Appcheck Resource not found: oauthClients/(null) #15430
Description
Description
When using Google Sign-In with Firebase App Check debug provider, the SDK fails to pass the OAuth client ID when requesting an App Check token, resulting in oauthClients/(null) in the API request URL and a 404 error.
The app correctly configures the client ID (80866*REDECATED*.apps.googleusercontent.com) and it appears in logs, but when Google Sign-In SDK attempts to retrieve an App Check token for the OAuth flow, it sends (null) instead of the actual client ID or api key.
Expected behavior
The Google Sign-In SDK should pass the OAuth client ID when calling:
https://firebaseappcheck.googleapis.com/v1/oauthClients/{clientID}:exchangeDebugToken Instead, it sends:
https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken Actual behavior
[Google Sign-In iOS]: Error retrieving App Check limited use token: Error Domain=com.google.app_check_core Code=0 "The server responded with an error: - URL: https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken - HTTP status code: 404 - Response body: { "error": { "code": 404, "message": "com.google.apps.framework.request.NotFoundException: Resource not found: oauthClients/(null)", "status": "NOT_FOUND" } } ### Reproducing the issue Steps to reproduce: Set up a Firebase project with multiple iOS apps Configure Google Sign-In with Firebase App Check using debug provider: swift#if DEBUG GIDSignIn.sharedInstance.configureDebugProvider(withAPIKey: apiKey) { error in if let error { print("Error configuring GIDSignIn for App Check: \(error)") } } #endif Implement Google Sign-In: swift@MainActor func signInWGoogleAsync() async throws { guard let clientID = FirebaseApp.app()?.options.clientID else { return } print("Client ID: \(clientID)") // Prints correctly: 8086*REDACTED*.apps.googleusercontent.com let signInHelper = SignInWithGoogleHelper(GIDClientID: clientID) let result = try await signInHelper.signIn() let credential = GoogleAuthProvider.credential( withIDToken: result.idToken, accessToken: result.accessToken ) let authResult = try await Auth.auth().signIn(with: credential) } - Enable App Check enforcement for the OAuth client in Google Cloud Console
- Attempt to sign in with Google
- Observe the error in console logs
Environment
Firebase SDK Version: 12.4.0
Google Sign-In SDK Version: 8.0.0
Xcode Version: 16
iOS Version: 18.1
Installation Method: Swift Package Manager
Device: iPhone 18,2 (physical device)
Firebase Products:
- App Check
- Authentication
- Firestore
- Cloud Storage
Platform: iOS
Project Configuration:
- Multiple iOS apps in single Firebase project (TailoredConnect + sastrer)
- OAuth client linked to TailoredConnect app
- App Check enforcement enabled for OAuth client
- Bundle ID:
com.tailoredTechnologiesllc.TailoredConnect - Team ID: CB6LLMVDFJ
Relevant Log Output
DEBUG: App Check debug token (UUID format): D270AADC-REDACTED App Check configured with debug provider GIDSignIn configured with client ID: 8086*REDACTED*.apps.googleusercontent.com this is the clinet id when login in 8086*REDACTED*.apps.googleusercontent.com 12.4.0 - [FirebasePerformance][I-PRF100009] Logging network request trace - https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken, Response code: 404, 190.2620ms <Debug> [AppCheckCore][I-GAC004004] Failed to exchange debug token to app check token: Error Domain=com.google.app_check_core Code=0 "The server responded with an error: - URL: https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken - HTTP status code: 404 - Response body: { "error": { "code": 404, "message": "com.google.apps.framework.request.NotFoundException: Resource not found: oauthClients/(null)", "status": "NOT_FOUND" } } [Google Sign-In iOS]: Error retrieving App Check limited use token: Error Domain=com.google.app_check_core Code=0 "The server responded with an error: - URL: https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken - HTTP status code: 404 ### Firebase SDK Version 12.4 ### Xcode Version Version 26.0.1 (17A400) ### Installation Method Swift Package Manager ### Firebase Product(s) App Check, Authentication, Crashlytics, Database, Firestore, In-App Messaging, Installations, Remote Config, Storage, Analytics ### Targeted Platforms iOS ### Relevant Log Output ```shell 12.4.0 - [FirebasePerformance][I-PRF100009] Logging network request trace - https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken, Response code: 404, 190.2620ms [AppCheckCore][I-GAC004004] Failed to exchange debug token to app check token: Error Domain=com.google.app_check_core Code=0 "The server responded with an error: URL: https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken HTTP status code: 404 Response body: { "error": { "code": 404, "message": "com.google.apps.framework.request.NotFoundException: Resource not found: oauthClients/(null)", "status": "NOT_FOUND" } } [Google Sign-In iOS]: Error retrieving App Check limited use token: Error Domain=com.google.app_check_core Code=0 "The server responded with an error: URL: https://firebaseappcheck.googleapis.com/v1/oauthClients/(null):exchangeDebugToken HTTP status code: 404 If using Swift Package Manager, the project's Package.resolved
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