<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.12.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.homeey</groupId>
<artifactId>redis-delay-queue</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>redis-delay-queue</name>
<description>redis-delay-queue</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.redisson/redisson -->
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson-spring-boot-starter</artifactId>
<version>3.19.3</version>
</dependency>
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson-spring-data-23</artifactId>
<version>3.19.3</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>사용 구성 [가장 쉬움]
두 번째: 별도의 redisson 구성 파일 사용
세 번째: spring.redis.redisson을 사용하여 구성 키 아래 구성
자세한 통합을 보려면 springboot 통합 redisson 구성
spring:
redis:
database: 0
host: localhost
port: 6379
timeout: 10000
lettuce:
pool:
max-active: 8
max-wait: -1
min-idle: 0
max-idle: 8package com.homeey.redisdelayqueue.delay;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RBlockingQueue;
import org.redisson.api.RDelayedQueue;
import org.redisson.api.RedissonClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
/**
* 明天的你会因今天到的努力而幸运
*
* @author jt4mrg@qq.com
* 23:11 2023-02-19 2023
**/
@Slf4j
@Component
@RequiredArgsConstructor
public class RedissonDelayQueue {
private final RDelayedQueue<String> delayedQueue;
private final RBlockingQueue<String> blockingQueue;
@PostConstruct
public void init() {
ExecutorService executorService = Executors.newFixedThreadPool(1);
executorService.submit(() -> {
while (true) {
try {
String task = blockingQueue.take();
log.info("rev delay task:{}", task);
} catch (Exception e) {
log.error("occur error", e);
}
}
});
}
public void offerTask(String task, long seconds) {
log.info("add delay task:{},delay time:{}s", task, seconds);
delayedQueue.offer(task, seconds, TimeUnit.SECONDS);
}
@Configuration
static class RedissonDelayQueueConfigure {
@Bean
public RBlockingQueue<String> blockingQueue(RedissonClient redissonClient) {
return redissonClient.getBlockingQueue("TOKEN-RENEWAL");
}
@Bean
public RDelayedQueue<String> delayedQueue(RBlockingQueue<String> blockingQueue,
RedissonClient redissonClient) {
return redissonClient.getDelayedQueue(blockingQueue);
}
}
}실행 효과
RedissonDelayedQueue 구현에서 네 가지 역할이 있음을 알 수 있습니다
RedissonDelayedQueue实现中我们看到有四个角色
redisson_delay_queue_timeout:xxx，sorted set数据类型，存放所有延迟任务，按照延迟任务的到期时间戳（提交任务时的时间戳 + 延迟时间）来排序的，所以列表的最前面的第一个元素就是整个延迟队列中最早要被执行的任务，这个概念很重要
redisson_delay_queue:xxx，list数据类型，暂时没发现什么用，只是在提交任务时会写入这里面，队列转移时又会删除里面的元素
xxx：list数据类型，被称为目标队列，这个里面存放的任务都是已经到了延迟时间的，可以被消费者获取的任务，所以上面demo中的RBlockingQueue的take方法是从这个目标队列中获取到任务的
redisson_delay_queue_channel:xxx，是一个channel，用来通知客户端开启一个延迟任务
RedissonDelayedQueue延迟队列创建时，指定了队列转移服务，以及实现延迟队列的四个重要校色的key。核心代码是指定队列转移任务
QueueTransferTask task = new QueueTransferTask(commandExecutor.getConnectionManager()) {
@Override
protected RFuture<Long> pushTaskAsync() {
return commandExecutor.evalWriteAsync(getRawName(), LongCodec.INSTANCE, RedisCommands.EVAL_LONG,
"local expiredValues = redis.call('zrangebyscore', KEYS[2], 0, ARGV[1], 'limit', 0, ARGV[2]); "//拿到zset中过期的值列表
+ "if #expiredValues > 0 then " //如果有
+ "for i, v in ipairs(expiredValues) do "
+ "local randomId, value = struct.unpack('dLc0', v);"//解构消息，在提交任务时打包的消息
+ "redis.call('rpush', KEYS[1], value);" //放入无前缀的list 队头
+ "redis.call('lrem', KEYS[3], 1, v);"//移除带前缀list 队尾元素
+ "end; "
+ "redis.call('zrem', KEYS[2], unpack(expiredValues));" //移除zset中本次读取的过期元素
+ "end; "
// get startTime from scheduler queue head task
+ "local v = redis.call('zrange', KEYS[2], 0, 0, 'WITHSCORES'); "//取zset最小分值的元素
+ "if v[1] ~= nil then "
+ "return v[2]; " //返回分值，即过期时间
+ "end "
+ "return nil;",
Arrays.asList(getRawName(), timeoutSetName, queueName),
System.currentTimeMillis(), 100);
}
@Override
protected RTopic getTopic() {
return RedissonTopic.createRaw(LongCodec.INSTANCE, commandExecutor, channelName);
}
};
核心代码RedissonDelayedQueue#offerAsync
RedissonDelayedQueue지연 대기열이 생성되면 대기열 전송 서비스와 지연 대기열에 대한 4가지 중요한 색상 보정 키가 지정됩니다. 핵심 코드는 대기열 전송 작업🎜 return commandExecutor.evalWriteNoRetryAsync(getRawName(), codec, RedisCommands.EVAL_VOID,
"local value = struct.pack('dLc0', tonumber(ARGV[2]), string.len(ARGV[3]), ARGV[3]);" //打包消息体：消息id，消息长度，消息值
+ "redis.call('zadd', KEYS[2], ARGV[1], value);"//zset中加入消息及其超时分值
+ "redis.call('rpush', KEYS[3], value);" //向带前缀的list中添加消息
// if new object added to queue head when publish its startTime
// to all scheduler workers
+ "local v = redis.call('zrange', KEYS[2], 0, 0); "//取出zset中第一个元素
+ "if v[1] == value then " //如果最快过期的元素就是这次发送的消息
+ "redis.call('publish', KEYS[4], ARGV[1]); " //channel中发布一下超时时间
+ "end;",
Arrays.asList(getRawName(), timeoutSetName, queueName, channelName),
timeout, randomId, encode(e));🎜🎜핵심 코드RedissonDelayedQueue#offerAsync🎜rrreee🎜Consumer🎜🎜Consumer는 가장 간단합니다. 접두사 없이 목록에서 직접 BLPOP을 읽습니다🎜위 내용은 Redis가 지연 대기열을 구현하는 방법의 상세 내용입니다. 자세한 내용은 PHP 중국어 웹사이트의 기타 관련 기사를 참조하세요!
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