Extend GatewayResources to hold Gateway Extension.

* Create a list of unstructured.Unstructured to hold Gateway Extensions.
* Add methods to cast a runtime Object to Unstructured, and print as
  yaml.

Author: sawsa307

cmd/print.go

@@ -25,6 +25,9 @@ import (
 	"github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw"
 	"github.com/samber/lo"
 	"github.com/spf13/cobra"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/serializer/json"
 	"k8s.io/cli-runtime/pkg/genericclioptions"
 	"k8s.io/cli-runtime/pkg/printers"
 	"k8s.io/client-go/tools/clientcmd"
@@ -179,6 +182,17 @@ func (pr *PrintRunner) outputResult(gatewayResources []i2gw.GatewayResources) {
 		}
 	}
 
+	for _, r := range gatewayResources {
+		resourceCount += len(r.GatewayExtensions)
+		for _, gatewayExtension := range r.GatewayExtensions {
+			gatewayExtension := gatewayExtension
+			fmt.Println("---")
+			if err := PrintUnstructuredAsYaml(&gatewayExtension); err != nil {
+				fmt.Printf("# Error printing %s gatewayExtension: %v\n", gatewayExtension.GetName(), err)
+			}
+		}
+	}
+
 	if resourceCount == 0 {
 		msg := "No resources found"
 		if pr.namespaceFilter != "" {
@@ -188,6 +202,34 @@ func (pr *PrintRunner) outputResult(gatewayResources []i2gw.GatewayResources) {
 	}
 }
 
+func CastToUnstructured(obj runtime.Object) (*unstructured.Unstructured, error) {
+	// Convert the Kubernetes object to unstructured.Unstructured
+	unstructuredObj, err := runtime.DefaultUnstructuredConverter.ToUnstructured(obj)
+	if err != nil {
+		return nil, err
+	}
+
+	return &unstructured.Unstructured{Object: unstructuredObj}, nil
+}
+
+func PrintUnstructuredAsYaml(obj *unstructured.Unstructured) error {
+	// Create a YAML serializer
+	serializer := json.NewSerializerWithOptions(json.DefaultMetaFactory, nil, nil,
+		json.SerializerOptions{
+			Yaml:   true,
+			Pretty: true, // Optional: for better readability
+			Strict: true,
+		})
+
+	// Encode the unstructured object to YAML
+	err := serializer.Encode(obj, os.Stdout)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // initializeResourcePrinter assign a specific type of printers.ResourcePrinter
 // based on the outputFormat of the printRunner struct.
 func (pr *PrintRunner) initializeResourcePrinter() error {

pkg/i2gw/provider.go

@@ -21,6 +21,7 @@ import (
 	"sync"
 
 	networkingv1 "k8s.io/api/networking/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	"sigs.k8s.io/controller-runtime/pkg/client"
@@ -88,7 +89,8 @@ type ProviderImplementationSpecificOptions struct {
 	ToImplementationSpecificHTTPPathTypeMatch ImplementationSpecificHTTPPathTypeMatchConverter
 }
 
-// GatewayResources contains all Gateway-API objects.
+// GatewayResources contains all Gateway-API objects and provider Gateway
+// extensions.
 type GatewayResources struct {
 	Gateways       map[types.NamespacedName]gatewayv1.Gateway
 	GatewayClasses map[types.NamespacedName]gatewayv1.GatewayClass
@@ -99,6 +101,8 @@ type GatewayResources struct {
 	UDPRoutes  map[types.NamespacedName]gatewayv1alpha2.UDPRoute
 
 	ReferenceGrants map[types.NamespacedName]gatewayv1beta1.ReferenceGrant
+
+	GatewayExtensions map[types.NamespacedName]unstructured.Unstructured
 }
 
 // IR contains all Gateway-API objects, and Intermediate Representation(IR) to