SpringCloud 实战十五：Hystrix统配服务降级 FeignFallBack

1、服务提供者端故意制造异常

package com.laoxu.springcloud.service;

import com.netflix.hystrix.contrib.javanica.annotation.DefaultProperties;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty;
import org.springframework.stereotype.Service;

import java.util.concurrent.TimeUnit;

@Service
@DefaultProperties(defaultFallback = "payment_Globle_FallbackMethod")
public class PaymentService {

    //正常访问返回ok的方法
    @HystrixCommand
    public String paymentInfo_OK(Integer id){
        int age = 10/0;
        return "线程池：" + Thread.currentThread().getName() + "paymentInfo_OK, id:" + id + "\t" + "哈哈";
    }

    @HystrixCommand(fallbackMethod = "paymentInfo_TimeoutHandler", commandProperties = {
            @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds", value = "2000")
    })
    public String paymentInfo_Timeout(Integer id){
        long second = 3;
        try {
            TimeUnit.SECONDS.sleep(second);
        }catch (InterruptedException e){
            e.printStackTrace();
        }
        return "线程池：" + Thread.currentThread().getName() + "paymentInfo_Timeout, id:" + id + "\t" + "哈哈" + "耗时" +second+"秒钟";
    }

    public String paymentInfo_TimeoutHandler(Integer id){
        return "线程池：" + Thread.currentThread().getName() + "paymentInfo_Timeout, id:" + id + "\t" + "系统繁忙！请稍后再试！！";
    }

    //全局fallback方法
    public String payment_Globle_FallbackMethod(){
        return "系统繁忙！请稍后再试！！";
    }
}

2、在消费者端新建服务降级类继承服务

package com.laoxu.springcloud.service;

import org.springframework.stereotype.Component;

@Component
public class PaymentFallBackService implements PaymentHystrixService {

    public String paymentInfo_OK(Integer id) {
        return "PaymentFallBackService fall back-- paymentInfo_OK";
    }

    public String paymentInfo_Timeout(Integer id) {
        return "PaymentFallBackService fall back-- paymentInfo_Timeout";
    }
}

3、在消费者端 feign调用端指定服务降级类进行通配降级

package com.laoxu.springcloud.service;

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 = "CLOUD-PROVIDER-HYSTRIX-PAYMENT", fallback = PaymentFallBackService.class)
public interface PaymentHystrixService {

    @GetMapping("/payment/hystrix/ok/{id}")
    public String paymentInfo_OK(@PathVariable("id") Integer id);

    @GetMapping("/payment/hystrix/timeout/{id}")
    public String paymentInfo_Timeout(@PathVariable("id") Integer id);
}

4、配置开启服务降级

server:
  port: 80
spring:
  application:
    name: cloud-consumer-feign-hystrix-order

eureka:
  client:
    # 将自己注册进eureka中心
    register-with-eureka: false
    service-url:
      defaultZone: http://eureka7001.com:7001/eureka, http://eureka7002.com:7002/eureka


feign:
  hystrix:
    enabled: true

5、访问：http://localhost/consumer/payment/hystrix/ok/31

调用通配的异常方法