fix: cherry-pick local zone fix to v0.32.x (#5327)

pkg/providers/instancetype/instancetype.go

@@ -47,7 +47,7 @@ import (
 const (
 	InstanceTypesCacheKey         = "types"
 	InstanceTypeOfferingsCacheKey = "offerings"
-	AvailabilityZonesCacheKey     = "zones"
+	ZonesCacheKey                 = "zones"
 )
 
 type Provider struct {
@@ -97,12 +97,9 @@ func (p *Provider) List(ctx context.Context, kc *corev1beta1.KubeletConfiguratio
 	if err != nil {
 		return nil, err
 	}
-	// Get AvailabilityZones from EC2
-	availabilityZones, err := p.getAvailabilityZones(ctx)
-	if err != nil {
-		return nil, err
-	}
-	// Constrain AZs from subnets
+	// Get zones from instancetypeOfferings
+	zones := p.getZones(ctx, instanceTypeOfferings)
+	// Constrain zones from subnets
 	subnets, err := p.subnetProvider.List(ctx, nodeClass)
 	if err != nil {
 		return nil, err
@@ -121,7 +118,7 @@ func (p *Provider) List(ctx context.Context, kc *corev1beta1.KubeletConfiguratio
 		return item.([]*cloudprovider.InstanceType), nil
 	}
 	result := lo.Map(instanceTypes, func(i *ec2.InstanceTypeInfo, _ int) *cloudprovider.InstanceType {
-		return NewInstanceType(ctx, i, kc, p.region, nodeClass, p.createOfferings(ctx, i, instanceTypeOfferings[aws.StringValue(i.InstanceType)], availabilityZones, subnetZones))
+		return NewInstanceType(ctx, i, kc, p.region, nodeClass, p.createOfferings(ctx, i, instanceTypeOfferings[aws.StringValue(i.InstanceType)], zones, subnetZones))
 	})
 	for _, instanceType := range instanceTypes {
 		InstanceTypeVCPU.With(prometheus.Labels{
@@ -142,18 +139,18 @@ func (p *Provider) LivenessProbe(req *http.Request) error {
 	return p.pricingProvider.LivenessProbe(req)
 }
 
-func (p *Provider) createOfferings(ctx context.Context, instanceType *ec2.InstanceTypeInfo, instanceTypeZones, availabilityZones, subnetZones sets.Set[string]) []cloudprovider.Offering {
+func (p *Provider) createOfferings(ctx context.Context, instanceType *ec2.InstanceTypeInfo, instanceTypeZones, zones, subnetZones sets.Set[string]) []cloudprovider.Offering {
 	var offerings []cloudprovider.Offering
-	for az := range availabilityZones {
+	for zone := range zones {
 		// while usage classes should be a distinct set, there's no guarantee of that
 		for capacityType := range sets.NewString(aws.StringValueSlice(instanceType.SupportedUsageClasses)...) {
 			// exclude any offerings that have recently seen an insufficient capacity error from EC2
-			isUnavailable := p.unavailableOfferings.IsUnavailable(*instanceType.InstanceType, az, capacityType)
+			isUnavailable := p.unavailableOfferings.IsUnavailable(*instanceType.InstanceType, zone, capacityType)
 			var price float64
 			var ok bool
 			switch capacityType {
 			case ec2.UsageClassTypeSpot:
-				price, ok = p.pricingProvider.SpotPrice(*instanceType.InstanceType, az)
+				price, ok = p.pricingProvider.SpotPrice(*instanceType.InstanceType, zone)
 			case ec2.UsageClassTypeOnDemand:
 				price, ok = p.pricingProvider.OnDemandPrice(*instanceType.InstanceType)
 			case "capacity-block":
@@ -163,9 +160,9 @@ func (p *Provider) createOfferings(ctx context.Context, instanceType *ec2.Instan
 				logging.FromContext(ctx).Errorf("Received unknown capacity type %s for instance type %s", capacityType, *instanceType.InstanceType)
 				continue
 			}
-			available := !isUnavailable && ok && instanceTypeZones.Has(az) && subnetZones.Has(az)
+			available := !isUnavailable && ok && instanceTypeZones.Has(zone) && subnetZones.Has(zone)
 			offerings = append(offerings, cloudprovider.Offering{
-				Zone:         az,
+				Zone:         zone,
 				CapacityType: capacityType,
 				Price:        price,
 				Available:    available,
@@ -175,34 +172,28 @@ func (p *Provider) createOfferings(ctx context.Context, instanceType *ec2.Instan
 	return offerings
 }
 
-func (p *Provider) getAvailabilityZones(ctx context.Context) (sets.Set[string], error) {
+func (p *Provider) getZones(ctx context.Context, instanceTypeOfferings map[string]sets.Set[string]) sets.Set[string] {
 	// DO NOT REMOVE THIS LOCK ----------------------------------------------------------------------------
 	// We lock here so that multiple callers to getAvailabilityZones do not result in cache misses and multiple
 	// calls to EC2 when we could have just made one call.
 	// TODO @joinnis: This can be made more efficient by holding a Read lock and only obtaining the Write if not in cache
 	p.mu.Lock()
 	defer p.mu.Unlock()
-	if cached, ok := p.cache.Get(AvailabilityZonesCacheKey); ok {
-		return cached.(sets.Set[string]), nil
-	}
-
-	// Get zones from EC2
-	instanceTypeZones := sets.Set[string]{}
-	output, err := p.ec2api.DescribeAvailabilityZonesWithContext(ctx, &ec2.DescribeAvailabilityZonesInput{})
-	if err != nil {
-		return nil, fmt.Errorf("describing availability zones, %w", err)
+	if cached, ok := p.cache.Get(ZonesCacheKey); ok {
+		return cached.(sets.Set[string])
 	}
-	for i := range output.AvailabilityZones {
-		zone := output.AvailabilityZones[i]
-		if aws.StringValue(zone.ZoneType) == "availability-zone" {
-			instanceTypeZones.Insert(aws.StringValue(zone.ZoneName))
+	// Get zones from offerings
+	zones := sets.Set[string]{}
+	for _, offeringZones := range instanceTypeOfferings {
+		for zone := range offeringZones {
+			zones.Insert(zone)
 		}
 	}
-	if p.cm.HasChanged("zones", instanceTypeZones) {
-		logging.FromContext(ctx).With("zones", instanceTypeZones.UnsortedList()).Debugf("discovered availability zones")
+	if p.cm.HasChanged("zones", zones) {
+		logging.FromContext(ctx).With("zones", zones.UnsortedList()).Debugf("discovered zones")
 	}
-	p.cache.Set(AvailabilityZonesCacheKey, instanceTypeZones, 24*time.Hour)
-	return instanceTypeZones, nil
+	p.cache.Set(ZonesCacheKey, zones, 24*time.Hour)
+	return zones
 }
 
 func (p *Provider) getInstanceTypeOfferings(ctx context.Context) (map[string]sets.Set[string], error) {