Add flag to support ClusterIP exposed CoreDNS

controllers/providers/assistant/assistant.go

@@ -21,10 +21,13 @@ Generated by GoLic, for more details see: https://github.com/AbsaOSS/golic
 import (
 	"time"
 
+	corev1 "k8s.io/api/core/v1"
 	externaldns "sigs.k8s.io/external-dns/endpoint"
 )
 
 type Assistant interface {
+	// GetCoreDNSService returns the CoreDNS Service
+	GetCoreDNSService() (*corev1.Service, error)
 	// CoreDNSExposedIPs retrieves list of exposed IP by CoreDNS
 	CoreDNSExposedIPs() ([]string, error)
 	// GetExternalTargets retrieves slice of targets from external clusters

controllers/providers/assistant/gslb.go

@@ -58,8 +58,8 @@ func NewGslbAssistant(client client.Client, k8gbNamespace string, edgeDNSServers
 	}
 }
 
-// CoreDNSExposedIPs retrieves list of IP's exposed by CoreDNS
-func (r *Gslb) CoreDNSExposedIPs() ([]string, error) {
+// GetCoreDNSService returns the CoreDNS Service
+func (r *Gslb) GetCoreDNSService() (*corev1.Service, error) {
 	serviceList := &corev1.ServiceList{}
 	sel, err := labels.Parse(coreDNSServiceLabel)
 	if err != nil {
@@ -88,7 +88,27 @@ func (r *Gslb) CoreDNSExposedIPs() ([]string, error) {
 		return nil, err
 	}
 	coreDNSService := &serviceList.Items[0]
+	return coreDNSService, nil
+}
 
+// CoreDNSExposedIPs retrieves list of IP's exposed by CoreDNS
+func (r *Gslb) CoreDNSExposedIPs() ([]string, error) {
+	coreDNSService, err := r.GetCoreDNSService()
+	if err != nil {
+		return nil, err
+	}
+	if coreDNSService.Spec.Type == "ClusterIP" {
+		if len(coreDNSService.Spec.ClusterIPs) == 0 {
+			errMessage := "no ClusterIPs found"
+			log.Warn().
+				Str("serviceName", coreDNSService.Name).
+				Msg(errMessage)
+			err := coreerrors.New(errMessage)
+			return nil, err
+		}
+		return coreDNSService.Spec.ClusterIPs, nil
+	}
+	// LoadBalancer / ExternalName / NodePort service
 	var lb corev1.LoadBalancerIngress
 	if len(coreDNSService.Status.LoadBalancer.Ingress) == 0 {
 		errMessage := "no LoadBalancer ExternalIPs are found"