---
phase: 04-frontend
plan: 01
subsystem: ui
tags: [react, typescript, tailwind, lucide-react, axios]

# Dependency graph
requires:
  - phase: 03-api-layer
    provides: "GET /admin/health, GET /admin/analytics, GET /admin/alerts, POST /admin/alerts/:id/acknowledge endpoints"
provides:
  - "AdminService typed methods: getHealth(), getAnalytics(range), getAlerts(), acknowledgeAlert(id)"
  - "AlertEvent, ServiceHealthEntry, AnalyticsSummary TypeScript interfaces"
  - "AlertBanner component: critical active alert display with per-alert acknowledge button"
  - "AdminMonitoringDashboard component: service health grid + analytics summary with range selector"
affects:
  - 04-02 (wires AlertBanner and AdminMonitoringDashboard into App.tsx Dashboard)

# Tech tracking
tech-stack:
  added: []
  patterns:
    - "useCallback + useEffect for data fetching with re-fetch on state dependency changes"
    - "Promise.all for concurrent independent API calls"
    - "Optimistic UI: AlertBanner onAcknowledge pattern is defined at the parent level to filter local state immediately"
    - "Status dot pattern: w-3 h-3 rounded-full with Tailwind bg-color for health indicators"

key-files:
  created:
    - frontend/src/components/AlertBanner.tsx
    - frontend/src/components/AdminMonitoringDashboard.tsx
  modified:
    - frontend/src/services/adminService.ts

key-decisions:
  - "AlertBanner filters to active service_down/service_degraded only — recovery type is informational, not critical (per RESEARCH Pitfall)"
  - "AlertEvent uses snake_case fields (backend returns raw model data), ServiceHealthEntry/AnalyticsSummary use camelCase (backend admin.ts remaps)"
  - "AdminMonitoringDashboard has no required props — self-contained component that fetches its own data"

patterns-established:
  - "Monitoring dashboard pattern: health grid + analytics stat cards in same component"
  - "Alert banner pattern: top-level conditional render, filters by status=active AND critical alert_type"

requirements-completed:
  - ALRT-03
  - ANLY-02
  - HLTH-01

# Metrics
duration: 2min
completed: 2026-02-24
---

# Phase 04 Plan 01: Monitoring Service Layer and Components Summary

**AdminService extended with typed monitoring API methods plus AlertBanner and AdminMonitoringDashboard React components ready for mounting in App.tsx**

## Performance

- **Duration:** 2 min
- **Started:** 2026-02-24T21:33:40Z
- **Completed:** 2026-02-24T21:35:33Z
- **Tasks:** 2
- **Files modified:** 3

## Accomplishments

- Extended `adminService.ts` with three new exported TypeScript interfaces (AlertEvent, ServiceHealthEntry, AnalyticsSummary) and four new typed API methods (getHealth, getAnalytics, getAlerts, acknowledgeAlert)
- Created `AlertBanner` component that filters alerts to active critical types only and renders a red banner with per-alert acknowledge buttons
- Created `AdminMonitoringDashboard` component with a 1x4 service health card grid (colored status dots) and a 1x5 analytics stat card panel with range selector and refresh button

## Task Commits

Each task was committed atomically:

1. **Task 1: Extend adminService with monitoring API methods and types** - `f84a822` (feat)
2. **Task 2: Create AlertBanner and AdminMonitoringDashboard components** - `b457b9e` (feat)

## Files Created/Modified

- `frontend/src/services/adminService.ts` - Added AlertEvent, ServiceHealthEntry, AnalyticsSummary interfaces and getHealth(), getAnalytics(), getAlerts(), acknowledgeAlert() methods
- `frontend/src/components/AlertBanner.tsx` - New component rendering red banner for active service_down/service_degraded alerts with X Acknowledge buttons
- `frontend/src/components/AdminMonitoringDashboard.tsx` - New component with service health grid and processing analytics panel with range selector

## Decisions Made

- AlertBanner renders only `status === 'active'` alerts of type `service_down` or `service_degraded`; `recovery` alerts are filtered out as informational
- Type casing follows backend API response shapes exactly: AlertEvent is snake_case (raw model), ServiceHealthEntry/AnalyticsSummary are camelCase (backend admin.ts remaps them)
- AdminMonitoringDashboard is self-contained with no required props, following existing Analytics.tsx pattern

## 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 three files are ready to import in Plan 02 (App.tsx wiring)
- AlertBanner expects `alerts: AlertEvent[]` and `onAcknowledge: (id: string) => Promise<void>` — parent must manage alert state and provide optimistic acknowledge handler
- AdminMonitoringDashboard has no required props — drop-in for the monitoring tab

---
*Phase: 04-frontend*
*Completed: 2026-02-24*