reafctor: change to pathc all resource creations

Signed-off-by: Sandor Szücs <sandor.szuecs@zalando.de>

Author: szuecs

pkg/core/stack_resources.go

@@ -76,6 +76,23 @@ func objectMetaInjectLabels(objectMeta metav1.ObjectMeta, labels map[string]stri
 	return objectMeta
 }
 
+// patchForwardBackend rewrites a RouteGroupSpec to send all traffic to another cluster chosen by the operator of skipper
+func patchForwardBackend(rg *rgv1.RouteGroupSpec) {
+	rg.Backends = []rgv1.RouteGroupBackend{
+		{
+			Name: forwardBackendName,
+			Type: rgv1.ForwardRouteGroupBackend,
+		},
+	}
+	for _, route := range rg.Routes {
+		route.Backends = []rgv1.RouteGroupBackendReference{
+			{
+				BackendName: forwardBackendName,
+			},
+		}
+	}
+}
+
 func (sc *StackContainer) objectMeta(segment bool) metav1.ObjectMeta {
 	resourceLabels := mapCopy(sc.Stack.Labels)
 
@@ -224,6 +241,12 @@ func (sc *StackContainer) GenerateDeployment() *appsv1.Deployment {
 	if strategy != nil {
 		deployment.Spec.Strategy = *strategy
 	}
+
+	if _, clusterMigration := sc.Stack.Annotations[forwardBackendAnnotation]; clusterMigration {
+		i := int32(1)
+		deployment.Spec.Replicas = &i
+	}
+
 	return deployment
 }
 
@@ -281,6 +304,12 @@ func (sc *StackContainer) GenerateHPA() (
 		result.Spec.MinReplicas = &pr
 	}
 
+	if _, clusterMigration := sc.Stack.Annotations[forwardBackendAnnotation]; clusterMigration {
+		i := int32(1)
+		result.Spec.MinReplicas = &i
+		result.Spec.MaxReplicas = i
+	}
+
 	return result, nil
 }
 
@@ -430,6 +459,9 @@ func (sc *StackContainer) generateIngress(segment bool) (
 			Rules: rules,
 		},
 	}
+	if _, clusterMigration := sc.Stack.Annotations[forwardBackendAnnotation]; clusterMigration {
+		result.Annotations["zalando.org/skipper-backend"] = "forward"
+	}
 
 	// insert annotations
 	result.Annotations = mergeLabels(
@@ -529,6 +561,10 @@ func (sc *StackContainer) generateRouteGroup(segment bool) (
 		sc.routeGroupSpec.GetAnnotations(),
 	)
 
+	if _, clusterMigration := sc.Stack.Annotations[forwardBackendAnnotation]; clusterMigration {
+		patchForwardBackend(&result.Spec)
+	}
+
 	return result, nil
 }
 

pkg/core/stackset.go

@@ -77,6 +77,9 @@ func (ssc *StackSetContainer) NewStack() (*StackContainer, string) {
 
 		if ssc.StackSet.Spec.ExternalIngress != nil {
 			spec.ExternalIngress = ssc.StackSet.Spec.ExternalIngress.DeepCopy()
+			if forwardMigration {
+				spec.ExternalIngress.Annotations[forwardBackendAnnotation] = forwardBackendName
+			}
 		}
 
 		if ssc.StackSet.Spec.RouteGroup != nil {

pkg/core/types.go

@@ -427,15 +427,7 @@ func (sc *StackContainer) updateStackResources() error {
 // cluster. RouteGroup will get a patched backend, such that it does
 // the same as ingress.
 func (sc *StackContainer) updateFromResources() {
-	fwdVal, clusterMigration := sc.Stack.Annotations[forwardBackendAnnotation]
-
-	if clusterMigration {
-		sc.Stack.Spec.ExternalIngress.Annotations[forwardBackendAnnotation] = fwdVal
-		// we do not use these pods so reduce wasted resources!
-		sc.stackReplicas = 1
-	} else {
-		sc.stackReplicas = effectiveReplicas(sc.Stack.Spec.StackSpec.Replicas)
-	}
+	sc.stackReplicas = effectiveReplicas(sc.Stack.Spec.StackSpec.Replicas)
 
 	var deploymentUpdated, serviceUpdated, ingressUpdated, routeGroupUpdated, hpaUpdated bool
 	var ingressSegmentUpdated, routeGroupSegmentUpdated bool
@@ -444,18 +436,11 @@ func (sc *StackContainer) updateFromResources() {
 	if sc.Resources.Deployment != nil {
 		deployment := sc.Resources.Deployment
 
-		if clusterMigration {
-			// we do not use these pods so reduce wasted resources!
-			sc.deploymentReplicas = 1
-			sc.createdReplicas = 1
-			sc.readyReplicas = 1
-			sc.updatedReplicas = 1
-		} else {
-			sc.deploymentReplicas = effectiveReplicas(deployment.Spec.Replicas)
-			sc.createdReplicas = deployment.Status.Replicas
-			sc.readyReplicas = deployment.Status.ReadyReplicas
-			sc.updatedReplicas = deployment.Status.UpdatedReplicas
-		}
+		sc.deploymentReplicas = effectiveReplicas(deployment.Spec.Replicas)
+		sc.createdReplicas = deployment.Status.Replicas
+		sc.readyReplicas = deployment.Status.ReadyReplicas
+		sc.updatedReplicas = deployment.Status.UpdatedReplicas
+
 		deploymentUpdated = IsResourceUpToDate(sc.Stack, sc.Resources.Deployment.ObjectMeta) && deployment.Status.ObservedGeneration == deployment.Generation
 	}
 
@@ -467,18 +452,12 @@ func (sc *StackContainer) updateFromResources() {
 		// the per-stack ingress must either be present and up-to-date, or not present and not expected.
 		// the per-stack ingress is not expected if the stack has no hostnames matching the cluster domain.
 		if sc.Resources.Ingress != nil {
-			if clusterMigration {
-				sc.Resources.Ingress.Annotations["zalando.org/skipper-backend"] = "forward"
-			}
 			ingressUpdated = IsResourceUpToDate(sc.Stack, sc.Resources.Ingress.ObjectMeta)
 		} else {
 			hostnames := sc.stackHostnames(sc.ingressSpec, false)
 			ingressUpdated = len(hostnames) == 0
 		}
 		if sc.Resources.IngressSegment != nil {
-			if clusterMigration {
-				sc.Resources.IngressSegment.Annotations["zalando.org/skipper-backend"] = "forward"
-			}
 			ingressSegmentUpdated = IsResourceUpToDate(sc.Stack, sc.Resources.IngressSegment.ObjectMeta)
 		}
 	} else {
@@ -492,20 +471,13 @@ func (sc *StackContainer) updateFromResources() {
 		// the per-stack route group must either be present and up-to-date, or not present and not expected.
 		// the per-stack route group is not expected if the stack has no hostnames matching the cluster domain.
 		if sc.Resources.RouteGroup != nil {
-			if clusterMigration {
-				patchForwardBackend(&sc.Resources.RouteGroup.Spec)
-			}
 			routeGroupUpdated = IsResourceUpToDate(sc.Stack, sc.Resources.RouteGroup.ObjectMeta)
 		} else {
 			hostnames := sc.stackHostnames(sc.routeGroupSpec, false)
 			routeGroupUpdated = len(hostnames) == 0
 		}
 
 		if sc.Resources.RouteGroupSegment != nil {
-			if clusterMigration {
-				patchForwardBackend(&sc.Resources.RouteGroupSegment.Spec)
-			}
-
 			routeGroupSegmentUpdated = IsResourceUpToDate(
 				sc.Stack,
 				sc.Resources.RouteGroupSegment.ObjectMeta,
@@ -518,10 +490,8 @@ func (sc *StackContainer) updateFromResources() {
 	}
 
 	// hpa not used if we migrate cluster to reduce wasted resources
-	if sc.IsAutoscaled() && !clusterMigration {
+	if sc.IsAutoscaled() {
 		hpaUpdated = sc.Resources.HPA != nil && IsResourceUpToDate(sc.Stack, sc.Resources.HPA.ObjectMeta)
-	} else {
-		hpaUpdated = sc.Resources.HPA == nil
 	}
 
 	// aggregated 'resources updated' for the readiness
@@ -535,27 +505,11 @@ func (sc *StackContainer) updateFromResources() {
 
 	status := sc.Stack.Status
 	sc.noTrafficSince = unwrapTime(status.NoTrafficSince)
-	// do not prescale on cluster migration to reduce wasted resources
-	if status.Prescaling.Active && !clusterMigration {
+
+	if status.Prescaling.Active {
 		sc.prescalingActive = true
 		sc.prescalingReplicas = status.Prescaling.Replicas
 		sc.prescalingDesiredTrafficWeight = status.Prescaling.DesiredTrafficWeight
 		sc.prescalingLastTrafficIncrease = unwrapTime(status.Prescaling.LastTrafficIncrease)
 	}
 }
-
-func patchForwardBackend(rg *rgv1.RouteGroupSpec) {
-	rg.Backends = []rgv1.RouteGroupBackend{
-		{
-			Name: forwardBackendName,
-			Type: rgv1.ForwardRouteGroupBackend,
-		},
-	}
-	for _, route := range rg.Routes {
-		route.Backends = []rgv1.RouteGroupBackendReference{
-			{
-				BackendName: forwardBackendName,
-			},
-		}
-	}
-}