环境 springboot + springcloud
Nacos注册中心服务端
下载windows版或Linux版：https://nacos.io/zh-cn
目录结构：
配置文件./config/application.properties
启动文件./bin/startup.cmd：
cmd命令启动单机服务startup.cmd -m standalone
父工程依赖
<dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alibaba-dependencies</artifactId><version>2.2.6.RELEASE</version><type>pom</type><scope>import</scope>
</dependency>
Service提供者
pom.xml
<dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
application.yml
spring:application:name: userservice
spring:cloud:nacos:server-addr: http://localhost:8848
consumer消费者 (消费者也可以作为提供者身份出现)
pom.xml
<dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
application.yml
spring:application:name: orderservice
spring:cloud:nacos:server-addr: http://localhost:8848discovery:cluster-name: SZ # 集群名称
OrderApplication 配置RestTemplate的Bean加入到Spring容器中
@MapperScan("cn.xxx.order.mapper")
@SpringBootApplication
public class OrderApplication {public static void main(String[] args) {SpringApplication.run(OrderApplication.class, args);}@Bean@LoadBalanced # 负责均衡 和 做拉取服务public RestTemplate getRestTemplate() {return new RestTemplate();}
}
OrderService 利用RestTemplate调用 UserService接口
@Service
public class OrderService {@Autowiredprivate OrderMapper orderMapper;@Autowiredprivate RestTemplate restTemplate;public Order queryOrderById(Long orderId) {Order order = orderMapper.findById(orderId);// restTemplate.getForObject(请求地址, 返回值类型);String url = "http://userservice/user/" + order.getUserId(); // userservice是提供者的spring.application.nameUser user = restTemplate.getForObject(url, User.class);order.setUser(user);return order;}
}
同集群优先的负载均衡（NacosRule）：默认的ZoneAvoidanceRule并不能实现根据同集群优先来实现负载均衡。
application.xml
userservice:ribbon:NFLoadBalancerRuleClassName: com.alibaba.cloud.nacos.ribbon.NacosRule # Nacos负载均衡规则
