[feat i2g]add in-cluster console for model comparison

cmd/lbc-migrate/main.go

@@ -3,14 +3,24 @@ package main
 import (
 	"context"
 	"fmt"
+	"net/http"
 	"os"
+	"os/signal"
+	"syscall"
 
 	"github.com/spf13/cobra"
+	networking "k8s.io/api/networking/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/ingress2gateway"
+	"sigs.k8s.io/aws-load-balancer-controller/pkg/ingress2gateway/console"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/ingress2gateway/reader"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/ingress2gateway/translate"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/ingress2gateway/warnings"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/ingress2gateway/writer"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/client/config"
+	gwv1 "sigs.k8s.io/gateway-api/apis/v1"
 )
 
 const defaultOutputDir = "./gateway-output"
@@ -24,6 +34,8 @@ func main() {
 
 func newRootCommand() *cobra.Command {
 	opts := &ingress2gateway.MigrateOptions{}
+	consoleOpts := &ConsoleOptions{Port: 8080}
+	var consoleMode bool
 
 	cmd := &cobra.Command{
 		Use:   "lbc-migrate",
@@ -32,16 +44,27 @@ func newRootCommand() *cobra.Command {
 resources into Gateway API equivalents (Gateway, HTTPRoute, LoadBalancerConfiguration,
 TargetGroupConfiguration, ListenerRuleConfiguration etc).
 
-Input can come from YAML/JSON files, a directory of manifest files, or a live Kubernetes cluster.`,
+Input can come from YAML/JSON files, a directory of manifest files, or a live Kubernetes cluster.
+
+Use --console to launch a local web UI that compares ingress and gateway dry-run models side by side.`,
 		SilenceUsage: true,
 		RunE: func(cmd *cobra.Command, args []string) error {
+			if consoleMode {
+				return runConsole(cmd.Context(), consoleOpts)
+			}
 			if err := validateFlags(opts); err != nil {
 				return err
 			}
 			return runMigrate(cmd.Context(), opts)
 		},
 	}
 
+	// Console flags
+	cmd.Flags().BoolVar(&consoleMode, "console", false,
+		"Launch the migration console web UI to compare ingress and gateway dry-run models")
+	cmd.Flags().IntVar(&consoleOpts.Port, "port", 8080,
+		"Local port for the console web server (only with --console)")
+
 	// Input flags
 	cmd.Flags().StringSliceVarP(&opts.Files, "file", "f", nil,
 		"Comma-separated input YAML/JSON file paths (e.g. -f file1.yaml,file2.yaml)")
@@ -67,9 +90,10 @@ Input can come from YAML/JSON files, a directory of manifest files, or a live Ku
 	cmd.Flags().StringVar(&opts.Split, "split", ingress2gateway.SplitModeNone,
 		"Split output layout. Empty (default) writes one combined file; 'namespace' writes one file per namespace plus a gatewayclass file for cluster-scoped resources")
 
-	// Dry-run flag
-	cmd.Flags().BoolVar(&opts.DryRun, "dry-run", false,
-		"Add gateway.k8s.aws/dry-run annotation to generated Gateway manifests so LBC previews the generated AWS resources without creating them")
+	// Dry-run flag: default to true so users preview the generated model before
+	// creating real AWS resources. Pass --dry-run=false to opt out.
+	cmd.Flags().BoolVar(&opts.DryRun, "dry-run", true,
+		"Add gateway.k8s.aws/dry-run annotation to generated Gateway manifests so LBC previews the generated AWS resources without creating them. Pass --dry-run=false to generate live Gateway manifests.")
 
 	return cmd
 }
@@ -137,3 +161,49 @@ func runMigrate(ctx context.Context, opts *ingress2gateway.MigrateOptions) error
 
 	return ingress2gateway.Migrate(ctx, *opts, readFunc, translate.Translate, writeFunc)
 }
+
+// ConsoleOptions holds the flags for --console mode.
+type ConsoleOptions struct {
+	Port int
+}
+
+func runConsole(ctx context.Context, opts *ConsoleOptions) error {
+	scheme := runtime.NewScheme()
+	_ = clientgoscheme.AddToScheme(scheme)
+	_ = gwv1.Install(scheme)
+	_ = networking.AddToScheme(scheme)
+
+	restConfig, err := config.GetConfig()
+	if err != nil {
+		return fmt.Errorf("failed to get kubeconfig: %w", err)
+	}
+
+	k8sClient, err := client.New(restConfig, client.Options{Scheme: scheme})
+	if err != nil {
+		return fmt.Errorf("failed to create kubernetes client: %w", err)
+	}
+
+	server := console.NewConsoleServer(k8sClient)
+	addr := fmt.Sprintf("localhost:%d", opts.Port)
+
+	httpServer := &http.Server{
+		Addr:    addr,
+		Handler: server.Handler(),
+	}
+
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		<-sigCh
+		fmt.Fprintln(os.Stderr, "\nShutting down...")
+		httpServer.Shutdown(context.Background())
+	}()
+
+	fmt.Fprintf(os.Stderr, "Console running at http://%s\nPress Ctrl+C to stop.\n", addr)
+
+	if err := httpServer.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+		return fmt.Errorf("failed to start console on %s: %w\nUse --port to specify a different port", addr, err)
+	}
+	return nil
+}