This project demonstrates a microservices architecture using NestJS, RabbitMQ, and MongoDB. It consists of four independent services:

• Auth Service: Handles user authentication, registration, JWT token management, and user profile storage.
• Product Service: Manages a product catalog, associates products with users, and enforces authorization.
• Order Service: Handles order creation, updates, and integrates with inventory and product services.
• Inventory Service: Manages product stock, reservations, and inventory updates.

All services communicate via RabbitMQ and are containerized for independent deployment.

• User Registration/Login: Auth Service handles user creation and authentication, issues JWT tokens, and publishes user.created events.
• Token Validation: Product, Order, and Inventory Services validate JWTs by sending a message to Auth Service via RabbitMQ.
• Product Management: Product Service allows users to create, read, update, and delete products. Only the product owner can update/delete.
• Order Management: Order Service allows users to create, read, update, and delete orders. It checks inventory before creating orders and updates inventory on order changes.
• Inventory Management: Inventory Service tracks product stock, handles reservations/releases, and responds to order-service requests.
• Authorization: Product and Order Services enforce that only the owner can update or delete their resources, using user ID from validated JWT.
• Event Publishing: All services publish relevant events to RabbitMQ for integration and extensibility.

• Project Structure
• Features
• Setup & Installation
• Running the Project
• API Overview
• Inter-Service Communication
• Environment Variables
• Testing
• Folder Structure
• Contributing & Contact

.
├── auth-service/          # Authentication microservice
├── product-service/       # Product management microservice
├── order-service/         # Order management microservice
├── inventory-service/     # Inventory management microservice
├── docker-compose.yml     # Docker Compose configuration
└── README.md              # Project documentation

• Modular, scalable microservices architecture
• JWT-based authentication (access & refresh tokens)
• MongoDB with Typegoose models
• RabbitMQ for inter-service communication (events & RPC)
• Dockerized services with Docker Compose orchestration
• Swagger API documentation for all services
• Centralized configuration with .env files
• Unit tests for business logic
• Order management with inventory checks
• Inventory management with stock reservation and release

• Docker & Docker Compose
• Node.js (v16 or later, for local dev)

git clone <repository-url>
cd <repository-name>

Copy the example env files and fill in the required values:

cp auth-service/.env.example auth-service/.env
cp product-service/.env.example product-service/.env
cp order-service/env.example order-service/.env
# (create inventory-service/.env if needed, see below)

docker-compose up -d

• Auth Service: http://localhost:3000
• Product Service: http://localhost:3001
• Order Service: http://localhost:3002
• Inventory Service: http://localhost:3003
• RabbitMQ Management: http://localhost:15672 (guest/guest)
• MongoDB: mongodb://localhost:27017

Install dependencies and run each service:

# Auth Service
cd auth-service
npm install
npm run start:dev

# Product Service
cd ../product-service
npm install
npm run start:dev

# Order Service
cd ../order-service
npm install
npm run start:dev

# Inventory Service
cd ../inventory-service
npm install
npm run start:dev

Full API documentation is available via Swagger:

• Auth Service: http://localhost:3000/api
• Product Service: http://localhost:3001/api
• Order Service: http://localhost:3002/api
• Inventory Service: http://localhost:3003/api

• User Registration: Auth Service publishes user.created event to RabbitMQ.
• Token Validation: Product, Order, and Inventory Services send a message to Auth Service via RabbitMQ to validate JWT tokens.
• Product Events: Product Service publishes product.created, product.updated, and product.deleted events to RabbitMQ.
• Order Creation: Order Service checks inventory via RabbitMQ before creating an order, and publishes order.created events.
• Inventory Management: Inventory Service responds to stock check, reserve, and release requests from Order Service via RabbitMQ.

PORT=3000
JWT_ACCESS_SECRET=your_access_secret
JWT_REFRESH_SECRET=your_refresh_secret
JWT_ACCESS_EXPIRATION=3600s
JWT_REFRESH_EXPIRATION=7d
MONGODB_URI=mongodb://mongodb:27017/auth-db
RABBITMQ_URL=amqp://guest:guest@rabbitmq:5672

PORT=3001
MONGODB_URI=mongodb://mongodb:27017/product-db
RABBITMQ_URL=amqp://guest:guest@rabbitmq:5672

PORT=3002
MONGODB_URI=mongodb://mongodb:27017/order-db
RABBITMQ_URL=amqp://guest:guest@rabbitmq:5672

PORT=3003
MONGODB_URI=mongodb://mongodb:27017/inventory
RABBITMQ_URL=amqp://guest:guest@rabbitmq:5672

Run unit tests for each service:

# Auth Service
cd auth-service
npm run test

# Product Service
cd ../product-service
npm run test

# Order Service
cd ../order-service
npm run test

# Inventory Service
cd ../inventory-service
npm run test

auth-service/
  src/
    modules/
      auth/
        decorators/
        dto/
        guards/
        strategies/
      rabbitmq/
      users/
        dto/
        schemas/
    common/
    config/
  test/

product-service/
  src/
    modules/
      auth/
        guards/
      products/
        dto/
        schemas/
      rabbitmq/
    common/
    config/
  test/

order-service/
  src/
    modules/
      auth/
        guards/
        jwt.strategy.ts
      orders/
        dto/
        schemas/
        seed/
      rabbitmq/
    app.module.ts
    main.ts
  test/

inventory-service/
  src/
    modules/
      inventory/
        dto/
        schemas/
      rabbitmq/
    app.module.ts
    main.ts

Contributions, issues, and feature requests are welcome! Feel free to open an issue or submit a pull request.

Contact:

• Project Maintainer: Md. Imtiaz Hasan
• GitHub: Imtiaz-Hasan