filter entries by kind in name

pkg/dns/source/controller.go

@@ -91,7 +91,7 @@ func DNSSourceController(source DNSSourceType, reconcilerType controller.Reconci
 		Cluster(cluster.DEFAULT). // first one used as MAIN cluster
 		DefaultWorkerPool(2, 120*time.Second).
 		MainResource(gk.Group, gk.Kind).
-		Reconciler(reconcilers.SlaveReconcilerTypeByFunction(SlaveReconcilerType, SlaveAccessSpecCreatorForSource(source)), "entries").
+		Reconciler(reconcilerTypeFilterByKind(gk.Kind, reconcilers.SlaveReconcilerTypeByFunction(SlaveReconcilerType, SlaveAccessSpecCreatorForSource(source))), "entries").
 		Reconciler(OwnerReconciler, "owner").
 		Cluster(TARGET_CLUSTER, cluster.DEFAULT).
 		CustomResourceDefinitions(entryGroupKind).

pkg/dns/source/filterbykindreonciler.go

@@ -0,0 +1,91 @@
+// SPDX-FileCopyrightText: 2025 SAP SE or an SAP affiliate company and Gardener contributors
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package source
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/gardener/controller-manager-library/pkg/controllermanager/controller"
+	"github.com/gardener/controller-manager-library/pkg/controllermanager/controller/reconcile"
+	"github.com/gardener/controller-manager-library/pkg/logger"
+	"github.com/gardener/controller-manager-library/pkg/resources"
+)
+
+func reconcilerTypeFilterByKind(kind string, reconcilerType controller.ReconcilerType) controller.ReconcilerType {
+	return func(c controller.Interface) (reconcile.Interface, error) {
+		reconciler, err := reconcilerType(c)
+		if err != nil {
+			return nil, err
+		}
+		return &filterByKindReconciler{
+			nested:        reconciler,
+			kindSubstring: fmt.Sprintf("-%s-", strings.ToLower(kind)),
+		}, nil
+	}
+}
+
+// filterByKindReconciler is a reconciler that filters out entries by kind.
+type filterByKindReconciler struct {
+	nested        reconcile.Interface
+	kindSubstring string
+}
+
+var _ reconcile.Interface = &filterByKindReconciler{}
+var _ reconcile.StartInterface = &filterByKindReconciler{}
+var _ reconcile.SetupInterface = &filterByKindReconciler{}
+var _ reconcile.CleanupInterface = &filterByKindReconciler{}
+
+func (f filterByKindReconciler) Start() error {
+	if itf, ok := f.nested.(reconcile.StartInterface); ok {
+		return itf.Start()
+	}
+	return nil
+}
+
+func (f filterByKindReconciler) Setup() error {
+	if itf, ok := f.nested.(reconcile.SetupInterface); ok {
+		return itf.Setup()
+	}
+	return nil
+}
+
+func (f filterByKindReconciler) Cleanup() error {
+	if itf, ok := f.nested.(reconcile.CleanupInterface); ok {
+		return itf.Cleanup()
+	}
+	return nil
+}
+
+func (f filterByKindReconciler) Reconcile(logger logger.LogContext, object resources.Object) reconcile.Status {
+	if !f.isRelevantByHeuristic(object.GetName()) {
+		return reconcile.Succeeded(logger)
+	}
+	return f.nested.Reconcile(logger, object)
+}
+
+func (f filterByKindReconciler) Delete(logger logger.LogContext, object resources.Object) reconcile.Status {
+	if !f.isRelevantByHeuristic(object.GetName()) {
+		return reconcile.Succeeded(logger)
+	}
+	return f.nested.Delete(logger, object)
+}
+
+func (f filterByKindReconciler) Deleted(logger logger.LogContext, key resources.ClusterObjectKey) reconcile.Status {
+	if !f.isRelevantByHeuristic(key.Name()) {
+		return reconcile.Succeeded(logger)
+	}
+	return f.nested.Deleted(logger, key)
+}
+
+func (f filterByKindReconciler) Command(logger logger.LogContext, cmd string) reconcile.Status {
+	return f.nested.Command(logger, cmd)
+}
+
+// isRelevantByHeuristic returns true if the entry name contains the kind substring.
+// This is a heuristic which relies on the fact that the SourceReconciler adds the kind to the entry name.
+func (this *filterByKindReconciler) isRelevantByHeuristic(objectName string) bool {
+	return strings.Contains(objectName, this.kindSubstring)
+}