搭建Eureka服务

搭建EurekaServer

        <dependency>
            <!--eureka服务器-->
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>

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

server:
  port: 10086 # 服务端口
spring:
  application:
    name: eurekaServer   # 服务名称
eureka:
  client:
    service-url:    # eureka的地址信息，eureka自己也是一个微服务，eureka在启动的时候，会将自己也注册到eureka上，为了eureka做集群使用
      defaultZone: http://127.0.0.1:10086/eureka

注册user-service

 <!--    引入eureka客户端依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

注册多个实例

在order-service中完成服务拉取和负载均衡

package cn.itcast.order.service;

import cn.itcast.order.mapper.OrderMapper;
import cn.itcast.order.pojo.Order;
import cn.itcast.order.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

@Service
public class OrderService {

    @Autowired
    private OrderMapper orderMapper;

    @Autowired
    private RestTemplate restTemplate;

    public Order queryOrderById(Long orderId) {
        // 1.查询订单
        Order order = orderMapper.findById(orderId);
        // 2. 利用RestTemplate发起http请求，查询用户
        // 2.1 url路径
        String url = "http://userServer/user/" + order.getUserId();
        // 2.2 发送http请求，实现远程调用
        User user = restTemplate.getForObject(url, User.class);
        // 3. 封装user到Order
        order.setUser(user);
        // 4.返回
        return order;
    }
} 

@MapperScan("cn.itcast.order.mapper")
@SpringBootApplication
public class OrderApplication {

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

    /**
     * 完成创建RestTemplate，并注入容器
     * @return
     */
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }

}

总结