nacos user服务消费者（openfeign）访问notice集群-马育民老师

# 创建工程

创建 user_openfeign 工程

[![](https://www.malaoshi.top/upload/pic/docker/20200622221341.png)](https://www.malaoshi.top/upload/pic/docker/20200622221341.png)

# 添加依赖pom.xml
```
<dependencies>
    
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>
```

# application.yml配置文件

在`resources`文件夹中创建`application.yml`配置文件

```
server:
  port: 9001   # 服务端口
spring:
  application:
    name: user-consumer   # 注册服务名
  cloud:
    nacos:
      discovery:
        server-addr: 106.13.165.100:8848   # nacos地址

# 配置服务提供者url，便于在类中调用
service-provider:
  notice-provider:
    name: notice-provider
    urls:
      notice: /notice/{id}
      getNoteById: /getNoteById/{id}

# 负载均衡策略
notice-provider:
  ribbon:
    NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule
```

负载均衡策略参见：
https://www.malaoshi.top/show_1EF5iJxtARRK.html
https://www.malaoshi.top/show_1EF5iInH93Gc.html

# 主启动类

```
package top.malaoshi;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;

@SpringBootApplication
@EnableFeignClients
@EnableDiscoveryClient
public class UserFeignMain {
    public static void main(String[] args) {
        SpringApplication.run(UserFeignMain.class, args);
    }
}
```

# FeignClient接口
```
package top.malaoshi.clients;

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;

@Component
@FeignClient(value="${service-provider.notice-provider.name}") //微服务名称
public interface NoticeClient {
    @GetMapping(value = "${service-provider.notice-provider.urls.notice}")
    public String notice(@PathVariable("id") String id);
}
```

# controller

```
package top.malaoshi.controller;

import lombok.extern.slf4j.Slf4j;
import top.malaoshi.clients.NoticeClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

@RestController
@Slf4j
public class FollowCtrl {

@Resource
    private NoticeClient noticeClient;

@GetMapping(value="/follow/{id}")
    public String follow(@PathVariable("id") String id){
        log.info("user_openfeign:id:"+id);
        return noticeClient.notice(id);
    }
}
```

# 修改notice服务的NoticeCtrl

打印一段信息，区别user调用的是哪一个notice服务

```
package top.malaoshi.controllers;

import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

@RestController
@Slf4j //添加注解
public class NoticeCtrl {

@GetMapping(value = "/notice/{id}")
    public String notice(@PathVariable String id) {
        log.info("id--",id); //直接使用
        return "通知成功！ " + id;
    }

}

```

# 测试

### 启动
启动nacos
启动2个notice
启动user_openfeign

### 测试服务

访问 http://localhost:9001/follow/1 能够随机调用1个notice

其中一个notice服务会打印信息

原文出处：http://malaoshi.top/show_1EF5lAmIO8bi.html