🛒 ecommerce-microservices-spring

E-commerce backend built with Java, Spring Boot and Microservices architecture.

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📐 Architecture

Client
  │
  ▼
┌─────────────────────┐
│    API Gateway       │  ← Spring Cloud Gateway (port 8080)
└─────────┬───────────┘
          │
    ┌─────┴──────┐
    ▼            ▼
┌────────┐  ┌────────┐
│Product │  │ Order  │
│Service │  │Service │
│ :8081  │  │ :8082  │
└────────┘  └────────┘
    │            │
  MySQL      SQL Server

          ◎ Eureka Server (port 8761)
          All services registered

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🧩 Services

Service	Port	Database	Description
eureka-server	8761	—	Service Discovery
api-gateway	8080	—	API Gateway & routing
product-service	8081	MySQL	Product catalog management
order-service	8082	SQL Server	Order processing

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🛠️ Tech Stack

• Java 17 + Spring Boot 4 + Spring Framework 7
• Spring Cloud Gateway — API Gateway with load balancing
• Netflix Eureka — Service Discovery
• OpenFeign — Declarative HTTP client for inter-service communication
• Resilience4j — Circuit Breaker pattern
• Flyway — Database migrations
• MySQL — Product Service database
• SQL Server — Order Service database

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🚀 Getting Started

Prerequisites

• Java 17+
• Maven
• MySQL running on port 3306
• SQL Server running on port 1433

Running the services

Start in this exact order:

# 1. Eureka Server
cd eureka-server && mvn spring-boot:run

# 2. Product Service
cd product-service && mvn spring-boot:run

# 3. Order Service
cd order-service && mvn spring-boot:run

# 4. API Gateway
cd api-gateway && mvn spring-boot:run

Eureka Dashboard

http://localhost:8761

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📡 API Endpoints

All requests go through the API Gateway at http://localhost:8080

Products

Method	Endpoint	Description
GET	/products	List all products
GET	/products/{id}	Get product by ID
POST	/products	Create product
PUT	/products/{id}	Update product
DELETE	/products/{id}	Delete product

Orders

Method	Endpoint	Description
GET	/orders	List all orders
GET	/orders/{id}	Get order by ID
POST	/orders	Create order

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🔁 Inter-service Communication

The Order Service communicates with the Product Service via Feign Client. Errors are translated into domain exceptions by a custom ErrorDecoder:

• 404 → ProductNotFoundException → returns 404 to the client
• 503 → ProductServiceUnavailableException → returns 503 to the client

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⚡ Resilience

• Circuit Breaker via Resilience4j protects inter-service calls
• Custom GlobalExceptionHandler ensures consistent error responses across all services

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🗂️ Error Response Format

{
  "error": "Produto não encontrado com o id informado",
  "status": 404,
  "timestamp": "2026-03-10T09:54:00.000"
}

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🗺️ Roadmap

• Service Discovery with Eureka
• API Gateway with Spring Cloud Gateway
• Inter-service communication with Feign Client
• Circuit Breaker with Resilience4j
• Database migrations with Flyway
• Redis caching
• Async messaging with RabbitMQ
• Docker Compose setup
• Distributed tracing with Zipkin

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Made with ❤️ by Rafael Bessa