From d1b3f8e1762924d1678fb5f3f91252af956df2c4 Mon Sep 17 00:00:00 2001
From: Thibault Jamet <thibault.jamet@adevinta.com>
Date: Fri, 29 Nov 2024 17:16:18 +0100
Subject: [PATCH] Refactor DNS name extraction

Goal
---

Ease the implementation of CRD based multi-ingress controller traffic routing

Change-Id: I46f513341ce01ec6e9d67897c6d0cb58aeec3021
---
 pkg/controllers/ingress_controller.go      | 34 +++++++++++++++-------
 pkg/controllers/ingress_controller_test.go | 19 ++++++++++++
 2 files changed, 43 insertions(+), 10 deletions(-)

diff --git a/pkg/controllers/ingress_controller.go b/pkg/controllers/ingress_controller.go
index f85572c..ef048a7 100644
--- a/pkg/controllers/ingress_controller.go
+++ b/pkg/controllers/ingress_controller.go
@@ -89,6 +89,14 @@ func (r *IngressReconciler) ingressAnnotationMatchFilter(ingress netv1.Ingress)
 	return r.ingressHasAnnotationKeyValue(ingress, r.AnnotationFilter.key, r.AnnotationFilter.value)
 }
 
+func (r *IngressReconciler) listFilteredIngressHosts(ingress *netv1.Ingress) []string {
+	hosts := []string{}
+	for _, rule := range r.filterIngressRulesByHost(ingress.Spec.Rules) {
+		hosts = append(hosts, rule.Host)
+	}
+	return hosts
+}
+
 func (r *IngressReconciler) filterIngressRulesByHost(rules []netv1.IngressRule) []netv1.IngressRule {
 	rulesToBind := []netv1.IngressRule{}
 	for _, rule := range rules {
@@ -192,18 +200,24 @@ func (r *IngressReconciler) newDnsEndpoint(ctx context.Context, dnsEndpoint *ext
 		desiredWeight = 0
 	}
 	dnsEndpoint.Spec = externaldnsk8siov1alpha1.DNSEndpointSpec{Endpoints: []*externaldnsk8siov1alpha1.Endpoint{}}
-	for _, rule := range r.filterIngressRulesByHost(ingress.Spec.Rules) {
 
-		ep := &externaldnsk8siov1alpha1.Endpoint{
-			DNSName:       rule.Host,
-			RecordType:    "CNAME",
-			SetIdentifier: r.ClusterName,
-		}
-		r.addIngressTargetsToEndpoint(ep, ingress)
+	dnsNames := r.listFilteredIngressHosts(&ingress)
 
-		setEndpointProviderSpecificProperty(ep, WeightProperty, strconv.FormatUint(uint64(desiredWeight), 10))
-		setGlobalHealthCheckID(ep)
-		dnsEndpoint.Spec.Endpoints = append(dnsEndpoint.Spec.Endpoints, ep)
+	if len(ingress.Status.LoadBalancer.Ingress) > 0 {
+		for _, dnsName := range dnsNames {
+
+			ep := &externaldnsk8siov1alpha1.Endpoint{
+				DNSName:       dnsName,
+				RecordType:    "CNAME",
+				SetIdentifier: r.ClusterName,
+			}
+			r.addIngressTargetsToEndpoint(ep, ingress)
+
+			setEndpointProviderSpecificProperty(ep, WeightProperty, strconv.FormatUint(uint64(desiredWeight), 10))
+
+			setGlobalHealthCheckID(ep)
+			dnsEndpoint.Spec.Endpoints = append(dnsEndpoint.Spec.Endpoints, ep)
+		}
 	}
 }
 
diff --git a/pkg/controllers/ingress_controller_test.go b/pkg/controllers/ingress_controller_test.go
index 947df63..fdecb9d 100644
--- a/pkg/controllers/ingress_controller_test.go
+++ b/pkg/controllers/ingress_controller_test.go
@@ -510,3 +510,22 @@ func TestEndpointsHasPods(t *testing.T) {
 
 	assert.False(t, r.endpointsHasPods(MockEndpoints(WithObjectFinalizers[*v1.Endpoints]("test.adevinta.com"), WithObjectDeletionTimestamp[*v1.Endpoints](metav1.Now()))))
 }
+
+func TestListFilteredIngressHosts(t *testing.T) {
+	r := IngressReconciler{
+		BindingDomain: "example.com",
+	}
+	assert.ElementsMatch(
+		t,
+		[]string{"host1.example.com", "example.com"},
+		r.listFilteredIngressHosts(
+			MockIngress(
+				IngressWithRules(
+					NewRule(RuleWithHost("host1.example.com")),
+					NewRule(RuleWithHost("example.com")),
+					NewRule(RuleWithHost("adevinta.com")),
+				),
+			),
+		),
+	)
+}