---
phase: 01-foundation-and-collection
plan: 02
subsystem: api
tags: [hono, drizzle, zod, sqlite, crud, tdd, image-upload]

requires:
  - phase: 01-foundation-and-collection/01
    provides: SQLite schema, shared Zod schemas, test helper, Hono server scaffold
provides:
  - Item CRUD service layer with category join
  - Category CRUD service with Uncategorized reassignment on delete
  - Computed totals (per-category and global weight/cost/count)
  - Image upload endpoint with type/size validation
  - Hono API routes with Zod request validation
  - Integration tests for all API endpoints
affects: [01-03, 01-04]

tech-stack:
  added: []
  patterns: [service-layer-di, hono-context-db-injection, tdd-red-green]

key-files:
  created:
    - src/server/services/item.service.ts
    - src/server/services/category.service.ts
    - src/server/services/totals.service.ts
    - src/server/routes/items.ts
    - src/server/routes/categories.ts
    - src/server/routes/totals.ts
    - src/server/routes/images.ts
    - tests/services/item.service.test.ts
    - tests/services/category.service.test.ts
    - tests/services/totals.test.ts
    - tests/routes/items.test.ts
    - tests/routes/categories.test.ts
  modified:
    - src/server/index.ts

key-decisions:
  - "Service functions accept db as first parameter with production default for testability"
  - "Routes use Hono context variables for DB injection enabling integration tests with in-memory SQLite"
  - "Totals computed via SQL aggregates on every read, never cached"

patterns-established:
  - "Service layer DI: all service functions take db as first param, defaulting to production db"
  - "Route testing: inject test DB via Hono context middleware, use app.request() for integration tests"
  - "Category delete safety: guard against deleting id=1, reassign items before delete"

requirements-completed: [COLL-01, COLL-02, COLL-03, COLL-04]

duration: 3min
completed: 2026-03-14
---

# Phase 1 Plan 02: Backend API Summary

**Item/category CRUD with Zod-validated Hono routes, computed totals via SQL aggregates, image upload, and 30 passing tests via TDD**

## Performance

- **Duration:** 3 min
- **Started:** 2026-03-14T21:37:37Z
- **Completed:** 2026-03-14T21:40:54Z
- **Tasks:** 2
- **Files modified:** 13

## Accomplishments

- Complete item CRUD service layer with category join queries
- Category CRUD with Uncategorized reassignment on delete (transaction-safe)
- Per-category and global weight/cost/count totals via SQL SUM/COUNT aggregates
- Hono API routes with Zod request validation for all endpoints
- Image upload endpoint with file type and size validation
- 30 tests passing (20 unit + 10 integration) built via TDD

## Task Commits

Each task was committed atomically:

1. **Task 1: Service layer with tests (RED)** - `f906779` (test)
2. **Task 1: Service layer implementation (GREEN)** - `22757a8` (feat)
3. **Task 2: API routes, image upload, integration tests** - `029adf4` (feat)

## Files Created/Modified

- `src/server/services/item.service.ts` - Item CRUD business logic with category join
- `src/server/services/category.service.ts` - Category CRUD with reassignment on delete
- `src/server/services/totals.service.ts` - Per-category and global totals aggregation
- `src/server/routes/items.ts` - Hono routes for /api/items with Zod validation
- `src/server/routes/categories.ts` - Hono routes for /api/categories with delete protection
- `src/server/routes/totals.ts` - Hono route for /api/totals
- `src/server/routes/images.ts` - Image upload with type/size validation
- `src/server/index.ts` - Registered all API routes
- `tests/services/item.service.test.ts` - 7 unit tests for item CRUD
- `tests/services/category.service.test.ts` - 7 unit tests for category CRUD
- `tests/services/totals.test.ts` - 4 unit tests for totals aggregation
- `tests/routes/items.test.ts` - 6 integration tests for item API
- `tests/routes/categories.test.ts` - 4 integration tests for category API

## Decisions Made

- Service functions accept `db` as first parameter with production default for dependency injection and testability
- Routes use Hono context variables (`c.get("db")`) for DB injection, enabling integration tests with in-memory SQLite without mocking
- Totals computed via SQL aggregates on every read per RESEARCH.md recommendation (never cached)
- `updateItemSchema.omit({ id: true })` used for PUT routes since id comes from URL params

## 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 backend API endpoints ready for frontend consumption (Plan 01-03)
- Service layer provides clean interface for TanStack Query hooks
- Test infrastructure supports both unit and integration testing patterns

## Self-Check: PASSED

All 12 created files verified present. All 3 task commits verified in git log.

---
*Phase: 01-foundation-and-collection*
*Completed: 2026-03-14*