add dualstack support for AWS provider with ALB ingress controllers

endpoint/labels.go

@@ -38,6 +38,9 @@ const (
 	// AWSSDDescriptionLabel label responsible for storing raw owner/resource combination information in the Labels
 	// supposed to be inserted by AWS SD Provider, and parsed into OwnerLabelKey and ResourceLabelKey key by AWS SD Registry
 	AWSSDDescriptionLabel = "aws-sd-description"
+
+	// DualstackLabelKey is the name of the label that identifies dualstack endpoints
+	DualstackLabelKey = "dualstack"
 )
 
 // Labels store metadata related to the endpoint

provider/aws.go

@@ -407,60 +407,74 @@ func (p *AWSProvider) newChanges(action string, endpoints []*endpoint.Endpoint,
 	changes := make([]*route53.Change, 0, len(endpoints))
 
 	for _, endpoint := range endpoints {
-		changes = append(changes, p.newChange(action, endpoint, recordsCache, zones))
+		change, dualstack := p.newChange(action, endpoint, recordsCache, zones)
+		changes = append(changes, change)
+		if dualstack {
+			// make a copy of change, modify RRS type to AAAA, then add new change
+			rrs := *change.ResourceRecordSet
+			change2 := &route53.Change{Action: change.Action, ResourceRecordSet: &rrs}
+			change2.ResourceRecordSet.Type = aws.String(route53.RRTypeAaaa)
+			changes = append(changes, change2)
+		}
 	}
 
 	return changes
 }
 
-// newChange returns a Change of the given record by the given action, e.g.
+// newChange returns a route53 Change and a boolean indicating if there should also be a change to a AAAA record
+// returned Change is based on the given record by the given action, e.g.
 // action=ChangeActionCreate returns a change for creation of the record and
 // action=ChangeActionDelete returns a change for deletion of the record.
-func (p *AWSProvider) newChange(action string, endpoint *endpoint.Endpoint, recordsCache []*endpoint.Endpoint, zones map[string]*route53.HostedZone) *route53.Change {
+func (p *AWSProvider) newChange(action string, ep *endpoint.Endpoint, recordsCache []*endpoint.Endpoint, zones map[string]*route53.HostedZone) (*route53.Change, bool) {
 	change := &route53.Change{
 		Action: aws.String(action),
 		ResourceRecordSet: &route53.ResourceRecordSet{
-			Name: aws.String(endpoint.DNSName),
+			Name: aws.String(ep.DNSName),
 		},
 	}
+	dualstack := false
 
-	if isAWSLoadBalancer(endpoint) {
+	if isAWSLoadBalancer(ep) {
 		evalTargetHealth := p.evaluateTargetHealth
-		if prop, ok := endpoint.GetProviderSpecificProperty(providerSpecificEvaluateTargetHealth); ok {
+		if prop, ok := ep.GetProviderSpecificProperty(providerSpecificEvaluateTargetHealth); ok {
 			evalTargetHealth = prop.Value == "true"
 		}
+		// If the endpoint has a Dualstack label, append a change for AAAA record as well.
+		if val, ok := ep.Labels[endpoint.DualstackLabelKey]; ok {
+			dualstack = val == "true"
+		}
 
 		change.ResourceRecordSet.Type = aws.String(route53.RRTypeA)
 		change.ResourceRecordSet.AliasTarget = &route53.AliasTarget{
-			DNSName:              aws.String(endpoint.Targets[0]),
-			HostedZoneId:         aws.String(canonicalHostedZone(endpoint.Targets[0])),
+			DNSName:              aws.String(ep.Targets[0]),
+			HostedZoneId:         aws.String(canonicalHostedZone(ep.Targets[0])),
 			EvaluateTargetHealth: aws.Bool(evalTargetHealth),
 		}
-	} else if hostedZone := isAWSAlias(endpoint, recordsCache); hostedZone != "" {
+	} else if hostedZone := isAWSAlias(ep, recordsCache); hostedZone != "" {
 		for _, zone := range zones {
 			change.ResourceRecordSet.Type = aws.String(route53.RRTypeA)
 			change.ResourceRecordSet.AliasTarget = &route53.AliasTarget{
-				DNSName:              aws.String(endpoint.Targets[0]),
+				DNSName:              aws.String(ep.Targets[0]),
 				HostedZoneId:         aws.String(cleanZoneID(*zone.Id)),
 				EvaluateTargetHealth: aws.Bool(p.evaluateTargetHealth),
 			}
 		}
 	} else {
-		change.ResourceRecordSet.Type = aws.String(endpoint.RecordType)
-		if !endpoint.RecordTTL.IsConfigured() {
+		change.ResourceRecordSet.Type = aws.String(ep.RecordType)
+		if !ep.RecordTTL.IsConfigured() {
 			change.ResourceRecordSet.TTL = aws.Int64(recordTTL)
 		} else {
-			change.ResourceRecordSet.TTL = aws.Int64(int64(endpoint.RecordTTL))
+			change.ResourceRecordSet.TTL = aws.Int64(int64(ep.RecordTTL))
 		}
-		change.ResourceRecordSet.ResourceRecords = make([]*route53.ResourceRecord, len(endpoint.Targets))
-		for idx, val := range endpoint.Targets {
+		change.ResourceRecordSet.ResourceRecords = make([]*route53.ResourceRecord, len(ep.Targets))
+		for idx, val := range ep.Targets {
 			change.ResourceRecordSet.ResourceRecords[idx] = &route53.ResourceRecord{
 				Value: aws.String(val),
 			}
 		}
 	}
 
-	return change
+	return change, dualstack
 }
 
 func (p *AWSProvider) tagsForZone(zoneID string) (map[string]string, error) {

source/ingress.go

@@ -37,6 +37,13 @@ import (
 	"k8s.io/client-go/tools/cache"
 )
 
+const (
+	// The annotation used for determining if an ALB ingress is dualstack
+	ALBDualstackAnnotationKey = "alb.ingress.kubernetes.io/ip-address-type"
+	// The value of the ALB dualstack annotation that indicates it is dualstack
+	ALBDualstackAnnotationValue = "dualstack"
+)
+
 // ingressSource is an implementation of Source for Kubernetes ingress objects.
 // Ingress implementation will use the spec.rules.host value for the hostname
 // Use targetAnnotationKey to explicitly set Endpoint. (useful if the ingress
@@ -148,6 +155,7 @@ func (sc *ingressSource) Endpoints() ([]*endpoint.Endpoint, error) {
 
 		log.Debugf("Endpoints generated from ingress: %s/%s: %v", ing.Namespace, ing.Name, ingEndpoints)
 		sc.setResourceLabel(ing, ingEndpoints)
+		sc.setDualstackLabel(ing, ingEndpoints)
 		endpoints = append(endpoints, ingEndpoints...)
 	}
 
@@ -228,6 +236,14 @@ func (sc *ingressSource) setResourceLabel(ingress *v1beta1.Ingress, endpoints []
 	}
 }
 
+func (sc *ingressSource) setDualstackLabel(ingress *v1beta1.Ingress, endpoints []*endpoint.Endpoint) {
+	val, ok := ingress.Annotations[ALBDualstackAnnotationKey]
+	if ok && val == ALBDualstackAnnotationValue {
+		log.Debugf("Adding dualstack label to ingress %s/%s.", ingress.Namespace, ingress.Name)
+		for _, ep := range endpoints { ep.Labels[endpoint.DualstackLabelKey] = "true" }
+	}
+}
+
 // endpointsFromIngress extracts the endpoints from ingress object
 func endpointsFromIngress(ing *v1beta1.Ingress, ignoreHostnameAnnotation bool) []*endpoint.Endpoint {
 	var endpoints []*endpoint.Endpoint