🐛 [firebase_core_web] Expected a value of type 'String', but got one of type 'Null'

[Patrick386]

After upgrading to Flutter version 3.16.9, I'm encountering errors, and I'm unable to identify the cause.

cloud_firestore_platform_interface: ^6.1.0
firebase_core_platform_interface: ^5.0.0
firebase_storage: ^11.6.0

firebase_auth: ^4.16.0
firebase_ui_auth: ^1.12.1
firebase_auth_web: ^5.8.13

Launching lib/main.dart on Chrome in debug mode...
Waiting for connection from debug service on Chrome...
This app is linked to the debug service: ws://127.0.0.1:52720/FaxQR7KmzDc=/ws
Debug service listening on ws://127.0.0.1:52720/FaxQR7KmzDc=/ws
Debug service listening on ws://127.0.0.1:52720/FaxQR7KmzDc=/ws
Error: Expected a value of type 'String', but got one of type 'Null'
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 294:3       throw_
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 127:3       castError
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 818:12  cast
dart-sdk/lib/_internal/js_dev_runtime/patch/core_patch.dart 674:17                as
dart-sdk/lib/_internal/js_shared/lib/js_util_patch.dart 81:5                      getProperty
packages/firebase_core_web/firebase_core_web.dart 35:26                           _createFromJsOptions
packages/firebase_core_web/firebase_core_web.dart 27:39                           _createFromJsApp
packages/firebase_core_web/src/firebase_core_web.dart 322:12                      initializeApp
dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 45:50                <fn>
dart-sdk/lib/async/zone.dart 1661:54                                              runUnary
dart-sdk/lib/async/future_impl.dart 162:18                                        handleValue
dart-sdk/lib/async/future_impl.dart 846:44                                        handleValueCallback
dart-sdk/lib/async/future_impl.dart 875:13                                        _propagateToListeners
dart-sdk/lib/async/future_impl.dart 647:5                                         [_completeWithValue]
dart-sdk/lib/async/future.dart 529:22                                             <fn>
dart-sdk/lib/async/zone.dart 1661:54                                              runUnary
dart-sdk/lib/async/future_impl.dart 162:18                                        handleValue
dart-sdk/lib/async/future_impl.dart 846:44                                        handleValueCallback
dart-sdk/lib/async/future_impl.dart 875:13                                        _propagateToListeners
dart-sdk/lib/async/future_impl.dart 464:9                                         callback
dart-sdk/lib/async/schedule_microtask.dart 40:11                                  _microtaskLoop
dart-sdk/lib/async/schedule_microtask.dart 49:5                                   _startMicrotaskLoop
dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 181:7                <fn>

Flutter doctor

[✓] Flutter (Channel stable, 3.16.9, on macOS 13.6.1 22G313 darwin-arm64, locale en-KR)
    • Flutter version 3.16.9 on channel stable at /Users/patrick386/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 41456452f2 (6 days ago), 2024-01-25 10:06:23 -0800
    • Engine revision f40e976bed
    • Dart version 3.2.6
    • DevTools version 2.28.5

[✓] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
    • Android SDK at /Users/patrick386/Library/Android/sdk
    • Platform android-34, build-tools 34.0.0
    • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b829.9-10027231)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 14.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14C18
    • CocoaPods version 1.12.1

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2022.3)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b829.9-10027231)

[✓] IntelliJ IDEA Ultimate Edition (version 2023.2.5)
    • IntelliJ at /Applications/IntelliJ IDEA.app
    • Flutter plugin version 77.1.3
    • Dart plugin version 232.10286

[✓] VS Code (version 1.75.1)
    • VS Code at /Users/patrick386/Visual Studio Code.app/Contents
    • Flutter extension version 3.70.0

[✓] VS Code (version 1.71.1)
    • VS Code at /Users/patrick386/Downloads/Visual Studio Code.app/Contents
    • Flutter extension version 3.70.0

[✓] Connected device (3 available)
    • iPhone X (mobile) • 45C8ED4F-3398-4DD0-99DB-6A62EFE80F20 • ios            • com.apple.CoreSimulator.SimRuntime.iOS-16-2 (simulator)
    • macOS (desktop)   • macos                                • darwin-arm64   • macOS 13.6.1 22G313 darwin-arm64
    • Chrome (web)      • chrome                               • web-javascript • Google Chrome 121.0.6167.85
    ! Error: Failed to prepare the device for development. Please unlock and reconnect the device. (code 806)

[✓] Network resources
    • All expected network resources are available.

[supratim1609]

It seems like you might have missed a value in the initialization of firebase to your app, check your initialize.app function once

[Patrick386]

It seems like you might have missed a value in the initialization of firebase to your app, check your initialize.app function once

This app was working fine until the upgrade. I haven't made any changes related to initialization, and all values are properly set. Thank you.

[yarmel]

I just upgraded dependencies and encountered the same errors. Any ideas on how to fix this?

[i] [Firebase] api & services initialization
Error: Expected a value of type 'String', but got one of type 'Null'
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 294:3       throw_
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 127:3       castError
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 818:12  cast
dart-sdk/lib/_internal/js_dev_runtime/patch/core_patch.dart 674:17                as
dart-sdk/lib/_internal/js_shared/lib/js_util_patch.dart 81:5                      getProperty
packages/firebase_core_web/firebase_core_web.dart 35:26                           _createFromJsOptions
packages/firebase_core_web/firebase_core_web.dart 27:39                           _createFromJsApp
packages/firebase_core_web/src/firebase_core_web.dart 322:12                      initializeApp
dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 45:50                <fn>
dart-sdk/lib/async/zone.dart 1661:54                                              runUnary
dart-sdk/lib/async/future_impl.dart 162:18                                        handleValue
dart-sdk/lib/async/future_impl.dart 846:44                                        handleValueCallback
dart-sdk/lib/async/future_impl.dart 875:13                                        _propagateToListeners
dart-sdk/lib/async/future_impl.dart 647:5                                         [_completeWithValue]
dart-sdk/lib/async/future.dart 529:22                                             <fn>
dart-sdk/lib/async/zone.dart 1661:54                                              runUnary
dart-sdk/lib/async/future_impl.dart 162:18                                        handleValue
dart-sdk/lib/async/future_impl.dart 846:44                                        handleValueCallback
dart-sdk/lib/async/future_impl.dart 875:13                                        _propagateToListeners
dart-sdk/lib/async/future_impl.dart 464:9                                         callback
dart-sdk/lib/async/schedule_microtask.dart 40:11                                  _microtaskLoop
dart-sdk/lib/async/schedule_microtask.dart 49:5                                   _startMicrotaskLoop
dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 181:7                <fn>

[Lyokone]

Thanks for reporting I'm having a look

[ifuterman]

I have the same issue on the web. I tried to downgrade the Flutter version - this not helped

[FedeRotoli]

I have the same issue

[Spitzbua]

+1

[walsha2]

Workaround

The issue is attributed to something in firebase_core_web 2.11.0. Likely the js_interop migration. It looks like this is already being addressed in #12239

FEAT(firestore,web): migrate web to js_interop to be compatible with WASM ([#12169](https://github.com/firebase/flutterfire/issues/12169)). ([57ebd529](https://github.com/firebase/flutterfire/commit/57ebd529de5def2bab1557a1bd9967ee4267c08a))
FEAT(auth,web): migrate web to js_interop to be compatible with WASM ([#12145](https://github.com/firebase/flutterfire/issues/12145)). ([8d2df7a1](https://github.com/firebase/flutterfire/commit/8d2df7a1b2198797e9c95c45efaf21b4e5bfe766))
FEAT(core,web): migrate web to js_interop to be compatible with WASM ([#12031](https://github.com/firebase/flutterfire/issues/12031)). ([96f79d21](https://github.com/firebase/flutterfire/commit/96f79d21f51712769f33a601e4564b90d4a60a33))

In the meantime, here is a workaround solution until this gets resolved. You need to explicitly pin firebase_core_web via a dependency override to the previous version.

pubspec.yaml

dependency_overrides:
  firebase_core_web: 2.10.0

[ifuterman]

Workaround

The issue looks to be attributed to something in the firebase_core_web 2.11.0. Likely the js_interop migration. It looks like this is already being addressed in #12239

FEAT(firestore,web): migrate web to js_interop to be compatible with WASM ([#12169](https://github.com/firebase/flutterfire/issues/12169)). ([57ebd529](https://github.com/firebase/flutterfire/commit/57ebd529de5def2bab1557a1bd9967ee4267c08a))
FEAT(auth,web): migrate web to js_interop to be compatible with WASM ([#12145](https://github.com/firebase/flutterfire/issues/12145)). ([8d2df7a1](https://github.com/firebase/flutterfire/commit/8d2df7a1b2198797e9c95c45efaf21b4e5bfe766))
FEAT(core,web): migrate web to js_interop to be compatible with WASM ([#12031](https://github.com/firebase/flutterfire/issues/12031)). ([96f79d21](https://github.com/firebase/flutterfire/commit/96f79d21f51712769f33a601e4564b90d4a60a33))

In the meantime, here is a workaround solution until this gets resolved. You need to explicitly pin firebase_core_web via a dependency override.

pubspec.yaml

dependency_overrides:
  firebase_core_web: 2.10.0

It works for me!!!

[wantroba]

Same here