modular autoinit (#6526)

Add functionality to read config from __FIREBASE_DEFAULTS__ global or env variable. See go/firebase-api-client-autoinit

.changeset/mighty-insects-judge.md

@@ -0,0 +1,13 @@
+---
+'@firebase/app': minor
+'@firebase/app-types': minor
+'@firebase/util': minor
+'@firebase/auth': patch
+'@firebase/database': patch
+'@firebase/firestore': patch
+'@firebase/functions': patch
+'@firebase/storage': patch
+'firebase': minor
+---
+
+Add functionality to auto-initialize project config and emulator settings from global defaults provided by framework tooling.

common/api-review/app.api.md

@@ -93,6 +93,9 @@ export function initializeApp(options: FirebaseOptions, name?: string): Firebase
 // @public
 export function initializeApp(options: FirebaseOptions, config?: FirebaseAppSettings): FirebaseApp;
 
+// @public
+export function initializeApp(): FirebaseApp;
+
 // @public
 export function onLog(logCallback: LogCallback | null, options?: LogOptions): void;
 

common/api-review/firestore.api.md

@@ -262,10 +262,10 @@ export function getDocsFromCache<T>(query: Query<T>): Promise<QuerySnapshot<T>>;
 export function getDocsFromServer<T>(query: Query<T>): Promise<QuerySnapshot<T>>;
 
 // @public
-export function getFirestore(): Firestore;
+export function getFirestore(app: FirebaseApp): Firestore;
 
 // @public
-export function getFirestore(app: FirebaseApp): Firestore;
+export function getFirestore(): Firestore;
 
 // @public
 export function increment(n: number): FieldValue;

common/api-review/util.api.md

@@ -173,11 +173,28 @@ export function errorPrefix(fnName: string, argName: string): string;
 // @public (undocumented)
 export type Executor<T> = (observer: Observer<T>) => void;
 
+// @public
+export type ExperimentalKey = 'authTokenSyncURL' | 'authIdTokenMaxAge';
+
 // Warning: (ae-missing-release-tag) "extractQuerystring" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
 // @public
 export function extractQuerystring(url: string): string;
 
+// @public
+export interface FirebaseDefaults {
+    // (undocumented)
+    [key: string]: unknown;
+    // (undocumented)
+    _authIdTokenMaxAge?: number;
+    // (undocumented)
+    _authTokenSyncURL?: string;
+    // (undocumented)
+    config?: Record<string, string>;
+    // (undocumented)
+    emulatorHosts?: Record<string, string>;
+}
+
 // Warning: (ae-missing-release-tag) "FirebaseError" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
 // @public (undocumented)
@@ -195,6 +212,15 @@ export class FirebaseError extends Error {
 // @public
 export type FirebaseSignInProvider = 'custom' | 'email' | 'password' | 'phone' | 'anonymous' | 'google.com' | 'facebook.com' | 'github.com' | 'twitter.com' | 'microsoft.com' | 'apple.com';
 
+// @public
+export const getDefaultAppConfig: () => Record<string, string> | undefined;
+
+// @public
+export const getDefaultEmulatorHost: (productName: string) => string | undefined;
+
+// @public
+export const getExperimentalSetting: <T extends ExperimentalKey>(name: T) => FirebaseDefaults[`_${T}`];
+
 // Warning: (ae-missing-release-tag) "getGlobal" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
 // @public

packages/app/src/api.ts

@@ -39,7 +39,7 @@ import {
   LogOptions,
   setUserLogHandler
 } from '@firebase/logger';
-import { deepEqual } from '@firebase/util';
+import { deepEqual, getDefaultAppConfig } from '@firebase/util';
 
 export { FirebaseError } from '@firebase/util';
 
@@ -110,10 +110,18 @@ export function initializeApp(
   options: FirebaseOptions,
   config?: FirebaseAppSettings
 ): FirebaseApp;
+/**
+ * Creates and initializes a FirebaseApp instance.
+ *
+ * @public
+ */
+export function initializeApp(): FirebaseApp;
 export function initializeApp(
-  options: FirebaseOptions,
+  _options?: FirebaseOptions,
   rawConfig = {}
 ): FirebaseApp {
+  let options = _options;
+
   if (typeof rawConfig !== 'object') {
     const name = rawConfig;
     rawConfig = { name };
@@ -132,6 +140,12 @@ export function initializeApp(
     });
   }
 
+  options ||= getDefaultAppConfig();
+
+  if (!options) {
+    throw ERROR_FACTORY.create(AppError.NO_OPTIONS);
+  }
+
   const existingApp = _apps.get(name) as FirebaseAppImpl;
   if (existingApp) {
     // return the existing app if options and config deep equal the ones in the existing app.
@@ -188,6 +202,9 @@ export function initializeApp(
  */
 export function getApp(name: string = DEFAULT_ENTRY_NAME): FirebaseApp {
   const app = _apps.get(name);
+  if (!app && name === DEFAULT_ENTRY_NAME) {
+    return initializeApp();
+  }
   if (!app) {
     throw ERROR_FACTORY.create(AppError.NO_APP, { appName: name });
   }

packages/app/src/errors.ts

@@ -22,6 +22,7 @@ export const enum AppError {
   BAD_APP_NAME = 'bad-app-name',
   DUPLICATE_APP = 'duplicate-app',
   APP_DELETED = 'app-deleted',
+  NO_OPTIONS = 'no-options',
   INVALID_APP_ARGUMENT = 'invalid-app-argument',
   INVALID_LOG_ARGUMENT = 'invalid-log-argument',
   IDB_OPEN = 'idb-open',
@@ -38,6 +39,8 @@ const ERRORS: ErrorMap<AppError> = {
   [AppError.DUPLICATE_APP]:
     "Firebase App named '{$appName}' already exists with different options or config",
   [AppError.APP_DELETED]: "Firebase App named '{$appName}' already deleted",
+  [AppError.NO_OPTIONS]:
+    'Need to provide options, when not being deployed to hosting via source.',
   [AppError.INVALID_APP_ARGUMENT]:
     'firebase.{$appName}() takes either no argument or a ' +
     'Firebase App instance.',

packages/auth/src/platform_browser/index.ts

@@ -17,14 +17,50 @@
 
 import { FirebaseApp, getApp, _getProvider } from '@firebase/app';
 
-import { initializeAuth } from '..';
+import {
+  initializeAuth,
+  beforeAuthStateChanged,
+  onIdTokenChanged,
+  connectAuthEmulator
+} from '..';
 import { registerAuth } from '../core/auth/register';
 import { ClientPlatform } from '../core/util/version';
 import { browserLocalPersistence } from './persistence/local_storage';
 import { browserSessionPersistence } from './persistence/session_storage';
 import { indexedDBLocalPersistence } from './persistence/indexed_db';
 import { browserPopupRedirectResolver } from './popup_redirect';
-import { Auth } from '../model/public_types';
+import { Auth, User } from '../model/public_types';
+import { getDefaultEmulatorHost, getExperimentalSetting } from '@firebase/util';
+
+const DEFAULT_ID_TOKEN_MAX_AGE = 5 * 60;
+const authIdTokenMaxAge =
+  getExperimentalSetting('authIdTokenMaxAge') || DEFAULT_ID_TOKEN_MAX_AGE;
+
+let lastPostedIdToken: string | undefined | null = null;
+
+const mintCookieFactory = (url: string) => async (user: User | null) => {
+  const idTokenResult = user && (await user.getIdTokenResult());
+  const idTokenAge =
+    idTokenResult &&
+    (new Date().getTime() - Date.parse(idTokenResult.issuedAtTime)) / 1_000;
+  if (idTokenAge && idTokenAge > authIdTokenMaxAge) {
+    return;
+  }
+  // Specifically trip null => undefined when logged out, to delete any existing cookie
+  const idToken = idTokenResult?.token;
+  if (lastPostedIdToken === idToken) {
+    return;
+  }
+  lastPostedIdToken = idToken;
+  await fetch(url, {
+    method: idToken ? 'POST' : 'DELETE',
+    headers: idToken
+      ? {
+          'Authorization': `Bearer ${idToken}`
+        }
+      : {}
+  });
+};
 
 /**
  * Returns the Auth instance associated with the provided {@link @firebase/app#FirebaseApp}.
@@ -41,14 +77,30 @@ export function getAuth(app: FirebaseApp = getApp()): Auth {
     return provider.getImmediate();
   }
 
-  return initializeAuth(app, {
+  const auth = initializeAuth(app, {
     popupRedirectResolver: browserPopupRedirectResolver,
     persistence: [
       indexedDBLocalPersistence,
       browserLocalPersistence,
       browserSessionPersistence
     ]
   });
+
+  const authTokenSyncUrl = getExperimentalSetting('authTokenSyncURL');
+  if (authTokenSyncUrl) {
+    const mintCookie = mintCookieFactory(authTokenSyncUrl);
+    beforeAuthStateChanged(auth, mintCookie, () =>
+      mintCookie(auth.currentUser)
+    );
+    onIdTokenChanged(auth, user => mintCookie(user));
+  }
+
+  const authEmulatorHost = getDefaultEmulatorHost('auth');
+  if (authEmulatorHost) {
+    connectAuthEmulator(auth, `http://${authEmulatorHost}`);
+  }
+
+  return auth;
 }
 
 registerAuth(ClientPlatform.BROWSER);

packages/auth/src/platform_node/index.ts

@@ -21,13 +21,14 @@ import { _createError } from '../core/util/assert';
 import { FirebaseApp, getApp, _getProvider } from '@firebase/app';
 import { Auth } from '../model/public_types';
 
-import { initializeAuth, inMemoryPersistence } from '..';
+import { initializeAuth, inMemoryPersistence, connectAuthEmulator } from '..';
 import { registerAuth } from '../core/auth/register';
 import { ClientPlatform } from '../core/util/version';
 import { AuthImpl } from '../core/auth/auth_impl';
 
 import { FetchProvider } from '../core/util/fetch_provider';
 import * as fetchImpl from 'node-fetch';
+import { getDefaultEmulatorHost } from '@firebase/util';
 
 // Initialize the fetch polyfill, the types are slightly off so just cast and hope for the best
 FetchProvider.initialize(
@@ -46,7 +47,14 @@ export function getAuth(app: FirebaseApp = getApp()): Auth {
     return provider.getImmediate();
   }
 
-  return initializeAuth(app);
+  const auth = initializeAuth(app);
+
+  const authEmulatorHost = getDefaultEmulatorHost('auth');
+  if (authEmulatorHost) {
+    connectAuthEmulator(auth, `http://${authEmulatorHost}`);
+  }
+
+  return auth;
 }
 
 registerAuth(ClientPlatform.NODE);

packages/database/src/api/Database.ts

@@ -27,7 +27,8 @@ import { Provider } from '@firebase/component';
 import {
   getModularInstance,
   createMockUserToken,
-  EmulatorMockTokenOptions
+  EmulatorMockTokenOptions,
+  getDefaultEmulatorHost
 } from '@firebase/util';
 
 import { AppCheckTokenProvider } from '../core/AppCheckTokenProvider';
@@ -316,9 +317,15 @@ export function getDatabase(
   app: FirebaseApp = getApp(),
   url?: string
 ): Database {
-  return _getProvider(app, 'database').getImmediate({
+  const db = _getProvider(app, 'database').getImmediate({
     identifier: url
   }) as Database;
+  const databaseEmulatorHost = getDefaultEmulatorHost('database');
+  if (databaseEmulatorHost) {
+    const [host, port] = databaseEmulatorHost.split(':');
+    connectDatabaseEmulator(db, host, parseInt(port, 10));
+  }
+  return db;
 }
 
 /**

packages/firestore/externs.json

@@ -26,6 +26,7 @@
     "packages/logger/dist/src/logger.d.ts",
     "packages/webchannel-wrapper/src/index.d.ts",
     "packages/util/dist/src/crypt.d.ts",
+    "packages/util/dist/src/defaults.d.ts",
     "packages/util/dist/src/emulator.d.ts",
     "packages/util/dist/src/environment.d.ts",
     "packages/util/dist/src/compat.d.ts",

packages/firestore/src/api/database.ts

@@ -15,14 +15,13 @@
  * limitations under the License.
  */
 
-// eslint-disable-next-line import/no-extraneous-dependencies
 import {
   _getProvider,
   _removeServiceInstance,
   FirebaseApp,
   getApp
 } from '@firebase/app';
-import { deepEqual } from '@firebase/util';
+import { deepEqual, getDefaultEmulatorHost } from '@firebase/util';
 
 import { User } from '../auth/user';
 import {
@@ -43,7 +42,10 @@ import {
   setOnlineComponentProvider
 } from '../core/firestore_client';
 import { makeDatabaseInfo } from '../lite-api/components';
-import { Firestore as LiteFirestore } from '../lite-api/database';
+import {
+  Firestore as LiteFirestore,
+  connectFirestoreEmulator
+} from '../lite-api/database';
 import { Query } from '../lite-api/reference';
 import {
   indexedDbClearPersistence,
@@ -186,14 +188,6 @@ export function initializeFirestore(
   });
 }
 
-/**
- * Returns the existing default {@link Firestore} instance that is associated with the
- * default {@link @firebase/app#FirebaseApp}. If no instance exists, initializes a new
- * instance with default settings.
- *
- * @returns The {@link Firestore} instance of the provided app.
- */
-export function getFirestore(): Firestore;
 /**
  * Returns the existing default {@link Firestore} instance that is associated with the
  * provided {@link @firebase/app#FirebaseApp}. If no instance exists, initializes a new
@@ -215,7 +209,15 @@ export function getFirestore(app: FirebaseApp): Firestore;
  */
 export function getFirestore(databaseId: string): Firestore;
 /**
- * Returns the existing {@link Firestore} instance that is associated with the
+ * Returns the existing default {@link Firestore} instance that is associated with the
+ * default {@link @firebase/app#FirebaseApp}. If no instance exists, initializes a new
+ * instance with default settings.
+ *
+ * @returns The {@link Firestore} instance of the provided app.
+ */
+export function getFirestore(): Firestore;
+/**
+ * Returns the existing default {@link Firestore} instance that is associated with the
  * provided {@link @firebase/app#FirebaseApp}. If no instance exists, initializes a new
  * instance with default settings.
  *
@@ -236,9 +238,17 @@ export function getFirestore(
     typeof appOrDatabaseId === 'string'
       ? appOrDatabaseId
       : optionalDatabaseId || DEFAULT_DATABASE_NAME;
-  return _getProvider(app, 'firestore').getImmediate({
+  const db = _getProvider(app, 'firestore').getImmediate({
     identifier: databaseId
   }) as Firestore;
+  if (!db._initialized) {
+    const firestoreEmulatorHost = getDefaultEmulatorHost('firestore');
+    if (firestoreEmulatorHost) {
+      const [host, port] = firestoreEmulatorHost.split(':');
+      connectFirestoreEmulator(db, host, parseInt(port, 10));
+    }
+  }
+  return db;
 }
 
 /**