本文以nacos为例

分为以下几个步骤

1. 下载nacos软件

2. pom文件配置

3. application.yml文件配置

4. 代码调用

5. 效果展示

一 . 下载nacos软件

1.1 下载nacos-server-2.2.0-BETA这个版本

nacos-server-2.2.0-BETA

1.2 修改nacos配置文件

打开bin目录下的startup.cmd，将第26行的

set MODE=“cluster”

改为：

set MODE=“standalone”

1.3 双击startup.cmd

如下图则表示启动成功

二. 项目中引入jar，配置文件pom.xml

Springboot升级为Springcloud版本一定要对应，不然就会有很多稀奇古怪的错误

本文是将2.7.5的Springboot升级为2021.0.7的Springcloud

如图：

以下是几个关键的配置：

完整的pom.xml配置文件

    4.0.0
    
        org.springframework.boot
        spring-boot-starter-parent
        2.7.5
         
    
    com.example
    cstudents
    0.0.1-SNAPSHOT
    students
    Demo project for Spring Boot
    
        1.8
        
    
    
        
            
                org.springframework.cloud
                spring-cloud-dependencies
                2021.0.7
                pom
                import
            
           
                com.alibaba.cloud
                spring-cloud-alibaba-dependencies
               2021.0.5.0
                pom
                import
            
        
    
    
    
        
            com.alibaba.cloud
            spring-cloud-starter-alibaba-nacos-config
        
        
            org.springframework.cloud
            spring-cloud-starter-bootstrap
        
        
            org.springframework.cloud
            spring-cloud-starter-openfeign
        
        
            org.springframework.cloud
            spring-cloud-starter-loadbalancer
        
        
            com.alibaba.cloud
            spring-cloud-starter-alibaba-nacos-discovery
            
                
                    jsr305
                    com.google.code.findbugs
                
                
                    HdrHistogram
                    org.hdrhistogram
                
            
        
        
        
            org.springframework.boot
            spring-boot-starter-web
        
        
        
            org.springframework.boot
            spring-boot-starter-test
            test
        
        
        
            org.springframework.boot
            spring-boot-starter-thymeleaf
        
        
        
            org.projectlombok
            lombok
        
        
        
            org.springframework.boot
            spring-boot-starter-data-jpa
        
        
        
            org.mybatis.spring.boot
            mybatis-spring-boot-starter
            2.2.1
        
        
        
            com.alibaba
            druid-spring-boot-starter
            1.2.15
        
        
        
            mysql
            mysql-connector-java
            8.0.31
        
        
        
            com.github.pagehelper
            pagehelper-spring-boot-starter
            1.4.5
        
        
        
            com.baomidou
            mybatis-plus-boot-starter
            3.4.2
        
        
        
        
        
            org.springframework.boot
            spring-boot-devtools
        
       
    
    
    
        
            spring-milestones
            Spring Milestones
            https://repo.spring.io/milestone
        
        
            repository.springframework.maven.release
            Spring Framework Maven Release Repository
            http://maven.springframework.org/milestone/
        
        
            org.springframework
             http://maven.springframework.org/snapshot
        
        
            spring-milestone
            Spring Maven MILESTONE Repository
            http://repo.spring.io/libs-milestone
        
        
            spring-release
            Spring Maven RELEASE Repository
            http://repo.spring.io/libs-release
        
    

    
        
            
            
            
                org.mybatis.generator
                mybatis-generator-maven-plugin
                1.3.6
                
                    GeneratorConfig.xml
                    true
                    true
                
            
        
    

在升级为Springcloud时，有些jar会有冲突，本文pom.xml文件中注释掉的就是冲突的jar，但是读者得根据自己的实际情况进行增删冲突jar，不过一般就是文中的这几个

三. application.yml文件配置

server:
  port: 9080
spring:
  application:
    name: consumer
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

注意事项：

4. 代码调用：

项目说明，项目有一个消费者（调用方），和两个生产者（被调用方）

4.1 生产者

生产者代码解析：

代码：

生产者application.yml：

server:
  port: 8081
spring:
  application:
    name: provider
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

生产者调用代码：

本代码中设置了三种情况：

消费者调用时传输一个参数，两个参数，一个集合的三种情况：

package com.example.test;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import java.util.Map;
@Controller
@RefreshScope
public class PrivodeController {
    @Value("${server.port}")
    String port;
    //传输一个参数
    @GetMapping("/hi")
    @ResponseBody
    public String hi(@RequestParam(value = "name", defaultValue = "forezp",required = false) String name) {
        System.out.println("666");
        String msg = "I receive msg 【" + name + "】" + ", i'm provider ,my port:" + port;
        System.out.println(msg);
        return msg;
    }
    //传输多个参数
    @GetMapping("/send")
    @ResponseBody
    public String send1(@RequestParam(value = "city", defaultValue = "Shanghai",required = false) String city,
                       @RequestParam(value = "site", defaultValue = "School",required = false) String site) {
        System.out.println("666");
        String msg = "My favorite city is " + city+ " , I want to go to " + site;
        System.out.println(msg);
        return msg;
    }
    //传输Map
    @GetMapping("/send2")
    @ResponseBody
    public String send2(@RequestParam Map data) {
        System.out.println("666");
        String msg = "My name is " + data.get("name")+ " , I am " + data.get("age") + " years old.";
        System.out.println(msg);
        return msg;
    }
}

生产者启动类：

package com.example;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.web.bind.annotation.RestController;
@MapperScan("com.example.mapper")
@SpringBootApplication
@RestController
@EnableDiscoveryClient
public class StudentsApplication {
    public static void main(String[] args) {
        SpringApplication.run(StudentsApplication.class, args);
    }
}

4.2 消费者

消费者代码解析：

消费者代码：

消费者application.yml

server:
  port: 9080
spring:
  application:
    name: consumer
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

消费者接口：

package com.example.test;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import java.util.Map;
@FeignClient(value = "provider" )
@RefreshScope
public interface ProviderClient {
    @GetMapping("/hi")
    String hi(@RequestParam(value = "name", defaultValue = "hello", required = false) String name);
    @GetMapping("/send1")
    String send1(@RequestParam(value = "city", defaultValue = "Shanghai", required = false) String city,
                @RequestParam(value = "site", defaultValue = "School", required = false) String site);
    @GetMapping("/send2")
    String send2(@RequestParam  Map data);
}

消费者实现类：

package com.example.test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import java.util.HashMap;
import java.util.Map;
@Controller
public class ConsumerController {
    @Autowired
    ProviderClient providerClient;
    //传输一个参数
    @GetMapping("/canos")
    @ResponseBody
    public String hiFeign(){
        System.out.println("哈哈哈哈哈哈哈哈哈哈哈哈哈哈哈哈");
        return providerClient.hi("你好，我这边发出了信息。。。。。");
    }
    //传输多个参数
    @GetMapping("/test")
    @ResponseBody
    public String hiNacos(){
        System.out.println("666");
        return providerClient.send1("Beijing","Tiananmen");
    }
    //传输Map
    @GetMapping("/test2")
    @ResponseBody
    public String hiNacos2(){
        System.out.println("777");
        Map data = new HashMap();
        data.put("name","Jack");
        data.put("age","18");
        return providerClient.send2(data);
    }
}

5. 效果展示：

双击启动nacos:

登录nocas:

用户名和密码默认是：nacos

启动一个消费者CStudents_C、两个生产者CStudents_P1、CStudents_P2

观察naocs控制面板：

可以对服务进行上线下线或者分配权重：

调用效果展示：