Implement suppressor reactivation on certificate renewal
epic-certificate-expiry-notifications-orchestration-services-task-008 — Extend the mentor visibility suppressor to support reactivation: when a previously suppressed mentor's certificate is renewed and detected by the repository, restore their public listing visibility. Ensure reactivation is atomic and logs the reinstatement event with timestamp, certificate ID, and acting user for coordinator audit trail.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 2 - 518 tasks
Can start after Tier 1 completes
Implementation Notes
Add a reactivate(String mentorId, String certificateId, String actingUserId) method to the existing MentorVisibilitySuppressor class from task-007 — do not create a separate class. This keeps deactivation and reactivation logic co-located and shares the same repository dependency. For atomicity, prefer a Supabase RPC (PostgreSQL function) that performs the SELECT-then-UPDATE in a single transaction, especially to prevent a race condition where two coordinators attempt concurrent reactivation of the same mentor. The RPC should return the previous and new states so the Dart layer can construct the audit log without a second query.
If RPC is not feasible, use an optimistic update with a match filter on suppression_reason='certificate_lapsed' and check affected rows count — if 0 rows updated, the suppression_reason had changed. Clear previous_status and suppression_reason columns by setting them to NULL on reactivation, not empty string.
Testing Requirements
Unit tests (flutter_test): mock Supabase client responses for all branches — successful reactivation, suppression_reason mismatch (returns error), mentor not suppressed (returns not_suppressed), audit write failure (visibility update preserved, error logged). Integration test: seed a mentor with listing_status='deactivated', suppression_reason='certificate_lapsed', previous_status='active'; run reactivate; assert listing_status='active', suppression_reason=null, previous_status=null, audit row present. Second integration test: same seed but suppression_reason='admin_suspended'; assert reactivation rejected and row unchanged. Coverage target: 85%.
If the daily edge function runs more than once in a 24-hour window due to a Supabase scheduling anomaly or manual re-trigger, the orchestrator could dispatch duplicate push notifications to the same mentor and coordinator for the same threshold, eroding user trust.
Mitigation & Contingency
Mitigation: Implement idempotency at the notification record level using a unique constraint on (mentor_id, threshold_days, certification_id). The orchestrator checks for an existing record before dispatching. Use a database-level upsert with ON CONFLICT DO NOTHING.
Contingency: If duplicate notifications are reported in production, add a rate-limiting guard in the edge function that aborts if a notification for the same mentor and threshold was created within the last 20 hours, and add an alerting rule to Supabase logs for duplicate dispatch attempts.
The mentor visibility suppressor relies on the daily edge function to detect expiry and update suppression_status. A mentor whose certificate expires at midnight may remain visible for up to 24 hours if the cron runs at a fixed time, violating HLF's requirement that expired mentors disappear promptly.
Mitigation & Contingency
Mitigation: Schedule the edge function to run at 00:05 UTC to minimise lag after midnight transitions. Additionally, the RLS policy can include a direct date comparison (certification_expiry_date < now()) as a secondary predicate that does not rely on suppression_status, providing real-time enforcement at the database level.
Contingency: If the cron lag is unacceptable after launch, implement a Supabase database trigger on the certifications table that fires on UPDATE of expiry_date and calls the suppressor immediately, reducing lag to near-zero for renewal and expiry events.
The orchestrator needs to resolve the coordinator assigned to a specific peer mentor to dispatch coordinator-side notifications. If the assignment relationship is not normalised or is missing for some mentors, coordinator notifications will silently fail.
Mitigation & Contingency
Mitigation: Query the coordinator assignment from the existing assignments or user_roles table before dispatch. Log a structured warning (missing_coordinator_assignment: mentor_id) when no coordinator is found. Add a data quality check in the edge function that reports mentors without coordinators.
Contingency: If coordinator assignments are missing at scale, fall back to notifying the chapter-level admin role for the mentor's chapter, and surface a data quality report to the admin dashboard showing mentors without assigned coordinators.
The course enrollment prompt service generates deep-link URLs targeting the course administration feature. If the course administration feature changes its deep-link schema or the Dynamics portal URL structure changes, enrollment prompts will navigate to broken destinations.
Mitigation & Contingency
Mitigation: Define the deep-link contract between the certificate expiry feature and the course administration feature as a shared constant in a cross-feature navigation config. Version the deep-link schema and validate the generated URL format in unit tests.
Contingency: If the deep-link breaks in production, the course enrollment prompt service should gracefully fall back to opening the course administration feature root screen with a query parameter indicating the notification context, allowing the user to manually locate the correct course.