Auth cookie persistence (#8839)

Adding `Persistence.COOKIE` a new persistence method backed by cookies. The `browserCookiePersistence` implementation is designed to be used in conjunction with middleware that ensures both your front and backend authentication state remains synchronized.

.changeset/orange-turtles-taste.md

@@ -0,0 +1,8 @@
+---
+'firebase': minor
+'@firebase/auth': minor
+---
+
+Adding `Persistence.COOKIE` a new persistence method backed by cookies. The
+`browserCookiePersistence` implementation is designed to be used in conjunction with middleware that
+ensures both your front and backend authentication state remains synchronized.

common/api-review/auth.api.md

@@ -258,6 +258,9 @@ export interface AuthSettings {
 // @public
 export function beforeAuthStateChanged(auth: Auth, callback: (user: User | null) => void | Promise<void>, onAbort?: () => void): Unsubscribe;
 
+// @beta
+export const browserCookiePersistence: Persistence;
+
 // @public
 export const browserLocalPersistence: Persistence;
 
@@ -596,7 +599,7 @@ export interface PasswordValidationStatus {
 
 // @public
 export interface Persistence {
-    readonly type: 'SESSION' | 'LOCAL' | 'NONE';
+    readonly type: 'SESSION' | 'LOCAL' | 'NONE' | 'COOKIE';
 }
 
 // @public

docs-devsite/auth.md

@@ -150,6 +150,7 @@ Firebase Authentication
 |  --- | --- |
 |  [ActionCodeOperation](./auth.md#actioncodeoperation) | An enumeration of the possible email action types. |
 |  [AuthErrorCodes](./auth.md#autherrorcodes) | A map of potential <code>Auth</code> error codes, for easier comparison with errors thrown by the SDK. |
+|  [browserCookiePersistence](./auth.md#browsercookiepersistence) | <b><i>(Public Preview)</i></b> An implementation of [Persistence](./auth.persistence.md#persistence_interface) of type <code>COOKIE</code>, for use on the client side in applications leveraging hybrid rendering and middleware. |
 |  [browserLocalPersistence](./auth.md#browserlocalpersistence) | An implementation of [Persistence](./auth.persistence.md#persistence_interface) of type <code>LOCAL</code> using <code>localStorage</code> for the underlying storage. |
 |  [browserPopupRedirectResolver](./auth.md#browserpopupredirectresolver) | An implementation of [PopupRedirectResolver](./auth.popupredirectresolver.md#popupredirectresolver_interface) suitable for browser based applications. |
 |  [browserSessionPersistence](./auth.md#browsersessionpersistence) | An implementation of [Persistence](./auth.persistence.md#persistence_interface) of <code>SESSION</code> using <code>sessionStorage</code> for the underlying storage. |
@@ -1960,6 +1961,21 @@ AUTH_ERROR_CODES_MAP_DO_NOT_USE_INTERNALLY: {
 }
 ```
 
+## browserCookiePersistence
+
+> This API is provided as a preview for developers and may change based on feedback that we receive. Do not use this API in a production environment.
+> 
+
+An implementation of [Persistence](./auth.persistence.md#persistence_interface) of type `COOKIE`<!-- -->, for use on the client side in applications leveraging hybrid rendering and middleware.
+
+This persistence method requires companion middleware to function, such as that provided by [ReactFire](https://firebaseopensource.com/projects/firebaseextended/reactfire/) for NextJS.
+
+<b>Signature:</b>
+
+```typescript
+browserCookiePersistence: Persistence
+```
+
 ## browserLocalPersistence
 
 An implementation of [Persistence](./auth.persistence.md#persistence_interface) of type `LOCAL` using `localStorage` for the underlying storage.

docs-devsite/auth.persistence.md

@@ -22,14 +22,14 @@ export interface Persistence
 
 |  Property | Type | Description |
 |  --- | --- | --- |
-|  [type](./auth.persistence.md#persistencetype) | 'SESSION' \| 'LOCAL' \| 'NONE' | Type of Persistence. - 'SESSION' is used for temporary persistence such as <code>sessionStorage</code>. - 'LOCAL' is used for long term persistence such as <code>localStorage</code> or <code>IndexedDB</code>. - 'NONE' is used for in-memory, or no persistence. |
+|  [type](./auth.persistence.md#persistencetype) | 'SESSION' \| 'LOCAL' \| 'NONE' \| 'COOKIE' | Type of Persistence. - 'SESSION' is used for temporary persistence such as <code>sessionStorage</code>. - 'LOCAL' is used for long term persistence such as <code>localStorage</code> or <code>IndexedDB</code>. - 'NONE' is used for in-memory, or no persistence. - 'COOKIE' is used for cookie persistence, useful for server-side rendering. |
 
 ## Persistence.type
 
-Type of Persistence. - 'SESSION' is used for temporary persistence such as `sessionStorage`<!-- -->. - 'LOCAL' is used for long term persistence such as `localStorage` or `IndexedDB`<!-- -->. - 'NONE' is used for in-memory, or no persistence.
+Type of Persistence. - 'SESSION' is used for temporary persistence such as `sessionStorage`<!-- -->. - 'LOCAL' is used for long term persistence such as `localStorage` or `IndexedDB`<!-- -->. - 'NONE' is used for in-memory, or no persistence. - 'COOKIE' is used for cookie persistence, useful for server-side rendering.
 
 <b>Signature:</b>
 
 ```typescript
-readonly type: 'SESSION' | 'LOCAL' | 'NONE';
+readonly type: 'SESSION' | 'LOCAL' | 'NONE' | 'COOKIE';
 ```

packages/auth-compat/src/auth.test.ts

@@ -65,7 +65,7 @@ describe('auth compat', () => {
     it('saves the persistence into session storage if available', async () => {
       if (typeof self !== 'undefined') {
         underlyingAuth._initializationPromise = Promise.resolve();
-        sinon.stub(underlyingAuth, '_getPersistence').returns('TEST');
+        sinon.stub(underlyingAuth, '_getPersistenceType').returns('TEST');
         sinon
           .stub(underlyingAuth, '_initializationPromise')
           .value(Promise.resolve());
@@ -97,7 +97,7 @@ describe('auth compat', () => {
           }
         } as unknown as Window);
         const setItemSpy = sinon.spy(sessionStorage, 'setItem');
-        sinon.stub(underlyingAuth, '_getPersistence').returns('TEST');
+        sinon.stub(underlyingAuth, '_getPersistenceType').returns('TEST');
         sinon
           .stub(underlyingAuth, '_initializationPromise')
           .value(Promise.resolve());

packages/auth-compat/src/persistence.ts

@@ -91,7 +91,7 @@ export async function _savePersistenceForRedirect(
     auth.name
   );
   if (session) {
-    session.setItem(key, auth._getPersistence());
+    session.setItem(key, auth._getPersistenceType());
   }
 }
 

packages/auth/index.ts

@@ -43,6 +43,7 @@ export * from './src';
 
 // persistence
 import { browserLocalPersistence } from './src/platform_browser/persistence/local_storage';
+import { browserCookiePersistence } from './src/platform_browser/persistence/cookie_storage';
 import { browserSessionPersistence } from './src/platform_browser/persistence/session_storage';
 import { indexedDBLocalPersistence } from './src/platform_browser/persistence/indexed_db';
 
@@ -83,6 +84,7 @@ import { getAuth } from './src/platform_browser';
 
 export {
   browserLocalPersistence,
+  browserCookiePersistence,
   browserSessionPersistence,
   indexedDBLocalPersistence,
   PhoneAuthProvider,

packages/auth/package.json

@@ -136,6 +136,7 @@
     "@rollup/plugin-strip": "2.1.0",
     "@types/express": "4.17.21",
     "chromedriver": "119.0.1",
+    "cookie-store": "4.0.0-next.4",
     "rollup": "2.79.2",
     "rollup-plugin-sourcemaps": "0.6.3",
     "rollup-plugin-typescript2": "0.36.0",

packages/auth/src/api/authentication/token.ts

@@ -74,7 +74,7 @@ export async function requestStsToken(
           'refresh_token': refreshToken
         }).slice(1);
         const { tokenApiHost, apiKey } = auth.config;
-        const url = _getFinalTarget(
+        const url = await _getFinalTarget(
           auth,
           tokenApiHost,
           Endpoint.TOKEN,

packages/auth/src/api/index.test.ts

@@ -509,17 +509,17 @@ describe('api/_performApiRequest', () => {
   });
 
   context('_getFinalTarget', () => {
-    it('works properly with a non-emulated environment', () => {
-      expect(_getFinalTarget(auth, 'host', '/path', 'query=test')).to.eq(
+    it('works properly with a non-emulated environment', async () => {
+      expect(await _getFinalTarget(auth, 'host', '/path', 'query=test')).to.eq(
         'mock://host/path?query=test'
       );
     });
 
-    it('works properly with an emulated environment', () => {
+    it('works properly with an emulated environment', async () => {
       (auth.config as ConfigInternal).emulator = {
         url: 'http://localhost:5000/'
       };
-      expect(_getFinalTarget(auth, 'host', '/path', 'query=test')).to.eq(
+      expect(await _getFinalTarget(auth, 'host', '/path', 'query=test')).to.eq(
         'http://localhost:5000/host/path?query=test'
       );
     });

packages/auth/src/api/index.ts

@@ -31,6 +31,8 @@ import { AuthInternal, ConfigInternal } from '../model/auth';
 import { IdTokenResponse, TaggedWithTokenResponse } from '../model/id_token';
 import { IdTokenMfaResponse } from './authentication/mfa';
 import { SERVER_ERROR_MAP, ServerError, ServerErrorMap } from './errors';
+import { PersistenceType } from '../core/persistence';
+import { CookiePersistence } from '../platform_browser/persistence/cookie_storage';
 
 export const enum HttpMethod {
   POST = 'POST',
@@ -73,6 +75,15 @@ export const enum Endpoint {
   REVOKE_TOKEN = '/v2/accounts:revokeToken'
 }
 
+const CookieAuthProxiedEndpoints: string[] = [
+  Endpoint.SIGN_IN_WITH_CUSTOM_TOKEN,
+  Endpoint.SIGN_IN_WITH_EMAIL_LINK,
+  Endpoint.SIGN_IN_WITH_IDP,
+  Endpoint.SIGN_IN_WITH_PASSWORD,
+  Endpoint.SIGN_IN_WITH_PHONE_NUMBER,
+  Endpoint.TOKEN
+];
+
 export const enum RecaptchaClientType {
   WEB = 'CLIENT_TYPE_WEB',
   ANDROID = 'CLIENT_TYPE_ANDROID',
@@ -167,7 +178,7 @@ export async function _performApiRequest<T, V>(
     }
 
     return FetchProvider.fetch()(
-      _getFinalTarget(auth, auth.config.apiHost, path, query),
+      await _getFinalTarget(auth, auth.config.apiHost, path, query),
       fetchArgs
     );
   });
@@ -257,19 +268,34 @@ export async function _performSignInRequest<T, V extends IdTokenResponse>(
   return serverResponse as V;
 }
 
-export function _getFinalTarget(
+export async function _getFinalTarget(
   auth: Auth,
   host: string,
   path: string,
   query: string
-): string {
+): Promise<string> {
   const base = `${host}${path}?${query}`;
 
-  if (!(auth as AuthInternal).config.emulator) {
-    return `${auth.config.apiScheme}://${base}`;
+  const authInternal = auth as AuthInternal;
+  const finalTarget = authInternal.config.emulator
+    ? _emulatorUrl(auth.config as ConfigInternal, base)
+    : `${auth.config.apiScheme}://${base}`;
+
+  // Cookie auth works by MiTMing the signIn and token endpoints from the developer's backend,
+  // saving the idToken and refreshToken into cookies, and then redacting the refreshToken
+  // from the response
+  if (CookieAuthProxiedEndpoints.includes(path)) {
+    // Persistence manager is async, we need to await it. We can't just wait for auth initialized
+    // here since auth initialization calls this function.
+    await authInternal._persistenceManagerAvailable;
+    if (authInternal._getPersistenceType() === PersistenceType.COOKIE) {
+      const cookiePersistence =
+        authInternal._getPersistence() as CookiePersistence;
+      return cookiePersistence._getFinalTarget(finalTarget).toString();
+    }
   }
 
-  return _emulatorUrl(auth.config as ConfigInternal, base);
+  return finalTarget;
 }
 
 export function _parseEnforcementState(

packages/auth/src/core/auth/auth_impl.ts

@@ -120,6 +120,10 @@ export class AuthImpl implements AuthInternal, _FirebaseService {
   _tenantRecaptchaConfigs: Record<string, RecaptchaConfig> = {};
   _projectPasswordPolicy: PasswordPolicyInternal | null = null;
   _tenantPasswordPolicies: Record<string, PasswordPolicyInternal> = {};
+  _resolvePersistenceManagerAvailable:
+    | ((value: void | PromiseLike<void>) => void)
+    | undefined = undefined;
+  _persistenceManagerAvailable: Promise<void>;
   readonly name: string;
 
   // Tracks the last notified UID for state change listeners to prevent
@@ -139,6 +143,11 @@ export class AuthImpl implements AuthInternal, _FirebaseService {
   ) {
     this.name = app.name;
     this.clientVersion = config.sdkClientVersion;
+    // TODO(jamesdaniels) explore less hacky way to do this, cookie authentication needs
+    // persistenceMananger to be available. see _getFinalTarget for more context
+    this._persistenceManagerAvailable = new Promise<void>(
+      resolve => (this._resolvePersistenceManagerAvailable = resolve)
+    );
   }
 
   _initializeWithPersistence(
@@ -160,6 +169,7 @@ export class AuthImpl implements AuthInternal, _FirebaseService {
         this,
         persistenceHierarchy
       );
+      this._resolvePersistenceManagerAvailable?.();
 
       if (this._deleted) {
         return;
@@ -524,10 +534,14 @@ export class AuthImpl implements AuthInternal, _FirebaseService {
     }
   }
 
-  _getPersistence(): string {
+  _getPersistenceType(): string {
     return this.assertedPersistence.persistence.type;
   }
 
+  _getPersistence(): PersistenceInternal {
+    return this.assertedPersistence.persistence;
+  }
+
   _updateErrorMap(errorMap: AuthErrorMap): void {
     this._errorFactory = new ErrorFactory<AuthErrorCode, AuthErrorParams>(
       'auth',

packages/auth/src/core/auth/initialize.test.ts

@@ -170,7 +170,7 @@ describe('core/auth/initialize', () => {
         sdkClientVersion: expectedSdkClientVersion,
         tokenApiHost: 'securetoken.googleapis.com'
       });
-      expect(auth._getPersistence()).to.eq('NONE');
+      expect(auth._getPersistenceType()).to.eq('NONE');
     });
 
     it('should set persistence', async () => {
@@ -179,7 +179,7 @@ describe('core/auth/initialize', () => {
       }) as AuthInternal;
       await auth._initializationPromise;
 
-      expect(auth._getPersistence()).to.eq('SESSION');
+      expect(auth._getPersistenceType()).to.eq('SESSION');
     });
 
     it('should set persistence with fallback', async () => {
@@ -188,7 +188,7 @@ describe('core/auth/initialize', () => {
       }) as AuthInternal;
       await auth._initializationPromise;
 
-      expect(auth._getPersistence()).to.eq('SESSION');
+      expect(auth._getPersistenceType()).to.eq('SESSION');
     });
 
     it('should set resolver', async () => {

packages/auth/src/core/persistence/index.ts

@@ -19,7 +19,8 @@ import { Persistence } from '../../model/public_types';
 export const enum PersistenceType {
   SESSION = 'SESSION',
   LOCAL = 'LOCAL',
-  NONE = 'NONE'
+  NONE = 'NONE',
+  COOKIE = 'COOKIE'
 }
 
 export type PersistedBlob = Record<string, unknown>;

packages/auth/src/core/persistence/persistence_user_manager.ts

@@ -15,6 +15,7 @@
  * limitations under the License.
  */
 
+import { getAccountInfo } from '../../api/account_management/account';
 import { ApiKey, AppName, AuthInternal } from '../../model/auth';
 import { UserInternal } from '../../model/user';
 import { PersistedBlob, PersistenceInternal } from '../persistence';
@@ -66,8 +67,22 @@ export class PersistenceUserManager {
   }
 
   async getCurrentUser(): Promise<UserInternal | null> {
-    const blob = await this.persistence._get<PersistedBlob>(this.fullUserKey);
-    return blob ? UserImpl._fromJSON(this.auth, blob) : null;
+    const blob = await this.persistence._get<PersistedBlob | string>(
+      this.fullUserKey
+    );
+    if (!blob) {
+      return null;
+    }
+    if (typeof blob === 'string') {
+      const response = await getAccountInfo(this.auth, { idToken: blob }).catch(
+        () => undefined
+      );
+      if (!response) {
+        return null;
+      }
+      return UserImpl._fromGetAccountInfoResponse(this.auth, response, blob);
+    }
+    return UserImpl._fromJSON(this.auth, blob);
   }
 
   removeCurrentUser(): Promise<void> {
@@ -140,9 +155,24 @@ export class PersistenceUserManager {
     // persistence, we will (but only if that persistence supports migration).
     for (const persistence of persistenceHierarchy) {
       try {
-        const blob = await persistence._get<PersistedBlob>(key);
+        const blob = await persistence._get<PersistedBlob | string>(key);
         if (blob) {
-          const user = UserImpl._fromJSON(auth, blob); // throws for unparsable blob (wrong format)
+          let user: UserInternal;
+          if (typeof blob === 'string') {
+            const response = await getAccountInfo(auth, {
+              idToken: blob
+            }).catch(() => undefined);
+            if (!response) {
+              break;
+            }
+            user = await UserImpl._fromGetAccountInfoResponse(
+              auth,
+              response,
+              blob
+            );
+          } else {
+            user = UserImpl._fromJSON(auth, blob); // throws for unparsable blob (wrong format)
+          }
           if (persistence !== selectedPersistence) {
             userToMigrate = user;
           }

packages/auth/src/model/auth.ts

@@ -33,6 +33,7 @@ import { UserInternal } from './user';
 import { ClientPlatform } from '../core/util/version';
 import { RecaptchaConfig } from '../platform_browser/recaptcha/recaptcha';
 import { PasswordPolicyInternal } from './password_policy';
+import { PersistenceInternal } from '../core/persistence';
 
 export type AppName = string;
 export type ApiKey = string;
@@ -71,6 +72,7 @@ export interface AuthInternal extends Auth {
   _canInitEmulator: boolean;
   _isInitialized: boolean;
   _initializationPromise: Promise<void> | null;
+  _persistenceManagerAvailable: Promise<void>;
   _updateCurrentUser(user: UserInternal | null): Promise<void>;
 
   _onStorageEvent(): void;
@@ -86,7 +88,8 @@ export interface AuthInternal extends Auth {
   _key(): string;
   _startProactiveRefresh(): void;
   _stopProactiveRefresh(): void;
-  _getPersistence(): string;
+  _getPersistenceType(): string;
+  _getPersistence(): PersistenceInternal;
   _getRecaptchaConfig(): RecaptchaConfig | null;
   _getPasswordPolicyInternal(): PasswordPolicyInternal | null;
   _updatePasswordPolicy(): Promise<void>;

packages/auth/src/model/public_types.ts

@@ -341,8 +341,9 @@ export interface Persistence {
    * - 'SESSION' is used for temporary persistence such as `sessionStorage`.
    * - 'LOCAL' is used for long term persistence such as `localStorage` or `IndexedDB`.
    * - 'NONE' is used for in-memory, or no persistence.
+   * - 'COOKIE' is used for cookie persistence, useful for server-side rendering.
    */
-  readonly type: 'SESSION' | 'LOCAL' | 'NONE';
+  readonly type: 'SESSION' | 'LOCAL' | 'NONE' | 'COOKIE';
 }
 
 /**

packages/auth/src/platform_browser/persistence/cookie_storage.ts

@@ -0,0 +1,166 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Persistence } from '../../model/public_types';
+import type { CookieChangeEvent } from 'cookie-store';
+
+const POLLING_INTERVAL_MS = 1_000;
+
+import {
+  PersistenceInternal,
+  PersistenceType,
+  PersistenceValue,
+  StorageEventListener
+} from '../../core/persistence';
+
+// Pull a cookie value from document.cookie
+function getDocumentCookie(name: string): string | null {
+  const escapedName = name.replace(/[\\^$.*+?()[\]{}|]/g, '\\$&');
+  const matcher = RegExp(`${escapedName}=([^;]+)`);
+  return document.cookie.match(matcher)?.[1] ?? null;
+}
+
+// Produce a sanitized cookie name from the persistence key
+function getCookieName(key: string): string {
+  // __HOST- doesn't work in localhost https://issues.chromium.org/issues/40196122 but it has
+  // desirable security properties, so lets use a different cookie name while in dev-mode.
+  // Already checked isSecureContext in _isAvailable, so if it's http we're hitting local.
+  const isDevMode = window.location.protocol === 'http:';
+  return `${isDevMode ? '__dev_' : '__HOST-'}FIREBASE_${key.split(':')[3]}`;
+}
+
+export class CookiePersistence implements PersistenceInternal {
+  static type: 'COOKIE' = 'COOKIE';
+  readonly type = PersistenceType.COOKIE;
+  listenerUnsubscribes: Map<StorageEventListener, () => void> = new Map();
+
+  // used to get the URL to the backend to proxy to
+  _getFinalTarget(originalUrl: string): URL | string {
+    if (typeof window === undefined) {
+      return originalUrl;
+    }
+    const url = new URL(`${window.location.origin}/__cookies__`);
+    url.searchParams.set('finalTarget', originalUrl);
+    return url;
+  }
+
+  // To be a usable persistence method in a chain browserCookiePersistence ensures that
+  // prerequisites have been met, namely that we're in a secureContext, navigator and document are
+  // available and cookies are enabled. Not all UAs support these method, so fallback accordingly.
+  async _isAvailable(): Promise<boolean> {
+    if (typeof isSecureContext === 'boolean' && !isSecureContext) {
+      return false;
+    }
+    if (typeof navigator === 'undefined' || typeof document === 'undefined') {
+      return false;
+    }
+    return navigator.cookieEnabled ?? true;
+  }
+
+  // Set should be a noop as we expect middleware to handle this
+  async _set(_key: string, _value: PersistenceValue): Promise<void> {
+    return;
+  }
+
+  // Attempt to get the cookie from cookieStore, fallback to document.cookie
+  async _get<T extends PersistenceValue>(key: string): Promise<T | null> {
+    if (!this._isAvailable()) {
+      return null;
+    }
+    const name = getCookieName(key);
+    if (window.cookieStore) {
+      const cookie = await window.cookieStore.get(name);
+      return cookie?.value as T;
+    }
+    return getDocumentCookie(name) as T;
+  }
+
+  // Log out by overriding the idToken with a sentinel value of ""
+  async _remove(key: string): Promise<void> {
+    if (!this._isAvailable()) {
+      return;
+    }
+    // To make sure we don't hit signout over and over again, only do this operation if we need to
+    // with the logout sentinel value of "" this can cause race conditions. Unnecessary set-cookie
+    // headers will reduce CDN hit rates too.
+    const existingValue = await this._get(key);
+    if (!existingValue) {
+      return;
+    }
+    const name = getCookieName(key);
+    document.cookie = `${name}=;Max-Age=34560000;Partitioned;Secure;SameSite=Strict;Path=/;Priority=High`;
+    await fetch(`/__cookies__`, { method: 'DELETE' }).catch(() => undefined);
+  }
+
+  // Listen for cookie changes, both cookieStore and fallback to polling document.cookie
+  _addListener(key: string, listener: StorageEventListener): void {
+    if (!this._isAvailable()) {
+      return;
+    }
+    const name = getCookieName(key);
+    if (window.cookieStore) {
+      const cb = ((event: CookieChangeEvent): void => {
+        const changedCookie = event.changed.find(
+          change => change.name === name
+        );
+        if (changedCookie) {
+          listener(changedCookie.value as PersistenceValue);
+        }
+        const deletedCookie = event.deleted.find(
+          change => change.name === name
+        );
+        if (deletedCookie) {
+          listener(null);
+        }
+      }) as EventListener;
+      const unsubscribe = (): void =>
+        window.cookieStore.removeEventListener('change', cb);
+      this.listenerUnsubscribes.set(listener, unsubscribe);
+      return window.cookieStore.addEventListener('change', cb as EventListener);
+    }
+    let lastValue = getDocumentCookie(name);
+    const interval = setInterval(() => {
+      const currentValue = getDocumentCookie(name);
+      if (currentValue !== lastValue) {
+        listener(currentValue as PersistenceValue | null);
+        lastValue = currentValue;
+      }
+    }, POLLING_INTERVAL_MS);
+    const unsubscribe = (): void => clearInterval(interval);
+    this.listenerUnsubscribes.set(listener, unsubscribe);
+  }
+
+  _removeListener(_key: string, listener: StorageEventListener): void {
+    const unsubscribe = this.listenerUnsubscribes.get(listener);
+    if (!unsubscribe) {
+      return;
+    }
+    unsubscribe();
+    this.listenerUnsubscribes.delete(listener);
+  }
+}
+
+/**
+ * An implementation of {@link Persistence} of type `COOKIE`, for use on the client side in
+ * applications leveraging hybrid rendering and middleware.
+ *
+ * @remarks This persistence method requires companion middleware to function, such as that provided
+ * by {@link https://firebaseopensource.com/projects/firebaseextended/reactfire/ | ReactFire} for
+ * NextJS.
+ * @beta
+ */
+export const browserCookiePersistence: Persistence = CookiePersistence;

packages/auth/src/platform_node/index.ts

@@ -81,6 +81,7 @@ class FailClass {
 
 export const browserLocalPersistence = inMemoryPersistence;
 export const browserSessionPersistence = inMemoryPersistence;
+export const browserCookiePersistence = inMemoryPersistence;
 export const indexedDBLocalPersistence = inMemoryPersistence;
 export const browserPopupRedirectResolver = NOT_AVAILABLE_ERROR;
 export const PhoneAuthProvider = FailClass;

yarn.lock

@@ -5875,6 +5875,11 @@ [email protected]:
   resolved "https://registry.npmjs.org/cookie-signature/-/cookie-signature-1.0.6.tgz#e303a882b342cc3ee8ca513a79999734dab3ae2c"
   integrity sha512-QADzlaHc8icV8I7vbaJXJwod9HWYp8uCqf1xa4OfNu1T7JVxQIrUgOWtHdNDtPiywmFbiS12VjotIXLrKM3orQ==
 
+[email protected]:
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