---
phase: 03-api-layer
plan: 01
subsystem: api
tags: [express, firebase-auth, typescript, postgres, admin-routes]

# Dependency graph
requires:
  - phase: 02-backend-services
    provides: HealthCheckModel.findLatestByService, AlertEventModel.findActive/acknowledge, document_processing_events table
  - phase: 01-data-foundation
    provides: service_health_checks, alert_events, document_processing_events tables and models
provides:
  - requireAdminEmail middleware (404 for non-admin, next() for admin)
  - getAnalyticsSummary() aggregate query function with configurable time range
  - GET /admin/health — latest health check for all four monitored services
  - GET /admin/analytics — processing summary with uploads/success/failure/avg-time
  - GET /admin/alerts — active alert events
  - POST /admin/alerts/:id/acknowledge — mark alert acknowledged
affects:
  - 04-frontend: consumes all four admin endpoints for admin dashboard

# Tech tracking
tech-stack:
  added: []
  patterns:
    - Admin routes use router-level middleware chain (addCorrelationId + verifyFirebaseToken + requireAdminEmail)
    - requireAdminEmail reads env vars inside function body (Firebase Secrets timing)
    - Fail-closed pattern: if no admin email configured, deny all with logged warning
    - getPostgresPool() for aggregate SQL (Supabase JS client does not support COUNT/AVG)
    - PostgreSQL parameterized interval with $1::interval explicit cast
    - Response envelope { success, data, correlationId } on all admin endpoints

key-files:
  created:
    - backend/src/middleware/requireAdmin.ts
    - backend/src/routes/admin.ts
  modified:
    - backend/src/services/analyticsService.ts
    - backend/src/index.ts

key-decisions:
  - "requireAdminEmail returns 404 (not 403) for non-admin users — does not reveal admin routes exist"
  - "Env vars read inside function body, not module level — Firebase Secrets not available at module load time"
  - "getPostgresPool() used for aggregate SQL (COUNT/AVG) — Supabase JS client does not support these operations"
  - "Service names in health endpoint hardcoded to match healthProbeService: document_ai, llm_api, supabase, firebase_auth"

patterns-established:
  - "Admin auth chain: addCorrelationId → verifyFirebaseToken → requireAdminEmail (router-level, applied once)"
  - "Admin 404 pattern: non-admin users and unconfigured admin get 404 to obscure admin surface"

requirements-completed: [INFR-02, HLTH-01, ANLY-02]

# Metrics
duration: 8min
completed: 2026-02-24
---

# Phase 3 Plan 01: Admin API Endpoints Summary

**Four Firebase-auth-protected admin endpoints exposing health status, alert management, and processing analytics via requireAdminEmail middleware returning 404 for non-admin**

## Performance

- **Duration:** 8 min
- **Started:** 2026-02-24T05:03:00Z
- **Completed:** 2026-02-24T05:11:00Z
- **Tasks:** 2
- **Files modified:** 4

## Accomplishments
- requireAdminEmail middleware correctly fails closed (404) for non-admin users and unconfigured environments
- getAnalyticsSummary() uses getPostgresPool() for aggregate SQL with parameterized interval cast
- All four admin endpoints mounted at /admin with router-level auth chain
- TypeScript compiles without errors across the entire backend

## Task Commits

Each task was committed atomically:

1. **Task 1: Create requireAdmin middleware and getAnalyticsSummary function** - `301d0bf` (feat)
2. **Task 2: Create admin routes and mount in Express app** - `4169a37` (feat)

**Plan metadata:** (docs commit pending)

## Files Created/Modified
- `backend/src/middleware/requireAdmin.ts` - Admin email check middleware returning 404 for non-admin
- `backend/src/routes/admin.ts` - Admin router with health, analytics, alerts endpoints (4 handlers)
- `backend/src/services/analyticsService.ts` - Added AnalyticsSummary interface and getAnalyticsSummary()
- `backend/src/index.ts` - Added adminRoutes import and app.use('/admin', adminRoutes) mount

## Decisions Made
- requireAdminEmail returns 404 (not 403) — per locked decision, do not reveal admin routes exist
- Env vars read inside function body, not at module level — Firebase Secrets timing constraint (matches alertService.ts pattern)
- getPostgresPool() for aggregate SQL because Supabase JS client does not support COUNT/AVG filters
- Service names ['document_ai', 'llm_api', 'supabase', 'firebase_auth'] hardcoded to match healthProbeService output exactly

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered
None.

## User Setup Required
None - no external service configuration required.

## Next Phase Readiness
- All four admin endpoints are ready for Phase 4 (frontend) consumption
- Admin dashboard can call GET /admin/health, GET /admin/analytics, GET /admin/alerts, POST /admin/alerts/:id/acknowledge
- No blockers — TypeScript clean, response envelopes consistent with codebase patterns

---
*Phase: 03-api-layer*
*Completed: 2026-02-24*