: expv1.MachinePoolSpec{
 			ClusterName:     m.clusterName,
@@ -1648,6 +1656,7 @@ type MachineDeploymentBuilder struct {
 	replicas               *int32
 	generation             *int64
 	labels                 map[string]string
+	annotations            map[string]string
 	status                 *clusterv1.MachineDeploymentStatus
 	minReadySeconds        *int32
 }
@@ -1690,6 +1699,11 @@ func (m *MachineDeploymentBuilder) WithLabels(labels map[string]string) *Machine
 	return m
 }
 
+func (m *MachineDeploymentBuilder) WithAnnotations(annotations map[string]string) *MachineDeploymentBuilder {
+	m.annotations = annotations
+	return m
+}
+
 // WithVersion sets the passed version on the machine deployment spec.
 func (m *MachineDeploymentBuilder) WithVersion(version string) *MachineDeploymentBuilder {
 	m.version = &version
@@ -1728,9 +1742,10 @@ func (m *MachineDeploymentBuilder) Build() *clusterv1.MachineDeployment {
 			APIVersion: clusterv1.GroupVersion.String(),
 		},
 		ObjectMeta: metav1.ObjectMeta{
-			Name:      m.name,
-			Namespace: m.namespace,
-			Labels:    m.labels,
+			Name:        m.name,
+			Namespace:   m.namespace,
+			Labels:      m.labels,
+			Annotations: m.annotations,
 		},
 	}
 	if m.generation != nil {

internal/webhooks/patch_validation.go

@@ -500,6 +500,8 @@ var builtinVariables = sets.Set[string]{}.Insert(
 	"builtin.machineDeployment.replicas",
 	"builtin.machineDeployment.topologyName",
 	"builtin.machineDeployment.version",
+	"builtin.machineDeployment.metadata.labels",
+	"builtin.machineDeployment.metadata.annotations",
 	// MachineDeployment ref builtins.
 	"builtin.machineDeployment.bootstrap.configRef.name",
 	"builtin.machineDeployment.infrastructureRef.name",
@@ -511,6 +513,8 @@ var builtinVariables = sets.Set[string]{}.Insert(
 	"builtin.machinePool.replicas",
 	"builtin.machinePool.topologyName",
 	"builtin.machinePool.version",
+	"builtin.machinePool.metadata.labels",
+	"builtin.machinePool.metadata.annotations",
 	// MachinePool ref builtins.
 	"builtin.machinePool.bootstrap.configRef.name",
 	"builtin.machinePool.infrastructureRef.name",