Add README

README.md

@@ -0,0 +1,76 @@
+# Products API
+
+Tugas Web Service Lab 03: Contract-First API Design.
+
+## Struktur Project
+
+```
+.
+├── openapi.yaml      # Kontrak API (OpenAPI 3.0.3)
+├── app.py            # Backend Flask
+├── requirements.txt  # Dependencies
+└── .env.example     # Template DATABASE_URL
+```
+
+## Setup
+
+1. Install dependencies:
+   ```
+   pip install -r requirements.txt
+   ```
+
+2. Buat file `.env`:
+   ```
+   copy .env.example .env
+   ```
+
+3. Isi `.env` dengan connection string Neon:
+   ```
+   DATABASE_URL=postgresql://user:pass@host/neondb?sslmode=require
+   ```
+
+## Jalankan Backend
+
+```
+python -m flask --app app --env-file .env run
+```
+
+Server berjalan di `http://localhost:5000`.
+
+## Endpoint
+
+| Method | Path                  | Fungsi              |
+|--------|-----------------------|---------------------|
+| GET    | /products             | Ambil semua produk  |
+| GET    | /products/{id}        | Ambil satu produk   |
+| POST   | /products             | Tambah produk baru  |
+| DELETE | /products/{id}        | Hapus produk        |
+
+## Test dengan curl
+
+```bash
+# Ambil semua produk
+curl http://localhost:5000/products
+
+# Ambil satu produk
+curl http://localhost:5000/products/1
+
+# Tambah produk baru
+curl -X POST http://localhost:5000/products \
+  -H "Content-Type: application/json" \
+  -d '{"name":"Monitor","price":1500000,"stock":5}'
+
+# Hapus produk
+curl -X DELETE http://localhost:5000/products/4
+```
+
+## Database
+
+Menggunakan PostgreSQL Neon. Tabel `products` sudah tersedia dengan struktur:
+
+| Field  | Tipe         |
+|--------|--------------|
+| id     | integer (PK) |
+| name   | varchar(100) |
+| price  | numeric(12,2)|
+| stock  | integer      |