spring cloud 项目搭建：3、Feign接口负载均衡

男娘i 2023-10-08 12:51 14阅读 0赞

#### 文章目录 ####

*  写在前面
 *   *  1、Feign介绍
     *  2、使用Feign
     *   *  2.1、往springcloud-api中添加service
         *  2.2、新建服务消费者模块springcloud-consumer-dept-feign
         *  2.3、启动、测试

## 写在前面 ##

*  [ spring cloud 项目搭建 ：1、eureka 服务治理][spring cloud _ _1_eureka]: https://blog.csdn.net/a\_\_int\_\_/article/details/116791386
 *  [ spring cloud 项目搭建 ：2、ribbon客户端负载均衡][spring cloud _ _2_ribbon]: https://blog.csdn.net/a\_\_int\_\_/article/details/116797413
 *  [ spring cloud 项目搭建 ：4、Hystrix服务熔断][spring cloud _ _4_Hystrix]: https://blog.csdn.net/a\_\_int\_\_/article/details/117442286

### 1、Feign介绍 ###

ribbon和feign区别:

*  ribbon通过微服务名字在客户端调用
 *  feign同过接口和注解在微服务端调用（实际上是在ribbon的基础上封装的，更简单）

### 2、使用Feign ###

#### 2.1、往springcloud-api中添加service ####

在springcloud-api添加feign的依赖

<dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-feign</artifactId>
                <version>1.4.6.RELEASE</version>
            </dependency>

新建接口DeptClientService.java

import com.demo.bean.Dept;
    import org.springframework.cloud.openfeign.FeignClient;
    import org.springframework.stereotype.Component;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    import java.util.List;
    
    @Component
    @FeignClient(value = "SPRINGCLOUD-PROVIDER-DEPT")
    public interface DeptClientService {
        
        @GetMapping("/dept/get/{id}")
        public Dept get(@PathVariable("id") Long id);
        @GetMapping("/dept/get")
        public List<Dept> getList();
        @RequestMapping("/dept/add")
        public Boolean add(Dept dept);
    }

![在这里插入图片描述][20210601140746578.png]

#### 2.2、新建服务消费者模块springcloud-consumer-dept-feign ####

新建包org.example.controller  
新建类DeptConsumerController

import com.demo.bean.Dept;
    import com.demo.service.DeptClientService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import java.util.List;
    
    @RestController
    public class DeptConsumerController {
        
        @Autowired
        private DeptClientService service = null ;
        @RequestMapping("consumer/dept/get/{id}")
        public Dept get(@PathVariable("id") Long id){
        
            return this.service.get(id);
        }
        @RequestMapping("consumer/dept/add")
        public Boolean add(Dept dept){
        
            return this.service.add(dept);
        }
        @RequestMapping("consumer/dept/get")
        public List<Dept> getList(){
        
            return this.service.getList();
        }
    }

新建启动类ConsumerApplication\_Feign

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
    import org.springframework.cloud.openfeign.EnableFeignClients;
    
    @SpringBootApplication
    @EnableEurekaClient
    @EnableFeignClients(basePackages = {
        "com.demo"})
    public class ConsumerApplication_Feign {
        
        public static void main(String[] args) {
        
            SpringApplication.run(ConsumerApplication_Feign.class,args);
        }
    }

新建配置文件application.yml

server.port: 80
    # eureka配置
    eureka:
      client:
        register-with-eureka: false # 服务消费者，不需要往注册中心注册
        service-url:
          defaultZone: http://127.0.0.1:7001/eureka/,http://127.0.0.2:7002/eureka/,http://127.0.0.3:7003/eureka/

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <parent>
            <artifactId>clouddemo</artifactId>
            <groupId>org.example</groupId>
            <version>1.0-SNAPSHOT</version>
        </parent>
        <modelVersion>4.0.0</modelVersion>
    
        <artifactId>springcloud-consumer-dept-feign</artifactId>
    
        <dependencies>
            
            <dependency>
                <groupId>org.example</groupId>
                <artifactId>springcloud-api</artifactId>
                <version>1.0-SNAPSHOT</version>
                <scope>compile</scope>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-devtools</artifactId>
            </dependency>
            
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-ribbon</artifactId>
                <version>1.4.6.RELEASE</version>
            </dependency>
            
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-eureka</artifactId>
                <version>1.4.6.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-feign</artifactId>
                <version>1.4.6.RELEASE</version>
            </dependency>
        </dependencies>
    
    </project>

#### 2.3、启动、测试 ####

分别启动下面这几个模块  
![在这里插入图片描述][20210601141654630.png]  
访问http://127.0.0.1/consumer/dept/get  
![在这里插入图片描述][20210601141734805.png]

[spring cloud _ _1_eureka]: https://blog.csdn.net/a__int__/article/details/116791386
[spring cloud _ _2_ribbon]: https://blog.csdn.net/a__int__/article/details/116797413
[spring cloud _ _4_Hystrix]: https://blog.csdn.net/a__int__/article/details/117442286
[20210601140746578.png]: https://img-blog.csdnimg.cn/20210601140746578.png
[20210601141654630.png]: https://img-blog.csdnimg.cn/20210601141654630.png
[20210601141734805.png]: https://img-blog.csdnimg.cn/20210601141734805.png