Notification Microservice

Build a Fastify microservice that manages user notifications. The service will be deployed in a Docker container behind an API gateway.

Endpoints

• POST /api/notifications -- Create a notification. Accepts userId (string), type ("email", "sms", "push"), title (string), message (string), and optional metadata (object).
• GET /api/notifications/:userId -- List notifications for a user. Accepts optional query params read (boolean) and limit (integer, default 20).
• PATCH /api/notifications/:id/read -- Mark a notification as read.
• DELETE /api/notifications/:id -- Delete a notification.
• GET /api/health -- Health check endpoint returning { status: "ok" }.

Use an in-memory store. Each notification gets an id, createdAt timestamp, and read: false by default.

Output

Produce TypeScript files in a src/ directory:

• src/app.ts -- Fastify app setup and plugin registration
• src/plugins/notifications.ts -- Notification routes
• src/plugins/health.ts -- Health check route
• src/services/notificationService.ts -- Notification business logic
• src/server.ts -- Server startup and configuration

Do not include test files or build configuration.