[firebase_in_app_messaging]: Android build fails with `Could not find com.google.firebase:firebase-inappmessaging:.` since 0.10.0

Is there an existing issue for this?

• I have searched the existing issues.

Which plugins are affected?

In-App Messaging

Which platforms are affected?

Android

Description

Since firebase_in_app_messaging 0.10.0, any Flutter Android app that depends on the plugin fails to build. Gradle cannot resolve the app's debugCompileClasspath because com.google.firebase:firebase-inappmessaging and com.google.firebase:firebase-inappmessaging-display are requested without a version.

Expected: flutter build apk succeeds on a freshly created app with only firebase_core and firebase_in_app_messaging added (as it does with 0.9.4).

Actual: The build fails with Could not find com.google.firebase:firebase-inappmessaging:. / Could not find com.google.firebase:firebase-inappmessaging-display:.

#18586 changed the plugin's android/build.gradle to expose the Firebase artifacts as api, while the Firebase BoM is still declared as implementation platform(...):

dependencies {
  api firebaseCoreProject
  implementation platform("com.google.firebase:firebase-bom:${getRootProjectExtOrCoreProperty("FirebaseSDKVersion", firebaseCoreProject)}")
  // `api` so app Java compilation can resolve FirebaseInAppMessagingDisplay,
  // which the plugin class implements.
  api 'com.google.firebase:firebase-inappmessaging'
  api 'com.google.firebase:firebase-inappmessaging-display'
  implementation 'androidx.annotation:annotation:1.7.0'
}

The versionless api dependencies are exported to the consuming app's compile classpath, but the BoM is an implementation dependency, so its version constraints are not. As a result, the app sees firebase-inappmessaging and firebase-inappmessaging-display with an empty version.

Results with Flutter 3.47.8 (AGP 9.1.0, Gradle 9.3.1, KGP 2.4.0):

Workaround: add the Firebase BoM to the app module:

// android/app/build.gradle.kts
dependencies {
    implementation(platform("com.google.firebase:firebase-bom:35.1.0"))
}

Reproducing the issue

1. flutter create --platforms android iam_repro
2. cd iam_repro
3. flutter pub add firebase_core firebase_in_app_messaging (resolves firebase_core 5.1.0, firebase_in_app_messaging 0.10.1)
4. flutter build apk --debug

No Dart code changes or google-services.json are needed to reproduce; the failure happens while Gradle resolves dependencies.

Firebase Core version

5.1.0

Flutter Version

3.47.8

Relevant Log Output

Running Gradle task 'assembleDebug'...
WARNING: A restricted method in java.lang.System has been called
WARNING: java.lang.System::load has been called by net.rubygrapefruit.platform.internal.NativeLibraryLoader in an unnamed module (file:/Users/koji/.gradle/wrapper/dists/gradle-9.3.1-all/9ot9r568e8zfvvd4mn8rbu1j0/gradle-9.3.1/lib/native-platform-0.22-milestone-29.jar)
WARNING: Use --enable-native-access=ALL-UNNAMED to avoid a warning for callers in this module
WARNING: Restricted methods will be blocked in a future release unless native access is enabled

WARNING: Your app uses the following plugins that apply Kotlin Gradle Plugin (KGP): firebase_core, firebase_in_app_messaging
Future versions of Flutter will fail to build if your app uses plugins that apply KGP.

Please check the changelogs of these plugins and upgrade to a version that supports Built-in Kotlin.
If no such version exists, report the issue to the plugin. If necessary, here is a guide on filing
an issue against a plugin: https://docs.flutter.dev/release/breaking-changes/migrate-to-built-in-kotlin/for-app-developers#report-incompatible-kotlin-gradle-plugin-usage-to-plugin-authors

If you are a plugin author, please migrate your plugin to Built-in Kotlin using this guide: https://docs.flutter.dev/release/breaking-changes/migrate-to-built-in-kotlin/for-plugin-authors

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:compileDebugKotlin'.
> Error while evaluating property 'friendPathsSet$kotlin_gradle_plugin_common' of task ':app:compileDebugKotlin'.
   > Could not resolve all files for configuration ':app:debugCompileClasspath'.
      > Could not find com.google.firebase:firebase-inappmessaging:.
        Required by:
            project ':app' > project :firebase_in_app_messaging
      > Could not find com.google.firebase:firebase-inappmessaging-display:.
        Required by:
            project ':app' > project :firebase_in_app_messaging

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights from a Build Scan (powered by Develocity).
> Get more help at https://help.gradle.org.

BUILD FAILED in 4s
Running Gradle task 'assembleDebug'...                              4.4s
Gradle task assembleDebug failed with exit code 1

Flutter dependencies

Dart SDK 3.13.7
Flutter SDK 3.47.8
iam_repro 1.0.0+1

dependencies:
- cupertino_icons 1.0.9
- firebase_core 5.1.0 [firebase_core_platform_interface firebase_core_web flutter meta]
- firebase_in_app_messaging 0.10.1 [firebase_core firebase_core_platform_interface firebase_in_app_messaging_platform_interface flutter meta]
- flutter 0.0.0 [characters collection material_color_utilities meta vector_math sky_engine]

dev dependencies:
- flutter_lints 6.0.0 [lints]
- flutter_test 0.0.0 [flutter test_api matcher path fake_async clock stack_trace vector_math leak_tracker_flutter_testing collection meta stream_channel]

transitive dependencies:
- _flutterfire_internals 1.3.79 [collection firebase_core firebase_core_platform_interface flutter meta]
- async 2.13.1 [collection meta]
- boolean_selector 2.1.2 [source_span string_scanner]
- characters 1.4.1
- clock 1.1.3
- collection 1.19.1
- fake_async 1.3.3 [clock collection]
- firebase_core_platform_interface 8.1.1 [collection flutter meta plugin_platform_interface]
- firebase_core_web 4.1.0 [firebase_core_platform_interface meta web]
- firebase_in_app_messaging_platform_interface 0.2.7+30 [_flutterfire_internals firebase_core flutter meta plugin_platform_interface]
- leak_tracker 11.0.2 [clock collection meta path vm_service]
- leak_tracker_flutter_testing 3.0.10 [flutter leak_tracker leak_tracker_testing matcher meta]
- leak_tracker_testing 3.0.2 [leak_tracker matcher meta]
- lints 6.1.0
- matcher 0.12.20 [async meta stack_trace term_glyph test_api]
- material_color_utilities 0.13.0 [collection]
- meta 1.18.3
- path 1.9.1
- plugin_platform_interface 2.1.8 [meta]
- sky_engine 0.0.0
- source_span 1.10.2 [collection path term_glyph]
- stack_trace 1.12.2 [path]
- stream_channel 2.1.4 [async]
- string_scanner 1.4.1 [source_span]
- term_glyph 1.2.2
- test_api 0.7.12 [async boolean_selector collection meta source_span stack_trace stream_channel string_scanner term_glyph]
- vector_math 2.4.0
- vm_service 15.4.0
- web 1.1.2

Additional context and comments

Possible fix:

• Revert firebase-inappmessaging and firebase-inappmessaging-display to implementation (as in 0.9.4), so they are not exported to the app.
• Stop having FirebaseInAppMessagingPlugin implement FirebaseInAppMessagingDisplay directly, and instead set a private property (for example, a lambda) as the display component, so the plugin class's public API no longer references Firebase In-App Messaging types and the app can compile GeneratedPluginRegistrant without them.