Add new KPA status for dependencies (#8809)

* Add new Kpa status for dependencies

This initial version only deals with SKS and sets deps
not ready if SKS is not ready and ready otherwise.

Lots of test churn... :-)

* more files to fix

* review

* restore tests

* rewrite as sks only cond

* holdout

* more fixes

pkg/apis/autoscaling/v1alpha1/pa_lifecycle.go

@@ -31,6 +31,7 @@ import (
 var podCondSet = apis.NewLivingConditionSet(
 	PodAutoscalerConditionActive,
 	PodAutoscalerConditionScaleTargetInitialized,
+	PodAutoscalerSKSReady,
 )
 
 // GetConditionSet retrieves the condition set for this resource. Implements the KRShaped interface.
@@ -185,6 +186,16 @@ func (pas *PodAutoscalerStatus) MarkScaleTargetInitialized() {
 	podCondSet.Manage(pas).MarkTrue(PodAutoscalerConditionScaleTargetInitialized)
 }
 
+// MarkSKSReady marks the PA condition denoting that SKS is ready.
+func (pas *PodAutoscalerStatus) MarkSKSReady() {
+	podCondSet.Manage(pas).MarkTrue(PodAutoscalerSKSReady)
+}
+
+// MarkSKSNotReady marks the PA condation that SKS is not yet ready.
+func (pas *PodAutoscalerStatus) MarkSKSNotReady(mes string) {
+	podCondSet.Manage(pas).MarkUnknown(PodAutoscalerSKSReady, "NotReady", mes)
+}
+
 // GetCondition gets the condition `t`.
 func (pas *PodAutoscalerStatus) GetCondition(t apis.ConditionType) *apis.Condition {
 	return podCondSet.Manage(pas).GetCondition(t)
@@ -248,7 +259,7 @@ func (pas *PodAutoscalerStatus) CanFailActivation(now time.Time, idlePeriod time
 
 // inStatusFor returns positive duration if the PodAutoscalerStatus's Active condition has stayed in
 // the specified status for at least the specified duration. Otherwise it returns negative duration,
-// including when the status is undetermined (Active condition is not found.)
+// including when the status is undetermined.
 func (pas *PodAutoscalerStatus) inStatusFor(status corev1.ConditionStatus, now time.Time, dur time.Duration) time.Duration {
 	cond := pas.GetCondition(PodAutoscalerConditionActive)
 	if cond == nil || cond.Status != status {

pkg/apis/autoscaling/v1alpha1/pa_lifecycle_test.go

@@ -251,6 +251,7 @@ func TestInactiveFor(t *testing.T) {
 		})
 	}
 }
+
 func TestActiveFor(t *testing.T) {
 	now := time.Now()
 	cases := []struct {
@@ -977,21 +978,41 @@ func TestTypicalFlow(t *testing.T) {
 	r.InitializeConditions()
 	apistest.CheckConditionOngoing(r, PodAutoscalerConditionActive, t)
 	apistest.CheckConditionOngoing(r, PodAutoscalerConditionReady, t)
+	apistest.CheckConditionOngoing(r, PodAutoscalerSKSReady, t)
+	apistest.CheckConditionOngoing(r, PodAutoscalerConditionScaleTargetInitialized, t)
+
+	r.MarkActive()
+	r.MarkSKSReady()
+	apistest.CheckConditionSucceeded(r, PodAutoscalerSKSReady, t)
+	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionActive, t)
+	apistest.CheckConditionOngoing(r, PodAutoscalerConditionReady, t)
 
 	// When we see traffic, mark ourselves active.
 	r.MarkActive()
 	r.MarkScaleTargetInitialized()
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionScaleTargetInitialized, t)
+	apistest.CheckConditionSucceeded(r, PodAutoscalerSKSReady, t)
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionActive, t)
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionReady, t)
 
 	// Check idempotency.
 	r.MarkActive()
 	r.MarkScaleTargetInitialized()
+	r.MarkSKSReady()
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionScaleTargetInitialized, t)
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionActive, t)
+	apistest.CheckConditionSucceeded(r, PodAutoscalerSKSReady, t)
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionReady, t)
 
+	r.MarkSKSNotReady("something something private")
+	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionScaleTargetInitialized, t)
+	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionActive, t)
+	apistest.CheckConditionOngoing(r, PodAutoscalerSKSReady, t)
+	apistest.CheckConditionOngoing(r, PodAutoscalerConditionReady, t)
+
+	// Restore.
+	r.MarkSKSReady()
+
 	// When we stop seeing traffic, mark ourselves inactive.
 	r.MarkInactive("TheReason", "the message")
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionScaleTargetInitialized, t)
@@ -1014,9 +1035,10 @@ func TestTypicalFlow(t *testing.T) {
 	if !r.IsActive() {
 		t.Error("Active was not set.")
 	}
-	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionScaleTargetInitialized, t)
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionActive, t)
+	apistest.CheckConditionSucceeded(r, PodAutoscalerSKSReady, t)
 	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionReady, t)
+	apistest.CheckConditionSucceeded(r, PodAutoscalerConditionScaleTargetInitialized, t)
 }
 
 func TestTargetBC(t *testing.T) {

pkg/apis/autoscaling/v1alpha1/pa_types.go

@@ -117,6 +117,8 @@ const (
 	PodAutoscalerConditionScaleTargetInitialized apis.ConditionType = "ScaleTargetInitialized"
 	// PodAutoscalerConditionActive is set when the PodAutoscaler's ScaleTargetRef is receiving traffic.
 	PodAutoscalerConditionActive apis.ConditionType = "Active"
+	// PodAutoscalerCondtionDependenciesReady is set when SKS is ready.
+	PodAutoscalerSKSReady = "SKSReady"
 )
 
 // PodAutoscalerStatus communicates the observed state of the PodAutoscaler (from the controller).

pkg/reconciler/autoscaling/kpa/kpa.go

@@ -79,12 +79,13 @@ func (c *Reconciler) ReconcileKind(ctx context.Context, pa *pav1alpha1.PodAutosc
 	}
 
 	// Having an SKS and its PrivateServiceName is a prerequisite for all upcoming steps.
-	if sks == nil || (sks != nil && sks.Status.PrivateServiceName == "") {
+	if sks == nil || sks.Status.PrivateServiceName == "" {
 		// Before we can reconcile decider and get real number of activators
 		// we start with default of 2.
 		if _, err = c.ReconcileSKS(ctx, pa, nv1alpha1.SKSOperationModeServe, 0 /*numActivators == all*/); err != nil {
 			return fmt.Errorf("error reconciling SKS: %w", err)
 		}
+		pa.Status.MarkSKSNotReady("No Private Service Name") // In both cases this is true.
 		return computeStatus(ctx, pa, podCounts{want: scaleUnknown}, logger)
 	}
 
@@ -138,7 +139,12 @@ func (c *Reconciler) ReconcileKind(ctx context.Context, pa *pav1alpha1.PodAutosc
 	// If SKS is not ready — ensure we're not becoming ready.
 	// TODO: see if we can perhaps propagate the SKS state to computing active status.
 	if !sks.IsReady() {
+		logger.Debug("SKS is not ready, marking SKS status not ready")
 		ready = 0
+		pa.Status.MarkSKSNotReady(sks.Status.GetCondition(nv1alpha1.ServerlessServiceConditionReady).Message)
+	} else {
+		logger.Debug("SKS is ready, marking SKS status ready")
+		pa.Status.MarkSKSReady()
 	}
 
 	logger.Infof("PA scale got=%d, want=%d, desiredPods=%d ebc=%d", ready, want,