initializeApp method

@override Future<FirebaseAppPlatform> initializeApp({ String? name, FirebaseOptions? options, })

Initializes a Firebase app instance.

Internally initializes core if it is not yet ready.

Implementation

@override
Future<FirebaseAppPlatform> initializeApp({
  String? name,
  FirebaseOptions? options,
}) async {
  // Ensure that core has been initialized on the first usage of
  // initializeApp
  if (!isCoreInitialized) {
    await _initializeCore();
  }

  // If no name is provided, attempt to get the default Firebase app instance.
  // If no instance is available, the user has not set up Firebase correctly for
  // their platform.
  if (name == null || name == defaultFirebaseAppName) {
    MethodChannelFirebaseApp? defaultApp =
        appInstances[defaultFirebaseAppName];
    FirebaseOptions? _options = options;
    // If no default app and no options are provided then
    // attempt to read options from native resources on Android,
    // e.g. this calls to `FirebaseOptions.fromResource(context)`.
    if (defaultTargetPlatform == TargetPlatform.android &&
        defaultApp == null &&
        _options == null) {
      final options = await api.optionsFromResource();
      _options = FirebaseOptions.fromPigeon(options);
    }

    // If no options are present & no default app has been setup, the user is
    // trying to initialize default from Dart
    if (defaultApp == null && _options != null) {
      _initializeFirebaseAppFromMap(await api.initializeApp(
          defaultFirebaseAppName,
          PigeonFirebaseOptions(
            apiKey: _options.apiKey,
            appId: _options.appId,
            messagingSenderId: _options.messagingSenderId,
            projectId: _options.projectId,
            authDomain: _options.authDomain,
            databaseURL: _options.databaseURL,
            storageBucket: _options.storageBucket,
            measurementId: _options.measurementId,
            trackingId: _options.trackingId,
            deepLinkURLScheme: _options.deepLinkURLScheme,
            androidClientId: _options.androidClientId,
            iosClientId: _options.iosClientId,
            iosBundleId: _options.iosBundleId,
            appGroupId: _options.appGroupId,
          )));
      defaultApp = appInstances[defaultFirebaseAppName];
    }

    // If there is no native default app and the user didn't provide options to
    // create one, throw.
    if (defaultApp == null && _options == null) {
      throw coreNotInitialized();
    }

    // If there is a native default app and the user provided options do a soft
    // check to see if options are roughly identical (so we don't unnecessarily
    // throw on minor differences such as platform specific keys missing
    // e.g. hot reloads/restarts).
    if (defaultApp != null && _options != null) {
      if (_options.apiKey != defaultApp.options.apiKey ||
          (_options.databaseURL != null &&
              _options.databaseURL != defaultApp.options.databaseURL) ||
          (_options.storageBucket != null &&
              _options.storageBucket != defaultApp.options.storageBucket)) {
        // Options are different; throw.
        throw duplicateApp(defaultFirebaseAppName);
      }
      // Options are roughly the same; so we'll return the existing app.
    }

    return appInstances[defaultFirebaseAppName]!;
  }

  assert(
    options != null,
    'FirebaseOptions cannot be null when creating a secondary Firebase app.',
  );

  // Check whether the app has already been initialized
  if (appInstances.containsKey(name)) {
    final existingApp = appInstances[name]!;
    if (options!.apiKey != existingApp.options.apiKey ||
        (options.databaseURL != null &&
            options.databaseURL != existingApp.options.databaseURL) ||
        (options.storageBucket != null &&
            options.storageBucket != existingApp.options.storageBucket)) {
      // Options are different; throw.
      throw duplicateApp(name);
    } else {
      return existingApp;
    }
  }

  _initializeFirebaseAppFromMap(await api.initializeApp(
      name,
      PigeonFirebaseOptions(
        apiKey: options!.apiKey,
        appId: options.appId,
        messagingSenderId: options.messagingSenderId,
        projectId: options.projectId,
        authDomain: options.authDomain,
        databaseURL: options.databaseURL,
        storageBucket: options.storageBucket,
        measurementId: options.measurementId,
        trackingId: options.trackingId,
        deepLinkURLScheme: options.deepLinkURLScheme,
        androidClientId: options.androidClientId,
        iosClientId: options.iosClientId,
        iosBundleId: options.iosBundleId,
        appGroupId: options.appGroupId,
      )));
  return appInstances[name]!;
}