From aeb416ac10571de0570294792a84c2d023895064 Mon Sep 17 00:00:00 2001
From: John Howard <howardjohn@google.com>
Date: Thu, 19 Dec 2024 11:53:14 -0800
Subject: [PATCH] Cleanup deadcode in multicluster controller (#54426)

All of this is handled in other parts of the code now so this was dead
---
 pilot/pkg/bootstrap/servicecontroller.go       |  3 ---
 .../kube/controller/multicluster.go            | 18 ++----------------
 .../kube/controller/multicluster_test.go       |  8 ++++----
 3 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/pilot/pkg/bootstrap/servicecontroller.go b/pilot/pkg/bootstrap/servicecontroller.go
index 0b5eda25d291..9f8ecc8a1cdc 100644
--- a/pilot/pkg/bootstrap/servicecontroller.go
+++ b/pilot/pkg/bootstrap/servicecontroller.go
@@ -80,11 +80,8 @@ func (s *Server) initKubeRegistry(args *PilotArgs) (err error) {
 	args.RegistryOptions.KubeOptions.MeshServiceController = s.ServiceController()
 	// pass namespace to k8s service registry
 	kubecontroller.NewMulticluster(args.PodName,
-		s.kubeClient.Kube(),
-		args.RegistryOptions.ClusterRegistriesNamespace,
 		args.RegistryOptions.KubeOptions,
 		s.serviceEntryController,
-		s.configController,
 		s.istiodCertBundleWatcher,
 		args.Revision,
 		s.shouldStartNsController(),
diff --git a/pilot/pkg/serviceregistry/kube/controller/multicluster.go b/pilot/pkg/serviceregistry/kube/controller/multicluster.go
index 925c8594aae1..cc519bb4493b 100644
--- a/pilot/pkg/serviceregistry/kube/controller/multicluster.go
+++ b/pilot/pkg/serviceregistry/kube/controller/multicluster.go
@@ -20,7 +20,6 @@ import (
 
 	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/client-go/kubernetes"
 
 	"istio.io/api/annotation"
 	"istio.io/istio/pilot/pkg/config/kube/crdclient"
@@ -76,13 +75,9 @@ type Multicluster struct {
 	// options to use when creating kube controllers
 	opts Options
 
-	// client for reading remote-secrets to initialize multicluster registries
-	client kubernetes.Interface
-	s      server.Instance
+	s server.Instance
 
 	serviceEntryController *serviceentry.Controller
-	configController       model.ConfigStoreController
-	XDSUpdater             model.XDSUpdater
 
 	clusterLocal model.ClusterLocalProvider
 
@@ -90,19 +85,14 @@ type Multicluster struct {
 	caBundleWatcher   *keycertbundle.Watcher
 	revision          string
 
-	// secretNamespace where we get cluster-access secrets
-	secretNamespace string
-	component       *multicluster.Component[*kubeController]
+	component *multicluster.Component[*kubeController]
 }
 
 // NewMulticluster initializes data structure to store multicluster information
 func NewMulticluster(
 	serverID string,
-	kc kubernetes.Interface,
-	secretNamespace string,
 	opts Options,
 	serviceEntryController *serviceentry.Controller,
-	configController model.ConfigStoreController,
 	caBundleWatcher *keycertbundle.Watcher,
 	revision string,
 	startNsController bool,
@@ -114,14 +104,10 @@ func NewMulticluster(
 		serverID:               serverID,
 		opts:                   opts,
 		serviceEntryController: serviceEntryController,
-		configController:       configController,
 		startNsController:      startNsController,
 		caBundleWatcher:        caBundleWatcher,
 		revision:               revision,
-		XDSUpdater:             opts.XDSUpdater,
 		clusterLocal:           clusterLocal,
-		secretNamespace:        secretNamespace,
-		client:                 kc,
 		s:                      s,
 	}
 	mc.component = multicluster.BuildMultiClusterComponent(controller, func(cluster *multicluster.Cluster) *kubeController {
diff --git a/pilot/pkg/serviceregistry/kube/controller/multicluster_test.go b/pilot/pkg/serviceregistry/kube/controller/multicluster_test.go
index 97655b885754..33ead02e1702 100644
--- a/pilot/pkg/serviceregistry/kube/controller/multicluster_test.go
+++ b/pilot/pkg/serviceregistry/kube/controller/multicluster_test.go
@@ -95,12 +95,12 @@ func Test_KubeSecretController(t *testing.T) {
 	stop := test.NewStop(t)
 	s := server.New()
 	mcc := initController(clientset, testSecretNameSpace, stop)
-	mc := NewMulticluster("pilot-abc-123", clientset.Kube(), testSecretNameSpace, Options{
+	mc := NewMulticluster("pilot-abc-123", Options{
 		ClusterID:             "cluster-1",
 		DomainSuffix:          DomainSuffix,
 		MeshWatcher:           mesh.NewFixedWatcher(&meshconfig.MeshConfig{}),
 		MeshServiceController: mockserviceController,
-	}, nil, nil, nil, "default", false, nil, s, mcc)
+	}, nil, nil, "default", false, nil, s, mcc)
 	assert.NoError(t, mcc.Run(stop))
 	go mockserviceController.Run(stop)
 	clientset.RunAndWait(stop)
@@ -138,12 +138,12 @@ func Test_KubeSecretController_ExternalIstiod_MultipleClusters(t *testing.T) {
 	s := server.New()
 	certWatcher := keycertbundle.NewWatcher()
 	mcc := initController(clientset, testSecretNameSpace, stop)
-	mc := NewMulticluster("pilot-abc-123", clientset.Kube(), testSecretNameSpace, Options{
+	mc := NewMulticluster("pilot-abc-123", Options{
 		ClusterID:             "cluster-1",
 		DomainSuffix:          DomainSuffix,
 		MeshWatcher:           mesh.NewFixedWatcher(&meshconfig.MeshConfig{}),
 		MeshServiceController: mockserviceController,
-	}, nil, nil, certWatcher, "default", false, nil, s, mcc)
+	}, nil, certWatcher, "default", false, nil, s, mcc)
 	assert.NoError(t, mcc.Run(stop))
 	go mockserviceController.Run(stop)
 	clientset.RunAndWait(stop)