MON-4432: Migrate windows-exporter ServiceMonitor to EndpointSlice

Update ServiceMonitor configuration to use EndpointSlice discovery
instead of Endpoints API for improved scalability.

- Set serviceDiscoveryRole to EndpointSlice
- Update relabel metadata label for EndpointSlice
- Add endpointslices RBAC permissions

Signed-off-by: Jayapriya Pai <[email protected]>
Assisted-By: Cursor AI

Author: slashpai

bundle/manifests/prometheus-k8s_rbac.authorization.k8s.io_v1_role.yaml

@@ -13,3 +13,11 @@ rules:
   verbs:
   - list
   - watch
+- apiGroups:
+  - "discovery.k8s.io"
+  resources:
+  - endpointslices
+  verbs:
+  - get
+  - list
+  - watch

config/windows-exporter/windows-exporter-role.yaml

@@ -13,3 +13,11 @@ rules:
     verbs:
       - list
       - watch
+  - apiGroups:
+      - "discovery.k8s.io"
+    resources:
+      - endpointslices
+    verbs:
+      - get
+      - list
+      - watch

controllers/metric_controller.go

@@ -8,7 +8,7 @@ import (
 
 	monv1 "github.com/prometheus-operator/prometheus-operator/pkg/apis/monitoring/v1"
 	monclient "github.com/prometheus-operator/prometheus-operator/pkg/client/versioned/typed/monitoring/v1"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -132,6 +132,7 @@ func (r *metricReconciler) ensureServiceMonitor(ctx context.Context) error {
 	replacement1 := "$1:9182"
 	replacement2 := metrics.WindowsMetricsResource
 	attachMetadataBool := true
+	endpointSliceRole := monv1.EndpointSliceRole
 	expectedSM := &monv1.ServiceMonitor{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      metrics.WindowsMetricsResource,
@@ -141,6 +142,7 @@ func (r *metricReconciler) ensureServiceMonitor(ctx context.Context) error {
 			},
 		},
 		Spec: monv1.ServiceMonitorSpec{
+			ServiceDiscoveryRole: &endpointSliceRole,
 			AttachMetadata: &monv1.AttachMetadata{
 				Node: &attachMetadataBool,
 			},
@@ -165,7 +167,7 @@ func (r *metricReconciler) ensureServiceMonitor(ctx context.Context) error {
 							Replacement: &replacement0,
 							TargetLabel: "instance",
 							SourceLabels: []monv1.LabelName{
-								"__meta_kubernetes_endpoint_address_target_name",
+								"__meta_kubernetes_endpointslice_endpoint_target_name",
 							},
 						},
 						{ // Include only Windows nodes for this serviceMonitor