4.Hystrix实现Timeout降级

1.Controller添加timeout方法

package com.imooc.springcloud;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class Controller {

    @Autowired
    private MyService myService;

    @GetMapping("/fallback")
    public String fallback(){
        return myService.error();
    }

    @GetMapping("/timeout")
    public String timeout(Integer timeout){
        return myService.error();
        myService.retry(timeout);
    }


}

2.Fallback实现retry方法

package com.imooc.springcloud.hystrix;

import com.imooc.springcloud.Friend;
import com.imooc.springcloud.MyService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

@Slf4j
@Component
public class Fallback implements MyService {

    @Override
    public String error() {
        log.info("Fallback:I am not a back sheep any more");
        return "Fallback:I am not a back sheep any more";
    }

    @Override
    public String sayHi() {
        return null;
    }

    @Override
    public Friend sayHiPost(Friend friend) {
        return null;
    }

    @Override
    public String retry(int timeout) {
        return "You are late !";
    }
}

3.retry的服务提供者

package com.imooc.springcloud;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.logging.Log;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

/**
 * Created by 半仙.
 */
@RestController
@Slf4j
public class Controller implements IService {

    @Value("${server.port}")
    private String port;


    @GetMapping("/sayHi2")
    public String sayHi2() {
        return "This is " + port;
    }

    @Override
    public String sayHi() {
        return "This is " + port;
    }

    @Override
    public Friend sayHiPost(@RequestBody Friend friend) {
        log.info("You are " + friend.getName());
        friend.setPort(port);
        return friend;
    }

    @Override
    public String retry(@RequestParam(name = "timeout") int timeout) {
        while (--timeout >= 0) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
            }
        }
        log.info("retry " + port);
        return port;
    }

    @Override
    public String error() {
        throw new RuntimeException("black sheep");
    }
}

3.配置文件超时的配置

spring.application.name=hystrix-consumer
server.port=50000
spring.main.allow-bean-definition-overriding=true
eureka.client.serviceUrl.defaultZone=http://localhost:20000/eureka/

# 开启Feign下面的Hystrix功能
feign.hystrix.enabled=true
# 是否开启服务降级
hystrix.command.default.fallback.enabled=true
#########################################超时配置##########################################################
# 全局超时
hystrix.command.default.execution.timeout.enabled=true
# 超时时间
hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds=1000
# 超时以后终止线程
hystrix.command.default.execution.isolation.thread.interruptOnTimeout=true
# 取消的时候终止线程
hystrix.command.default.execution.isolation.thread.interruptOnFutureCancel=true
# hystrix.command.MyService#retry(int).execution.isolation.thread.timeoutInMilliseconds=3000


# 每台机器最大重试次数
feign-client.ribbon.MaxAutoRetries=0
# 可以再重试几台机器
feign-client.ribbon.MaxAutoRetriesNextServer=0
# 连接超时
feign-client.ribbon.ConnectTimeout=1000
# 业务处理超时
feign-client.ribbon.ReadTimeout=2000
# 在所有HTTP Method进行重试
feign-client.ribbon.OkToRetryOnAllOperations=false

4.在具体方法上配置配置hystrix 超时变量

配置文件里
MyService#retry(int)：方法的签名

hystrix.command.MyService#retry(int).execution.isolation.thread.timeoutInMilliseconds=3000

5.方法的前面很复杂怎么办？

通过Feign.configKey工具来获取，通过反射方式？

        System.out.println(Feign.configKey(MyService.class,
                MyService.class.getMethod("retry", int.class)));