If applied, this commit will allow the migration from an hpa to a scaled object

Signed-off-by: James Geisler <geislerjamesd@gmail.com>

pkg/apis/keda/v1alpha1/scaledobject.go

@@ -103,6 +103,8 @@ type AdvancedConfig struct {
 
 // HorizontalPodAutoscalerConfig specifies horizontal scale config
 type HorizontalPodAutoscalerConfig struct {
+	// +optional
+	Name string `json:"name,omitempty"`
 	// +optional
 	Behavior *autoscalingv2beta2.HorizontalPodAutoscalerBehavior `json:"behavior,omitempty"`
 }

pkg/canary/scaled_object_reconciler.go

@@ -17,6 +17,7 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 )
 
 // ScaledObjectReconciler is a ScalerReconciler that reconciles KEDA ScaledObjects.
@@ -47,6 +48,8 @@ func (sor *ScaledObjectReconciler) reconcilePrimaryScaler(cd *flaggerv1.Canary,
 
 	setPrimaryScaledObjectQueries(cd, targetSoClone.Spec.Triggers)
 
+	setPrimaryScaledObjectHPA(targetSoClone)
+
 	soSpec := keda.ScaledObjectSpec{
 		ScaleTargetRef: &keda.ScaleTarget{
 			Name:                   primaryName,
@@ -77,7 +80,8 @@ func (sor *ScaledObjectReconciler) reconcilePrimaryScaler(cd *flaggerv1.Canary,
 	primarySo, err := sor.flaggerClient.KedaV1alpha1().ScaledObjects(cd.Namespace).Get(context.TODO(), primarySoName, metav1.GetOptions{})
 	if errors.IsNotFound(err) {
 		primarySo = &keda.ScaledObject{
-			ObjectMeta: makeObjectMeta(primarySoName, targetSoClone.Labels, cd),
+			// Passing in the annotations from the targetSo so that they are carried over to the primarySo. This is required so that the transfer ownership annotation can be added.
+			ObjectMeta: makeObjectMetaSo(primarySoName, targetSoClone.Labels, targetSoClone.Annotations, cd),
 			Spec:       soSpec,
 		}
 		_, err = sor.flaggerClient.KedaV1alpha1().ScaledObjects(cd.Namespace).Create(context.TODO(), primarySo, metav1.CreateOptions{})
@@ -206,3 +210,33 @@ func setPrimaryScaledObjectQueries(cd *flaggerv1.Canary, triggers []keda.ScaleTr
 		}
 	}
 }
+
+func makeObjectMetaSo(name string, labels map[string]string, annotations map[string]string, cd *flaggerv1.Canary) metav1.ObjectMeta {
+	return metav1.ObjectMeta{
+		Name:        name,
+		Namespace:   cd.Namespace,
+		Labels:      filterMetadata(labels),
+		Annotations: filterMetadata(annotations),
+		OwnerReferences: []metav1.OwnerReference{
+			*metav1.NewControllerRef(cd, schema.GroupVersionKind{
+				Group:   flaggerv1.SchemeGroupVersion.Group,
+				Version: flaggerv1.SchemeGroupVersion.Version,
+				Kind:    flaggerv1.CanaryKind,
+			}),
+		},
+	}
+}
+
+func setPrimaryScaledObjectHPA(targetSoClone *keda.ScaledObject) {
+	if targetSoClone.Spec.Advanced == nil {
+		targetSoClone.Spec.Advanced = &keda.AdvancedConfig{}
+	}
+	if targetSoClone.Spec.Advanced.HorizontalPodAutoscalerConfig == nil {
+		targetSoClone.Spec.Advanced.HorizontalPodAutoscalerConfig = &keda.HorizontalPodAutoscalerConfig{}
+	}
+	if targetSoClone.Spec.Advanced.HorizontalPodAutoscalerConfig.Name != "" {
+		// if the target scaled object has the hpa name set, then append "-primary" to the primary scaled object hpa name
+		// if the target scaled object does not have the hpa name set, then it will use the default set by keda
+		targetSoClone.Spec.Advanced.HorizontalPodAutoscalerConfig.Name = fmt.Sprintf("%s-primary", targetSoClone.Spec.Advanced.HorizontalPodAutoscalerConfig.Name)
+	}
+}

pkg/canary/scaled_object_reconciler_test.go

@@ -29,6 +29,10 @@ func Test_reconcilePrimaryScaledObject(t *testing.T) {
 
 	primarySO, err := mocks.flaggerClient.KedaV1alpha1().ScaledObjects("default").Get(context.TODO(), "podinfo-primary", metav1.GetOptions{})
 	require.NoError(t, err)
+	// test that the hpa ownership annotation is added to the primarySO
+	assert.Equal(t, primarySO.ObjectMeta.Annotations["scaledobject.keda.sh/transfer-hpa-ownership"], "true")
+	// test that the horizontalpodautoscalerconfig is set to 'podinfo-primary', so that it takes over ownership of the HPA
+	assert.Equal(t, primarySO.Spec.Advanced.HorizontalPodAutoscalerConfig.Name, "podinfo-primary")
 	assert.Equal(t, primarySO.Spec.ScaleTargetRef.Name, fmt.Sprintf("%s-primary", mocks.canary.Spec.TargetRef.Name))
 	assert.Equal(t, int(*primarySO.Spec.PollingInterval), 10)
 	assert.Equal(t, int(*primarySO.Spec.MinReplicaCount), 1)

pkg/canary/scaler_reconciler_fixture_test.go

@@ -154,11 +154,19 @@ func newScaledObject() *keda.ScaledObject {
 		ObjectMeta: metav1.ObjectMeta{
 			Namespace: "default",
 			Name:      "podinfo",
+			Annotations: map[string]string{
+				"scaledobject.keda.sh/transfer-hpa-ownership": "true",
+			},
 		},
 		Spec: keda.ScaledObjectSpec{
 			ScaleTargetRef: &keda.ScaleTarget{
 				Name: "podinfo",
 			},
+			Advanced: &keda.AdvancedConfig{
+				HorizontalPodAutoscalerConfig: &keda.HorizontalPodAutoscalerConfig{
+					Name: "podinfo",
+				},
+			},
 			PollingInterval: int32p(10),
 			MinReplicaCount: int32p(1),
 			MaxReplicaCount: int32p(4),