服务发现

服务发现：可以使用工具类根据服务名称获取对应的服务地址列表。

实现步骤

1. 添加依赖

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

2. 在主类中添加注解,开启Eureka客户端功能

@EnableDiscoveryClient

3. 配置application.yml文件

server:
  port: 8080

spring:
  application: #应用名
    name: consumer

eureka:
  client:
    service-url:
#      eureka地址
      defaultZone: http://127.0.0.1:10086/eureka

4)编写controller类（这里要注意DiscoveryClient的包，有两个相似的，容易导错，应该是import org.springframework.cloud.client.discovery.DiscoveryClient;）

package com.consumer.consumertest.controller;

import com.consumer.consumertest.pojo.User;
import com.netflix.appinfo.InstanceInfo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import java.util.List;

@RestController
@RequestMapping("/con")
public class ConsumerCon {

    @Autowired
    RestTemplate restTemplate;

    @Autowired
    DiscoveryClient discoveryClient;

    @GetMapping("/{id}")
    public User tt(@PathVariable int id) {
        String url = "http://localhost:9091/user/" + id;

//        获取eureka中注册的user-service实例列表
        List<ServiceInstance> serviceInstancesList = discoveryClient.getInstances("user-service");
        ServiceInstance serviceInstance = serviceInstancesList.get(0);

//        动态生成url
        url = "http://" + serviceInstance.getHost() + ":" + serviceInstance.getPort() + "/user/" + id;


        return restTemplate.getForObject(url, User.class);
    }


}