Add auth listener implementation, add user.reload() (#2961)

Author: sam-gc

packages-exp/auth-exp/src/api/account_management/account.ts

@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 
-import { Endpoint, HttpMethod, performApiRequest } from '..';
+import { Endpoint, HttpMethod, performApiRequest } from '../';
 import { Auth } from '../../model/auth';
 import { APIMFAInfo } from '../../model/id_token';
 
@@ -74,7 +74,7 @@ export interface APIUserInfo {
   createdAt?: number;
   tenantId?: string;
   passwordHash?: string;
-  providerUserInfo: ProviderUserInfo[];
+  providerUserInfo?: ProviderUserInfo[];
   mfaInfo?: APIMFAInfo[];
 }
 

packages-exp/auth-exp/src/core/auth/auth_impl.test.ts

@@ -24,6 +24,7 @@ import { FirebaseError } from '@firebase/util';
 
 import { testUser } from '../../../test/mock_auth';
 import { Auth } from '../../model/auth';
+import { User } from '../../model/user';
 import { Persistence } from '../persistence';
 import { browserLocalPersistence } from '../persistence/browser';
 import { inMemoryPersistence } from '../persistence/in_memory';
@@ -117,6 +118,139 @@ describe('AuthImpl', () => {
       );
     });
   });
+
+  describe('change listeners', () => {
+    // // Helpers to convert auth state change results to promise
+    // function onAuthStateChange(callback: NextFn<User|null>)
+
+    it('immediately calls authStateChange if initialization finished', done => {
+      const user = testUser('uid');
+      auth.currentUser = user;
+      auth._isInitialized = true;
+      auth.onAuthStateChanged(user => {
+        expect(user).to.eq(user);
+        done();
+      });
+    });
+
+    it('immediately calls idTokenChange if initialization finished', done => {
+      const user = testUser('uid');
+      auth.currentUser = user;
+      auth._isInitialized = true;
+      auth.onIdTokenChange(user => {
+        expect(user).to.eq(user);
+        done();
+      });
+    });
+
+    it('immediate callback is done async', () => {
+      auth._isInitialized = true;
+      let callbackCalled = false;
+      auth.onIdTokenChange(() => {
+        callbackCalled = true;
+      });
+
+      expect(callbackCalled).to.be.false;
+    });
+
+    describe('user logs in/out, tokens refresh', () => {
+      let user: User;
+      let authStateCallback: sinon.SinonSpy;
+      let idTokenCallback: sinon.SinonSpy;
+
+      beforeEach(() => {
+        user = testUser('uid');
+        authStateCallback = sinon.spy();
+        idTokenCallback = sinon.spy();
+      });
+
+      context('initially currentUser is null', () => {
+        beforeEach(async () => {
+          auth.onAuthStateChanged(authStateCallback);
+          auth.onIdTokenChange(idTokenCallback);
+          await auth.updateCurrentUser(null);
+          authStateCallback.resetHistory();
+          idTokenCallback.resetHistory();
+        });
+
+        it('onAuthStateChange triggers on log in', async () => {
+          await auth.updateCurrentUser(user);
+          expect(authStateCallback).to.have.been.calledWith(user);
+        });
+
+        it('onIdTokenChange triggers on log in', async () => {
+          await auth.updateCurrentUser(user);
+          expect(idTokenCallback).to.have.been.calledWith(user);
+        });
+      });
+
+      context('initially currentUser is user', () => {
+        beforeEach(async () => {
+          auth.onAuthStateChanged(authStateCallback);
+          auth.onIdTokenChange(idTokenCallback);
+          await auth.updateCurrentUser(user);
+          authStateCallback.resetHistory();
+          idTokenCallback.resetHistory();
+        });
+
+        it('onAuthStateChange triggers on log out', async () => {
+          await auth.updateCurrentUser(null);
+          expect(authStateCallback).to.have.been.calledWith(null);
+        });
+
+        it('onIdTokenChange triggers on log out', async () => {
+          await auth.updateCurrentUser(null);
+          expect(idTokenCallback).to.have.been.calledWith(null);
+        });
+
+        it('onAuthStateChange does not trigger for user props change', async () => {
+          user.refreshToken = 'hey look I changed';
+          await auth.updateCurrentUser(user);
+          expect(authStateCallback).not.to.have.been.called;
+        });
+
+        it('onIdTokenChange triggers for user props change', async () => {
+          user.refreshToken = 'hey look I changed';
+          await auth.updateCurrentUser(user);
+          expect(idTokenCallback).to.have.been.calledWith(user);
+        });
+
+        it('onAuthStateChange triggers if uid changes', async () => {
+          const newUser = testUser('different-uid');
+          await auth.updateCurrentUser(newUser);
+          expect(authStateCallback).to.have.been.calledWith(newUser);
+        });
+      });
+
+      it('onAuthStateChange works for multiple listeners', async () => {
+        const cb1 = sinon.spy();
+        const cb2 = sinon.spy();
+        auth.onAuthStateChanged(cb1);
+        auth.onAuthStateChanged(cb2);
+        await auth.updateCurrentUser(null);
+        cb1.resetHistory();
+        cb2.resetHistory();
+
+        await auth.updateCurrentUser(user);
+        expect(cb1).to.have.been.calledWith(user);
+        expect(cb2).to.have.been.calledWith(user);
+      });
+
+      it('onIdTokenChange works for multiple listeners', async () => {
+        const cb1 = sinon.spy();
+        const cb2 = sinon.spy();
+        auth.onIdTokenChange(cb1);
+        auth.onIdTokenChange(cb2);
+        await auth.updateCurrentUser(null);
+        cb1.resetHistory();
+        cb2.resetHistory();
+
+        await auth.updateCurrentUser(user);
+        expect(cb1).to.have.been.calledWith(user);
+        expect(cb2).to.have.been.calledWith(user);
+      });
+    });
+  });
 });
 
 describe('initializeAuth', () => {

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

@@ -17,8 +17,17 @@
 
 import { getApp } from '@firebase/app-exp';
 import { FirebaseApp } from '@firebase/app-types-exp';
-
-import { Auth, Config, Dependencies } from '../../model/auth';
+import {
+  CompleteFn,
+  createSubscribe,
+  ErrorFn,
+  NextFn,
+  Observer,
+  Subscribe,
+  Unsubscribe
+} from '@firebase/util';
+
+import { Auth, Config, Dependencies, NextOrObserver } from '../../model/auth';
 import { User } from '../../model/user';
 import { AuthErrorCode } from '../errors';
 import { Persistence } from '../persistence';
@@ -37,6 +46,13 @@ class AuthImpl implements Auth {
   currentUser: User | null = null;
   private operations = Promise.resolve();
   private persistenceManager?: PersistenceUserManager;
+  private authStateSubscription = new Subscription<User>(this);
+  private idTokenSubscription = new Subscription<User>(this);
+  _isInitialized = false;
+
+  // Tracks the last notified UID for state change listeners to prevent
+  // repeated calls to the callbacks
+  private lastNotifiedUid: string | undefined = undefined;
 
   constructor(
     public readonly name: string,
@@ -57,6 +73,9 @@ class AuthImpl implements Auth {
       if (storedUser) {
         await this.directlySetCurrentUser(storedUser);
       }
+
+      this._isInitialized = true;
+      this._notifyStateListeners();
     });
   }
 
@@ -74,6 +93,68 @@ class AuthImpl implements Auth {
     });
   }
 
+  onAuthStateChanged(
+    nextOrObserver: NextOrObserver<User>,
+    error?: ErrorFn,
+    completed?: CompleteFn
+  ): Unsubscribe {
+    return this.registerStateListener(
+      this.authStateSubscription,
+      nextOrObserver,
+      error,
+      completed
+    );
+  }
+
+  onIdTokenChange(
+    nextOrObserver: NextOrObserver<User>,
+    error?: ErrorFn,
+    completed?: CompleteFn
+  ): Unsubscribe {
+    return this.registerStateListener(
+      this.idTokenSubscription,
+      nextOrObserver,
+      error,
+      completed
+    );
+  }
+
+  _notifyStateListeners(): void {
+    if (!this._isInitialized) {
+      return;
+    }
+
+    this.idTokenSubscription.next(this.currentUser);
+
+    if (this.lastNotifiedUid !== this.currentUser?.uid) {
+      this.lastNotifiedUid = this.currentUser?.uid;
+      this.authStateSubscription.next(this.currentUser);
+    }
+  }
+
+  private registerStateListener(
+    subscription: Subscription<User>,
+    nextOrObserver: NextOrObserver<User>,
+    error?: ErrorFn,
+    completed?: CompleteFn
+  ): Unsubscribe {
+    if (this._isInitialized) {
+      const cb =
+        typeof nextOrObserver === 'function'
+          ? nextOrObserver
+          : nextOrObserver.next;
+      // The callback needs to be called asynchronously per the spec.
+      // eslint-disable-next-line @typescript-eslint/no-floating-promises
+      Promise.resolve().then(() => cb(this.currentUser));
+    }
+
+    if (typeof nextOrObserver === 'function') {
+      return subscription.addObserver(nextOrObserver, error, completed);
+    } else {
+      return subscription.addObserver(nextOrObserver);
+    }
+  }
+
   /**
    * Unprotected (from race conditions) method to set the current user. This
    * should only be called from within a queued callback. This is necessary
@@ -87,6 +168,8 @@ class AuthImpl implements Auth {
     } else {
       await this.assertedPersistence.removeCurrentUser();
     }
+
+    this._notifyStateListeners();
   }
 
   private queue(action: AsyncAction): Promise<void> {
@@ -122,3 +205,18 @@ export function initializeAuth(
 
   return new AuthImpl(app.name, config, hierarchy);
 }
+
+/** Helper class to wrap subscriber logic */
+class Subscription<T> {
+  private observer: Observer<T | null> | null = null;
+  readonly addObserver: Subscribe<T | null> = createSubscribe(
+    observer => (this.observer = observer)
+  );
+
+  constructor(readonly auth: Auth) {}
+
+  get next(): NextFn<T | null> {
+    assert(this.observer, this.auth.name);
+    return this.observer.next.bind(this.observer);
+  }
+}