@SpringBootApplication
@EnableEurekaServer
public class EurekaServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(EurekaServerApplication.class, args);
    }
}

server:
  port: 8761

eureka:
  instance:
    hostname: localhost
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/

@SpringBootApplication
@EnableEurekaClient
public class UserServiceApplication {
    public static void main(String[] args) {
        SpringApplication.run(UserServiceApplication.class, args);
    }
}

spring:
  application:
    name: user-service

eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

@SpringBootApplication
@EnableConfigServer
public class ConfigServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConfigServerApplication.class, args);
    }
}

server:
  port: 8888

spring:
  cloud:
    config:
      server:
        git:
          uri: https://github.com/example/config-repo
          search-paths: '{application}'

spring:
  application:
    name: user-service
  cloud:
    config:
      uri: http://localhost:8888
      name: user-service
      profile: dev

@SpringBootApplication
public class GatewayApplication {
    public static void main(String[] args) {
        SpringApplication.run(GatewayApplication.class, args);
    }
}

spring:
  cloud:
    gateway:
      routes:
        - id: user-service
          uri: lb://user-service
          predicates:
            - Path=/api/users/**
          filters:
            - StripPrefix=1
        - id: order-service
          uri: lb://order-service
          predicates:
            - Path=/api/orders/**
          filters:
            - StripPrefix=1

@Configuration
public class GatewayConfig {
    @Bean
    public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
        return builder.routes()
            .route("user-service", r -> r
                .path("/api/users/**")
                .uri("lb://user-service"))
            .route("order-service", r -> r
                .path("/api/orders/**")
                .uri("lb://order-service"))
            .build();
    }
}

@Configuration
public class RestTemplateConfig {
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

@Configuration
public class WebClientConfig {
    @Bean
    @LoadBalanced
    public WebClient.Builder webClientBuilder() {
        return WebClient.builder();
    }
}

@Service
public class OrderService {
    private final RestTemplate restTemplate;

    public OrderService(@LoadBalanced RestTemplate restTemplate) {
        this.restTemplate = restTemplate;
    }

    public User getUser(Long userId) {
        return restTemplate.getForObject(
            "http://user-service/api/users/{id}",
            User.class,
            userId
        );
    }
}

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-circuitbreaker-resilience4j</artifactId>
</dependency>

resilience4j:
  circuitbreaker:
    instances:
      userService:
        registerHealthIndicator: true
        slidingWindowSize: 10
        failureRateThreshold: 50
        waitDurationInOpenState: 10000

@Service
public class OrderService {
    private final CircuitBreaker circuitBreaker;
    private final RestTemplate restTemplate;

    public OrderService(
        CircuitBreakerRegistry circuitBreakerRegistry,
        RestTemplate restTemplate
    ) {
        this.circuitBreaker = circuitBreakerRegistry.circuitBreaker("userService");
        this.restTemplate = restTemplate;
    }

    public User getUser(Long userId) {
        return circuitBreaker.executeSupplier(() ->
            restTemplate.getForObject(
                "http://user-service/api/users/{id}",
                User.class,
                userId
            )
        );
    }
}

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>

@SpringBootApplication
@EnableFeignClients
public class OrderServiceApplication {
    public static void main(String[] args) {
        SpringApplication.run(OrderServiceApplication.class, args);
    }
}

@FeignClient(name = "user-service")
public interface UserServiceClient {
    @GetMapping("/api/users/{id}")
    User getUserById(@PathVariable Long id);

    @PostMapping("/api/users")
    User createUser(@RequestBody User user);
}

@Service
public class OrderService {
    private final UserServiceClient userServiceClient;

    public OrderService(UserServiceClient userServiceClient) {
        this.userServiceClient = userServiceClient;
    }

    public Order createOrder(Long userId, Order order) {
        User user = userServiceClient.getUserById(userId);
        // 创建订单逻辑
        return order;
    }
}

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>

spring:
  sleuth:
    sampler:
      probability: 1.0

microservices/
├── eureka-server/          # 服务注册中心
├── config-server/          # 配置中心
├── gateway/                # API 网关
├── user-service/           # 用户服务
├── order-service/          # 订单服务
└── product-service/        # 商品服务

@FeignClient(name = "user-service")
public interface UserServiceClient {
    @GetMapping("/api/users/{id}")
    User getUserById(@PathVariable Long id);
}

@Service
public class OrderService {
    private final RabbitTemplate rabbitTemplate;

    public void publishOrderEvent(Order order) {
        rabbitTemplate.convertAndSend("order.exchange", "order.created", order);
    }
}

<!-- Eureka Client -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

<!-- Gateway -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>

<!-- Feign -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>

<!-- Circuit Breaker -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-circuitbreaker-resilience4j</artifactId>
</dependency>