微服务feign.RetryableException: Load balancer does not contain an instance for the service解决方案

全程只有图,文字很少描述!

遇到的问题~​​feign.RetryableException: connect timed out executing POST http://xxx ........ Load balancer does not contain an instance for the service​​

依赖的版本~

<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
            <version>3.1.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
              <version>3.1.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
            <version>1.4.7.RELEASE</version>
        </dependency>

环境配置

运行环境--win10 
Ide--->>Idea 2019
springboot 2.6.6
 jdk版本 11
 测试工具 postman,用浏览器也可以

昨天搜的解决方案~说什么可能是版本的问题,这里我也没有尝试换版本,而是坚持采用最新版本;

晚上睡觉前终于想通了,画图来阐述一下

这里解析一下背后的逻辑

注意的地方----hostname那里写服务提供者的地址,不写那么就要在本机里修改host,考虑到分布式又不是部署在一个机器上,所以最好还是写;

放上部分代码以供参考~
首先是 服务提供者~

package com.gavin.repository.service.impl;

import com.gavin.enity.OrderInfo;
import com.gavin.repository.pojo.wfwOrderInfo;
import com.gavin.repository.wfwOrderInfoRepository;
import com.gavin.repository.service.wfwOrderInfoService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 * @Description: UP up UP
 * @author: Gavin
 * @date:2022/4/5 10:31
 */

@Service
public class wfwOrderInfoServiceImpl implements wfwOrderInfoService {

    @Autowired
   private wfwOrderInfoRepository wfwOrderInfoRepository;

    /**
     *
     * @param orderInfo   从commons传来的参数
     * @return
     */
    @Override
    public int createOrder(OrderInfo orderInfo) {
//        有可能传参的时候出错
        if (orderInfo==null){
            return -1;
        }
        wfwOrderInfo wfwOrderInfo = new wfwOrderInfo();
        wfwOrderInfo save =null;
        try {
            wfwOrderInfo.setNumber(orderInfo.getNumber());
            wfwOrderInfo.setPrice(orderInfo.getPrice());
//又可能save的时候出错
           save= wfwOrderInfoRepository.save(wfwOrderInfo);
        }
        catch(Exception ex){

            System.out.println(ex.getMessage());
            return -1;
        }
        return save.getOid();
    }
}

配置文件

server:
  port: 8001
spring:
  application:
    name: gavin-order-client
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://172.23.141.26:3306/gavin
    username: gavin
    password: 955945
    druid:
      db-type: mysql
    type: com.alibaba.druid.pool.DruidDataSource
eureka:
  instance:
    hostname: 192.168.135.1  #实例名
  client:
    service-url:
      defaultZone: http://192.168.135.1:7000/eureka  #eureka 地址
    register-with-eureka: true
    fetch-registry: true

远程调用接口~

/**
 * @FeignClient(name ="gavin-order-client" )调用的哪一个服务
 * <p>
 * eureka:
 * instance:
 * hostname: gavin-order-client  #这是服务提供者中被调用的服务名
 */

@Service
@FeignClient(value="gavin-order-client" /*,url = "localhost:8001"*/)
//@LoadBalancerClient(name = "mail-service", configuration = LoadBalancerConfiguration.class)
public interface OrderFeignClient {


    /**
     * @param orderInfo
     * @return
     * @PostMapping("/order/add") 是被调用者中控制器的路径
     */
    @PostMapping("/order/add")
    String add(OrderInfo orderInfo);


//    远程调用
    @PostMapping("/order/addOrderInfo")
    OrderInfo addOrder(@RequestBody  OrderInfo orderInfo);


}

服务调用配置~
这里还配置了负载均衡

server:
  port: 8200
spring:
  application:
    name: gavin-eurake-server

eureka:
  instance:
    hostname: gavin-eurake-server  #实例名
  client:
    service-url:
      defaultZone: http://192.168.135.1:7000/eureka  #eureka 地址
    register-with-eureka: false
    fetch-registry: true
gavin-order-client:
  ribbon:

    #NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule #配置规则 随机
    NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RoundRobinRule #配置规则 轮询
    #    NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RetryRule #配置规则 重试
    #    NFLoadBalancerRuleClassName: com.netflix.loadbalancer.WeightedResponseTimeRule #配置规则 响应时间权重
   # NFLoadBalancerRuleClassName: com.netflix.loadbalancer.BestAvailableRule #配置规则 最空闲连接策略
    ConnectTimeout: 500 #请求连接超时时间
    ReadTimeout: 1000 #请求处理的超时时间
    OkToRetryOnAllOperations: true #对所有请求都进行重试
    MaxAutoRetriesNextServer: 2 #切换实例的重试次数
    MaxAutoRetries: 1 #对当前实例的重试次数