一、开启Redis key过期提醒
方式二：修改配置文件
redis.conf# 默认 notify-keyspace-events "" notify-keyspace-events Ex方式二：命令行开启
CONFIG SET notify-keyspace-events Ex CONFIG GET notify-keyspace-events
二、notify-keyspace-events
notify-keyspace-events 选项的默认值为空
notify-keyspace-events 的参数可以是以下字符的任意组合， 它指定了服务器该发送哪些类型的通知。
三、Coding
初始化一个
Spring Boot项目pom.xml<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> </dependencies>定义配置类
RedisListenerConfig@Configuration public class RedisListenerConfig { @Bean RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory) { RedisMessageListenerContainer container = new RedisMessageListenerContainer(); container.setConnectionFactory(connectionFactory); return container; } }定义数据生产类
ProviderDataToRedis@Slf4j @Component public class ProviderDataToRedis implements CommandLineRunner { @Autowired private StringRedisTemplate stringRedisTemplate; @Override public void run(String... args) throws Exception { int[] num = new int[]{1}; Random random = new Random(); while (true) { int max = random.nextInt(5); IntStream.range(0, max).forEach(n -> stringRedisTemplate.opsForValue().set(String.format("mq:s1:%s", ++num[0]), "已预订", 5, TimeUnit.SECONDS)); log.info("放了 {} 条数据到redis...", max); TimeUnit.SECONDS.sleep(3); } } }定义监听器 实现
KeyExpirationEventMessageListener接口查看源码发现，该接口监听所有db的过期事件
keyevent@*:expired"定义
Status1ExpirationListener监听状态1到期@Slf4j @Component public class Status1ExpirationListener extends KeyExpirationEventMessageListener { public Status1ExpirationListener(RedisMessageListenerContainer listenerContainer) { super(listenerContainer); } @Autowired private StringRedisTemplate stringRedisTemplate; @Override public void onMessage(Message message, byte[] pattern) { // 用户做自己的业务处理即可,注意message.toString()可以获取失效的key String expiredKey = message.toString(); if (expiredKey.startsWith("mq:s1:")) { log.info("-----------------------------------"); log.info(String.format("过期key[%s]", expiredKey)); String newKey = String.format("mq:s2:%s", expiredKey.substring(6)); String newValue = "行程中"; stringRedisTemplate.opsForValue().set(newKey, newValue, 3, TimeUnit.SECONDS); log.info(String.format("%s: %s", newKey, newValue)); log.info("-----------------------------------"); } } }定义
Status2ExpirationListener监听状态2到期@Slf4j @Component public class Status2ExpirationListener extends KeyExpirationEventMessageListener { public Status2ExpirationListener(RedisMessageListenerContainer listenerContainer) { super(listenerContainer); } @Override public void onMessage(Message message, byte[] pattern) { // 用户做自己的业务处理即可,注意message.toString()可以获取失效的key String expiredKey = message.toString(); if (expiredKey.startsWith("mq:s2:")) { log.info("***********************************"); log.info(String.format("过期key[%s]", expiredKey)); log.info("[{}]行程已完成，修改数据库状态。", newKey); log.info("***********************************"); } } }
四、测试输出
...
2021-01-25 23:16:58.012 INFO 55511 --- [ main] n.y.tools.listener.ProviderDataToRedis : 放了 4 条数据到redis...
2021-01-25 23:17:00.037 INFO 55511 --- [ container-1070] c.i.r.l.Status1ExpirationListener : -----------------------------------
2021-01-25 23:17:00.037 INFO 55511 --- [ container-1070] c.i.r.l.Status1ExpirationListener : 过期key[mq:s1:272]
2021-01-25 23:17:00.037 INFO 55511 --- [ container-1072] c.i.r.l.Status1ExpirationListener : -----------------------------------
2021-01-25 23:17:00.037 INFO 55511 --- [ container-1072] c.i.r.l.Status1ExpirationListener : 过期key[mq:s1:271]
2021-01-25 23:17:00.039 INFO 55511 --- [ container-1070] c.i.r.l.Status1ExpirationListener : mq:s2:272: 行程中
2021-01-25 23:17:00.039 INFO 55511 --- [ container-1072] c.i.r.l.Status1ExpirationListener : mq:s2:271: 行程中
2021-01-25 23:17:00.039 INFO 55511 --- [ container-1070] c.i.r.l.Status1ExpirationListener : -----------------------------------
2021-01-25 23:17:00.039 INFO 55511 --- [ container-1072] c.i.r.l.Status1ExpirationListener : -----------------------------------
2021-01-25 23:17:00.140 INFO 55511 --- [ container-1075] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.140 INFO 55511 --- [ container-1075] c.i.r.l.Status2ExpirationListener : 过期key[mq:s2:270]
2021-01-25 23:17:00.140 INFO 55511 --- [ container-1075] c.i.r.l.Status2ExpirationListener : [270]行程已完成，修改数据库状态。
2021-01-25 23:17:00.140 INFO 55511 --- [ container-1075] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1077] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1077] c.i.r.l.Status2ExpirationListener : 过期key[mq:s2:269]
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1079] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1079] c.i.r.l.Status2ExpirationListener : 过期key[mq:s2:268]
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1077] c.i.r.l.Status2ExpirationListener : [269]行程已完成，修改数据库状态。
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1077] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1079] c.i.r.l.Status2ExpirationListener : [268]行程已完成，修改数据库状态。
2021-01-25 23:17:00.242 INFO 55511 --- [ container-1079] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.546 INFO 55511 --- [ container-1081] c.i.r.l.Status2ExpirationListener : ***********************************
2021-01-25 23:17:00.546 INFO 55511 --- [ container-1081] c.i.r.l.Status2ExpirationListener : 过期key[mq:s2:267]
2021-01-25 23:17:00.546 INFO 55511 --- [ container-1081] c.i.r.l.Status2ExpirationListener : [267]行程已完成，修改数据库状态。
2021-01-25 23:17:00.546 INFO 55511 --- [ container-1081] c.i.r.l.Status2ExpirationListener : ***********************************
...
五、一直增加的线程数
从测试输出的日志中可以看出，线程一直在增加，这个问题还有待解决！