springcloud3-服务到服务调用ribbon及openfeign

package com.aaa.gs.config;
import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RandomRule;
import com.netflix.loadbalancer.RoundRobinRule;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;
import java.util.Random;
/**
• @ fileName:RibbonConfig
• @ description:
• @ author:zhz
• @ createTime:2022/2/19 9:53
• @ version:1.0.0/
@Configuration
public class RibbonConfig {
/*
• 实例化RestTemplate 并添加负载均衡配置
• @return
/
@Bean
@LoadBalanced //远程调用服务时，如果远程服务是多个，使用负载均衡
public RestTemplate restTemplate(){
return new RestTemplate();
}
/*
• 实例化IRule的子类 配置负载均衡算法
• @return
*/
@Bean
public IRule iRule(){
//随机
//return new RandomRule();
//轮询
return new RoundRobinRule();
}
}
• ribbon配置方法2：
启动类上添加注解：
@RibbonClient(name = “ribbonc”,configuration = RibbonConfig.class)
启动类上添加方法：
@Bean
@LoadBalanced
public RestTemplate restTemplate(){
return new RestTemplate();
}
编写MyRule:
@Configuration
public class RibbonConfig {
/**
• 实例化IRule的子类 配置负载均衡算法
• @return
*/
@Bean
public IRule iRule(){
//随机
//return new RandomRule();
//轮询
return new RoundRobinRule();
}
}

package com.aaa.gs.service.impl;
import com.aaa.core.bo.Order;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.baomidou.mybatisplus.extension.api.R;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.aaa.gs.dao.ProductDao;
import com.aaa.gs.entity.Product;
import com.aaa.gs.service.ProductService;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;
import springfox.documentation.spring.web.json.Json;
import javax.annotation.Resource;
import java.io.Serializable;
/**
• (Product)表服务实现类
• 
• @author makejava
• @since 2022-02-19 09:38:00
*/
@Service(“productService”)
public class ProductServiceImpl extends ServiceImpl implements ProductService {
@Resource
private RestTemplate restTemplate;
@Override
public Product getById(Serializable id) {
//根据商品id查询商品
Product product = this.baseMapper.selectById(id);
//int orderId = product.getOrderId;
//假如商品中有订单id
// url http://服务名称一定是想调用服务注册到注册中心的名称
R resultR = restTemplate.getForObject(“http://orderService/order/selectOne/8”, R.class);
//toJSONString json对象转为字符串
Order orderBo = JSON.parseObject(JSON.toJSONString(resultR.getData()), Order.class);
product.setOrder(orderBo);
//product.setR(resultR);
return product;
}
}

/try {
//让响应速度变慢
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}/
/**
• 配置负载均衡算法
• @return
*/
@Bean //
public IRule iRule(){
//使用随机算法
//return new RandomRule();
//使用轮询算法
//return new RoundRobinRule();
//按照响应时间，响应时间越短的，权重会高 更多的请求会到该服务器
return new WeightedResponseTimeRule();
}

package com.aaa.gs.config;
import com.netflix.client.config.IClientConfig;
import com.netflix.loadbalancer.AbstractLoadBalancerRule;
import com.netflix.loadbalancer.ILoadBalancer;
import com.netflix.loadbalancer.Server;
import java.util.List;
import java.util.concurrent.ThreadLocalRandom;
/**
• @ fileName:MyCustomRule
• @ description:
• @ author:zhz
• @ createTime:2022/2/19 11:21
• @ version:1.0.0/
public class MyCustomRule extends AbstractLoadBalancerRule {
public MyCustomRule() {
}
/*
• 从众多正常工作的服务器选择一台进行请求
• @param lb
• @param key
• @return
/
//SuppressWarnings抑制警告
@SuppressWarnings({“RCN_REDUNDANT_NULLCHECK_OF_NULL_VALUE”})
public Server choose(ILoadBalancer lb, Object key) {
if (lb == null) {
return null;
} else {
System.out.println(“ILoadBalancer开始--------”+lb+“--------ILoadBalancer开始”);
Server server = null;
//只要后台有参与负载均衡的服务器，必然要返回一个服务
while(server == null) {
/*
* 判断刚在获取到正常的服务器是否线程中断（出现故障）
*/
if (Thread.interrupted()) {
return null;
}
//获取正在运行的服务器
List upList = lb.getReachableServers();
System.out.println(“正在运行的服务器：”+upList);
List allList = lb.getAllServers();
System.out.println(“所有的服务器：”+allList);
int serverCount = allList.size();
System.out.println(“服务器数量：”+serverCount);
if (serverCount == 0) {
return null;
}
//随机算法
int index = this.chooseRandomInt(serverCount);
System.out.println(“随机出的数字必须是：0-”+(serverCount-1)+“中的一个是：”+index);
//按照随机的下标获取对象
server = (Server)upList.get(index);
System.out.println(“当前被选中的服务器为:”+server);
//再次判断
if (server == null) {
//让出CPU时间，让其他线程再次获取server
Thread.yield();
} else {
//再次判断没有活着
if (server.isAlive()) {
return server;
}
server = null;
Thread.yield();
}
}
return server;
}
}
• public Server choose(Object key)
{
return this.choose(this.getLoadBalancer(), key);
}
/**
• 随机算法方法
• @param serverCount
• @return
*/
protected int chooseRandomInt(int serverCount) {
return ThreadLocalRandom.current().nextInt(serverCount);
}
• public void initWithNiwsConfig(IClientConfig clientConfig) {
}
}

org.springframework.cloud spring-cloud-starter-openfeign 2) 创建评论表，创建项目，反向工程生成代码 CREATE TABLE tb_comment ( id bigint(20) PRIMARY key NOT NULL AUTO_INCREMENT , shop_id bigint(20) NOT NULL , order_id bigint(20) NULL DEFAULT NULL COMMENT '订单ID' , product_id bigint(20) NULL DEFAULT NULL COMMENT '订单为单一商品时，该字段有值' , member_nick_name varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL , product_name varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL , star int(3) NULL DEFAULT NULL COMMENT '评价星数：0->5' );
INSERT INTO tb_comment (id, shop_id, order_id, product_id, member_nick_name, product_name, star) VALUES (‘1’, ‘1’, ‘1’, ‘1’, ‘1’, ‘1’, ‘1’);
INSERT INTO tb_comment (id, shop_id, order_id, product_id, member_nick_name, product_name, star) VALUES (‘2’, ‘2’, ‘2’, ‘2’, ‘2’, ‘2’, ‘2’);
INSERT INTO tb_comment (id, shop_id, order_id, product_id, member_nick_name, product_name, star) VALUES (‘3’, ‘1’, ‘11’, ‘11’, ‘测试昵称’, ‘测试商品’, ‘11’);
INSERT INTO tb_comment (id, shop_id, order_id, product_id, member_nick_name, product_name, star) VALUES (‘24’, ‘0’, ‘0’, ‘0’, ‘1’, ‘1’, ‘0’);
INSERT INTO tb_comment (id, shop_id, order_id, product_id, member_nick_name, product_name, star) VALUES (‘25’, ‘0’, ‘0’, ‘0’, ‘1’, ‘1’, ‘0’);
INSERT INTO tb_comment (id, shop_id, order_id, product_id, member_nick_name, product_name, star) VALUES (‘28’, ‘0’, ‘0’, ‘0’, ‘1’, ‘1’, ‘0’);