使用RedisCacheWriter#clean在线异步地扫描批量删除缓存数据-spring-data-redis

背景

目标

结论先行

以终为始，结果导向

技术方案

具体实现

spring-boot版本

spring-boot-starter-data-redis-2.7.16
spring-data-redis-2.7.16

源代码


import java.nio.charset.StandardCharsets;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;import cn.hutool.core.thread.ThreadFactoryBuilder;
import com.spring.boot.redis.example.model.CacheKey;
import com.spring.boot.redis.example.service.CacheService;
import lombok.extern.slf4j.Slf4j;import org.springframework.data.redis.cache.BatchStrategies;
import org.springframework.data.redis.cache.RedisCacheWriter;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.stereotype.Service;
import org.springframework.util.StopWatch;/*** 缓存服务实现** @author guang.yi* @since 2023/7/30*/
@Slf4j
@Service("cacheService")
public class CacheServiceImpl implements CacheService {/*** 并发开关*/private final ConcurrentMap<String, Boolean> concurrentSwitch = new ConcurrentHashMap<>(16);private final ExecutorService executorService = new ThreadPoolExecutor(1, 1, 5L, TimeUnit.MINUTES,new ArrayBlockingQueue<>(1),new ThreadFactoryBuilder().setNamePrefix("cache-clean-").setDaemon(true).build());private final RedisConnectionFactory redisConnectionFactory;public CacheServiceImpl(RedisConnectionFactory redisConnectionFactory) {this.redisConnectionFactory = redisConnectionFactory;log.info("create CacheServiceImpl");}@Overridepublic boolean cleanCache(CacheKey cacheKey) {String keyPattern = cacheKey.getKeyPattern();// 避免多次重复地操作if (concurrentSwitch.putIfAbsent(keyPattern, Boolean.TRUE) == null) {// 异步地执行executorService.execute(() -> this.clean(cacheKey));return true;}return false;}private void clean(CacheKey cacheKey) {log.info("cleanCache start, cacheKey={}", cacheKey);StopWatch stopWatch = new StopWatch("cleanCache");stopWatch.start();this.clean(cacheKey.getCacheName(), cacheKey.getKeyPattern());stopWatch.stop();log.info("cleanCache end, cacheKey={}, stopWatch={}", cacheKey, stopWatch);}/*** 缓存Redis的历史数据清理* <pre>* 【批量策略】在线异步地扫描批量删除，每批10个key* 先SCAN，再批量DEL* 【执行策略】预发环境，业务低峰时期* </pre>** @see org.springframework.data.redis.cache.RedisCacheWriter#clean* @see org.springframework.data.redis.cache.DefaultRedisCacheWriter#clean*/private void clean(String cacheName, String keyPattern) {// 【批量策略】SCAN，每批10个keyRedisCacheWriter redisCacheWriter = RedisCacheWriter.nonLockingRedisCacheWriter(redisConnectionFactory, BatchStrategies.scan(10));// 先SCAN，再批量DELredisCacheWriter.clean(cacheName, keyPattern.getBytes(StandardCharsets.UTF_8));}}


# .A.1. Core Properties
spring:application:name: redis-spring-boot-starter-example# RedisPropertiesredis:database: 0host: "localhost"port: 6379timeout: 1sconnect-timeout: 300msclient-name: "user-cache-example"
#    client-type: lettuce
#    sentinel:
#      master: ""
#      nodes: "host:port"
#    cluster:
#      nodes: "host:port"
#      max-redirects: 3
#    jedis:
#      pool:
#        enabled: true
#        max-idle: 8
#        min-idle: 0
#        max-active: 8
#        max-wait: 300ms
#        time-between-eviction-runs: 5mlettuce:shutdown-timeout: 100mspool:enabled: truemax-idle: 8min-idle: 0max-active: 8max-wait: -1time-between-eviction-runs: 5m