feat: remove enableSessionKeepAlive flag

src/setupTests.ts

@@ -92,7 +92,6 @@ vi.mock('shared/hooks/useFeatureFlags', () => ({
       enableMfa: false,
       enableAdminAnnouncementBanner: false,
       enableAuditLogs: true,
-      enableSessionKeepAlive: false,
     },
     resetLDContext: vi.fn(),
   })),

src/shared/hooks/useFeatureFlags.const.ts

@@ -23,7 +23,6 @@ export const FeatureFlagDefaults: FeatureFlags = {
   enableMfa: true,
   enableAdminAnnouncementBanner: false,
   enableAuditLogs: false,
-  enableSessionKeepAlive: false,
 };
 
 export const PROHIBITED_PII_KEYS = ['firstName', 'lastName', 'email'];

src/shared/hooks/useSessionKeepAlive/useSessionAdoption.test.ts

@@ -1,7 +1,6 @@
 import { act } from '@testing-library/react';
 
 import { authStorage } from 'shared/utils';
-import { useFeatureFlags } from 'shared/hooks/useFeatureFlags';
 import { renderHookWithProviders } from 'shared/utils/renderHookWithProviders';
 import { getPreloadedState } from 'shared/tests/getPreloadedState';
 import {
@@ -30,12 +29,6 @@ const ANNOUNCED = {
 
 const mockedReload = vi.fn();
 
-const setFlag = (enableSessionKeepAlive: boolean) =>
-  vi.mocked(useFeatureFlags).mockReturnValue({
-    featureFlags: { enableSessionKeepAlive },
-    resetLDContext: vi.fn(),
-  } as never);
-
 // Mirrors how the routes consume this: the hook re-renders, and the token is read afterwards.
 const renderAdoption = () =>
   renderHookWithProviders(
@@ -63,7 +56,6 @@ describe('useSessionAdoption', () => {
     sessionStorage.clear();
     vi.stubGlobal('BroadcastChannel', InMemoryBroadcastChannel);
     vi.stubGlobal('location', { ...window.location, reload: mockedReload });
-    setFlag(true);
 
     sibling = new InMemoryBroadcastChannel(SESSION_CHANNEL_NAME);
   });
@@ -118,15 +110,6 @@ describe('useSessionAdoption', () => {
     expect(authStorage.getRefreshToken()).toBe(ANNOUNCED.refreshToken);
   });
 
-  test('ignores announcements when the flag is off', () => {
-    setFlag(false);
-    renderAdoption();
-
-    announceSession(sibling);
-
-    expect(authStorage.getRefreshToken()).toBeNull();
-  });
-
   test('asks for a session when the tab comes back into focus', () => {
     const onSiblingMessage = vi.fn();
     sibling.onmessage = onSiblingMessage;

src/shared/hooks/useSessionKeepAlive/useSessionAdoption.ts

@@ -2,7 +2,6 @@ import { useEffect, useReducer } from 'react';
 
 import { authStorage } from 'shared/utils/authStorage';
 import { SessionStorageKeys } from 'shared/utils/storage';
-import { useFeatureFlags } from 'shared/hooks/useFeatureFlags';
 
 import { getLastActivityAt } from './sessionStore';
 import { publishSessionMessage, subscribeSessionSync } from './sessionSync';
@@ -14,12 +13,11 @@ import { resolveSessionConfig } from './useSessionKeepAlive.utils';
 // So it listens for a session being announced, and asks again whenever it returns to focus, for
 // the case where the browser had frozen it when the announcement went out.
 export const useSessionAdoption = () => {
-  const { featureFlags } = useFeatureFlags();
   // Adopting writes to storage, which no component is watching. This re-renders so the routes
   // read the token that just arrived.
   const [, onAdopted] = useReducer((count: number) => count + 1, 0);
 
-  const isListening = !!featureFlags.enableSessionKeepAlive && !authStorage.getRefreshToken();
+  const isListening = !authStorage.getRefreshToken();
 
   useEffect(() => {
     if (!isListening) {

src/shared/hooks/useSessionKeepAlive/useSessionKeepAlive.test.ts

@@ -3,7 +3,6 @@ import { act } from '@testing-library/react';
 import { refreshTokens } from 'shared/api';
 import { authStorage } from 'shared/utils';
 import { PlainStorageKeys } from 'shared/utils/storage';
-import { useFeatureFlags } from 'shared/hooks/useFeatureFlags';
 import { useLogout } from 'shared/hooks/useLogout';
 import { renderHookWithProviders } from 'shared/utils/renderHookWithProviders';
 import { getPreloadedState } from 'shared/tests/getPreloadedState';
@@ -15,7 +14,7 @@ import { state as authState } from 'modules/Auth/state/Auth.state';
 
 import { clearSessionState, setLastActivityAt } from './sessionStore';
 import { useSessionKeepAlive } from './useSessionKeepAlive';
-import { closeSessionSync, publishSessionMessage } from './sessionSync';
+import { closeSessionSync } from './sessionSync';
 import { SESSION_CHANNEL_NAME, SESSION_REQUEST_WINDOW_MS } from './sessionSync.const';
 import { SessionMessage, SessionState } from './sessionSync.types';
 import { MS_IN_MIN, MS_IN_SEC } from './useSessionKeepAlive.const';
@@ -42,12 +41,6 @@ const tokenExpiringIn = (ms: number) =>
 const refreshTokenFor = (sessionId: string) =>
   `header.${btoa(JSON.stringify({ family: sessionId }))}.signature`;
 
-const setFlag = (enableSessionKeepAlive: boolean) =>
-  vi.mocked(useFeatureFlags).mockReturnValue({
-    featureFlags: { enableSessionKeepAlive },
-    resetLDContext: vi.fn(),
-  } as never);
-
 // A sibling tab that replies to every session request with the state it is given.
 const answerSessionRequests = (state: Partial<SessionState>) => {
   const sibling = new InMemoryBroadcastChannel(SESSION_CHANNEL_NAME);
@@ -66,9 +59,9 @@ const answerSessionRequests = (state: Partial<SessionState>) => {
   };
 };
 
-const renderEngine = () =>
+const renderEngine = (isAuthorized = true) =>
   renderHookWithProviders(useSessionKeepAlive, {
-    preloadedState: { ...getPreloadedState(), auth: { ...authState, isAuthorized: true } },
+    preloadedState: { ...getPreloadedState(), auth: { ...authState, isAuthorized } },
   });
 
 describe('useSessionKeepAlive', () => {
@@ -82,7 +75,6 @@ describe('useSessionKeepAlive', () => {
 
     vi.mocked(useLogout).mockReturnValue(mockedLogout);
     mockedRefreshTokens.mockResolvedValue({ accessToken: 'a', refreshToken: 'r' });
-    setFlag(true);
     authStorage.setAccessToken(tokenExpiringIn(TOKEN_LIFETIME_MS));
     authStorage.setRefreshToken(refreshTokenFor(SESSION_ID));
   });
@@ -463,9 +455,8 @@ describe('useSessionKeepAlive', () => {
     });
   });
 
-  test('neither refreshes nor logs out nor syncs when the flag is off', () => {
-    setFlag(false);
-    renderEngine();
+  test('neither refreshes nor logs out nor syncs until the session is authorized', () => {
+    renderEngine(false);
     const sibling = new InMemoryBroadcastChannel(SESSION_CHANNEL_NAME);
     const onSiblingMessage = vi.fn();
     sibling.onmessage = onSiblingMessage;
@@ -474,7 +465,6 @@ describe('useSessionKeepAlive', () => {
     act(() => {
       vi.advanceTimersByTime(IDLE_TIMEOUT_MS * 2);
       window.dispatchEvent(new Event('keydown'));
-      publishSessionMessage({ type: 'SESSION_REQUEST' });
       sibling.postMessage({
         type: 'TOKENS_UPDATED',
         payload: {
@@ -492,8 +482,7 @@ describe('useSessionKeepAlive', () => {
     expect(authStorage.getAccessToken()).toBe(mine);
   });
 
-  test('still records activity when the flag is off, so the boot check has a clock to read', () => {
-    setFlag(false);
+  test('records activity as soon as the session is live, so the boot check has a clock to read', () => {
     renderEngine();
 
     expect(localStorage.getItem(PlainStorageKeys.LastActivityAt)).toBe(String(Date.now()));

src/shared/hooks/useSessionKeepAlive/useSessionKeepAlive.ts

@@ -3,7 +3,6 @@ import { useEffect, useRef } from 'react';
 import { auth } from 'redux/modules';
 import { refreshTokens } from 'shared/api';
 import { authStorage, getTokenExpiration } from 'shared/utils';
-import { useFeatureFlags } from 'shared/hooks/useFeatureFlags';
 import { useLogout } from 'shared/hooks/useLogout';
 
 import { startActivityTracking, stopActivityTracking } from './activityTracker';
@@ -15,20 +14,17 @@ import { getSessionId } from './sessionSync.utils';
 import { resolveSessionConfig } from './useSessionKeepAlive.utils';
 
 export const useSessionKeepAlive = () => {
-  const { featureFlags } = useFeatureFlags();
   const isAuthorized = auth.useAuthorized();
   const logout = useLogout();
 
   // Refreshed every render so the logout never closes over a stale email or workspace.
   const logoutRef = useRef(logout);
   logoutRef.current = logout;
 
-  const isEnabled = !!featureFlags.enableSessionKeepAlive && isAuthorized;
   // Set by the engine below, so tracking can re-arm the timers without owning them.
   const scheduleRef = useRef<(() => void) | null>(null);
 
-  // Runs with the flag off too: a session outlives its tab now, and the boot check reads this
-  // clock to decide whether one left behind may carry on.
+  // Kept apart from the engine: the boot check reads this clock, so it outlives any teardown.
   useEffect(() => {
     if (!isAuthorized) return;
 
@@ -38,7 +34,7 @@ export const useSessionKeepAlive = () => {
   }, [isAuthorized]);
 
   useEffect(() => {
-    if (!isEnabled) return;
+    if (!isAuthorized) return;
 
     const { idleTimeoutMs, refreshLeadMs } = resolveSessionConfig();
     let refreshTimer: ReturnType<typeof setTimeout>;
@@ -169,5 +165,5 @@ export const useSessionKeepAlive = () => {
       document.removeEventListener('visibilitychange', handleVisibilityChange);
       unsubscribe();
     };
-  }, [isEnabled]);
+  }, [isAuthorized]);
 };

src/shared/types/featureFlags.ts

@@ -26,5 +26,4 @@ export type FeatureFlags = Partial<{
   enableMfa: boolean;
   enableAdminAnnouncementBanner: boolean;
   enableAuditLogs: boolean;
-  enableSessionKeepAlive: boolean;
 }>;