GH-496 GW target own cluster

pkg/controllers/dnspolicy/dnspolicy_dnsrecords.go

@@ -146,8 +146,10 @@ func (r *DNSPolicyReconciler) buildClusterGateway(ctx context.Context, downstrea
 	singleClusterAddresses := make([]gatewayv1beta1.GatewayAddress, len(clusterAddress))
 
 	mc := &clusterv1.ManagedCluster{}
-	if err := r.Client().Get(ctx, client.ObjectKey{Name: downstreamClusterName}, mc, &client.GetOptions{}); err != nil {
-		return target, err
+	if downstreamClusterName != dns.NoneCluster {
+		if err := r.Client().Get(ctx, client.ObjectKey{Name: downstreamClusterName}, mc, &client.GetOptions{}); err != nil {
+			return target, err
+		}
 	}
 
 	for i, addr := range clusterAddress {
@@ -174,7 +176,7 @@ func getClusterGatewayAddresses(gw *gatewayv1beta1.Gateway) map[string][]gateway
 		var gatewayAddresses []gatewayv1beta1.GatewayAddress
 
 		//Default to Single Cluster (Normal Gateway Status)
-		cluster := "none"
+		cluster := dns.NoneCluster
 		addressValue := address.Value
 
 		//Check for Multi Cluster (MGC Gateway Status)

pkg/dns/target.go

@@ -3,12 +3,14 @@ package dns
 import (
 	"crypto/sha256"
 	"fmt"
+	"reflect"
 	"strings"
 
 	"github.com/martinlindhe/base36"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
+	clusterv1 "open-cluster-management.io/api/cluster/v1"
 	gatewayv1beta1 "sigs.k8s.io/gateway-api/apis/v1beta1"
 
 	"github.com/Kuadrant/multicluster-gateway-controller/pkg/apis/v1alpha1"
@@ -19,6 +21,7 @@ const (
 	DefaultGeo              GeoCode = "default"
 	WildcardGeo             GeoCode = "*"
 	LabelLBAttributeGeoCode         = "kuadrant.io/lb-attribute-geo-code"
+	NoneCluster                     = "none"
 )
 
 // MultiClusterGatewayTarget represents a Gateway that is placed on multiple clusters (ClusterGateway).
@@ -83,6 +86,7 @@ func (t *MultiClusterGatewayTarget) setClusterGatewayTargets(clusterGateways []C
 }
 
 // ClusterGateway contains the addresses of a Gateway on a single cluster and the attributes of the target cluster.
+// If represent a single-cluster implementation of a gateway Cluster is nil
 type ClusterGateway struct {
 	Cluster          metav1.Object
 	GatewayAddresses []gatewayv1beta1.GatewayAddress
@@ -134,7 +138,10 @@ func (t *ClusterGatewayTarget) GetWeight() int {
 }
 
 func (t *ClusterGatewayTarget) GetName() string {
-	return t.Cluster.GetName()
+	if !t.noneCluster() {
+		return t.Cluster.GetName()
+	}
+	return NoneCluster
 }
 
 func (t *ClusterGatewayTarget) GetShortCode() string {
@@ -143,7 +150,7 @@ func (t *ClusterGatewayTarget) GetShortCode() string {
 
 func (t *ClusterGatewayTarget) setGeo(defaultGeo GeoCode) {
 	geoCode := defaultGeo
-	if geoCode == DefaultGeo {
+	if geoCode == DefaultGeo || t.noneCluster() {
 		t.Geo = &geoCode
 		return
 	}
@@ -212,6 +219,10 @@ func dnsHealthCheckProbeName(address, gatewayName, listenerName string) string {
 
 func (t *ClusterGatewayTarget) setWeight(defaultWeight int, customWeights []*v1alpha1.CustomWeight) error {
 	weight := defaultWeight
+	if t.noneCluster() {
+		t.Weight = &weight
+		return nil
+	}
 	for k := range customWeights {
 		cw := customWeights[k]
 		selector, err := metav1.LabelSelectorAsSelector(cw.Selector)
@@ -228,6 +239,13 @@ func (t *ClusterGatewayTarget) setWeight(defaultWeight int, customWeights []*v1a
 	return nil
 }
 
+func (t *ClusterGatewayTarget) noneCluster() bool {
+	if reflect.DeepEqual(t.Cluster, &clusterv1.ManagedCluster{}) {
+		return true
+	}
+	return false
+}
+
 func ToBase36hash(s string) string {
 	hash := sha256.Sum224([]byte(s))
 	// convert the hash to base36 (alphanumeric) to decrease collision probabilities