RFC: Generic Reconciler for Bricks

This change shows an example of how a generic reconciler to be used for
bricks could look like.

Author: felix-kaestner

api/v1alpha1/acl_types.go

@@ -142,6 +142,18 @@ func (acl *AccessControlList) SetConditions(conditions []metav1.Condition) {
 	acl.Status.Conditions = conditions
 }
 
+func (acl *AccessControlList) GetDeviceRef() LocalObjectReference {
+	return acl.Spec.DeviceRef
+}
+
+func (acl *AccessControlList) GetProviderConfigRef() *TypedLocalObjectReference {
+	return acl.Spec.ProviderConfigRef
+}
+
+func (acl *AccessControlList) GetStatus() any {
+	return acl.Status
+}
+
 // +kubebuilder:object:root=true
 
 // AccessControlListList contains a list of AccessControlList

internal/controller/acl_controller.go

@@ -7,9 +7,6 @@ import (
 	"context"
 	"fmt"
 
-	"k8s.io/apimachinery/pkg/api/equality"
-	apierrors "k8s.io/apimachinery/pkg/api/errors"
-	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	kerrors "k8s.io/apimachinery/pkg/util/errors"
@@ -21,7 +18,6 @@ import (
 
 	"github.com/ironcore-dev/network-operator/api/v1alpha1"
 	"github.com/ironcore-dev/network-operator/internal/conditions"
-	"github.com/ironcore-dev/network-operator/internal/deviceutil"
 	"github.com/ironcore-dev/network-operator/internal/provider"
 )
 
@@ -46,129 +42,6 @@ type AccessControlListReconciler struct {
 // +kubebuilder:rbac:groups=networking.cloud.sap,resources=accesscontrollists/finalizers,verbs=update
 // +kubebuilder:rbac:groups=core,resources=events,verbs=create;patch
 
-// Reconcile is part of the main kubernetes reconciliation loop which aims to
-// move the current state of the cluster closer to the desired state.
-//
-// For more details, check Reconcile and its Result here:
-// - https://pkg.go.dev/sigs.k8s.io/[email protected]/pkg/reconcile
-//
-// For more details about the method shape, read up here:
-// - https://ahmet.im/blog/controller-pitfalls/#reconcile-method-shape
-func (r *AccessControlListReconciler) Reconcile(ctx context.Context, req ctrl.Request) (_ ctrl.Result, reterr error) {
-	log := ctrl.LoggerFrom(ctx)
-	log.Info("Reconciling resource")
-
-	obj := new(v1alpha1.AccessControlList)
-	if err := r.Get(ctx, req.NamespacedName, obj); err != nil {
-		if apierrors.IsNotFound(err) {
-			// If the custom resource is not found then it usually means that it was deleted or not created
-			// In this way, we will stop the reconciliation
-			log.Info("Resource not found. Ignoring since object must be deleted")
-			return ctrl.Result{}, nil
-		}
-		// Error reading the object - requeue the request.
-		log.Error(err, "Failed to get resource")
-		return ctrl.Result{}, err
-	}
-
-	prov, ok := r.Provider().(provider.ACLProvider)
-	if !ok {
-		if meta.SetStatusCondition(&obj.Status.Conditions, metav1.Condition{
-			Type:    v1alpha1.ReadyCondition,
-			Status:  metav1.ConditionFalse,
-			Reason:  v1alpha1.NotImplementedReason,
-			Message: "Provider does not implement provider.AccessControlListProvider",
-		}) {
-			return ctrl.Result{}, r.Status().Update(ctx, obj)
-		}
-		return ctrl.Result{}, nil
-	}
-
-	device, err := deviceutil.GetDeviceByName(ctx, r, obj.Namespace, obj.Spec.DeviceRef.Name)
-	if err != nil {
-		return ctrl.Result{}, err
-	}
-
-	conn, err := deviceutil.GetDeviceConnection(ctx, r, device)
-	if err != nil {
-		return ctrl.Result{}, err
-	}
-
-	var cfg *provider.ProviderConfig
-	if obj.Spec.ProviderConfigRef != nil {
-		cfg, err = provider.GetProviderConfig(ctx, r, obj.Namespace, obj.Spec.ProviderConfigRef)
-		if err != nil {
-			return ctrl.Result{}, err
-		}
-	}
-
-	s := &aclScope{
-		Device:         device,
-		ACL:            obj,
-		Connection:     conn,
-		ProviderConfig: cfg,
-		Provider:       prov,
-	}
-
-	if !obj.DeletionTimestamp.IsZero() {
-		if controllerutil.ContainsFinalizer(obj, v1alpha1.FinalizerName) {
-			if err := r.finalize(ctx, s); err != nil {
-				log.Error(err, "Failed to finalize resource")
-				return ctrl.Result{}, err
-			}
-			controllerutil.RemoveFinalizer(obj, v1alpha1.FinalizerName)
-			if err := r.Update(ctx, obj); err != nil {
-				log.Error(err, "Failed to remove finalizer from resource")
-				return ctrl.Result{}, err
-			}
-		}
-		log.Info("Resource is being deleted, skipping reconciliation")
-		return ctrl.Result{}, nil
-	}
-
-	// More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/finalizers
-	if !controllerutil.ContainsFinalizer(obj, v1alpha1.FinalizerName) {
-		controllerutil.AddFinalizer(obj, v1alpha1.FinalizerName)
-		if err := r.Update(ctx, obj); err != nil {
-			log.Error(err, "Failed to add finalizer to resource")
-			return ctrl.Result{}, err
-		}
-		log.Info("Added finalizer to resource")
-		return ctrl.Result{}, nil
-	}
-
-	orig := obj.DeepCopy()
-	if conditions.InitializeConditions(obj, v1alpha1.ReadyCondition) {
-		log.Info("Initializing status conditions")
-		return ctrl.Result{}, r.Status().Update(ctx, obj)
-	}
-
-	// Always attempt to update the metadata/status after reconciliation
-	defer func() {
-		if !equality.Semantic.DeepEqual(orig.ObjectMeta, obj.ObjectMeta) {
-			if err := r.Patch(ctx, obj, client.MergeFrom(orig)); err != nil {
-				log.Error(err, "Failed to update resource metadata")
-				reterr = kerrors.NewAggregate([]error{reterr, err})
-			}
-			return
-		}
-
-		if !equality.Semantic.DeepEqual(orig.Status, obj.Status) {
-			if err := r.Status().Patch(ctx, obj, client.MergeFrom(orig)); err != nil {
-				log.Error(err, "Failed to update status")
-				reterr = kerrors.NewAggregate([]error{reterr, err})
-			}
-		}
-	}()
-
-	if err := r.reconcile(ctx, s); err != nil {
-		log.Error(err, "Failed to reconcile resource")
-		return ctrl.Result{}, err
-	}
-
-	return ctrl.Result{}, nil
-}
-
 // SetupWithManager sets up the controller with the Manager.
 func (r *AccessControlListReconciler) SetupWithManager(mgr ctrl.Manager) error {
 	labelSelector := metav1.LabelSelector{}
@@ -181,32 +54,24 @@ func (r *AccessControlListReconciler) SetupWithManager(mgr ctrl.Manager) error {
 		return fmt.Errorf("failed to create label selector predicate: %w", err)
 	}
 
+	rec := AsReconciler(r.Client, r.Provider, r)
 	return ctrl.NewControllerManagedBy(mgr).
 		For(&v1alpha1.AccessControlList{}).
 		Named("accesscontrollist").
 		WithEventFilter(filter).
-		Complete(r)
-}
-
-// scope holds the different objects that are read and used during the reconcile.
-type aclScope struct {
-	Device         *v1alpha1.Device
-	ACL            *v1alpha1.AccessControlList
-	Connection     *deviceutil.Connection
-	ProviderConfig *provider.ProviderConfig
-	Provider       provider.ACLProvider
+		Complete(rec)
 }
 
-func (r *AccessControlListReconciler) reconcile(ctx context.Context, s *aclScope) (reterr error) {
-	if s.ACL.Labels == nil {
-		s.ACL.Labels = make(map[string]string)
+func (r *AccessControlListReconciler) Reconcile(ctx context.Context, s *TypedScope[*v1alpha1.AccessControlList, provider.ACLProvider]) (reterr error) {
+	if s.Resource.Labels == nil {
+		s.Resource.Labels = make(map[string]string)
 	}
 
-	s.ACL.Labels[v1alpha1.DeviceLabel] = s.Device.Name
+	s.Resource.Labels[v1alpha1.DeviceLabel] = s.Device.Name
 
 	// Ensure the AccessControlList is owned by the Device.
-	if !controllerutil.HasControllerReference(s.ACL) {
-		if err := controllerutil.SetOwnerReference(s.Device, s.ACL, r.Scheme, controllerutil.WithBlockOwnerDeletion(true)); err != nil {
+	if !controllerutil.HasControllerReference(s.Resource, s.Device, r.Scheme) {
+		if err := controllerutil.SetOwnerReference(s.Device, s.Resource, r.Scheme, controllerutil.WithBlockOwnerDeletion(true)); err != nil {
 			return err
 		}
 	}
@@ -222,19 +87,19 @@ func (r *AccessControlListReconciler) reconcile(ctx context.Context, s *aclScope
 
 	// Ensure the AccessControlList is realized on the provider.
 	err := s.Provider.EnsureACL(ctx, &provider.EnsureACLRequest{
-		ACL:            s.ACL,
+		ACL:            s.Resource,
 		ProviderConfig: s.ProviderConfig,
 	})
 
 	cond := conditions.FromError(err)
 	// As this resource is configuration only, we use the Configured condition as top-level Ready condition.
 	cond.Type = v1alpha1.ReadyCondition
-	conditions.Set(s.ACL, cond)
+	conditions.Set(s.Resource, cond)
 
 	return err
 }
 
-func (r *AccessControlListReconciler) finalize(ctx context.Context, s *aclScope) (reterr error) {
+func (r *AccessControlListReconciler) Finalize(ctx context.Context, s *TypedScope[*v1alpha1.AccessControlList, provider.ACLProvider]) (reterr error) {
 	if err := s.Provider.Connect(ctx, s.Connection); err != nil {
 		return fmt.Errorf("failed to connect to provider: %w", err)
 	}
@@ -245,7 +110,7 @@ func (r *AccessControlListReconciler) finalize(ctx context.Context, s *aclScope)
 	}()
 
 	return s.Provider.DeleteACL(ctx, &provider.DeleteACLRequest{
-		Name:           s.ACL.Spec.Name,
+		Name:           s.Resource.Spec.Name,
 		ProviderConfig: s.ProviderConfig,
 	})
 }