# Phase 4: App Registry & Healthcheck

**Status:** ✅ Complete
**Parent plan:** [PLAN.md](./PLAN.md)
**Domain:** fullstack

## Objective

Build the app (service) registry with CRUD operations, the icon resolution system, healthcheck scheduler with node-cron, and status APIs. Create the app management UI.

## Tasks

- [x] Task 1: Create `src/routes/api/apps/+server.ts` — GET (list), POST (create)
- [x] Task 2: Create `src/routes/api/apps/[id]/+server.ts` — GET, PATCH, DELETE
- [x] Task 3: Create `src/routes/api/apps/[id]/status/+server.ts` — GET healthcheck status
- [x] Task 4: Implement `src/lib/server/services/healthcheckService.ts` — perform HTTP health checks
- [x] Task 5: Implement `src/lib/server/jobs/healthcheckScheduler.ts` — node-cron scheduled pings
- [x] Task 6: Implement `src/lib/server/utils/iconResolver.ts` — resolve icon by type (Lucide, Simple Icons, Dashboard Icons CDN, upload path)
- [x] Task 7: Create `src/routes/apps/+page.server.ts` — load app list
- [x] Task 8: Create `src/routes/apps/+page.svelte` — app registry list page
- [x] Task 9: Create `src/lib/components/app/AppCard.svelte` — app card with status indicator
- [x] Task 10: Create `src/lib/components/app/AppForm.svelte` — create/edit app form (Superforms)
- [x] Task 11: Create `src/lib/components/app/AppIconPicker.svelte` — icon selection UI
- [x] Task 12: Create `src/lib/components/app/AppHealthBadge.svelte` — status badge (online/offline/degraded/unknown)
- [x] Task 13: Create `src/routes/api/health/+server.ts` — app health endpoint for Docker healthcheck
- [x] Task 14: Handle custom icon uploads — file upload endpoint + static serving from `static/uploads/`

## Files to Modify/Create

- `src/routes/api/apps/+server.ts`
- `src/routes/api/apps/[id]/+server.ts`
- `src/routes/api/apps/[id]/status/+server.ts`
- `src/routes/api/health/+server.ts`
- `src/lib/server/services/healthcheckService.ts`
- `src/lib/server/jobs/healthcheckScheduler.ts`
- `src/lib/server/utils/iconResolver.ts`
- `src/routes/apps/+page.server.ts`
- `src/routes/apps/+page.svelte`
- `src/lib/components/app/AppCard.svelte`
- `src/lib/components/app/AppForm.svelte`
- `src/lib/components/app/AppIconPicker.svelte`
- `src/lib/components/app/AppHealthBadge.svelte`

## Acceptance Criteria

- Apps can be created, read, updated, deleted via API
- Healthcheck scheduler runs on configured intervals per app
- Status is correctly derived: online/offline/degraded/unknown
- Icon resolver correctly maps all icon types to renderable output
- App list page displays apps with status badges
- Docker health endpoint returns 200 when server is running

## Notes

- Healthcheck runs in-process via node-cron (no external job runner)
- Default healthcheck: HTTP HEAD to app URL, expect 200, 5s timeout, 60s interval
- Store last N status records in AppStatus for history (sparklines are post-MVP)
- Custom icon uploads go to `static/uploads/` (Docker volume mount)
- ⚠️ Big Bang: pages will be functional but minimally styled until Phase 7

## Review Checklist

- [x] All tasks completed
- [x] Code follows project conventions
- [x] No unintended side effects
- [ ] Build passes
- [ ] Tests pass (new + existing)

## Handoff to Next Phase

All 14 tasks are implemented. Key artifacts available for Phase 5:

- **API routes:** `/api/apps` (GET/POST), `/api/apps/[id]` (GET/PATCH/DELETE), `/api/apps/[id]/status` (GET), `/api/health` (GET), `/api/uploads` (POST)
- **Services:** `healthcheckService.ts` provides `checkAppHealth()` and `checkAllApps()`; `healthcheckScheduler.ts` provides `startScheduler()`/`stopScheduler()` using node-cron
- **Icon resolution:** `iconResolver.ts` maps all 4 icon types (lucide, simple, url, emoji) to renderable objects; `AppCard.svelte` renders them with CDN fallback for simple-icons
- **UI components:** `AppCard`, `AppForm` (Superforms), `AppIconPicker`, `AppHealthBadge` are ready for embedding in board widgets
- **File uploads:** `/api/uploads` validates SVG/PNG/JPG/WebP under 1MB, saves to `static/uploads/`
- **Page:** `/apps` lists all registered apps with category filtering, search, and inline create form

Phase 5 can reference apps via `appId` in widgets. The `appService.findAll()` and `appService.findById()` include latest status in responses. The healthcheck scheduler should be started from `hooks.server.ts` or a startup hook in Phase 8.