Hystrix实操

1.依赖
  
        org.springframework.cloud
        spring-cloud-starter-netflix-hystrix
    

2.降级示例：
请求端：cloud-hystrim-order80

主启动类
@EnableFeignClients()
@SpringBootApplication
@EnableHystrix
public class OrderHystrimMain80 {
    public static void main(String[] args) {
        SpringApplication.run(OrderHystrimMain80.class,args);
    }
}


超时测试：
    //Hystrim >test
    @GetMapping("/timeOut/{id}")
    public String timeOut(@PathVariable("id") Integer id) throws InterruptedException {
        try {
            Thread.sleep(3000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
      String sssss=  paymentFeginService.payment_timeOut(id);
        log.info(">>>>>>>>>>>>>>>>>>ssssss:"+sssss);
        return  sssss ;

    }

调用远程出：
@Component
@FeignClient(value = "CLOUD-PAYMENT-SERVER",fallback = PaymentFeginServiceFallback.class)
public interface PaymentFeginService {
    @GetMapping("/payment/selectOne/{id}")
     CommonResult selectOne(@PathVariable(name = "id") Integer id);

    @GetMapping("/payment/timeOut")
     CommonResult timeOut();

    @GetMapping("/payment/payment_timeOut/{id}")
    String payment_timeOut(@PathVariable("id") Integer id);

    @GetMapping("/payment/get/zipkin")
     String  getZipkin();

}

PaymentFeginServiceFallback：这个类是请求端做的降级处理

@Component
public class PaymentFeginServiceFallback implements PaymentFeginService {
    @Override
    public CommonResult selectOne(Integer id) {
        return new  CommonResult(404,"客户端超时了:",null);
    }

    @Override
    public CommonResult timeOut() {
        return new  CommonResult(404,"客户端超时了:",null);    }

    @Override
    public String payment_timeOut(Integer id) {
        return "客户端超时了:" ; }

    @Override
    public String getZipkin() {
        return "测试链路返回";
    }
}

降级服务端示例：

    @GetMapping("/payment_timeOut/{id}")
    public String payment_timeOut(@PathVariable("id") Integer id) {
        String result = paymentService.payment_timeOut(id);
        log.info("<<<<<<<<"+result);
        return result;

    }


//超过3s就调用pay_timeOutHandler方法进行降级
    @HystrixCommand(fallbackMethod ="pay_timeOutHandler",commandProperties = { 
             @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds",value = "3000")})
    public String   payment_timeOut(Integer id){
        int num=6000;
        try {
            Thread.sleep(num);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return  "线程池："+Thread.currentThread().getName()+":id:"+id;
    }

//服务端降级
    public  String pay_timeOut(Integer id){
        return  "线程池："+Thread.currentThread().getName()+":超时了:"+id;
    }

3.0
服务端熔断示例：
@SpringBootApplication
@EnableEurekaClient
@EnableCircuitBreaker  //主要注解
public class PaymentHistrixMain8001 {
    public static void main(String[] args) {
        SpringApplication.run(PaymentHistrixMain8001.class, args);
    }





 //服务熔断  开启熔断器，请求次数超过10次,10s内，错误率达到60然后进行跳闸熔断，服务恢复正常后，继续调用链调用，不会出现降级后不可用情况（这里小于0抛异常，大于0请求真正常）
    @HystrixCommand(fallbackMethod ="paymentC ircuitBreak_fallback",commandProperties = {
            @HystrixProperty(name = "circuitBreaker.enabled",value = "true"),//是否开启断路器
            @HystrixProperty(name = "circuitBreaker.requestVolumeThreshold",value = "10"),//请求次数
            @HystrixProperty(name = "circuitBreaker.sleepWindowInMilliseconds",value ="10000"),//时间窗口期
            @HystrixProperty(name = "circuitBreaker.errorThresholdPercentage",value = "60")//失败率达到多少后跳闸
    })
    @GetMapping("/circuit/{id}")
    public String paymentCrircuitBreaker(@PathVariable("id")Integer id){
        if(id<0){
            throw new RuntimeException("******id不能为负数");
        }
        String sss= UUID.randomUUID().toString();
        return Thread.currentThread().getName()+"调用成功："+sss;
    }