跳至主要內容

Spring Cloud Consul集成

Salmon2026/1/15大约 4 分钟ConsulSpring Cloud微服务

Spring Cloud Consul 集成

一、概述

Spring Cloud Consul 提供了与 Consul 的无缝集成，支持服务发现、配置管理和分布式锁等功能。

1.1 核心功能

二、快速开始

2.1 添加依赖

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>2023.0.0</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<dependencies>
    <!-- 服务发现 -->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-consul-discovery</artifactId>
    </dependency>
    
    <!-- 配置管理 -->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-consul-config</artifactId>
    </dependency>
    
    <!-- Actuator -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
</dependencies>

2.2 基础配置

# application.yml
spring:
  application:
    name: user-service
  cloud:
    consul:
      host: localhost
      port: 8500

三、服务发现

3.1 启用服务发现

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

3.2 服务发现配置

spring:
  cloud:
    consul:
      discovery:
        enabled: true
        service-name: ${spring.application.name}
        instance-id: ${spring.application.name}:${random.value}
        prefer-ip-address: true
        ip-address: ${HOST_IP:localhost}
        port: ${server.port}
        health-check-path: /actuator/health
        health-check-interval: 10s
        tags:
          - version=1.0.0
          - env=dev
        metadata:
          zone: zone-a
          weight: 10

3.3 使用 DiscoveryClient

@RestController
public class DiscoveryController {
    
    @Autowired
    private DiscoveryClient discoveryClient;
    
    @GetMapping("/services")
    public List<String> getServices() {
        return discoveryClient.getServices();
    }
    
    @GetMapping("/instances/{serviceName}")
    public List<ServiceInstance> getInstances(@PathVariable String serviceName) {
        return discoveryClient.getInstances(serviceName);
    }
}

四、服务调用

4.1 RestTemplate + LoadBalancer

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

@Service
public class OrderService {
    
    @Autowired
    private RestTemplate restTemplate;
    
    public User getUser(Long userId) {
        return restTemplate.getForObject(
            "http://user-service/users/" + userId,
            User.class
        );
    }
}

4.2 OpenFeign 集成

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
@EnableFeignClients
@SpringBootApplication
public class OrderServiceApplication {
    public static void main(String[] args) {
        SpringApplication.run(OrderServiceApplication.class, args);
    }
}

@FeignClient(name = "user-service")
public interface UserClient {
    
    @GetMapping("/users/{id}")
    User getUser(@PathVariable("id") Long id);
    
    @PostMapping("/users")
    User createUser(@RequestBody User user);
}

@RestController
public class OrderController {
    
    @Autowired
    private UserClient userClient;
    
    @GetMapping("/orders/{id}")
    public Order getOrder(@PathVariable Long id) {
        Order order = orderRepository.findById(id);
        User user = userClient.getUser(order.getUserId());
        order.setUser(user);
        return order;
    }
}

4.3 WebClient 集成

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

@Service
public class UserService {
    
    @Autowired
    private WebClient.Builder webClientBuilder;
    
    public Mono<User> getUser(Long id) {
        return webClientBuilder.build()
            .get()
            .uri("http://user-service/users/{id}", id)
            .retrieve()
            .bodyToMono(User.class);
    }
}

五、配置管理

5.1 Bootstrap 配置

# bootstrap.yml
spring:
  application:
    name: user-service
  cloud:
    consul:
      host: localhost
      port: 8500
      config:
        enabled: true
        format: YAML
        prefix: config
        default-context: application
        profile-separator: ','
        data-key: data
        watch:
          enabled: true
          delay: 1000

5.2 在 Consul 存储配置

# 公共配置
consul kv put config/application/data '
logging:
  level:
    root: INFO
'

# 服务配置
consul kv put config/user-service/data '
server:
  port: 8080
user:
  default-role: USER
'

# 环境配置
consul kv put config/user-service,dev/data '
user:
  default-role: ADMIN
'

5.3 使用配置

@RestController
@RefreshScope
public class ConfigController {
    
    @Value("${user.default-role}")
    private String defaultRole;
    
    @GetMapping("/config/role")
    public String getDefaultRole() {
        return defaultRole;
    }
}

5.4 配置类绑定

@Configuration
@ConfigurationProperties(prefix = "user")
@RefreshScope
public class UserProperties {
    
    private String defaultRole;
    private int maxLoginAttempts;
    private Duration sessionTimeout;
    
    // getters and setters
}

六、健康检查

6.1 配置健康检查

spring:
  cloud:
    consul:
      discovery:
        health-check-path: /actuator/health
        health-check-interval: 10s
        health-check-timeout: 5s
        health-check-critical-timeout: 30s

6.2 自定义健康指示器

@Component
public class DatabaseHealthIndicator implements HealthIndicator {
    
    @Autowired
    private DataSource dataSource;
    
    @Override
    public Health health() {
        try (Connection conn = dataSource.getConnection()) {
            return Health.up()
                .withDetail("database", "connected")
                .build();
        } catch (SQLException e) {
            return Health.down()
                .withDetail("error", e.getMessage())
                .build();
        }
    }
}

七、负载均衡

7.1 Spring Cloud LoadBalancer

spring:
  cloud:
    loadbalancer:
      ribbon:
        enabled: false  # 禁用 Ribbon

7.2 自定义负载均衡策略

@Configuration
public class LoadBalancerConfig {
    
    @Bean
    public ReactorLoadBalancer<ServiceInstance> randomLoadBalancer(
            Environment environment,
            LoadBalancerClientFactory loadBalancerClientFactory) {
        String name = environment.getProperty(LoadBalancerClientFactory.PROPERTY_NAME);
        return new RandomLoadBalancer(
            loadBalancerClientFactory.getLazyProvider(name, ServiceInstanceListSupplier.class),
            name
        );
    }
}

7.3 基于权重的负载均衡

@Configuration
public class WeightedLoadBalancerConfig {
    
    @Bean
    public ServiceInstanceListSupplier weightedSupplier(
            ConfigurableApplicationContext context) {
        return ServiceInstanceListSupplier.builder()
            .withDiscoveryClient()
            .withWeighted()
            .withCaching()
            .build(context);
    }
}

八、分布式锁

8.1 使用 Consul Lock

@Service
public class DistributedLockService {
    
    @Autowired
    private ConsulClient consulClient;
    
    public void executeWithLock(String lockKey, Runnable task) {
        String sessionId = createSession(lockKey);
        
        try {
            if (acquireLock(lockKey, sessionId)) {
                task.run();
            }
        } finally {
            releaseLock(lockKey, sessionId);
            destroySession(sessionId);
        }
    }
    
    private String createSession(String name) {
        NewSession session = new NewSession();
        session.setName(name);
        session.setTtl("30s");
        return consulClient.sessionCreate(session, null).getValue();
    }
    
    private boolean acquireLock(String key, String sessionId) {
        PutParams params = new PutParams();
        params.setAcquireSession(sessionId);
        return consulClient.setKVValue("locks/" + key, "locked", params).getValue();
    }
    
    private void releaseLock(String key, String sessionId) {
        PutParams params = new PutParams();
        params.setReleaseSession(sessionId);
        consulClient.setKVValue("locks/" + key, "unlocked", params);
    }
    
    private void destroySession(String sessionId) {
        consulClient.sessionDestroy(sessionId, null);
    }
}

九、服务网格

9.1 启用 Connect

spring:
  cloud:
    consul:
      discovery:
        register: true
        connect:
          enabled: true

9.2 Sidecar 代理配置

{
  "service": {
    "name": "user-service",
    "port": 8080,
    "connect": {
      "sidecar_service": {
        "proxy": {
          "upstreams": [
            {
              "destination_name": "order-service",
              "local_bind_port": 9001
            }
          ]
        }
      }
    }
  }
}

十、生产配置

10.1 完整配置示例

spring:
  application:
    name: user-service
  profiles:
    active: ${SPRING_PROFILES_ACTIVE:dev}
  cloud:
    consul:
      host: ${CONSUL_HOST:localhost}
      port: ${CONSUL_PORT:8500}
      discovery:
        enabled: true
        service-name: ${spring.application.name}
        instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${server.port}
        prefer-ip-address: true
        health-check-path: /actuator/health
        health-check-interval: 10s
        health-check-critical-timeout: 30s
        acl-token: ${CONSUL_ACL_TOKEN:}
        tags:
          - version=${APP_VERSION:1.0.0}
          - env=${SPRING_PROFILES_ACTIVE:dev}
        metadata:
          zone: ${ZONE:default}
      config:
        enabled: true
        format: YAML
        prefix: config
        default-context: application
        profile-separator: ','
        data-key: data
        acl-token: ${CONSUL_ACL_TOKEN:}
        watch:
          enabled: true
          delay: 1000

management:
  endpoints:
    web:
      exposure:
        include: health,info,metrics
  endpoint:
    health:
      show-details: always

十一、总结

最近更新:
贡献者: Salmon