前言
定時調(diào)度基本是每個項目都會遇到的業(yè)務(wù)場景,一般地,都會通過任務(wù)調(diào)度工具執(zhí)行定時任務(wù)完成,定時任務(wù)有兩點缺陷,一、定時任務(wù)執(zhí)行頻度限制,實際執(zhí)行的時間可能會晚于理想的設(shè)定時間,例如,如果要通過定時任務(wù)實現(xiàn)在下單后15分鐘仍未支付則取消訂單的功能,假設(shè)定時任務(wù)的執(zhí)行頻度為每分鐘執(zhí)行一次,對于有些訂單而言,其實際取消時間是介于15-16分鐘之間,不夠精確;二、定時任務(wù)執(zhí)行需要時間,定時任務(wù)的執(zhí)行也需要時間,如果業(yè)務(wù)場景的數(shù)據(jù)量較大,執(zhí)行一次定時任務(wù)需要足夠長的時間,進一步放大了缺點一。
Redisson延時隊列
在上一篇文章中延時隊列-基于RabbitMq延時消息插件實現(xiàn)的延時隊列
介紹了一種基于RabbitMq延時消息插件實現(xiàn)的延時隊列,除此之外,另一種比較常見的實現(xiàn)方式是Redisson延時隊列。
在Redisson官網(wǎng)文檔中,使用延時隊列的代碼如下:
RQueue<String> distinationQueue = ...
RDelayedQueue<String> delayedQueue = getDelayedQueue(distinationQueue);
// 10秒鐘以后將消息發(fā)送到指定隊列
delayedQueue.offer("msg1", 10, TimeUnit.SECONDS);
// 一分鐘以后將消息發(fā)送到指定隊列
delayedQueue.offer("msg2", 1, TimeUnit.MINUTES);
當(dāng)該延時隊列不需要使用時,應(yīng)當(dāng)主動銷毀
RDelayedQueue<String> delayedQueue = ...
delayedQueue.destroy();
Redisson的延時隊列是對另一個隊列的再包裝,使用時要先將延時消息添加到延時隊列中,當(dāng)延時隊列中的消息達到設(shè)定的延時時間后,該延時消息才會進行進入到被包裝隊列中,因此,我們只需要對被包裝隊列進行監(jiān)聽即可。
代碼部分
在上一篇文章中,我們定義了DelayMessageManager延時消息管理器并提供了一種基于RabbitMq的實現(xiàn),本文中我們再提供一種基于Redisson延時隊列的實現(xiàn)即可。
package com.cube.share.delay.manager;
import cn.hutool.core.thread.ThreadUtil;
import com.cube.share.delay.handler.DelayMessageHandler;
import com.cube.share.delay.message.DelayMessage;
import com.cube.share.delay.message.DelayMessageType;
import lombok.extern.slf4j.Slf4j;
import org.redisson.Redisson;
import org.redisson.api.RBlockingQueue;
import org.redisson.api.RDelayedQueue;
import org.redisson.api.RedissonClient;
import org.springframework.stereotype.Component;
import java.util.Arrays;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import static com.cube.share.base.utils.SpringContextUtil.getBean;
/**
* @author cube.li
* @date 2021/10/11 20:59
* @description 基于redisson實現(xiàn)的延時消息管理器
*/
@Component
@Slf4j
public class RedissonDelayMessageManager implements DelayMessageManager {
private RedissonClient redissonClient = Redisson.create();
private RBlockingQueue<DelayMessage> rBlockingQueue = redissonClient.getBlockingDeque("redisson-delay-message-queue");
private RDelayedQueue<DelayMessage> rDelayedQueue = redissonClient.getDelayedQueue(rBlockingQueue);
private final Map<DelayMessageType, DelayMessageHandler> handlerMap = new ConcurrentHashMap<>(16);
@Override
public void add(DelayMessage message) {
if (rDelayedQueue.contains(message)) {
return;
}
log.info("redisson-delay-message-queue,add message = {}", message);
rDelayedQueue.offer(message, message.getProperties().getExpire(), message.getProperties().getTimeUnit());
}
@Override
public boolean remove(DelayMessage message) {
return rDelayedQueue.remove(message);
}
@Override
public void destroy() {
rDelayedQueue.destroy();
}
@Override
public void afterPropertiesSet() {
Arrays.stream(DelayMessageType.values()).forEach(delayMessageType -> handlerMap.put(delayMessageType, getBean(delayMessageType.getHandler())));
Thread thread = new Thread(() -> {
while (true) {
try {
DelayMessage delayMessage = rBlockingQueue.take();
log.info("redisson-delay-message-queue,consume message = {}", delayMessage);
handlerMap.get(delayMessage.getType()).handle(delayMessage);
} catch (InterruptedException e) {
e.printStackTrace();
ThreadUtil.safeSleep(1000);
afterPropertiesSet();
}
}
});
thread.setDaemon(true);
thread.start();
}
}
代碼中,首先創(chuàng)建了一個Redisson實現(xiàn)的阻塞隊列RBlockingQueue的實例rBlockingQueue,然后又使用該阻塞隊列rBlockingQueue創(chuàng)建了一個延時隊列RDelayedQueue的實例rDelayedQueue,按照前文中的描述,延時消息添加后并不是立即進入到阻塞隊列rBlockingQueue中,而是到達了設(shè)定的延時時間之后才會從延時隊列rDelayedQueue進入到阻塞隊列rBlockingQueue;因此,延時消息的添加由延時隊列rDelayedQueue完成而延時隊列的消費則由阻塞隊列rBlockingQueue完成,注意,這里如果直接對延時隊列rDelayedQueue進行監(jiān)聽,則延時消息剛加入時就會被消費,達不到延時的效果。
相比于Redisson官網(wǎng)文檔延時隊列中給出的代碼示例,這里被包裝隊列使用阻塞隊列RBlockingQueue的好處是rBlockingQueue.take()會一直阻塞直至隊列內(nèi)有可消費延時消息,避免無意義的循環(huán)占用CPU。
測試
單元測試代碼與上一篇文章基本相同,只是將DelayMessageManager的實現(xiàn)換成了RedissonDelayMessageManager
package com.cube.share.delay.manager;
import com.cube.share.base.utils.JacksonUtils;
import com.cube.share.delay.entity.ExecuteTask;
import com.cube.share.delay.entity.QrCode;
import com.cube.share.delay.message.DelayMessage;
import com.cube.share.delay.message.DelayMessageType;
import com.fasterxml.jackson.core.JsonProcessingException;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;
import javax.annotation.Resource;
import java.util.concurrent.TimeUnit;
/**
* @author cube.li
* @date 2021/9/22 17:12
* @description 測試
*/
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
class DelayMessageManagerTest {
@Resource(type = RedissonDelayMessageManager.class)
DelayMessageManager delayMessageManager;
@Test
void add() throws JsonProcessingException {
DelayMessage delayMessage = new DelayMessage();
QrCode qrCode = new QrCode();
qrCode.setConfigId("fadfdaf110");
qrCode.setUrl("http://www.baidu.com");
delayMessage.setBody(JacksonUtils.toJsonString(qrCode));
delayMessage.setType(DelayMessageType.DELETE_QR_CODE);
DelayMessage.DelayMessageProperties properties = new DelayMessage.DelayMessageProperties();
properties.setExpire(10);
properties.setTimeUnit(TimeUnit.SECONDS);
delayMessage.setProperties(properties);
delayMessageManager.add(delayMessage);
DelayMessage delayMessage1 = new DelayMessage();
QrCode qrCode1 = new QrCode();
qrCode1.setConfigId("fadfdaf1405");
qrCode1.setUrl("http://www.baidu.com");
delayMessage1.setBody(JacksonUtils.toJsonString(qrCode1));
delayMessage1.setType(DelayMessageType.DELETE_QR_CODE);
DelayMessage.DelayMessageProperties properties1 = new DelayMessage.DelayMessageProperties();
properties1.setExpire(5);
properties1.setTimeUnit(TimeUnit.SECONDS);
delayMessage1.setProperties(properties1);
delayMessageManager.add(delayMessage1);
DelayMessage delayMessage2 = new DelayMessage();
ExecuteTask task = new ExecuteTask();
task.setId(1L);
delayMessage2.setBody(JacksonUtils.toJsonString(task));
delayMessage2.setType(DelayMessageType.EXECUTE_TASK);
DelayMessage.DelayMessageProperties properties2 = new DelayMessage.DelayMessageProperties();
properties2.setExpire(9);
properties2.setTimeUnit(TimeUnit.SECONDS);
delayMessage2.setProperties(properties2);
delayMessage2.setSerialId(11235813L);
delayMessageManager.add(delayMessage2);
//delayMessageManager.remove(delayMessage2);
}
}
啟動項目,并執(zhí)行單元測試
向延時隊列中加入三條延時分別為5s 9s 10s 的延時消息,單元測試控制臺輸出如下:
2021-10-12 22:26:40.690 INFO 21340 --- [ main] c.c.s.d.m.RedissonDelayMessageManager : redisson-delay-message-queue,add message = DelayMessage(body={"url":"http://www.baidu.com","configId":"fadfdaf110"}, type=DELETE_QR_CODE, serialId=null, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=10))
2021-10-12 22:26:40.693 INFO 21340 --- [ main] c.c.s.d.m.RedissonDelayMessageManager : redisson-delay-message-queue,add message = DelayMessage(body={"url":"http://www.baidu.com","configId":"fadfdaf1405"}, type=DELETE_QR_CODE, serialId=null, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=5))
2021-10-12 22:26:40.698 INFO 21340 --- [ main] c.c.s.d.m.RedissonDelayMessageManager : redisson-delay-message-queue,add message = DelayMessage(body={"id":1}, type=EXECUTE_TASK, serialId=11235813, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=9))
項目的控制臺輸出如下:
2021-10-12 22:26:45.719 INFO 10452 --- [ Thread-11] c.c.s.d.m.RedissonDelayMessageManager : redisson-delay-message-queue,consume message = DelayMessage(body={"url":"http://www.baidu.com","configId":"fadfdaf1405"}, type=DELETE_QR_CODE, serialId=null, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=5))
2021-10-12 22:26:45.719 INFO 10452 --- [ Thread-11] c.c.s.d.h.QrCodeDelayMessageHandler : 二維碼延時消息處理中,message = DelayMessage(body={"url":"http://www.baidu.com","configId":"fadfdaf1405"}, type=DELETE_QR_CODE, serialId=null, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=5))
2021-10-12 22:26:49.719 INFO 10452 --- [ Thread-11] c.c.s.d.m.RedissonDelayMessageManager : redisson-delay-message-queue,consume message = DelayMessage(body={"id":1}, type=EXECUTE_TASK, serialId=11235813, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=9))
2021-10-12 22:26:49.719 INFO 10452 --- [ Thread-11] c.c.s.d.h.ExecuteTaskDelayMessageHandler : 任務(wù)延時消息處理中,message=DelayMessage(body={"id":1}, type=EXECUTE_TASK, serialId=11235813, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=9))
2021-10-12 22:26:50.718 INFO 10452 --- [ Thread-11] c.c.s.d.m.RedissonDelayMessageManager : redisson-delay-message-queue,consume message = DelayMessage(body={"url":"http://www.baidu.com","configId":"fadfdaf110"}, type=DELETE_QR_CODE, serialId=null, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=10))
2021-10-12 22:26:50.719 INFO 10452 --- [ Thread-11] c.c.s.d.h.QrCodeDelayMessageHandler : 二維碼延時消息處理中,message = DelayMessage(body={"url":"http://www.baidu.com","configId":"fadfdaf110"}, type=DELETE_QR_CODE, serialId=null, properties=DelayMessage.DelayMessageProperties(timeUnit=SECONDS, expire=10))
在經(jīng)過5s 9s 10s后,對應(yīng)的消息均成功被消費。
總結(jié)
在上一篇基于RabbitMq延時消息插件實現(xiàn)的延時隊列之后,本文又提供了一種基于Redisson實現(xiàn)的延時隊列,大體上能夠滿足各種業(yè)務(wù)場景的需求;希望大家在寫業(yè)務(wù)代碼時能夠舉一反三,不止于代碼,不止于業(yè)務(wù),才能在程序員的職業(yè)生涯里有更進一步的發(fā)展。
示例代碼