Add finalize logic

Author: creydr

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/go-logr/logr v1.4.3
 	github.com/onsi/ginkgo/v2 v2.23.3
 	github.com/onsi/gomega v1.37.0
+	github.com/prometheus/client_golang v1.23.2
 	github.com/stretchr/testify v1.11.1
 	gopkg.in/yaml.v3 v3.0.1
 	k8s.io/api v0.34.3
@@ -82,7 +83,6 @@ require (
 	github.com/pjbgf/sha1cd v0.5.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
-	github.com/prometheus/client_golang v1.23.2 // indirect
 	github.com/prometheus/client_model v0.6.2 // indirect
 	github.com/prometheus/common v0.67.4 // indirect
 	github.com/prometheus/procfs v0.19.2 // indirect

internal/controller/function_controller.go

@@ -36,6 +36,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/controller"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
 
@@ -44,6 +45,8 @@ import (
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 )
 
+const functionFinalizer = "function.functions.dev/finalizer"
+
 // FunctionReconciler reconciles a Function object
 type FunctionReconciler struct {
 	client.Client
@@ -82,8 +85,6 @@ func (r *FunctionReconciler) Reconcile(ctx context.Context, req ctrl.Request) (c
 		return ctrl.Result{}, err
 	}
 
-	logger.Info("Reconciling Function", "function", req.NamespacedName)
-
 	// checkout repo
 	branchReference := "main"
 	if function.Spec.Source.Reference != "" {
@@ -101,6 +102,45 @@ func (r *FunctionReconciler) Reconcile(ctx context.Context, req ctrl.Request) (c
 		return ctrl.Result{}, fmt.Errorf("failed to get function metadata: %w", err)
 	}
 
+	if !controllerutil.ContainsFinalizer(function, functionFinalizer) {
+		logger.Info("Adding Finalizer for Function")
+		if ok := controllerutil.AddFinalizer(function, functionFinalizer); !ok {
+			return ctrl.Result{}, fmt.Errorf("failed to add finalizer for function: %w", err)
+		}
+
+		if err = r.Update(ctx, function); err != nil {
+			return ctrl.Result{}, fmt.Errorf("failed to add finalizer for function: %w", err)
+		}
+	}
+
+	// Check if the Function instance is marked to be deleted, which is
+	// indicated by the deletion timestamp being set.
+	if function.GetDeletionTimestamp() != nil {
+		if controllerutil.ContainsFinalizer(function, functionFinalizer) {
+			logger.Info("Performing Finalizer Operations for Function before delete CR")
+
+			//TODO: maybe set some status conditions marking the function as degraded
+
+			// Perform all operations required before removing the finalizer and allow
+			// the Kubernetes API to remove the custom resource.
+			if err := r.Finalize(ctx, metadata.Name, function.Namespace); err != nil {
+				return ctrl.Result{}, fmt.Errorf("failed to perform finalizer for function: %w", err)
+			}
+
+			logger.Info("Removing Finalizer for Function after successfully perform the operations")
+			if ok := controllerutil.RemoveFinalizer(function, functionFinalizer); !ok {
+				return ctrl.Result{}, fmt.Errorf("failed to remove finalizer for function")
+			}
+
+			if err := r.Update(ctx, function); err != nil {
+				return ctrl.Result{}, fmt.Errorf("failed to remove finalizer for function: %w", err)
+			}
+		}
+		return ctrl.Result{}, nil
+	}
+
+	logger.Info("Reconciling Function", "function", req.NamespacedName)
+
 	// deploy if needed
 	deployed, err := r.isDeployed(ctx, metadata.Name, function.Namespace)
 	if err != nil {
@@ -336,3 +376,12 @@ func (r *FunctionReconciler) isMiddlewareLatest(ctx context.Context, metadata fu
 
 	return latestMiddleware == functionMiddleware, nil
 }
+
+func (r *FunctionReconciler) Finalize(ctx context.Context, name, namespace string) error {
+	err := r.FuncCliManager.Delete(ctx, name, namespace)
+	if err != nil {
+		return fmt.Errorf("failed to finalize function: %w", err)
+	}
+
+	return nil
+}

internal/controller/function_controller_test.go

@@ -27,10 +27,12 @@ import (
 	. "github.com/onsi/gomega"
 	"github.com/stretchr/testify/mock"
 	"gopkg.in/yaml.v3"
+	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/client-go/tools/record"
 	"knative.dev/func/pkg/functions"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 
 	functionsdevv1alpha1 "github.com/creydr/func-operator/api/v1alpha1"
@@ -64,8 +66,20 @@ var _ = Describe("Function Controller", func() {
 			err := k8sClient.Get(ctx, typeNamespacedName, resource)
 			Expect(err).NotTo(HaveOccurred())
 
+			By("Remove finalizer to allow deletion")
+			if controllerutil.ContainsFinalizer(resource, functionFinalizer) {
+				controllerutil.RemoveFinalizer(resource, functionFinalizer)
+				Expect(k8sClient.Update(ctx, resource)).To(Succeed())
+			}
+
 			By("Cleanup the specific resource instance Function")
 			Expect(k8sClient.Delete(ctx, resource)).To(Succeed())
+
+			By("Wait for resource to be deleted")
+			Eventually(func() bool {
+				err := k8sClient.Get(ctx, typeNamespacedName, resource)
+				return errors.IsNotFound(err)
+			}).Should(BeTrue())
 		})
 
 		type reconcileTestCase struct {

internal/funccli/Manager_mock.go

@@ -31,6 +31,7 @@ type Manager interface {
 
 	Describe(ctx context.Context, name, namespace string) (funcfn.Instance, error)
 	Deploy(ctx context.Context, repoPath string, namespace string, opts DeployOptions) error
+	Delete(ctx context.Context, name, namespace string) error
 
 	GetCurrentVersion(ctx context.Context) (string, error)
 	GetLatestMiddlewareVersion(ctx context.Context, runtime, invoke string) (string, error)
@@ -234,6 +235,15 @@ func (m *managerImpl) Deploy(ctx context.Context, repoPath string, namespace str
 	return nil
 }
 
+func (m *managerImpl) Delete(ctx context.Context, name, namespace string) error {
+	out, err := m.Run(ctx, "", "delete", "--namespace", namespace, name)
+	if err != nil {
+		return fmt.Errorf("failed to delete function: %q. %w", out, err)
+	}
+
+	return nil
+}
+
 func (m *managerImpl) GetLatestMiddlewareVersion(ctx context.Context, runtime string, invoke string) (string, error) {
 	versions := struct {
 		MiddlewareVersions map[string]map[string]string `json:"middlewareVersions,omitempty"`