deployer: Respect GWP overrides for Istio integration (#11006)

Signed-off-by: timflannagan <timflannagan@gmail.com>

Author: timflannagan

internal/kgateway/deployer/deployer_test.go

@@ -1076,12 +1076,10 @@ var _ = Describe("Deployer", func() {
 									Repository: ptr.To("bar"),
 									Tag:        ptr.To("baz"),
 								},
-								Ports: []corev1.ContainerPort{
-									{
-										Name:          "foo",
-										ContainerPort: 80,
-									},
-								},
+								Ports: []corev1.ContainerPort{{
+									Name:          "foo",
+									ContainerPort: 80,
+								}},
 							},
 						},
 					},
@@ -1450,6 +1448,23 @@ var _ = Describe("Deployer", func() {
 				}
 			}
 
+			By("validating the override values are set in the istio container")
+			Expect(istioProxyContainer.Env).To(ContainElement(corev1.EnvVar{
+				Name:      "CA_ADDR",
+				Value:     *inp.overrideGwp.Spec.Kube.Istio.IstioProxyContainer.IstioDiscoveryAddress,
+				ValueFrom: nil,
+			}))
+			Expect(istioProxyContainer.Env).To(ContainElement(corev1.EnvVar{
+				Name:      "ISTIO_META_MESH_ID",
+				Value:     *inp.overrideGwp.Spec.Kube.Istio.IstioProxyContainer.IstioMetaMeshId,
+				ValueFrom: nil,
+			}))
+			Expect(istioProxyContainer.Env).To(ContainElement(corev1.EnvVar{
+				Name:      "ISTIO_META_CLUSTER_ID",
+				Value:     *inp.overrideGwp.Spec.Kube.Istio.IstioProxyContainer.IstioMetaClusterId,
+				ValueFrom: nil,
+			}))
+
 			bootstrapCfg := objs.getEnvoyConfig(defaultNamespace, defaultConfigMapName)
 			clusters := bootstrapCfg.GetStaticResources().GetClusters()
 			Expect(clusters).ToNot(BeNil())

internal/kgateway/deployer/merge.go

@@ -530,7 +530,6 @@ func deepMergeIstioContainer(dst, src *v1alpha1.IstioContainer) *v1alpha1.IstioC
 	if src == nil {
 		return dst
 	}
-
 	if dst == nil {
 		return src
 	}
@@ -543,20 +542,15 @@ func deepMergeIstioContainer(dst, src *v1alpha1.IstioContainer) *v1alpha1.IstioC
 		dst.LogLevel = src.GetLogLevel()
 	}
 
-	// Do not allow per-gateway overrides of these values if they are set in the default
-	// GatewayParameters populated by helm values
-	if dst.GetIstioDiscoveryAddress() == nil {
-		// Doesn't matter if we're overriding empty with empty
+	if src.GetIstioDiscoveryAddress() != nil {
 		dst.IstioDiscoveryAddress = src.GetIstioDiscoveryAddress()
 	}
 
-	if dst.GetIstioMetaMeshId() == nil {
-		// Doesn't matter if we're overriding empty with empty
+	if src.GetIstioMetaMeshId() != nil {
 		dst.IstioMetaMeshId = src.GetIstioMetaMeshId()
 	}
 
-	if dst.GetIstioMetaClusterId() == nil {
-		// Doesn't matter if we're overriding empty with empty
+	if src.GetIstioMetaClusterId() != nil {
 		dst.IstioMetaClusterId = src.GetIstioMetaClusterId()
 	}