微服务架构神器 Nacos｜注册发现、配置、治理一站式接入指南

<!-- 父工程控制版本 -->
<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-dependencies</artifactId>
            <version>2021.0.5.0</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<!-- 1. 服务注册发现 -->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

<!-- 2. 配置中心 -->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>

<!-- 3. 负载均衡（Spring Cloud 2021+必须） -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-loadbalancer</artifactId>
</dependency>

spring:
  application:
    name: demo-service # 服务名（必须）
  cloud:
    nacos:
      # 1. 服务注册发现配置
      discovery:
        server-addr: 127.0.0.1:8848 # Nacos地址
        username: nacos
        password: nacos
        namespace: dev # 命名空间ID（必填，环境隔离）
        group: DEFAULT_GROUP # 分组
        cluster-name: DEFAULT # 集群名
      # 2. 配置中心配置
      config:
        server-addr: ${spring.cloud.nacos.discovery.server-addr}
        username: ${spring.cloud.nacos.discovery.username}
        password: ${spring.cloud.nacos.discovery.password}
        namespace: ${spring.cloud.nacos.discovery.namespace}
        group: ${spring.cloud.nacos.discovery.group}
        file-extension: yaml # 配置文件格式
        # 配置Data ID格式：${服务名}.${后缀} → demo-service.yaml

@Configuration
public class RestTemplateConfig {
    @Bean
    @LoadBalanced // 开启负载均衡（基于服务名调用）
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

@RestController
public class TestController {
    @Autowired
    private RestTemplate restTemplate;

    @GetMapping("/test")
    public String test() {
        // 直接使用【服务名】调用，无需IP端口
        return restTemplate.getForObject("http://demo-service/hello", String.class);
    }
}

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

启动类加 @EnableFeignClients
Feign 接口：

@FeignClient(name = "demo-service")
public interface DemoFeign {
    @GetMapping("/hello")
    String hello();
}

spring:
  cloud:
    nacos:
      discovery:
        cluster-name: SHANGHAI # 标记集群

spring:
  cloud:
    nacos:
      discovery:
        metadata:
          version: 1.0
          env: test

app:
  name: demo
  version: 1.0.0

@RestController
@RefreshScope // 必须加：配置变更自动刷新
public class ConfigController {
    @Value("${app.name}")
    private String appName;

    @GetMapping("/config")
    public String getConfig() {
        return appName;
    }
}

spring:
  cloud:
    nacos:
      discovery:
        heart-beat-interval: 5000 # 心跳5s
        ip-delete-timeout: 30000 # 30s剔除