dubbo超时重试

dubbo超时重试概述

consumer端和provider端都可以设置timeout。

超时优先级：consumer方法级>provider方法级>consumer接口级>provider接口级>consumer级>provider级

当consumer端调用超时，会触发重试调用。

重试对应的配置属性是retries。默认的重试次数是2。就是说，当调用超时，会最多重试2次，如果仍然失败，会提示异常。

对于查询或删除来说，接口重试是幂等的。

对于新增数据，如果retries>0，则要做幂等处理，否则会造成重复数据入库而产生bug。安全起见，可单独设置retries=0。

【说明】在直连的情况下，是不会触发重试的。

代码

Provider application.yml dubbo配置：

dubbo:
  application:
    name: zhanggz-dubbodemo
  registry:
#    address: N/A
    address: zookeeper://127.0.0.1:2181
  protocol:
    port: 28088
    name: dubbo
  scan:
    base-packages: dubbodemo.provider
  provider:
    timeout: 2200
    retries: 3

View Code

Provider代码：

package dubbodemo.provider;

import dubbodemo.contract.HelloWord;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.RandomUtils;
import org.apache.dubbo.config.annotation.Service;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@Slf4j
@Service(retries = 3)
@SpringBootApplication
public class ProviderApplication implements HelloWord {
    public static void main(String[] args) {
        SpringApplication.run(ProviderApplication.class);
    }

    public String add(String str) {
        log.info("add入参:{}", str);
        long start = System.currentTimeMillis();
        try {
//int i=1/0;
            try {
                int r = RandomUtils.nextInt(1000, 2000);
                log.info("sleep time={}", r);
                Thread.sleep(r);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            return "test retry:" + str;
        } finally {
            log.info("duration={}", System.currentTimeMillis() - start);
        }
    }

    public String say() {
        return ("hello");
    }
}

View Code

Consumer application.yml dubbo配置：

dubbo:
  application:
    name: zhanggz-dubbodemo-consumer
  registry:
    address: zookeeper://127.0.0.1:2181
  #    address: N/A
  protocol:
    name: dubbo
  consumer:
    timeout: 1000
#    retries: 0

View Code

Consumer代码：

package dubbodemo.consumer;

import dubbodemo.contract.HelloWord;
import lombok.extern.slf4j.Slf4j;
import org.apache.dubbo.config.annotation.Reference;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@Slf4j
@RunWith(SpringRunner.class)
@SpringBootTest
public class DubboConsumerTest {
    @Reference(/*url = "dubbo://localhost:28088",*/)
    private HelloWord helloWord;

    @Test
    public void testAddRetry() {
        long start = System.currentTimeMillis();
        log.info("请求开始...");
        try {
            String str = helloWord.add("str");
            log.info("返回值={}", str);
        } finally {
            log.info("duration=={}", System.currentTimeMillis() - start);
        }
    }
}

View Code

接口定义：

package dubbodemo.contract;

public interface HelloWord {
    String say();

    String add(String str);
}

测试结论

--------consumer不设置timeout（默认值=1000ms），改变provider的timeout值

【provider】
provider:
timeout: 1000
2020-07-23 18:53:57.427 INFO 13356 --- [:20880-thread-2] dubbodemo.provider.ProviderApplication : duration=2000
2020-07-23 18:53:57.432 WARN 13356 --- [:20880-thread-2] o.apache.dubbo.rpc.filter.TimeoutFilter : [DUBBO] invoke time out. method: add arguments: [str] , url is dubbo://192.168.40.69:20880/dubbodemo.contract.HelloWord?anyhost=true&application=zhanggz-dubbodemo&bean.name=ServiceBean:dubbodemo.contract.HelloWord&bind.ip=192.168.40.69&bind.port=20880&deprecated=false&dubbo=2.0.2&dynamic=true&generic=false&interface=dubbodemo.contract.HelloWord&methods=add,say&pid=13356&qos.enable=false&register=true&release=2.7.3&side=provider&timeout=1000&timestamp=1595501612605, invoke elapsed 2005 ms., dubbo version: 2.7.3, current host: 192.168.40.69

【provider】
provider:
timeout: 2200
2020-07-23 18:57:16.949 INFO 12280 --- [:20880-thread-2] dubbodemo.provider.ProviderApplication : duration=2000
（没有提示invoke timeout）

【consumer都会收到timeout异常】
2020-07-23 18:53:56.273 INFO 13216 --- [ main] dubbodemo.consumer.DubboConsumerTest : duration==1040

org.apache.dubbo.rpc.RpcException: Invoke remote method timeout. method: add, provider: dubbo://localhost:20880/dubbodemo.contract.HelloWord?application=zhanggz-dubbodemo-consumer&interface=dubbodemo.contract.HelloWord&lazy=false&pid=13216&qos.enable=false&register.ip=192.168.40.69&remote.application=&side=consumer&sticky=false, cause: org.apache.dubbo.remoting.TimeoutException: Waiting server-side response timeout by scan timer. start time: 2020-07-23 18:53:55.250, end time: 2020-07-23 18:53:56.272, client elapsed: 106 ms, server elapsed: 916 ms, timeout: 1000 ms, request: Request [id=0, version=2.0.2, twoway=true, event=false, broken=false, data=RpcInvocation [methodName=add, parameterTypes=[class java.lang.String], arguments=[str], attachments={path=dubbodemo.contract.HelloWord, interface=dubbodemo.contract.HelloWord, version=0.0.0}]], channel: /192.168.40.69:1813 -> /192.168.40.69:20880

----------------------------- 服务端停止运行后，客户端无法启动

org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘dubbodemo.consumer.DubboConsumerTest‘: Injection of @Reference dependencies is failed; nested exception is org.apache.dubbo.rpc.RpcException: Fail to create remoting client for service(dubbo://localhost:20880/dubbodemo.contract.HelloWord?application=zhanggz-dubbodemo-consumer&codec=dubbo&heartbeat=60000&interface=dubbodemo.contract.HelloWord&lazy=false&pid=5236&qos.enable=false&register.ip=192.168.40.69&remote.application=&side=consumer&sticky=false&timeout=2200): client(url: dubbo://localhost:20880/dubbodemo.contract.HelloWord?application=zhanggz-dubbodemo-consumer&codec=dubbo&heartbeat=60000&interface=dubbodemo.contract.HelloWord&lazy=false&pid=5236&qos.enable=false&register.ip=192.168.40.69&remote.application=&side=consumer&sticky=false&timeout=2200) failed to connect to server localhost/127.0.0.1:20880, error message is:Connection refused: no further information: /192.168.40.69:20880

----------------------------- consumer端设置dubbo.consumer.check=false。则可以启动consumer服务。不过，当调用远程服务的时候，由于远程服务处于停止状态，所以会报错。org.apache.dubbo.rpc.RpcException: Failed to invoke remote method: add, provider: dubbo://localhost:20880/dubbodemo.contract.HelloWord?application=zhanggz-dubbodemo-consumer&check=false&interface=dubbodemo.contract.HelloWord&lazy=false&pid=12504&qos.enable=false&register.ip=192.168.40.69&remote.application=&side=consumer&sticky=false&timeout=2200, cause: message can not send, because channel is closed . url:dubbo://localhost:20880/dubbodemo.contract.HelloWord?application=zhanggz-dubbodemo-consumer&check=false&codec=dubbo&heartbeat=60000&interface=dubbodemo.contract.HelloWord&lazy=false&pid=12504&qos.enable=false&register.ip=192.168.40.69&remote.application=&side=consumer&sticky=false&timeout=2200

----------------------------------

consumer端，设置retries=3
2020-07-24 17:12:57.389 INFO 7468 --- [ main] dubbodemo.consumer.DubboConsumerTest : 请求开始...
2020-07-24 17:13:00.202 INFO 7468 --- [ main] dubbodemo.consumer.DubboConsumerTest : 返回值=test retry:str
2020-07-24 17:13:00.202 INFO 7468 --- [ main] dubbodemo.consumer.DubboConsumerTest : duration==2813

provider端：最多会被执行1+retries=4次
2020-07-24 17:12:57.540 INFO 2372 --- [28088-thread-17] dubbodemo.provider.ProviderApplication : add入参:str
2020-07-24 17:12:57.541 INFO 2372 --- [28088-thread-17] dubbodemo.provider.ProviderApplication : r=1169
2020-07-24 17:12:58.444 INFO 2372 --- [28088-thread-18] dubbodemo.provider.ProviderApplication : add入参:str
2020-07-24 17:12:58.444 INFO 2372 --- [28088-thread-18] dubbodemo.provider.ProviderApplication : r=1934
2020-07-24 17:12:58.711 INFO 2372 --- [28088-thread-17] dubbodemo.provider.ProviderApplication : duration=1170
2020-07-24 17:12:59.461 INFO 2372 --- [28088-thread-19] dubbodemo.provider.ProviderApplication : add入参:str
2020-07-24 17:12:59.461 INFO 2372 --- [28088-thread-19] dubbodemo.provider.ProviderApplication : r=736
2020-07-24 17:13:00.198 INFO 2372 --- [28088-thread-19] dubbodemo.provider.ProviderApplication : duration=737
2020-07-24 17:13:00.379 INFO 2372 --- [28088-thread-18] dubbodemo.provider.ProviderApplication : duration=1935

dubbo超时重试

原文：https://www.cnblogs.com/buguge/p/13373611.html