feign中开启熔断的书写步骤

/**   1、在pom.xml中引入依赖    2、在application.yaml中开启hystrix

     3、在方法上配置熔断类     4、书写接口的实现类

**/

//1、在pom.xml中引入依赖

<?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>cloud-demo</artifactId>
        <groupId>com.hope.demo</groupId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>consumer-demo</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
    </dependencies>
</project>
//2、在application.yaml中开启hystrix

server:
  port: 8083
spring:
  application:
    name: consumer-service
eureka:
  client:
    service-url:
       defaultZone: http://127.0.0.1:10086/eureka,http://127.0.0.1:10087/eureka
    registry-fetch-interval-seconds: 30
  instance:
    prefer-ip-address: true
    ip-address: 127.0.0.1
user-service:
    ribbon:
      NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule
hystrix:
     command:
         default:
             execution:
                isolation:
                   thread:
                      timeoutInMilliseconds: 6000
ribbon:
     ReadTimeout: 6000
     ConnectTimeout: 6000
feign:
     hystrix:
        enabled: true

//3、在方法上配置熔断类
package com.hope.Consumer.client;

import com.hope.Consumer.pojo.User;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;

/**
 * @author newcityman
 * @date 2019/12/19 - 19:42
 */
@FeignClient(value = "user-service",fallback =  UserClientFallback.class )
public interface UserClient {
    @GetMapping("user/{id}")
    User queryById(@PathVariable("id") Long id);
}

//4、书写接口的实现类

package com.hope.Consumer.client;

import com.hope.Consumer.pojo.User;
import org.springframework.stereotype.Component;

/**
 * @author newcityman
 * @date 2019/12/19 - 22:52
 */
@Component
public class UserClientFallback implements UserClient {
    @Override
    public User queryById(Long id) {
        User user = new User();
        user.setName("未知用户");
        return user;
    }
}