Java Spring Boot - Microservices Patterns

Category: Software Programming & Architecture Tags: spring-boot, microservices, architecture, java, patterns

Resilience Patterns

Circuit Breaker Pattern

Prevents cascading failures in distributed systems

• States: Closed, Open, Half-Open
• Implementation: Use Hystrix or Resilience4j
• Configuration: Failure threshold, timeout, recovery time

@Component
public class UserService {
    @CircuitBreaker(name = "userService", fallbackMethod = "fallbackUser")
    public User getUser(Long id) {
        return userRepository.findById(id);
    }

    public User fallbackUser(Long id, Exception ex) {
        return new User("Unknown User");
    }
}

API Gateway Pattern

Single entry point for all clients

• Responsibilities: Authentication, routing, rate limiting, logging
• Tools: Spring Cloud Gateway, Zuul, Kong
• Benefits: Simplified client code, centralized concerns

Service Discovery

Client-side

• Netflix Eureka
• Consul

Server-side

• AWS ELB
• Kubernetes services

Health checks

• Regular service health monitoring

Saga Pattern

Manages distributed transactions

• Choreography: Each service publishes events
• Orchestration: Central coordinator manages flow
• Compensation: Rollback mechanisms for failures