springcloud-feign调用服务
在这里需要说一下feign只是一种符合我们接口调用的实现，不一定就要使用这个技术
在如下代码的基础上改造
springcloud-自定义ribbon负载均衡算法
1、修改springcloud-api文件
1. 添加依赖
添加feign的依赖，完整的pom文件如下
<?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>springcloud</artifactId>
<groupId>org.example</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>springcloud-api</artifactId>
<dependencies>
<!-- lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.18</version>
</dependency>
<!-- mybatis_plus -->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.0.5</version>
</dependency>
<!-- feign -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-feign</artifactId>
<version>1.4.6.RELEASE</version>
</dependency>
</dependencies>
</project>
2. 编写feignservice，通过feign调用服务
新建一个service文件夹，在文件夹下新建一个UserFeignService接口
具体代码如下：
package com.hzxy.springcloud.service;
import com.hzxy.springcloud.model.User;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RequestMapping;
import java.util.List;
@Component
@FeignClient(value = "springcloud-provider-user") // value 参数是服务提供者的服务名称
public interface UserClientService {
// 请求提供者的url
@RequestMapping("/hello")
public List<User> Hi();
}
2、编写新的消费者消费服务
大部分代码和springcloud-consumer-user-80一样，为了区别，所以新建了一个
1. 新建一个maven项目，springcloud-consumer-user-feign
2. 导入依赖
pom文件如下
<?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>springcloud</artifactId>
<groupId>org.example</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>springcloud-consumer-user-feign</artifactId>
<dependencies>
<!-- ribbon -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-ribbon</artifactId>
<version>1.4.6.RELEASE</version>
</dependency>
<!-- eureka -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
<version>1.4.6.RELEASE</version>
</dependency>
<!-- feign -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-feign</artifactId>
<version>1.4.6.RELEASE</version>
</dependency>
<!-- 我们需要拿到实体类 ，所以配置api module -->
<dependency>
<groupId>org.example</groupId>
<artifactId>springcloud-api</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<!-- springboot -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- 热部署工具 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
</dependency>
<!-- 数据库驱动 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
</dependencies>
</project>
3. 编写配置文件
server:
port: 80
spring:
application:
name: springcloud-consumer-user
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis_plus?serverTimezone=GMT%2B8
username: root
password: 520China
# Eureka配置
eureka:
client:
register-with-eureka: false # 不向Eureka注册自己
service-url:
defaultZone: http://ybg.eureka1.com:7001/eureka/,http://ybg.eureka2.com:7002/eureka/ # 向哪个地方获取Eureka服务
4. 新建config文件夹，编写ConfigBean类
代码如下
package com.hzxy.springcloud.config;
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;
@Configuration
public class ConfigBean {
// @Configuration -- spring applicationContext.xml
// 配置负载均衡实现RestTemplate
// RoundRobinRule 轮询
// RandomRule 随机
// AvailabilityFilteringRule 会先过滤掉，跳闸，访问故障的服务，对剩下的进行轮询
// RetryRule 会先按照轮询获取服务，如果服务获取失败，则会在指定时间内进行，重试
@Bean
@LoadBalanced //ribbon
public RestTemplate getRestTemplate(){
return new RestTemplate();
}
}
5. 新建controller文件夹，编写UserController类
代码如下
package com.hzxy.springcloud.controller;
import com.hzxy.springcloud.model.User;
import com.hzxy.springcloud.service.UserClientService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
import java.util.List;
@RestController
public class UserController {
// @Resource
// private RestTemplate restTemplate; //提供多种便捷访问远程http服务方法，简单的Restful服务模板
// private static final String REST_URL = "http://localhost:8001/hello";
//ribbon 我们这里的地址，应该是一个变量，通过服务名来访问
// private static final String REST_URL = "http://springcloud-provider-user/hello";
//
//
// @RequestMapping("/hi")
// public List<User> Hi(){
// return restTemplate.getForObject(REST_URL,List.class);
// }
@Resource
private UserClientService userClientService;
@RequestMapping("/hi")
public List<User> Hi(){
return this.userClientService.Hi();
}
}
6. 编写启动类
代码如下
package com.hzxy.springcloud;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
// ribbon 和 Eureka 整合以后，客户端可以直接调用，不用关心ip地址和端口号
@SpringBootApplication
@EnableEurekaClient //自动配置
@EnableFeignClients(basePackages = {
"com.hzxy.springcloud"})
public class FeignConsumer_80 {
public static void main(String[] args) {
SpringApplication.run(FeignConsumer_80.class,args);
}
}
3、测试
再次请求http://ybg.eureka1.com/hi，等一会儿，她能出现如下页面，测试成功1
