fix: add DestinationRules handling to ListServiceMeshHosts

Author: krutsko

pkg/istio/istio.go

@@ -713,10 +713,6 @@ func (i *Istio) ListServiceMeshHosts(ctx context.Context, namespace string) (str
 	}
 
 	for _, svc := range servicesList.Items {
-		// // Skip system services that are not mesh-relevant
-		// if svc.Namespace == "kube-system" || svc.Namespace == "kube-public" || svc.Namespace == "kube-node-lease" {
-		// 	continue
-		// }
 		hostName := svc.Name
 		k8sServiceHosts = append(k8sServiceHosts, hostName)
 		k8sServiceDetails[hostName] = svc.Namespace
@@ -745,11 +741,29 @@ func (i *Istio) ListServiceMeshHosts(ctx context.Context, namespace string) (str
 		}
 	}
 
+	// Collect DestinationRule hosts
+	var destinationRuleHosts []string
+	var destinationRuleDetails = make(map[string]string)
+
+	// Get DestinationRules from the specified namespace
+	drList, err := i.istioClient.NetworkingV1alpha3().DestinationRules(namespace).List(ctx, metav1.ListOptions{})
+	if err != nil {
+		return "", fmt.Errorf("failed to list destination rules: %w", err)
+	}
+
+	for _, dr := range drList.Items {
+		if dr.Spec.Host != "" {
+			destinationRuleHosts = append(destinationRuleHosts, dr.Spec.Host)
+			destinationRuleDetails[dr.Spec.Host] = dr.Name
+		}
+	}
+
 	// Sort all slices for consistent output
 	sort.Strings(serviceEntryHosts)
 	sort.Strings(k8sServiceHosts)
 	sort.Strings(virtualServiceHosts)
 	sort.Strings(wildcardHosts)
+	sort.Strings(destinationRuleHosts)
 
 	// Build ServiceEntry section
 	result += "ServiceEntries (External to Mesh Services):\n"
@@ -790,10 +804,22 @@ func (i *Istio) ListServiceMeshHosts(ctx context.Context, namespace string) (str
 	}
 	result += "\n"
 
+	// Build DestinationRule section
+	result += "DestinationRule Hosts:\n"
+	if len(destinationRuleHosts) == 0 {
+		result += "  (none found)\n"
+	} else {
+		for _, host := range destinationRuleHosts {
+			result += fmt.Sprintf("  %-30s (DestinationRule: %s)\n", host, destinationRuleDetails[host])
+		}
+	}
+	result += "\n"
+
 	// Build summary
 	result += "Summary:\n"
 	result += fmt.Sprintf("- %d ServiceEntries\n", len(serviceEntryHosts))
 	result += fmt.Sprintf("- %d Kubernetes Services\n", len(k8sServiceHosts))
 	result += fmt.Sprintf("- %d VirtualService Configurations\n", len(virtualServiceHosts))
+	result += fmt.Sprintf("- %d DestinationRule Configurations\n", len(destinationRuleHosts))
 	return result, nil
 }

pkg/istio/service_mesh_hosts_test.go

@@ -132,6 +132,28 @@ func TestListServiceMeshHosts(t *testing.T) {
 		}
 	})
 
+	t.Run("ListServiceMeshHosts shows DestinationRule hosts", func(t *testing.T) {
+		result, err := istio.ListServiceMeshHosts(ctx, "bookinfo")
+		if err != nil {
+			t.Fatalf("Failed to list service mesh hosts: %v", err)
+		}
+
+		// Should contain DestinationRule section
+		if !strings.Contains(result, "DestinationRule Hosts:") {
+			t.Errorf("Expected result to contain 'DestinationRule Hosts:' section")
+		}
+
+		// Should contain DestinationRule host from bookinfo namespace
+		if !strings.Contains(result, "productpage") {
+			t.Errorf("Expected result to contain DestinationRule host 'productpage'")
+		}
+
+		// Should contain DestinationRule name
+		if !strings.Contains(result, "productpage-dr") {
+			t.Errorf("Expected result to contain DestinationRule name 'productpage-dr'")
+		}
+	})
+
 	t.Run("ListServiceMeshHosts provides accurate summary", func(t *testing.T) {
 		result, err := istio.ListServiceMeshHosts(ctx, "production")
 		if err != nil {
@@ -143,6 +165,7 @@ func TestListServiceMeshHosts(t *testing.T) {
 			"ServiceEntries",
 			"Kubernetes Services",
 			"VirtualService Configurations",
+			"DestinationRule Configurations",
 		}
 
 		for _, count := range expectedCounts {