fix: create IPv4 Service with ipFamily IPv4 on dual-stack, IPv6-first cluster

Author: michaelbeaumont

internal/infrastructure/kubernetes/proxy/resource_provider.go

@@ -251,8 +251,10 @@ func (r *ResourceRender) Service() (*corev1.Service, error) {
 	// Set IP family policy and families based on proxy config request
 	ipFamily := r.infra.GetProxyConfig().Spec.IPFamily
 	if ipFamily != nil {
-		// SingleStack+IPv4 is default behavior from K8s and so is omitted
 		switch *ipFamily {
+		case egv1a1.IPv4:
+			serviceSpec.IPFamilies = []corev1.IPFamily{corev1.IPv4Protocol}
+			serviceSpec.IPFamilyPolicy = ptr.To(corev1.IPFamilyPolicySingleStack)
 		case egv1a1.IPv6:
 			serviceSpec.IPFamilies = []corev1.IPFamily{corev1.IPv6Protocol}
 			serviceSpec.IPFamilyPolicy = ptr.To(corev1.IPFamilyPolicySingleStack)

internal/infrastructure/kubernetes/proxy/resource_provider_test.go

@@ -1864,8 +1864,8 @@ func TestIPFamilyPresentInSpec(t *testing.T) {
 		{
 			"ipv4 specified",
 			ptr.To(egv1a1.IPv4),
-			nil,
-			nil,
+			[]corev1.IPFamily{corev1.IPv4Protocol},
+			ptr.To(corev1.IPFamilyPolicySingleStack),
 		},
 		{
 			"ipv6 specified",

internal/infrastructure/kubernetes/proxy/testdata/services/ipv4-singlestack.yaml

@@ -17,6 +17,9 @@ metadata:
     uid: test-owner-reference-uid-for-gatewayclass
 spec:
   externalTrafficPolicy: Local
+  ipFamilies:
+  - IPv4
+  ipFamilyPolicy: SingleStack
   ports:
   - name: EnvoyHTTPPort
     port: 0