Do not reconcile images and builds being deleted

When an image is being deleted, k8s does not delete the object
immediately, instead it sets the deletion timestamp awaiting
finalization. See [k8s
docs](https://github.com/kubernetes/apimachinery/blob/45d29dc4d66fc2ac83e736e79752ad81a9c6195f/pkg/apis/meta/v1/types.go#L190-L209)
for details

If the kpack image (or its builds) has a finalizer being added by an
external component (such as
[Korifi](https://github.com/cloudfoundry/korifi/blob/17557eb68fed830f3f57abd651882a712fc25f5f/kpack-image-builder/controllers/webhooks/finalizer/finalizer_webhook.go#L25)),
then when the client request the object to be deleted, the image/build
reconcilers keep reconciling the image/build causing new build pods to
be created as the image is being deleted. Even though eventually the
image gets deleted, it takes significant amount of time.

Signed-off-by: Danail Branekov <danailster@gmail.com>
Co-authored-by: Georgi Sabev <georgethebeatle@gmail.com>

Author: danail-branekov

pkg/reconciler/build/build.go

@@ -136,6 +136,10 @@ func (c *Reconciler) Reconcile(ctx context.Context, key string) error {
 		return err
 	}
 
+	if build.DeletionTimestamp != nil {
+		return nil
+	}
+
 	build = build.DeepCopy()
 	build.SetDefaults(ctx)
 

pkg/reconciler/build/build_test.go

@@ -258,6 +258,23 @@ func testBuildReconciler(t *testing.T, when spec.G, it spec.S) {
 			})
 		})
 
+		it("does not reconcile a build being deleted", func() {
+			bld.Status.ObservedGeneration = 1
+
+			bld.Generation = 2
+			deletionTimetamp := metav1.NewTime(time.Now())
+			bld.DeletionTimestamp = &deletionTimetamp
+
+			rt.Test(rtesting.TableRow{
+				Key: key,
+				Objects: []runtime.Object{
+					bld,
+				},
+				WantErr:           false,
+				WantStatusUpdates: []clientgotesting.UpdateActionImpl{},
+			})
+		})
+
 		it("does not update status if there is no update", func() {
 			buildPod, err := podGenerator.Generate(ctx, bld)
 			require.NoError(t, err)

pkg/reconciler/image/image.go

@@ -121,6 +121,10 @@ func (c *Reconciler) Reconcile(ctx context.Context, key string) error {
 		return err
 	}
 
+	if image.DeletionTimestamp != nil {
+		return nil
+	}
+
 	image = image.DeepCopy()
 	image.SetDefaults(ctx)
 

pkg/reconciler/image/image_test.go

@@ -252,6 +252,27 @@ imageWithBuilder := &buildapi.Image{
 			})
 		})
 
+		it("does not reconcile images being deleted", func() {
+			const observedGeneration int64 = 1
+			imageWithBuilder.Status.ObservedGeneration = observedGeneration
+
+			imageWithBuilder.Generation = 2
+			deletionTimetamp := metav1.NewTime(time.Now())
+			imageWithBuilder.DeletionTimestamp = &deletionTimetamp
+
+			rt.Test(rtesting.TableRow{
+				Key: key,
+				Objects: []runtime.Object{
+					imageWithBuilder,
+					builder,
+					clusterBuilder,
+					unresolvedSourceResolver(imageWithBuilder),
+				},
+				WantErr:           false,
+				WantStatusUpdates: []clientgotesting.UpdateActionImpl{},
+			})
+		})
+
 		it("does not update status if there is no status update", func() {
 			rt.Test(rtesting.TableRow{
 				Key: key,