🔐 Spring Microservices Security Example

⚡ Microservices Security Architecture Diagram

🐳 Docker Services

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📋 Project Overview

This project demonstrates a comprehensive Spring Boot Microservices architecture with robust security implementation using Spring Security, API Gateway, and Service Discovery. The system includes JWT-based authentication, header-based service communication, and distributed authorization.

🏗️ Architecture Components

• 🌐 API Gateway - Central entry point with routing and authentication
• 🔐 Auth Service - JWT token generation and validation
• 👥 User Service - User management and profiles
• 📋 Custom Service - Business logic with role-based access control
• 🗄️ PostgreSQL - Persistent data storage
• 🔍 Consul - Service discovery and configuration management

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🛠️ Technologies

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🚀 Quick Start

Prerequisites

• Java 17+
• Gradle 8.5+
• Docker & Docker Compose
• Git

📥 Installation

# Clone the repository
git clone https://github.com/furkankayam/spring-microservices-security-example.git
cd spring-microservices-security-example

🐳 Running with Docker

# Build Docker images
gradle jibDockerBuild

# Start all services
docker-compose up -d

# View logs
docker-compose logs -f

🏃‍♂️ Running Locally

# Start Consul (required for service discovery)
docker run -d -p 8500:8500 --name consul consul:latest

# Start PostgreSQL
docker run -d -p 5432:5432 --name postgres \
  -e POSTGRES_DB=user_db \
  -e POSTGRES_USER=postgres \
  -e POSTGRES_PASSWORD=postgres \
  postgres:15

# Run services in order
cd auth-service && ./gradlew bootRun
cd user-service && ./gradlew bootRun  
cd custom-service && ./gradlew bootRun
cd api-gateway && ./gradlew bootRun

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🔗 API Endpoints

🌍 Public Endpoints

POST   http://localhost:8080/auth/generate-token           # Generate JWT token
POST   http://localhost:8080/users/save                    # Register new user
GET    http://localhost:8080/users/{username}/profile      # Get user profile
GET    http://localhost:8080/customs/public                # Public custom endpoint

🔒 Protected Endpoints

GET    http://localhost:8080/customs/private/user          # USER role required
GET    http://localhost:8080/customs/private/admin         # ADMIN role required  
GET    http://localhost:8080/customs/private/admin-and-user # USER or ADMIN role required

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🔧 Configuration

🗄️ Database Configuration

Database URL: jdbc:postgresql://localhost:5432/user_db
Username: postgres
Password: postgres

🌐 Service Ports

API Gateway:    8080
Auth Service:   8081
User Service:   8082
Custom Service: 8083
Consul:         8500
PostgreSQL:     5432

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🧪 Testing

📝 Example API Calls

# 1. Register a new user
curl -X POST http://localhost:8080/users/save \
  -H "Content-Type: application/json" \
  -d '{"username": "testuser", "password": "password123", "role": "USER"}'

# 2. Generate JWT token
curl -X POST http://localhost:8080/auth/generate-token \
  -H "Content-Type: application/json" \
  -d '{"username": "testuser", "password": "password123"}'

# 3. Access protected endpoint
curl -X GET http://localhost:8080/customs/private/user \
  -H "Authorization: Bearer YOUR_JWT_TOKEN"

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🛡️ Security Features

• ✅ JWT Authentication - Stateless token-based auth
• ✅ Role-Based Access Control - Method-level security with @PreAuthorize
• ✅ API Gateway Integration - Centralized authentication
• ✅ Header-Based Service Communication - Secure inter-service calls
• ✅ Service Discovery - Dynamic service registration with Consul
• ✅ CORS Configuration - Cross-origin request handling

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📊 Monitoring

Health Checks

# Service health endpoints
GET http://localhost:8080/actuator/health
GET http://localhost:8081/actuator/health
GET http://localhost:8082/actuator/health
GET http://localhost:8083/actuator/health

# Consul UI
http://localhost:8500/ui

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📚 Project Structure

spring-microservices-security-example/
├── api-gateway/          # Spring Cloud Gateway
├── auth-service/         # Authentication & JWT
├── user-service/         # User management
├── custom-service/       # Business logic
├── docker-compose.yml    # Multi-service setup
└── README.md

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🤝 Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

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📄 License

This project is licensed under the MIT License. See the LICENSE file for details.

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Created with ❤️ by Mehmet Furkan KAYA