Integrate BiometricAuthService with auth repository
epic-biometric-session-authentication-core-services-task-007 — Wire BiometricAuthService into the existing auth repository layer so that successful biometric authentication updates the shared auth state. Ensures the authenticated user identity is persisted in the auth repository after biometric verification, enabling downstream role-based access checks to function correctly without requiring credential re-entry.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 6 - 158 tasks
Can start after Tier 5 completes
Implementation Notes
Define an AuthRepository.onBiometricAuthSuccess(Session session) method (or similar named contract) that accepts the refreshed session from BiometricAuthService. This keeps the repository as the single source of truth for auth state rather than having BiometricAuthService write to Supabase client directly. Use Riverpod's StateNotifier or a BehaviorSubject stream in AuthRepository to propagate auth state changes reactively to all subscribers. Ensure the existing role-based guard widgets (which presumably listen to AuthRepository) do not need modification — only the repository's internal update path changes.
After wiring, audit all downstream consumers of AuthRepository.currentUser to confirm they react correctly to biometric-sourced sessions.
Testing Requirements
Integration tests covering: biometric success updates AuthRepository.currentUser with correct User object, auth state stream emits authenticated after biometric success, role guard on a protected route passes after biometric auth, sign-out after biometric session clears all auth state. Unit test that BiometricAuthService failure paths do NOT modify AuthRepository state. Mock AuthRepository in BiometricAuthService unit tests to verify the correct method is called on success.
Multiple concurrent callers (e.g., SessionResumeManager and a background sync service) could simultaneously detect a near-expired token and each invoke SupabaseSessionManager.refreshSession(), causing duplicate refresh API calls and potentially a token invalidation race condition on the Supabase Auth server. This can result in one caller receiving a valid refreshed token while another receives a 401, causing intermittent authentication failures.
Mitigation & Contingency
Mitigation: Implement a single-flight pattern inside SupabaseSessionManager so that concurrent refresh calls coalesce into one in-flight request. Use a Dart Completer or AsyncMemoizer to ensure all waiters receive the same refreshed token. Write a concurrent integration test to validate the single-flight behaviour.
Contingency: If the single-flight pattern introduces deadlocks or timeout complexity, fall back to a mutex-based lock with a 10-second timeout, logging a warning if the lock is held longer than expected, and triggering a full re-login if the refresh ultimately fails.
Supabase Row-Level Security policies evaluate the JWT claims (user_id, role, org_id) on every query. If the refreshed token contains stale or changed claims — for example if a coordinator's role was updated server-side — RLS may silently block data access even though the session appears valid from the client's perspective, causing confusing empty screens rather than an authentication error.
Mitigation & Contingency
Mitigation: After every token refresh, decode the new JWT and compare key claims (role, org_id) with the cached values. If claims have changed, emit a session-claims-changed event that triggers a role re-resolution and navigation reset. Document this behaviour in the SupabaseSessionManager API contract.
Contingency: If claims drift is detected in production and causes data visibility issues, provide a force-refresh mechanism in the UI (pull-to-refresh on home screen) that clears cached role state and re-fetches from Supabase, accompanied by a user-visible toast indicating the session was refreshed.
Allowing session resumption from cached local token when offline introduces a window where a revoked or invalidated session can still grant app access. For example, if a coordinator deactivates a peer mentor's account while the mentor is offline, the mentor continues to have access until connectivity is restored and the token is validated server-side.
Mitigation & Contingency
Mitigation: Set a maximum offline grace period (e.g., 24 hours) stored alongside the token in SecureSessionStorage. If the grace period is exceeded, force a full credential re-login regardless of connectivity status. Scope offline access to read-only operations only, requiring connectivity for any write that reaches Supabase.
Contingency: If the offline grace period logic is found to be insufficient for compliance, implement remote session invalidation via a lightweight push notification that clears SecureSessionStorage even when the app is backgrounded, using FCM with a data-only message.