# Phase 4: App Registry & Healthcheck

**Status:** ⬜ Not Started
**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

- [ ] Task 1: Create `src/routes/api/apps/+server.ts` — GET (list), POST (create)
- [ ] Task 2: Create `src/routes/api/apps/[id]/+server.ts` — GET, PATCH, DELETE
- [ ] Task 3: Create `src/routes/api/apps/[id]/status/+server.ts` — GET healthcheck status
- [ ] Task 4: Implement `src/lib/server/services/healthcheckService.ts` — perform HTTP health checks
- [ ] Task 5: Implement `src/lib/server/jobs/healthcheckScheduler.ts` — node-cron scheduled pings
- [ ] Task 6: Implement `src/lib/server/utils/iconResolver.ts` — resolve icon by type (Lucide, Simple Icons, Dashboard Icons CDN, upload path)
- [ ] Task 7: Create `src/routes/apps/+page.server.ts` — load app list
- [ ] Task 8: Create `src/routes/apps/+page.svelte` — app registry list page
- [ ] Task 9: Create `src/lib/components/app/AppCard.svelte` — app card with status indicator
- [ ] Task 10: Create `src/lib/components/app/AppForm.svelte` — create/edit app form (Superforms)
- [ ] Task 11: Create `src/lib/components/app/AppIconPicker.svelte` — icon selection UI
- [ ] Task 12: Create `src/lib/components/app/AppHealthBadge.svelte` — status badge (online/offline/degraded/unknown)
- [ ] Task 13: Create `src/routes/api/health/+server.ts` — app health endpoint for Docker healthcheck
- [ ] 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
- [ ] All tasks completed
- [ ] Code follows project conventions
- [ ] No unintended side effects
- [ ] Build passes
- [ ] Tests pass (new + existing)

## Handoff to Next Phase
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