CVE-2022-41354

@@ -165,7 +165,9 @@ func NewApplicationCreateCommand(clientOpts *argocdclient.ClientOptions) *cobra.
 
 				// Get app before creating to see if it is being updated or no change
 				existing, err := appIf.Get(ctx, &applicationpkg.ApplicationQuery{Name: &app.Name})
-				if grpc.UnwrapGRPCStatus(err).Code() != codes.NotFound {
+				unwrappedError := grpc.UnwrapGRPCStatus(err).Code()
+				// As part of the fix for CVE-2022-41354, the API will return Permission Denied when an app does not exist.
+				if unwrappedError != codes.NotFound && unwrappedError != codes.PermissionDenied {
 					errors.CheckError(err)
 				}
 

@@ -184,3 +184,16 @@ This note is just for clarity. No action is required.
 
 We [expected](../upgrading/2.3-2.4.md#enable-logs-rbac-enforcement) to enable logs RBAC enforcement by default in 2.5.
 We have decided not to do that in the 2.x series due to disruption for users of [Project Roles](../../user-guide/projects.md#project-roles).
+
+## `argocd app create` for old CLI versions fails with API version >=2.5.16
+
+Starting with Argo CD 2.5.16, the API returns `PermissionDenied` instead of `NotFound` for Application `GET` requests if
+the Application does not exist.
+
+The Argo CD CLI before versions starting with version 2.5.0-rc1 and before versions 2.5.16 and 2.6.7 does a `GET` 
+request before the `POST` request in `argocd app create`. The command does not gracefully handle the `PermissionDenied` 
+response and will therefore fail to create/update the Application.
+
+To solve the issue, upgrade the CLI to at least 2.5.16, or 2.6.7.
+
+CLIs older than 2.5.0-rc1 are unaffected.

@@ -81,3 +81,17 @@ name. Argo CD v2.6 introduces support for specifying sidecar plugins by name.
 
 Removal of argocd-cm plugin support has been delayed until 2.7 to provide a transition time for users who need to 
 specify plugins by name. 
+
+## `argocd app create` for old CLI versions fails with API version >=2.6.7
+
+Starting with Argo CD 2.6.7, the API returns `PermissionDenied` instead of `NotFound` for Application `GET` requests if
+the Application does not exist.
+
+The Argo CD CLI before versions starting with version 2.5.0-rc1 and before versions 2.5.16 and 2.6.7 does a `GET`
+request before the `POST` request in `argocd app create`. The command does not gracefully handle the `PermissionDenied`
+response and will therefore fail to create/update the Application.
+
+To solve the issue, upgrade the CLI to at least 2.5.16, or 2.6.7.
+
+CLIs older than 2.5.0-rc1 are unaffected.
+

@@ -0,0 +1,167 @@
+// Code generated by mockery v2.13.1. DO NOT EDIT.
+
+package mocks
+
+import (
+	context "context"
+
+	apiclient "github.com/argoproj/argo-cd/v2/reposerver/apiclient"
+
+	metadata "google.golang.org/grpc/metadata"
+
+	mock "github.com/stretchr/testify/mock"
+)
+
+// RepoServerService_GenerateManifestWithFilesClient is an autogenerated mock type for the RepoServerService_GenerateManifestWithFilesClient type
+type RepoServerService_GenerateManifestWithFilesClient struct {
+	mock.Mock
+}
+
+// CloseAndRecv provides a mock function with given fields:
+func (_m *RepoServerService_GenerateManifestWithFilesClient) CloseAndRecv() (*apiclient.ManifestResponse, error) {
+	ret := _m.Called()
+
+	var r0 *apiclient.ManifestResponse
+	if rf, ok := ret.Get(0).(func() *apiclient.ManifestResponse); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(*apiclient.ManifestResponse)
+		}
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func() error); ok {
+		r1 = rf()
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// CloseSend provides a mock function with given fields:
+func (_m *RepoServerService_GenerateManifestWithFilesClient) CloseSend() error {
+	ret := _m.Called()
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func() error); ok {
+		r0 = rf()
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
+// Context provides a mock function with given fields:
+func (_m *RepoServerService_GenerateManifestWithFilesClient) Context() context.Context {
+	ret := _m.Called()
+
+	var r0 context.Context
+	if rf, ok := ret.Get(0).(func() context.Context); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(context.Context)
+		}
+	}
+
+	return r0
+}
+
+// Header provides a mock function with given fields:
+func (_m *RepoServerService_GenerateManifestWithFilesClient) Header() (metadata.MD, error) {
+	ret := _m.Called()
+
+	var r0 metadata.MD
+	if rf, ok := ret.Get(0).(func() metadata.MD); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(metadata.MD)
+		}
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func() error); ok {
+		r1 = rf()
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// RecvMsg provides a mock function with given fields: m
+func (_m *RepoServerService_GenerateManifestWithFilesClient) RecvMsg(m interface{}) error {
+	ret := _m.Called(m)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(interface{}) error); ok {
+		r0 = rf(m)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
+// Send provides a mock function with given fields: _a0
+func (_m *RepoServerService_GenerateManifestWithFilesClient) Send(_a0 *apiclient.ManifestRequestWithFiles) error {
+	ret := _m.Called(_a0)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(*apiclient.ManifestRequestWithFiles) error); ok {
+		r0 = rf(_a0)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
+// SendMsg provides a mock function with given fields: m
+func (_m *RepoServerService_GenerateManifestWithFilesClient) SendMsg(m interface{}) error {
+	ret := _m.Called(m)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(interface{}) error); ok {
+		r0 = rf(m)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
+// Trailer provides a mock function with given fields:
+func (_m *RepoServerService_GenerateManifestWithFilesClient) Trailer() metadata.MD {
+	ret := _m.Called()
+
+	var r0 metadata.MD
+	if rf, ok := ret.Get(0).(func() metadata.MD); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(metadata.MD)
+		}
+	}
+
+	return r0
+}
+
+type mockConstructorTestingTNewRepoServerService_GenerateManifestWithFilesClient interface {
+	mock.TestingT
+	Cleanup(func())
+}
+
+// NewRepoServerService_GenerateManifestWithFilesClient creates a new instance of RepoServerService_GenerateManifestWithFilesClient. It also registers a testing interface on the mock and a cleanup function to assert the mocks expectations.
+func NewRepoServerService_GenerateManifestWithFilesClient(t mockConstructorTestingTNewRepoServerService_GenerateManifestWithFilesClient) *RepoServerService_GenerateManifestWithFilesClient {
+	mock := &RepoServerService_GenerateManifestWithFilesClient{}
+	mock.Mock.Test(t)
+
+	t.Cleanup(func() { mock.AssertExpectations(t) })
+
+	return mock
+}

@@ -68,7 +68,8 @@ const (
 )
 
 var (
-	watchAPIBufferSize = env.ParseNumFromEnv(argocommon.EnvWatchAPIBufferSize, 1000, 0, math.MaxInt32)
+	watchAPIBufferSize  = env.ParseNumFromEnv(argocommon.EnvWatchAPIBufferSize, 1000, 0, math.MaxInt32)
+	permissionDeniedErr = status.Error(codes.PermissionDenied, "permission denied")
 )
 
 // Server provides an Application service
@@ -78,7 +79,7 @@ type Server struct {
 	appclientset      appclientset.Interface
 	appLister         applisters.ApplicationLister
 	appInformer       cache.SharedIndexInformer
-	appBroadcaster    *broadcasterHandler
+	appBroadcaster    Broadcaster
 	repoClientset     apiclient.Clientset
 	kubectl           kube.Kubectl
 	db                db.ArgoDB
@@ -98,6 +99,7 @@ func NewServer(
 	appclientset appclientset.Interface,
 	appLister applisters.ApplicationLister,
 	appInformer cache.SharedIndexInformer,
+	appBroadcaster Broadcaster,
 	repoClientset apiclient.Clientset,
 	cache *servercache.Cache,
 	kubectl kube.Kubectl,
@@ -108,7 +110,9 @@ func NewServer(
 	projInformer cache.SharedIndexInformer,
 	enabledNamespaces []string,
 ) (application.ApplicationServiceServer, AppResourceTreeFn) {
-	appBroadcaster := &broadcasterHandler{}
+	if appBroadcaster == nil {
+		appBroadcaster = &broadcasterHandler{}
+	}
 	appInformer.AddEventHandler(appBroadcaster)
 	s := &Server{
 		ns:                namespace,
@@ -131,6 +135,61 @@ func NewServer(
 	return s, s.getAppResources
 }
 
+// getAppEnforceRBAC gets the Application with the given name in the given namespace. If no namespace is
+// specified, the Application is fetched from the default namespace (the one in which the API server is running).
+//
+// If the Application does not exist, then we have no way of determining if the user would have had access to get that
+// Application. Verifying access requires knowing the Application's name, namespace, and project. The user may specify,
+// at minimum, the Application name.
+//
+// So to prevent a malicious user from inferring the existence or absense of the Application or namespace, we respond
+// "permission denied" if the Application does not exist.
+func (s *Server) getAppEnforceRBAC(ctx context.Context, action, namespace, name string, getApp func() (*appv1.Application, error)) (*appv1.Application, error) {
+	logCtx := log.WithFields(map[string]interface{}{
+		"application": name,
+		"namespace":   namespace,
+	})
+	a, err := getApp()
+	if err != nil {
+		if apierr.IsNotFound(err) {
+			logCtx.Warn("application does not exist")
+			return nil, permissionDeniedErr
+		}
+		logCtx.Errorf("failed to get application: %s", err)
+		return nil, permissionDeniedErr
+	}
+	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, action, a.RBACName(s.ns)); err != nil {
+		logCtx.WithFields(map[string]interface{}{
+			"project":                a.Spec.Project,
+			argocommon.SecurityField: argocommon.SecurityMedium,
+		}).Warnf("user tried to %s application which they do not have access to: %s", action, err)
+		return nil, permissionDeniedErr
+	}
+	return a, nil
+}
+
+// getApplicationEnforceRBACInformer uses an informer to get an Application. If the app does not exist, permission is
+// denied, or any other error occurs when getting the app, we return a permission denied error to obscure any sensitive
+// information.
+func (s *Server) getApplicationEnforceRBACInformer(ctx context.Context, action, namespace, name string) (*appv1.Application, error) {
+	namespaceOrDefault := s.appNamespaceOrDefault(namespace)
+	return s.getAppEnforceRBAC(ctx, action, namespaceOrDefault, name, func() (*appv1.Application, error) {
+		return s.appLister.Applications(namespaceOrDefault).Get(name)
+	})
+}
+
+// getApplicationEnforceRBACClient uses a client to get an Application. If the app does not exist, permission is denied,
+// or any other error occurs when getting the app, we return a permission denied error to obscure any sensitive
+// information.
+func (s *Server) getApplicationEnforceRBACClient(ctx context.Context, action, namespace, name, resourceVersion string) (*appv1.Application, error) {
+	namespaceOrDefault := s.appNamespaceOrDefault(namespace)
+	return s.getAppEnforceRBAC(ctx, action, namespaceOrDefault, name, func() (*appv1.Application, error) {
+		return s.appclientset.ArgoprojV1alpha1().Applications(namespaceOrDefault).Get(ctx, name, metav1.GetOptions{
+			ResourceVersion: resourceVersion,
+		})
+	})
+}
+
 // List returns list of applications
 func (s *Server) List(ctx context.Context, q *application.ApplicationQuery) (*appv1.ApplicationList, error) {
 	selector, err := labels.Parse(q.GetSelector())
@@ -318,13 +377,8 @@ func (s *Server) GetManifests(ctx context.Context, q *application.ApplicationMan
 	if q.Name == nil || *q.Name == "" {
 		return nil, fmt.Errorf("invalid request: application name is missing")
 	}
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetName())
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -426,14 +480,8 @@ func (s *Server) GetManifestsWithFiles(stream application.ApplicationService_Get
 		return fmt.Errorf("invalid request: application name is missing")
 	}
 
-	appName := query.GetName()
-	appNs := s.appNamespaceOrDefault(query.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
-
+	a, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, query.GetAppNamespace(), query.GetName())
 	if err != nil {
-		return fmt.Errorf("error getting application: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return err
 	}
 
@@ -538,14 +586,8 @@ func (s *Server) Get(ctx context.Context, q *application.ApplicationQuery) (*app
 	// We must use a client Get instead of an informer Get, because it's common to call Get immediately
 	// following a Watch (which is not yet powered by an informer), and the Get must reflect what was
 	// previously seen by the client.
-	a, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{
-		ResourceVersion: q.GetResourceVersion(),
-	})
-
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, appNs, appName, q.GetResourceVersion())
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -627,13 +669,8 @@ func (s *Server) Get(ctx context.Context, q *application.ApplicationQuery) (*app
 
 // ListResourceEvents returns a list of event resources
 func (s *Server) ListResourceEvents(ctx context.Context, q *application.ApplicationResourceEventsQuery) (*v1.EventList, error) {
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetName())
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -694,13 +731,13 @@ func (s *Server) ListResourceEvents(ctx context.Context, q *application.Applicat
 	return list, nil
 }
 
-func (s *Server) validateAndUpdateApp(ctx context.Context, newApp *appv1.Application, merge bool, validate bool) (*appv1.Application, error) {
+func (s *Server) validateAndUpdateApp(ctx context.Context, newApp *appv1.Application, merge bool, validate bool, action string) (*appv1.Application, error) {
 	s.projectLock.RLock(newApp.Spec.GetProject())
 	defer s.projectLock.RUnlock(newApp.Spec.GetProject())
 
-	app, err := s.appclientset.ArgoprojV1alpha1().Applications(newApp.Namespace).Get(ctx, newApp.Name, metav1.GetOptions{})
+	app, err := s.getApplicationEnforceRBACClient(ctx, action, newApp.Namespace, newApp.Name, "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
+		return nil, err
 	}
 
 	err = s.validateAndNormalizeApp(ctx, newApp, validate)
@@ -807,21 +844,16 @@ func (s *Server) Update(ctx context.Context, q *application.ApplicationUpdateReq
 	if q.Validate != nil {
 		validate = *q.Validate
 	}
-	return s.validateAndUpdateApp(ctx, q.Application, false, validate)
+	return s.validateAndUpdateApp(ctx, q.Application, false, validate, rbacpolicy.ActionUpdate)
 }
 
 // UpdateSpec updates an application spec and filters out any invalid parameter overrides
 func (s *Server) UpdateSpec(ctx context.Context, q *application.ApplicationUpdateSpecRequest) (*appv1.ApplicationSpec, error) {
 	if q.GetSpec() == nil {
 		return nil, fmt.Errorf("error updating application spec: spec is nil in request")
 	}
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionUpdate, q.GetAppNamespace(), q.GetName(), "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -830,7 +862,7 @@ func (s *Server) UpdateSpec(ctx context.Context, q *application.ApplicationUpdat
 	if q.Validate != nil {
 		validate = *q.Validate
 	}
-	a, err = s.validateAndUpdateApp(ctx, a, false, validate)
+	a, err = s.validateAndUpdateApp(ctx, a, false, validate, rbacpolicy.ActionUpdate)
 	if err != nil {
 		return nil, fmt.Errorf("error validating and updating app: %w", err)
 	}
@@ -839,11 +871,9 @@ func (s *Server) UpdateSpec(ctx context.Context, q *application.ApplicationUpdat
 
 // Patch patches an application
 func (s *Server) Patch(ctx context.Context, q *application.ApplicationPatchRequest) (*appv1.Application, error) {
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	app, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{})
+	app, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetName(), "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
+		return nil, err
 	}
 
 	if err = s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, app.RBACName(s.ns)); err != nil {
@@ -881,16 +911,16 @@ func (s *Server) Patch(ctx context.Context, q *application.ApplicationPatchReque
 	if err != nil {
 		return nil, fmt.Errorf("error unmarshaling patched app: %w", err)
 	}
-	return s.validateAndUpdateApp(ctx, newApp, false, true)
+	return s.validateAndUpdateApp(ctx, newApp, false, true, rbacpolicy.ActionUpdate)
 }
 
 // Delete removes an application and all associated resources
 func (s *Server) Delete(ctx context.Context, q *application.ApplicationDeleteRequest) (*application.ApplicationResponse, error) {
 	appName := q.GetName()
 	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, appNs, appName, "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
+		return nil, err
 	}
 
 	s.projectLock.RLock(a.Spec.Project)
@@ -1034,7 +1064,9 @@ func (s *Server) validateAndNormalizeApp(ctx context.Context, app *appv1.Applica
 	proj, err := argo.GetAppProject(app, applisters.NewAppProjectLister(s.projInformer.GetIndexer()), s.ns, s.settingsMgr, s.db, ctx)
 	if err != nil {
 		if apierr.IsNotFound(err) {
-			return status.Errorf(codes.InvalidArgument, "application references project %s which does not exist", app.Spec.Project)
+			// Offer no hint that the project does not exist.
+			log.Warnf("User attempted to create/update application in non-existent project %q", app.Spec.Project)
+			return permissionDeniedErr
 		}
 		return fmt.Errorf("error getting application's project: %w", err)
 	}
@@ -1138,22 +1170,16 @@ func (s *Server) getAppResources(ctx context.Context, a *appv1.Application) (*ap
 		return s.cache.GetAppResourcesTree(a.InstanceName(s.ns), &tree)
 	})
 	if err != nil {
-		return &tree, fmt.Errorf("error getting cached app state: %w", err)
+		return &tree, fmt.Errorf("error getting cached app resource tree: %w", err)
 	}
 	return &tree, nil
 }
 
 func (s *Server) getAppLiveResource(ctx context.Context, action string, q *application.ApplicationResourceRequest) (*appv1.ResourceNode, *rest.Config, *appv1.Application, error) {
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ctx, action, q.GetAppNamespace(), q.GetName())
 	if err != nil {
-		return nil, nil, nil, fmt.Errorf("error getting app by name: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, action, a.RBACName(s.ns)); err != nil {
 		return nil, nil, nil, err
 	}
-
 	tree, err := s.getAppResources(ctx, a)
 	if err != nil {
 		return nil, nil, nil, fmt.Errorf("error getting app resources: %w", err)
@@ -1173,7 +1199,7 @@ func (s *Server) getAppLiveResource(ctx context.Context, action string, q *appli
 func (s *Server) GetResource(ctx context.Context, q *application.ApplicationResourceRequest) (*application.ApplicationResourceResponse, error) {
 	res, config, _, err := s.getAppLiveResource(ctx, rbacpolicy.ActionGet, q)
 	if err != nil {
-		return nil, fmt.Errorf("error getting app live resource: %w", err)
+		return nil, err
 	}
 
 	// make sure to use specified resource version if provided
@@ -1220,9 +1246,6 @@ func (s *Server) PatchResource(ctx context.Context, q *application.ApplicationRe
 	}
 	res, config, a, err := s.getAppLiveResource(ctx, rbacpolicy.ActionUpdate, resourceRequest)
 	if err != nil {
-		return nil, fmt.Errorf("error getting app live resource: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionUpdate, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -1234,6 +1257,9 @@ func (s *Server) PatchResource(ctx context.Context, q *application.ApplicationRe
 		}
 		return nil, fmt.Errorf("error patching resource: %w", err)
 	}
+	if manifest == nil {
+		return nil, fmt.Errorf("failed to patch resource: manifest was nil")
+	}
 	manifest, err = replaceSecretValues(manifest)
 	if err != nil {
 		return nil, fmt.Errorf("error replacing secret values: %w", err)
@@ -1262,9 +1288,6 @@ func (s *Server) DeleteResource(ctx context.Context, q *application.ApplicationR
 	}
 	res, config, a, err := s.getAppLiveResource(ctx, rbacpolicy.ActionDelete, resourceRequest)
 	if err != nil {
-		return nil, fmt.Errorf("error getting live resource for delete: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionDelete, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 	var deleteOption metav1.DeleteOptions
@@ -1288,28 +1311,17 @@ func (s *Server) DeleteResource(ctx context.Context, q *application.ApplicationR
 }
 
 func (s *Server) ResourceTree(ctx context.Context, q *application.ResourcesQuery) (*appv1.ApplicationTree, error) {
-	appName := q.GetApplicationName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetApplicationName())
 	if err != nil {
-		return nil, fmt.Errorf("error getting application by name: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
 	return s.getAppResources(ctx, a)
 }
 
 func (s *Server) WatchResourceTree(q *application.ResourcesQuery, ws application.ApplicationService_WatchResourceTreeServer) error {
-	appName := q.GetApplicationName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	_, err := s.getApplicationEnforceRBACInformer(ws.Context(), rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetApplicationName())
 	if err != nil {
-		return fmt.Errorf("error getting application by name: %w", err)
-	}
-
-	if err := s.enf.EnforceErr(ws.Context().Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return err
 	}
 
@@ -1324,13 +1336,8 @@ func (s *Server) WatchResourceTree(q *application.ResourcesQuery, ws application
 }
 
 func (s *Server) RevisionMetadata(ctx context.Context, q *application.RevisionMetadataQuery) (*appv1.RevisionMetadata, error) {
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetName())
 	if err != nil {
-		return nil, fmt.Errorf("error getting app by name: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -1365,22 +1372,17 @@ func isMatchingResource(q *application.ResourcesQuery, key kube.ResourceKey) boo
 }
 
 func (s *Server) ManagedResources(ctx context.Context, q *application.ResourcesQuery) (*application.ManagedResourcesResponse, error) {
-	appName := q.GetApplicationName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetApplicationName())
 	if err != nil {
-		return nil, fmt.Errorf("error getting application: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
-		return nil, fmt.Errorf("error verifying rbac: %w", err)
+		return nil, err
 	}
 
 	items := make([]*appv1.ResourceDiff, 0)
 	err = s.getCachedAppState(ctx, a, func() error {
 		return s.cache.GetAppManagedResources(a.InstanceName(s.ns), &items)
 	})
 	if err != nil {
-		return nil, fmt.Errorf("error getting cached app state: %w", err)
+		return nil, fmt.Errorf("error getting cached app managed resources: %w", err)
 	}
 	res := &application.ManagedResourcesResponse{}
 	for i := range items {
@@ -1427,14 +1429,8 @@ func (s *Server) PodLogs(q *application.ApplicationPodLogsQuery, ws application.
 		}
 	}
 
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	a, err := s.appLister.Applications(appNs).Get(appName)
+	a, err := s.getApplicationEnforceRBACInformer(ws.Context(), rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetName())
 	if err != nil {
-		return fmt.Errorf("error getting application by name: %w", err)
-	}
-
-	if err := s.enf.EnforceErr(ws.Context().Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return err
 	}
 
@@ -1625,12 +1621,9 @@ func isTheSelectedOne(currentNode *appv1.ResourceNode, q *application.Applicatio
 
 // Sync syncs an application to its target state
 func (s *Server) Sync(ctx context.Context, syncReq *application.ApplicationSyncRequest) (*appv1.Application, error) {
-	appName := syncReq.GetName()
-	appNs := s.appNamespaceOrDefault(syncReq.GetAppNamespace())
-	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
-	a, err := appIf.Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, syncReq.GetAppNamespace(), syncReq.GetName(), "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application by name: %w", err)
+		return nil, err
 	}
 
 	proj, err := argo.GetAppProject(a, applisters.NewAppProjectLister(s.projInformer.GetIndexer()), s.ns, s.settingsMgr, s.db, ctx)
@@ -1717,6 +1710,9 @@ func (s *Server) Sync(ctx context.Context, syncReq *application.ApplicationSyncR
 		op.Retry = *retry
 	}
 
+	appName := syncReq.GetName()
+	appNs := s.appNamespaceOrDefault(syncReq.GetAppNamespace())
+	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
 	a, err = argo.SetAppOperation(appIf, appName, &op)
 	if err != nil {
 		return nil, fmt.Errorf("error setting app operation: %w", err)
@@ -1734,14 +1730,8 @@ func (s *Server) Sync(ctx context.Context, syncReq *application.ApplicationSyncR
 }
 
 func (s *Server) Rollback(ctx context.Context, rollbackReq *application.ApplicationRollbackRequest) (*appv1.Application, error) {
-	appName := rollbackReq.GetName()
-	appNs := s.appNamespaceOrDefault(rollbackReq.GetAppNamespace())
-	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
-	a, err := appIf.Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionSync, rollbackReq.GetAppNamespace(), rollbackReq.GetName(), "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application by name: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionSync, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -1787,6 +1777,9 @@ func (s *Server) Rollback(ctx context.Context, rollbackReq *application.Applicat
 		},
 		InitiatedBy: appv1.OperationInitiator{Username: session.Username(ctx)},
 	}
+	appName := rollbackReq.GetName()
+	appNs := s.appNamespaceOrDefault(rollbackReq.GetAppNamespace())
+	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
 	a, err = argo.SetAppOperation(appIf, appName, &op)
 	if err != nil {
 		return nil, fmt.Errorf("error setting app operation: %w", err)
@@ -1796,24 +1789,9 @@ func (s *Server) Rollback(ctx context.Context, rollbackReq *application.Applicat
 }
 
 func (s *Server) ListLinks(ctx context.Context, req *application.ListAppLinksRequest) (*application.LinksResponse, error) {
-	appName := req.GetName()
-	appNs := s.appNamespaceOrDefault(req.GetNamespace())
-
-	a, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionSync, req.GetNamespace(), req.GetName(), "")
 	if err != nil {
-		log.WithFields(map[string]interface{}{
-			"application": appName,
-			"ns":          appNs,
-		}).Errorf("failed to get application, error=%v", err.Error())
-		return nil, fmt.Errorf("error getting application")
-	}
-
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
-		log.WithFields(map[string]interface{}{
-			"application": appName,
-			"ns":          appNs,
-		}).Warnf("unauthorized access to app, error=%v", err.Error())
-		return nil, fmt.Errorf("error getting application")
+		return nil, err
 	}
 
 	obj, err := kube.ToUnstructured(a)
@@ -1965,11 +1943,8 @@ func (s *Server) resolveRevision(ctx context.Context, app *appv1.Application, sy
 func (s *Server) TerminateOperation(ctx context.Context, termOpReq *application.OperationTerminateRequest) (*application.OperationTerminateResponse, error) {
 	appName := termOpReq.GetName()
 	appNs := s.appNamespaceOrDefault(termOpReq.GetAppNamespace())
-	a, err := s.appclientset.ArgoprojV1alpha1().Applications(appNs).Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionSync, appNs, appName, "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application by name: %w", err)
-	}
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionSync, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 
@@ -2041,10 +2016,9 @@ func (s *Server) ListResourceActions(ctx context.Context, q *application.Applica
 
 func (s *Server) getUnstructuredLiveResourceOrApp(ctx context.Context, rbacRequest string, q *application.ApplicationResourceRequest) (obj *unstructured.Unstructured, res *appv1.ResourceNode, app *appv1.Application, config *rest.Config, err error) {
 	if q.GetKind() == "Application" && q.GetGroup() == "argoproj.io" && q.GetName() == q.GetResourceName() {
-		namespace := s.appNamespaceOrDefault(q.GetAppNamespace())
-		app, err = s.appLister.Applications(namespace).Get(q.GetName())
+		app, err = s.getApplicationEnforceRBACInformer(ctx, rbacRequest, q.GetAppNamespace(), q.GetName())
 		if err != nil {
-			return nil, nil, nil, nil, fmt.Errorf("error getting app by name: %w", err)
+			return nil, nil, nil, nil, err
 		}
 		if err = s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacRequest, app.RBACName(s.ns)); err != nil {
 			return nil, nil, nil, nil, err
@@ -2057,7 +2031,7 @@ func (s *Server) getUnstructuredLiveResourceOrApp(ctx context.Context, rbacReque
 	} else {
 		res, config, app, err = s.getAppLiveResource(ctx, rbacRequest, q)
 		if err != nil {
-			return nil, nil, nil, nil, fmt.Errorf("error getting app live resource: %w", err)
+			return nil, nil, nil, nil, err
 		}
 		obj, err = s.kubectl.GetResource(ctx, config, res.GroupKindVersion(), res.Name, res.Namespace)
 	}
@@ -2227,15 +2201,8 @@ func (s *Server) plugins() ([]*appv1.ConfigManagementPlugin, error) {
 }
 
 func (s *Server) GetApplicationSyncWindows(ctx context.Context, q *application.ApplicationSyncWindowsQuery) (*application.ApplicationSyncWindowsResponse, error) {
-	appName := q.GetName()
-	appNs := s.appNamespaceOrDefault(q.GetAppNamespace())
-	appIf := s.appclientset.ArgoprojV1alpha1().Applications(appNs)
-	a, err := appIf.Get(ctx, appName, metav1.GetOptions{})
+	a, err := s.getApplicationEnforceRBACClient(ctx, rbacpolicy.ActionGet, q.GetAppNamespace(), q.GetName(), "")
 	if err != nil {
-		return nil, fmt.Errorf("error getting application by name: %w", err)
-	}
-
-	if err := s.enf.EnforceErr(ctx.Value("claims"), rbacpolicy.ResourceApplications, rbacpolicy.ActionGet, a.RBACName(s.ns)); err != nil {
 		return nil, err
 	}
 

@@ -4,12 +4,15 @@ import (
 	"context"
 	coreerrors "errors"
 	"fmt"
+	"io"
+	"strconv"
 	"sync/atomic"
 	"testing"
 	"time"
 
 	"github.com/argoproj/gitops-engine/pkg/health"
 	synccommon "github.com/argoproj/gitops-engine/pkg/sync/common"
+	"github.com/argoproj/gitops-engine/pkg/utils/kube"
 	"github.com/argoproj/gitops-engine/pkg/utils/kube/kubetest"
 	"github.com/argoproj/pkg/sync"
 	"github.com/ghodss/yaml"
@@ -18,13 +21,17 @@ import (
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/status"
+	k8sappsv1 "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
-	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/watch"
 	"k8s.io/client-go/kubernetes/fake"
+	"k8s.io/client-go/rest"
 	kubetesting "k8s.io/client-go/testing"
 	k8scache "k8s.io/client-go/tools/cache"
 	"k8s.io/utils/pointer"
@@ -36,6 +43,7 @@ import (
 	appinformer "github.com/argoproj/argo-cd/v2/pkg/client/informers/externalversions"
 	"github.com/argoproj/argo-cd/v2/reposerver/apiclient"
 	"github.com/argoproj/argo-cd/v2/reposerver/apiclient/mocks"
+	appmocks "github.com/argoproj/argo-cd/v2/server/application/mocks"
 	servercache "github.com/argoproj/argo-cd/v2/server/cache"
 	"github.com/argoproj/argo-cd/v2/server/rbacpolicy"
 	"github.com/argoproj/argo-cd/v2/test"
@@ -98,6 +106,11 @@ func fakeRepoServerClient(isHelm bool) *mocks.RepoServerServiceClient {
 	mockRepoServiceClient.On("GenerateManifest", mock.Anything, mock.Anything).Return(&apiclient.ManifestResponse{}, nil)
 	mockRepoServiceClient.On("GetAppDetails", mock.Anything, mock.Anything).Return(&apiclient.RepoAppDetailsResponse{}, nil)
 	mockRepoServiceClient.On("TestRepository", mock.Anything, mock.Anything).Return(&apiclient.TestRepositoryResponse{}, nil)
+	mockRepoServiceClient.On("GetRevisionMetadata", mock.Anything, mock.Anything).Return(&appsv1.RevisionMetadata{}, nil)
+	mockWithFilesClient := &mocks.RepoServerService_GenerateManifestWithFilesClient{}
+	mockWithFilesClient.On("Send", mock.Anything).Return(nil)
+	mockWithFilesClient.On("CloseAndRecv").Return(&apiclient.ManifestResponse{}, nil)
+	mockRepoServiceClient.On("GenerateManifestWithFiles", mock.Anything, mock.Anything).Return(mockWithFilesClient, nil)
 
 	if isHelm {
 		mockRepoServiceClient.On("ResolveRevision", mock.Anything, mock.Anything).Return(fakeResolveRevesionResponseHelm(), nil)
@@ -109,15 +122,15 @@ func fakeRepoServerClient(isHelm bool) *mocks.RepoServerServiceClient {
 }
 
 // return an ApplicationServiceServer which returns fake data
-func newTestAppServer(objects ...runtime.Object) *Server {
+func newTestAppServer(t *testing.T, objects ...runtime.Object) *Server {
 	f := func(enf *rbac.Enforcer) {
 		_ = enf.SetBuiltinPolicy(assets.BuiltinPolicyCSV)
 		enf.SetDefaultRole("role:admin")
 	}
-	return newTestAppServerWithEnforcerConfigure(f, objects...)
+	return newTestAppServerWithEnforcerConfigure(f, t, objects...)
 }
 
-func newTestAppServerWithEnforcerConfigure(f func(*rbac.Enforcer), objects ...runtime.Object) *Server {
+func newTestAppServerWithEnforcerConfigure(f func(*rbac.Enforcer), t *testing.T, objects ...runtime.Object) *Server {
 	kubeclientset := fake.NewSimpleClientset(&v1.ConfigMap{
 		ObjectMeta: metav1.ObjectMeta{
 			Namespace: testNamespace,
@@ -202,15 +215,83 @@ func newTestAppServerWithEnforcerConfigure(f func(*rbac.Enforcer), objects ...ru
 		panic("Timed out waiting for caches to sync")
 	}
 
+	broadcaster := new(appmocks.Broadcaster)
+	broadcaster.On("Subscribe", mock.Anything, mock.Anything).Return(func() {}).Run(func(args mock.Arguments) {
+		// Simulate the broadcaster notifying the subscriber of an application update.
+		// The second parameter to Subscribe is filters. For the purposes of tests, we ignore the filters. Future tests
+		// might require implementing those.
+		go func() {
+			events := args.Get(0).(chan *appsv1.ApplicationWatchEvent)
+			for _, obj := range objects {
+				app, ok := obj.(*appsv1.Application)
+				if ok {
+					oldVersion, err := strconv.Atoi(app.ResourceVersion)
+					if err != nil {
+						oldVersion = 0
+					}
+					clonedApp := app.DeepCopy()
+					clonedApp.ResourceVersion = fmt.Sprintf("%d", oldVersion+1)
+					events <- &appsv1.ApplicationWatchEvent{Type: watch.Added, Application: *clonedApp}
+				}
+			}
+		}()
+	})
+	broadcaster.On("OnAdd", mock.Anything).Return()
+	broadcaster.On("OnUpdate", mock.Anything, mock.Anything).Return()
+	broadcaster.On("OnDelete", mock.Anything).Return()
+
+	appStateCache := appstate.NewCache(cache.NewCache(cache.NewInMemoryCache(time.Hour)), time.Hour)
+	// pre-populate the app cache
+	for _, obj := range objects {
+		app, ok := obj.(*appsv1.Application)
+		if ok {
+			err := appStateCache.SetAppManagedResources(app.Name, []*appsv1.ResourceDiff{})
+			require.NoError(t, err)
+
+			// Pre-populate the resource tree based on the app's resources.
+			nodes := make([]appsv1.ResourceNode, len(app.Status.Resources))
+			for i, res := range app.Status.Resources {
+				nodes[i] = appsv1.ResourceNode{
+					ResourceRef: appsv1.ResourceRef{
+						Group:     res.Group,
+						Kind:      res.Kind,
+						Version:   res.Version,
+						Name:      res.Name,
+						Namespace: res.Namespace,
+						UID:       "fake",
+					},
+				}
+			}
+			err = appStateCache.SetAppResourcesTree(app.Name, &appsv1.ApplicationTree{
+				Nodes: nodes,
+			})
+			require.NoError(t, err)
+		}
+	}
+	appCache := servercache.NewCache(appStateCache, time.Hour, time.Hour, time.Hour)
+
+	kubectl := &kubetest.MockKubectlCmd{}
+	kubectl = kubectl.WithGetResourceFunc(func(_ context.Context, _ *rest.Config, gvk schema.GroupVersionKind, name string, namespace string) (*unstructured.Unstructured, error) {
+		for _, obj := range objects {
+			if obj.GetObjectKind().GroupVersionKind().GroupKind() == gvk.GroupKind() {
+				if obj, ok := obj.(*unstructured.Unstructured); ok && obj.GetName() == name && obj.GetNamespace() == namespace {
+					return obj, nil
+				}
+			}
+		}
+		return nil, nil
+	})
+
 	server, _ := NewServer(
 		testNamespace,
 		kubeclientset,
 		fakeAppsClientset,
 		factory.Argoproj().V1alpha1().Applications().Lister(),
 		appInformer,
+		broadcaster,
 		mockRepoClient,
-		nil,
-		&kubetest.MockKubectlCmd{},
+		appCache,
+		kubectl,
 		db,
 		enforcer,
 		sync.NewKeyLock(),
@@ -301,8 +382,428 @@ func createTestApp(testApp string, opts ...func(app *appsv1.Application)) *appsv
 	return &app
 }
 
+type TestServerStream struct {
+	ctx        context.Context
+	appName    string
+	headerSent bool
+}
+
+func (t *TestServerStream) SetHeader(metadata.MD) error {
+	return nil
+}
+
+func (t *TestServerStream) SendHeader(metadata.MD) error {
+	return nil
+}
+
+func (t *TestServerStream) SetTrailer(metadata.MD) {
+	return
+}
+
+func (t *TestServerStream) Context() context.Context {
+	return t.ctx
+}
+
+func (t *TestServerStream) SendMsg(m interface{}) error {
+	return nil
+}
+
+func (t *TestServerStream) RecvMsg(m interface{}) error {
+	return nil
+}
+
+func (t *TestServerStream) SendAndClose(r *apiclient.ManifestResponse) error {
+	return nil
+}
+
+func (t *TestServerStream) Recv() (*application.ApplicationManifestQueryWithFilesWrapper, error) {
+	if !t.headerSent {
+		t.headerSent = true
+		return &application.ApplicationManifestQueryWithFilesWrapper{Part: &application.ApplicationManifestQueryWithFilesWrapper_Query{
+			Query: &application.ApplicationManifestQueryWithFiles{
+				Name:     pointer.String(t.appName),
+				Checksum: pointer.String(""),
+			},
+		}}, nil
+	}
+	return nil, io.EOF
+}
+
+func (t *TestServerStream) ServerStream() TestServerStream {
+	return TestServerStream{}
+}
+
+type TestResourceTreeServer struct {
+	ctx context.Context
+}
+
+func (t *TestResourceTreeServer) Send(tree *appsv1.ApplicationTree) error {
+	return nil
+}
+
+func (t *TestResourceTreeServer) SetHeader(metadata.MD) error {
+	return nil
+}
+
+func (t *TestResourceTreeServer) SendHeader(metadata.MD) error {
+	return nil
+}
+
+func (t *TestResourceTreeServer) SetTrailer(metadata.MD) {
+	return
+}
+
+func (t *TestResourceTreeServer) Context() context.Context {
+	return t.ctx
+}
+
+func (t *TestResourceTreeServer) SendMsg(m interface{}) error {
+	return nil
+}
+
+func (t *TestResourceTreeServer) RecvMsg(m interface{}) error {
+	return nil
+}
+
+type TestPodLogsServer struct {
+	ctx context.Context
+}
+
+func (t *TestPodLogsServer) Send(log *application.LogEntry) error {
+	return nil
+}
+
+func (t *TestPodLogsServer) SetHeader(metadata.MD) error {
+	return nil
+}
+
+func (t *TestPodLogsServer) SendHeader(metadata.MD) error {
+	return nil
+}
+
+func (t *TestPodLogsServer) SetTrailer(metadata.MD) {
+	return
+}
+
+func (t *TestPodLogsServer) Context() context.Context {
+	return t.ctx
+}
+
+func (t *TestPodLogsServer) SendMsg(m interface{}) error {
+	return nil
+}
+
+func (t *TestPodLogsServer) RecvMsg(m interface{}) error {
+	return nil
+}
+
+func TestNoAppEnumeration(t *testing.T) {
+	// This test ensures that malicious users can't infer the existence or non-existence of Applications by inspecting
+	// error messages. The errors for "app does not exist" must be the same as errors for "you aren't allowed to
+	// interact with this app."
+
+	// These tests are only important on API calls where the full app RBAC name (project, namespace, and name) is _not_
+	// known based on the query parameters. For example, the Create call cannot leak existence of Applications, because
+	// the Application's project, namespace, and name are all specified in the API call. The call can be rejected
+	// immediately if the user does not have access. But the Delete endpoint may be called with just the Application
+	// name. So we cannot return a different error message for "does not exist" and "you don't have delete permissions,"
+	// because the user could infer that the Application exists if they do not get the "does not exist" message. For
+	// endpoints that do not require the full RBAC name, we must return a generic "permission denied" for both "does not
+	// exist" and "no access."
+
+	f := func(enf *rbac.Enforcer) {
+		_ = enf.SetBuiltinPolicy(assets.BuiltinPolicyCSV)
+		enf.SetDefaultRole("role:none")
+	}
+	deployment := k8sappsv1.Deployment{
+		TypeMeta: metav1.TypeMeta{
+			APIVersion: "apps/v1",
+			Kind:       "Deployment",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "test",
+		},
+	}
+	testApp := newTestApp(func(app *appsv1.Application) {
+		app.Name = "test"
+		app.Status.Resources = []appsv1.ResourceStatus{
+			{
+				Group:     deployment.GroupVersionKind().Group,
+				Kind:      deployment.GroupVersionKind().Kind,
+				Version:   deployment.GroupVersionKind().Version,
+				Name:      deployment.Name,
+				Namespace: deployment.Namespace,
+				Status:    "Synced",
+			},
+		}
+		app.Status.History = []appsv1.RevisionHistory{
+			{
+				ID: 0,
+				Source: appsv1.ApplicationSource{
+					TargetRevision: "something-old",
+				},
+			},
+		}
+	})
+	testDeployment := kube.MustToUnstructured(&deployment)
+	appServer := newTestAppServerWithEnforcerConfigure(f, t, testApp, testDeployment)
+
+	noRoleCtx := context.Background()
+	adminCtx := context.WithValue(noRoleCtx, "claims", &jwt.MapClaims{"groups": []string{"admin"}})
+
+	t.Run("Get", func(t *testing.T) {
+		_, err := appServer.Get(adminCtx, &application.ApplicationQuery{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.Get(noRoleCtx, &application.ApplicationQuery{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.Get(adminCtx, &application.ApplicationQuery{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("GetManifests", func(t *testing.T) {
+		_, err := appServer.GetManifests(adminCtx, &application.ApplicationManifestQuery{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.GetManifests(noRoleCtx, &application.ApplicationManifestQuery{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.GetManifests(adminCtx, &application.ApplicationManifestQuery{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("ListResourceEvents", func(t *testing.T) {
+		_, err := appServer.ListResourceEvents(adminCtx, &application.ApplicationResourceEventsQuery{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.ListResourceEvents(noRoleCtx, &application.ApplicationResourceEventsQuery{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ListResourceEvents(adminCtx, &application.ApplicationResourceEventsQuery{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("UpdateSpec", func(t *testing.T) {
+		_, err := appServer.UpdateSpec(adminCtx, &application.ApplicationUpdateSpecRequest{Name: pointer.String("test"), Spec: &appsv1.ApplicationSpec{
+			Destination: appsv1.ApplicationDestination{Namespace: "default", Server: "https://cluster-api.com"},
+			Source:      &appsv1.ApplicationSource{RepoURL: "https://some-fake-source", Path: "."},
+		}})
+		assert.NoError(t, err)
+		_, err = appServer.UpdateSpec(noRoleCtx, &application.ApplicationUpdateSpecRequest{Name: pointer.String("test"), Spec: &appsv1.ApplicationSpec{
+			Destination: appsv1.ApplicationDestination{Namespace: "default", Server: "https://cluster-api.com"},
+			Source:      &appsv1.ApplicationSource{RepoURL: "https://some-fake-source", Path: "."},
+		}})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.UpdateSpec(adminCtx, &application.ApplicationUpdateSpecRequest{Name: pointer.String("doest-not-exist"), Spec: &appsv1.ApplicationSpec{
+			Destination: appsv1.ApplicationDestination{Namespace: "default", Server: "https://cluster-api.com"},
+			Source:      &appsv1.ApplicationSource{RepoURL: "https://some-fake-source", Path: "."},
+		}})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("Patch", func(t *testing.T) {
+		_, err := appServer.Patch(adminCtx, &application.ApplicationPatchRequest{Name: pointer.String("test"), Patch: pointer.String(`[{"op": "replace", "path": "/spec/source/path", "value": "foo"}]`)})
+		assert.NoError(t, err)
+		_, err = appServer.Patch(noRoleCtx, &application.ApplicationPatchRequest{Name: pointer.String("test"), Patch: pointer.String(`[{"op": "replace", "path": "/spec/source/path", "value": "foo"}]`)})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.Patch(adminCtx, &application.ApplicationPatchRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("GetResource", func(t *testing.T) {
+		_, err := appServer.GetResource(adminCtx, &application.ApplicationResourceRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.GetResource(noRoleCtx, &application.ApplicationResourceRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.GetResource(adminCtx, &application.ApplicationResourceRequest{Name: pointer.String("doest-not-exist"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("PatchResource", func(t *testing.T) {
+		_, err := appServer.PatchResource(adminCtx, &application.ApplicationResourcePatchRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test"), Patch: pointer.String(`[{"op": "replace", "path": "/spec/replicas", "value": 3}]`)})
+		// This will always throw an error, because the kubectl mock for PatchResource is hard-coded to return nil.
+		// The best we can do is to confirm we get past the permission check.
+		assert.NotEqual(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.PatchResource(noRoleCtx, &application.ApplicationResourcePatchRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test"), Patch: pointer.String(`[{"op": "replace", "path": "/spec/replicas", "value": 3}]`)})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.PatchResource(adminCtx, &application.ApplicationResourcePatchRequest{Name: pointer.String("doest-not-exist"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test"), Patch: pointer.String(`[{"op": "replace", "path": "/spec/replicas", "value": 3}]`)})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("DeleteResource", func(t *testing.T) {
+		_, err := appServer.DeleteResource(adminCtx, &application.ApplicationResourceDeleteRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.DeleteResource(noRoleCtx, &application.ApplicationResourceDeleteRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.DeleteResource(adminCtx, &application.ApplicationResourceDeleteRequest{Name: pointer.String("doest-not-exist"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("ResourceTree", func(t *testing.T) {
+		_, err := appServer.ResourceTree(adminCtx, &application.ResourcesQuery{ApplicationName: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.ResourceTree(noRoleCtx, &application.ResourcesQuery{ApplicationName: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ResourceTree(adminCtx, &application.ResourcesQuery{ApplicationName: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("RevisionMetadata", func(t *testing.T) {
+		_, err := appServer.RevisionMetadata(adminCtx, &application.RevisionMetadataQuery{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.RevisionMetadata(noRoleCtx, &application.RevisionMetadataQuery{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.RevisionMetadata(adminCtx, &application.RevisionMetadataQuery{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("ManagedResources", func(t *testing.T) {
+		_, err := appServer.ManagedResources(adminCtx, &application.ResourcesQuery{ApplicationName: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.ManagedResources(noRoleCtx, &application.ResourcesQuery{ApplicationName: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ManagedResources(adminCtx, &application.ResourcesQuery{ApplicationName: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("Sync", func(t *testing.T) {
+		_, err := appServer.Sync(adminCtx, &application.ApplicationSyncRequest{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.Sync(noRoleCtx, &application.ApplicationSyncRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.Sync(adminCtx, &application.ApplicationSyncRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("TerminateOperation", func(t *testing.T) {
+		// The sync operation is already started from the previous test. We just need to set the field that the
+		// controller would set if this were an actual Argo CD environment.
+		setSyncRunningOperationState(t, appServer)
+		_, err := appServer.TerminateOperation(adminCtx, &application.OperationTerminateRequest{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.TerminateOperation(noRoleCtx, &application.OperationTerminateRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.TerminateOperation(adminCtx, &application.OperationTerminateRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("Rollback", func(t *testing.T) {
+		unsetSyncRunningOperationState(t, appServer)
+		_, err := appServer.Rollback(adminCtx, &application.ApplicationRollbackRequest{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.Rollback(noRoleCtx, &application.ApplicationRollbackRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.Rollback(adminCtx, &application.ApplicationRollbackRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("ListResourceActions", func(t *testing.T) {
+		_, err := appServer.ListResourceActions(adminCtx, &application.ApplicationResourceRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.ListResourceActions(noRoleCtx, &application.ApplicationResourceRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ListResourceActions(noRoleCtx, &application.ApplicationResourceRequest{Group: pointer.String("argoproj.io"), Kind: pointer.String("Application"), Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ListResourceActions(adminCtx, &application.ApplicationResourceRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("RunResourceAction", func(t *testing.T) {
+		_, err := appServer.RunResourceAction(adminCtx, &application.ResourceActionRunRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test"), Action: pointer.String("restart")})
+		assert.NoError(t, err)
+		_, err = appServer.RunResourceAction(noRoleCtx, &application.ResourceActionRunRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.RunResourceAction(noRoleCtx, &application.ResourceActionRunRequest{Group: pointer.String("argoproj.io"), Kind: pointer.String("Application"), Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.RunResourceAction(adminCtx, &application.ResourceActionRunRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("GetApplicationSyncWindows", func(t *testing.T) {
+		_, err := appServer.GetApplicationSyncWindows(adminCtx, &application.ApplicationSyncWindowsQuery{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.GetApplicationSyncWindows(noRoleCtx, &application.ApplicationSyncWindowsQuery{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.GetApplicationSyncWindows(adminCtx, &application.ApplicationSyncWindowsQuery{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("GetManifestsWithFiles", func(t *testing.T) {
+		err := appServer.GetManifestsWithFiles(&TestServerStream{ctx: adminCtx, appName: "test"})
+		assert.NoError(t, err)
+		err = appServer.GetManifestsWithFiles(&TestServerStream{ctx: noRoleCtx, appName: "test"})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		err = appServer.GetManifestsWithFiles(&TestServerStream{ctx: adminCtx, appName: "does-not-exist"})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("WatchResourceTree", func(t *testing.T) {
+		err := appServer.WatchResourceTree(&application.ResourcesQuery{ApplicationName: pointer.String("test")}, &TestResourceTreeServer{ctx: adminCtx})
+		assert.NoError(t, err)
+		err = appServer.WatchResourceTree(&application.ResourcesQuery{ApplicationName: pointer.String("test")}, &TestResourceTreeServer{ctx: noRoleCtx})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		err = appServer.WatchResourceTree(&application.ResourcesQuery{ApplicationName: pointer.String("does-not-exist")}, &TestResourceTreeServer{ctx: adminCtx})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("PodLogs", func(t *testing.T) {
+		err := appServer.PodLogs(&application.ApplicationPodLogsQuery{Name: pointer.String("test")}, &TestPodLogsServer{ctx: adminCtx})
+		assert.NoError(t, err)
+		err = appServer.PodLogs(&application.ApplicationPodLogsQuery{Name: pointer.String("test")}, &TestPodLogsServer{ctx: noRoleCtx})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		err = appServer.PodLogs(&application.ApplicationPodLogsQuery{Name: pointer.String("does-not-exist")}, &TestPodLogsServer{ctx: adminCtx})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("ListLinks", func(t *testing.T) {
+		_, err := appServer.ListLinks(adminCtx, &application.ListAppLinksRequest{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.ListLinks(noRoleCtx, &application.ListAppLinksRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ListLinks(adminCtx, &application.ListAppLinksRequest{Name: pointer.String("does-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	t.Run("ListResourceLinks", func(t *testing.T) {
+		_, err := appServer.ListResourceLinks(adminCtx, &application.ApplicationResourceRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.ListResourceLinks(noRoleCtx, &application.ApplicationResourceRequest{Name: pointer.String("test"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.ListResourceLinks(adminCtx, &application.ApplicationResourceRequest{Name: pointer.String("does-not-exist"), ResourceName: pointer.String("test"), Group: pointer.String("apps"), Kind: pointer.String("Deployment"), Namespace: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+
+	// Do this last so other stuff doesn't fail.
+	t.Run("Delete", func(t *testing.T) {
+		_, err := appServer.Delete(adminCtx, &application.ApplicationDeleteRequest{Name: pointer.String("test")})
+		assert.NoError(t, err)
+		_, err = appServer.Delete(noRoleCtx, &application.ApplicationDeleteRequest{Name: pointer.String("test")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+		_, err = appServer.Delete(adminCtx, &application.ApplicationDeleteRequest{Name: pointer.String("doest-not-exist")})
+		assert.Equal(t, permissionDeniedErr.Error(), err.Error(), "error message must be _only_ the permission error, to avoid leaking information about app existence")
+	})
+}
+
+// setSyncRunningOperationState simulates starting a sync operation on the given app.
+func setSyncRunningOperationState(t *testing.T, appServer *Server) {
+	appIf := appServer.appclientset.ArgoprojV1alpha1().Applications("default")
+	app, err := appIf.Get(context.Background(), "test", metav1.GetOptions{})
+	require.NoError(t, err)
+	// This sets the status that would be set by the controller usually.
+	app.Status.OperationState = &appsv1.OperationState{Phase: synccommon.OperationRunning, Operation: appsv1.Operation{Sync: &appsv1.SyncOperation{}}}
+	_, err = appIf.Update(context.Background(), app, metav1.UpdateOptions{})
+	require.NoError(t, err)
+}
+
+// unsetSyncRunningOperationState simulates finishing a sync operation on the given app.
+func unsetSyncRunningOperationState(t *testing.T, appServer *Server) {
+	appIf := appServer.appclientset.ArgoprojV1alpha1().Applications("default")
+	app, err := appIf.Get(context.Background(), "test", metav1.GetOptions{})
+	require.NoError(t, err)
+	app.Operation = nil
+	app.Status.OperationState = nil
+	_, err = appIf.Update(context.Background(), app, metav1.UpdateOptions{})
+	require.NoError(t, err)
+}
+
 func TestListAppsInNamespaceWithLabels(t *testing.T) {
-	appServer := newTestAppServer(newTestApp(func(app *appsv1.Application) {
+	appServer := newTestAppServer(t, newTestApp(func(app *appsv1.Application) {
 		app.Name = "App1"
 		app.ObjectMeta.Namespace = "test-namespace"
 		app.SetLabels(map[string]string{"key1": "value1", "key2": "value1"})
@@ -323,7 +824,7 @@ func TestListAppsInNamespaceWithLabels(t *testing.T) {
 }
 
 func TestListAppsInDefaultNSWithLabels(t *testing.T) {
-	appServer := newTestAppServer(newTestApp(func(app *appsv1.Application) {
+	appServer := newTestAppServer(t, newTestApp(func(app *appsv1.Application) {
 		app.Name = "App1"
 		app.SetLabels(map[string]string{"key1": "value1", "key2": "value1"})
 	}), newTestApp(func(app *appsv1.Application) {
@@ -402,7 +903,7 @@ func testListAppsWithLabels(t *testing.T, appQuery application.ApplicationQuery,
 }
 
 func TestListAppWithProjects(t *testing.T) {
-	appServer := newTestAppServer(newTestApp(func(app *appsv1.Application) {
+	appServer := newTestAppServer(t, newTestApp(func(app *appsv1.Application) {
 		app.Name = "App1"
 		app.Spec.Project = "test-project1"
 	}), newTestApp(func(app *appsv1.Application) {
@@ -453,7 +954,7 @@ func TestListAppWithProjects(t *testing.T) {
 }
 
 func TestListApps(t *testing.T) {
-	appServer := newTestAppServer(newTestApp(func(app *appsv1.Application) {
+	appServer := newTestAppServer(t, newTestApp(func(app *appsv1.Application) {
 		app.Name = "bcd"
 	}), newTestApp(func(app *appsv1.Application) {
 		app.Name = "abc"
@@ -501,7 +1002,7 @@ g, group-49, role:test3
 `
 		_ = enf.SetUserPolicy(policy)
 	}
-	appServer := newTestAppServerWithEnforcerConfigure(f, objects...)
+	appServer := newTestAppServerWithEnforcerConfigure(f, t, objects...)
 
 	res, err := appServer.List(ctx, &application.ApplicationQuery{})
 
@@ -515,7 +1016,7 @@ g, group-49, role:test3
 
 func TestCreateApp(t *testing.T) {
 	testApp := newTestApp()
-	appServer := newTestAppServer()
+	appServer := newTestAppServer(t)
 	testApp.Spec.Project = ""
 	createReq := application.ApplicationCreateRequest{
 		Application: testApp,
@@ -528,7 +1029,7 @@ func TestCreateApp(t *testing.T) {
 }
 
 func TestCreateAppWithDestName(t *testing.T) {
-	appServer := newTestAppServer()
+	appServer := newTestAppServer(t)
 	testApp := newTestAppWithDestName()
 	createReq := application.ApplicationCreateRequest{
 		Application: testApp,
@@ -541,7 +1042,7 @@ func TestCreateAppWithDestName(t *testing.T) {
 
 func TestUpdateApp(t *testing.T) {
 	testApp := newTestApp()
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 	testApp.Spec.Project = ""
 	app, err := appServer.Update(context.Background(), &application.ApplicationUpdateRequest{
 		Application: testApp,
@@ -552,7 +1053,7 @@ func TestUpdateApp(t *testing.T) {
 
 func TestUpdateAppSpec(t *testing.T) {
 	testApp := newTestApp()
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 	testApp.Spec.Project = ""
 	spec, err := appServer.UpdateSpec(context.Background(), &application.ApplicationUpdateSpecRequest{
 		Name: &testApp.Name,
@@ -567,7 +1068,7 @@ func TestUpdateAppSpec(t *testing.T) {
 
 func TestDeleteApp(t *testing.T) {
 	ctx := context.Background()
-	appServer := newTestAppServer()
+	appServer := newTestAppServer(t)
 	createReq := application.ApplicationCreateRequest{
 		Application: newTestApp(),
 	}
@@ -655,20 +1156,9 @@ func TestDeleteApp(t *testing.T) {
 	})
 }
 
-func TestDeleteApp_InvalidName(t *testing.T) {
-	appServer := newTestAppServer()
-	_, err := appServer.Delete(context.Background(), &application.ApplicationDeleteRequest{
-		Name: pointer.StringPtr("foo"),
-	})
-	if !assert.Error(t, err) {
-		return
-	}
-	assert.True(t, apierrors.IsNotFound(err))
-}
-
 func TestSyncAndTerminate(t *testing.T) {
 	ctx := context.Background()
-	appServer := newTestAppServer()
+	appServer := newTestAppServer(t)
 	testApp := newTestApp()
 	testApp.Spec.Source.RepoURL = "https://github.com/argoproj/argo-cd.git"
 	createReq := application.ApplicationCreateRequest{
@@ -708,7 +1198,7 @@ func TestSyncAndTerminate(t *testing.T) {
 
 func TestSyncHelm(t *testing.T) {
 	ctx := context.Background()
-	appServer := newTestAppServer()
+	appServer := newTestAppServer(t)
 	testApp := newTestApp()
 	testApp.Spec.Source.RepoURL = "https://argoproj.github.io/argo-helm"
 	testApp.Spec.Source.Path = ""
@@ -732,7 +1222,7 @@ func TestSyncHelm(t *testing.T) {
 
 func TestSyncGit(t *testing.T) {
 	ctx := context.Background()
-	appServer := newTestAppServer()
+	appServer := newTestAppServer(t)
 	testApp := newTestApp()
 	testApp.Spec.Source.RepoURL = "https://github.com/org/test"
 	testApp.Spec.Source.Path = "deploy"
@@ -765,7 +1255,7 @@ func TestRollbackApp(t *testing.T) {
 		Revision: "abc",
 		Source:   *testApp.Spec.Source.DeepCopy(),
 	}}
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 
 	updatedApp, err := appServer.Rollback(context.Background(), &application.ApplicationRollbackRequest{
 		Name: &testApp.Name,
@@ -785,64 +1275,71 @@ func TestUpdateAppProject(t *testing.T) {
 	ctx := context.Background()
 	// nolint:staticcheck
 	ctx = context.WithValue(ctx, "claims", &jwt.StandardClaims{Subject: "admin"})
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 	appServer.enf.SetDefaultRole("")
 
-	// Verify normal update works (without changing project)
-	_ = appServer.enf.SetBuiltinPolicy(`p, admin, applications, update, default/test-app, allow`)
-	_, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
-	assert.NoError(t, err)
+	t.Run("update without changing project", func(t *testing.T) {
+		_ = appServer.enf.SetBuiltinPolicy(`p, admin, applications, update, default/test-app, allow`)
+		_, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
+		assert.NoError(t, err)
+	})
 
-	// Verify caller cannot update to another project
-	testApp.Spec.Project = "my-proj"
-	_, err = appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
-	assert.Equal(t, status.Code(err), codes.PermissionDenied)
+	t.Run("cannot update to another project", func(t *testing.T) {
+		testApp.Spec.Project = "my-proj"
+		_, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
+		assert.Equal(t, status.Code(err), codes.PermissionDenied)
+	})
 
-	// Verify inability to change projects without create privileges in new project
-	_ = appServer.enf.SetBuiltinPolicy(`
+	t.Run("cannot change projects without create privileges", func(t *testing.T) {
+		_ = appServer.enf.SetBuiltinPolicy(`
 p, admin, applications, update, default/test-app, allow
 p, admin, applications, update, my-proj/test-app, allow
 `)
-	_, err = appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
-	statusErr := grpc.UnwrapGRPCStatus(err)
-	assert.NotNil(t, statusErr)
-	assert.Equal(t, codes.PermissionDenied, statusErr.Code())
+		_, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
+		statusErr := grpc.UnwrapGRPCStatus(err)
+		assert.NotNil(t, statusErr)
+		assert.Equal(t, codes.PermissionDenied, statusErr.Code())
+	})
 
-	// Verify inability to change projects without update privileges in new project
-	_ = appServer.enf.SetBuiltinPolicy(`
+	t.Run("cannot change projects without update privileges in new project", func(t *testing.T) {
+		_ = appServer.enf.SetBuiltinPolicy(`
 p, admin, applications, update, default/test-app, allow
 p, admin, applications, create, my-proj/test-app, allow
 `)
-	_, err = appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
-	assert.Equal(t, status.Code(err), codes.PermissionDenied)
+		_, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
+		assert.Equal(t, status.Code(err), codes.PermissionDenied)
+	})
 
-	// Verify inability to change projects without update privileges in old project
-	_ = appServer.enf.SetBuiltinPolicy(`
+	t.Run("cannot change projects without update privileges in old project", func(t *testing.T) {
+		_ = appServer.enf.SetBuiltinPolicy(`
 p, admin, applications, create, my-proj/test-app, allow
 p, admin, applications, update, my-proj/test-app, allow
 `)
-	_, err = appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
-	statusErr = grpc.UnwrapGRPCStatus(err)
-	assert.NotNil(t, statusErr)
-	assert.Equal(t, codes.PermissionDenied, statusErr.Code())
+		_, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
+		statusErr := grpc.UnwrapGRPCStatus(err)
+		assert.NotNil(t, statusErr)
+		assert.Equal(t, codes.PermissionDenied, statusErr.Code())
+	})
 
-	// Verify can update project with proper permissions
-	_ = appServer.enf.SetBuiltinPolicy(`
+	t.Run("can update project with proper permissions", func(t *testing.T) {
+		// Verify can update project with proper permissions
+		_ = appServer.enf.SetBuiltinPolicy(`
 p, admin, applications, update, default/test-app, allow
 p, admin, applications, create, my-proj/test-app, allow
 p, admin, applications, update, my-proj/test-app, allow
 `)
-	updatedApp, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
-	assert.NoError(t, err)
-	assert.Equal(t, "my-proj", updatedApp.Spec.Project)
+		updatedApp, err := appServer.Update(ctx, &application.ApplicationUpdateRequest{Application: testApp})
+		assert.NoError(t, err)
+		assert.Equal(t, "my-proj", updatedApp.Spec.Project)
+	})
 }
 
 func TestAppJsonPatch(t *testing.T) {
 	testApp := newTestAppWithAnnotations()
 	ctx := context.Background()
 	// nolint:staticcheck
 	ctx = context.WithValue(ctx, "claims", &jwt.StandardClaims{Subject: "admin"})
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 	appServer.enf.SetDefaultRole("")
 
 	app, err := appServer.Patch(ctx, &application.ApplicationPatchRequest{Name: &testApp.Name, Patch: pointer.String("garbage")})
@@ -867,7 +1364,7 @@ func TestAppMergePatch(t *testing.T) {
 	ctx := context.Background()
 	// nolint:staticcheck
 	ctx = context.WithValue(ctx, "claims", &jwt.StandardClaims{Subject: "admin"})
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 	appServer.enf.SetDefaultRole("")
 
 	app, err := appServer.Patch(ctx, &application.ApplicationPatchRequest{
@@ -880,7 +1377,7 @@ func TestServer_GetApplicationSyncWindowsState(t *testing.T) {
 	t.Run("Active", func(t *testing.T) {
 		testApp := newTestApp()
 		testApp.Spec.Project = "proj-maint"
-		appServer := newTestAppServer(testApp)
+		appServer := newTestAppServer(t, testApp)
 
 		active, err := appServer.GetApplicationSyncWindows(context.Background(), &application.ApplicationSyncWindowsQuery{Name: &testApp.Name})
 		assert.NoError(t, err)
@@ -889,7 +1386,7 @@ func TestServer_GetApplicationSyncWindowsState(t *testing.T) {
 	t.Run("Inactive", func(t *testing.T) {
 		testApp := newTestApp()
 		testApp.Spec.Project = "default"
-		appServer := newTestAppServer(testApp)
+		appServer := newTestAppServer(t, testApp)
 
 		active, err := appServer.GetApplicationSyncWindows(context.Background(), &application.ApplicationSyncWindowsQuery{Name: &testApp.Name})
 		assert.NoError(t, err)
@@ -898,7 +1395,7 @@ func TestServer_GetApplicationSyncWindowsState(t *testing.T) {
 	t.Run("ProjectDoesNotExist", func(t *testing.T) {
 		testApp := newTestApp()
 		testApp.Spec.Project = "none"
-		appServer := newTestAppServer(testApp)
+		appServer := newTestAppServer(t, testApp)
 
 		active, err := appServer.GetApplicationSyncWindows(context.Background(), &application.ApplicationSyncWindowsQuery{Name: &testApp.Name})
 		assert.Contains(t, err.Error(), "not found")
@@ -916,7 +1413,7 @@ func TestGetCachedAppState(t *testing.T) {
 			Namespace: testNamespace,
 		},
 	}
-	appServer := newTestAppServer(testApp, testProj)
+	appServer := newTestAppServer(t, testApp, testProj)
 	fakeClientSet := appServer.appclientset.(*apps.Clientset)
 	fakeClientSet.AddReactor("get", "applications", func(action kubetesting.Action) (handled bool, ret runtime.Object, err error) {
 		return true, &appsv1.Application{Spec: appsv1.ApplicationSpec{Source: &appsv1.ApplicationSource{}}}, nil
@@ -1095,7 +1592,7 @@ func TestGetAppRefresh_NormalRefresh(t *testing.T) {
 	defer cancel()
 	testApp := newTestApp()
 	testApp.ObjectMeta.ResourceVersion = "1"
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 
 	var patched int32
 
@@ -1123,7 +1620,7 @@ func TestGetAppRefresh_HardRefresh(t *testing.T) {
 	defer cancel()
 	testApp := newTestApp()
 	testApp.ObjectMeta.ResourceVersion = "1"
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 
 	var getAppDetailsQuery *apiclient.RepoServerAppDetailsQuery
 	mockRepoServiceClient := mocks.RepoServerServiceClient{}
@@ -1173,7 +1670,7 @@ func TestInferResourcesStatusHealth(t *testing.T) {
 		Name:      "guestbook-stateful",
 		Namespace: "default",
 	}}
-	appServer := newTestAppServer(testApp)
+	appServer := newTestAppServer(t, testApp)
 	appStateCache := appstate.NewCache(cacheClient, time.Minute)
 	err := appStateCache.SetAppResourcesTree(testApp.Name, &appsv1.ApplicationTree{Nodes: []appsv1.ResourceNode{{
 		ResourceRef: appsv1.ResourceRef{

@@ -23,6 +23,14 @@ func (s *subscriber) matches(event *appv1.ApplicationWatchEvent) bool {
 	return true
 }
 
+// Broadcaster is an interface for broadcasting application informer watch events to multiple subscribers.
+type Broadcaster interface {
+	Subscribe(ch chan *appv1.ApplicationWatchEvent, filters ...func(event *appv1.ApplicationWatchEvent) bool) func()
+	OnAdd(interface{})
+	OnUpdate(interface{}, interface{})
+	OnDelete(interface{})
+}
+
 type broadcasterHandler struct {
 	lock        sync.Mutex
 	subscribers []*subscriber

@@ -0,0 +1,66 @@
+// Code generated by mockery v2.13.1. DO NOT EDIT.
+
+package mocks
+
+import (
+	v1alpha1 "github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
+	mock "github.com/stretchr/testify/mock"
+)
+
+// Broadcaster is an autogenerated mock type for the Broadcaster type
+type Broadcaster struct {
+	mock.Mock
+}
+
+// OnAdd provides a mock function with given fields: _a0
+func (_m *Broadcaster) OnAdd(_a0 interface{}) {
+	_m.Called(_a0)
+}
+
+// OnDelete provides a mock function with given fields: _a0
+func (_m *Broadcaster) OnDelete(_a0 interface{}) {
+	_m.Called(_a0)
+}
+
+// OnUpdate provides a mock function with given fields: _a0, _a1
+func (_m *Broadcaster) OnUpdate(_a0 interface{}, _a1 interface{}) {
+	_m.Called(_a0, _a1)
+}
+
+// Subscribe provides a mock function with given fields: ch, filters
+func (_m *Broadcaster) Subscribe(ch chan *v1alpha1.ApplicationWatchEvent, filters ...func(*v1alpha1.ApplicationWatchEvent) bool) func() {
+	_va := make([]interface{}, len(filters))
+	for _i := range filters {
+		_va[_i] = filters[_i]
+	}
+	var _ca []interface{}
+	_ca = append(_ca, ch)
+	_ca = append(_ca, _va...)
+	ret := _m.Called(_ca...)
+
+	var r0 func()
+	if rf, ok := ret.Get(0).(func(chan *v1alpha1.ApplicationWatchEvent, ...func(*v1alpha1.ApplicationWatchEvent) bool) func()); ok {
+		r0 = rf(ch, filters...)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(func())
+		}
+	}
+
+	return r0
+}
+
+type mockConstructorTestingTNewBroadcaster interface {
+	mock.TestingT
+	Cleanup(func())
+}
+
+// NewBroadcaster creates a new instance of Broadcaster. It also registers a testing interface on the mock and a cleanup function to assert the mocks expectations.
+func NewBroadcaster(t mockConstructorTestingTNewBroadcaster) *Broadcaster {
+	mock := &Broadcaster{}
+	mock.Mock.Test(t)
+
+	t.Cleanup(func() { mock.AssertExpectations(t) })
+
+	return mock
+}

@@ -768,6 +768,7 @@ func newArgoCDServiceSet(a *ArgoCDServer) *ArgoCDServiceSet {
 		a.AppClientset,
 		a.appLister,
 		a.appInformer,
+		nil,
 		a.RepoClientset,
 		a.Cache,
 		kubectl,

@@ -429,7 +429,9 @@ func TestNamespacedInvalidAppProject(t *testing.T) {
 		IgnoreErrors().
 		CreateApp().
 		Then().
-		Expect(Error("", "application references project does-not-exist which does not exist"))
+		// We're not allowed to infer whether the project exists based on this error message. Instead, we get a generic
+		// permission denied error.
+		Expect(Error("", "permission denied"))
 }
 
 func TestNamespacedAppDeletion(t *testing.T) {

@@ -413,7 +413,9 @@ func TestInvalidAppProject(t *testing.T) {
 		IgnoreErrors().
 		CreateApp().
 		Then().
-		Expect(Error("", "application references project does-not-exist which does not exist"))
+		// We're not allowed to infer whether the project exists based on this error message. Instead, we get a generic
+		// permission denied error.
+		Expect(Error("", "permission denied"))
 }
 
 func TestAppDeletion(t *testing.T) {