介绍
Redis 键过期事件是 Redis 中非常有用的功能，可以在键过期时触发事件通知。这对于缓存失效、会话管理、定时任务等场景非常有用。
Redis配置
Redis 默认是没有启用键过期事件通知的，你需要通过配置来启用这个功能。可以通过修改 redis.conf 文件或者使用 CONFIG SET 命令来启用键过期事件通知。
notify-keyspace-events Ex
依赖
<!-- 操作redis-->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
配置文件
spring:redis:host: localhostport: 6379#password: 用的本机的redis，并且我没有设置redis密码database: 0lettuce:pool:# 最大阻塞等待时间，负数表示没有限制max-wait: -1# 连接池中的最大空闲连接max-idle: 5# 连接池中的最小空闲连接min-idle: 0# 连接池中最大连接数，负数表示没有限制
写入键
@RestController
@RequiredArgsConstructor
public class BasicController {private final StringRedisTemplate stringRedisTemplate;@GetMapping("/hello")public String hello() {// 设置键值对，并指定过期时间为 10 秒stringRedisTemplate.opsForValue().set("product:123", "dpc", Duration.ofSeconds(5));// 获取值String str = stringRedisTemplate.opsForValue().get("name");System.out.println("Value: " + str);return str;}
}
配置监听器
@Configuration
public class RedisListenerConfig {@Beanpublic RedisMessageListenerContainer redisMessageListenerContainer(RedisConnectionFactory connectionFactory) {RedisMessageListenerContainer container = new RedisMessageListenerContainer();container.setConnectionFactory(connectionFactory);return container;}@Beanpublic OrderKeyExpirationListener orderKeyExpirationListener(RedisMessageListenerContainer container) {// 配置监听器只监听 `order:*` 键OrderKeyExpirationListener listener = new OrderKeyExpirationListener(container);container.addMessageListener(listener, new ChannelTopic("__keyevent@0__:expired"));return listener;}@Beanpublic SessionKeyExpirationListener sessionKeyExpirationListener(RedisMessageListenerContainer container) {// 配置监听器只监听 `session:*` 键SessionKeyExpirationListener listener = new SessionKeyExpirationListener(container);container.addMessageListener(listener, new ChannelTopic("__keyevent@0__:expired"));return listener;}@Beanpublic ProductKeyExpirationListener productKeyExpirationListener(RedisMessageListenerContainer container) {// 配置监听器只监听 `product:*` 键ProductKeyExpirationListener listener = new ProductKeyExpirationListener(container);container.addMessageListener(listener, new ChannelTopic("__keyevent@0__:expired"));return listener;}}
按KEY监听
监听session键
@Slf4j
public class SessionKeyExpirationListener extends KeyExpirationEventMessageListener {public SessionKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {super(listenerContainer);}@Overridepublic void onMessage(Message message, byte[] pattern) {String key = message.toString();if (key.startsWith("session:")) {log.info("会话【" + key + "】已过期");// 处理会话超时的逻辑}}
}
监听product键
@Slf4j
public class ProductKeyExpirationListener extends KeyExpirationEventMessageListener {public ProductKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {super(listenerContainer);}@Overridepublic void onMessage(Message message, byte[] pattern) {String key = message.toString();if (key.startsWith("product:")) {log.info("产品【" + key + "】已过期");// 处理产品相关的超时逻辑}}
}
监听order键
public class OrderKeyExpirationListener extends KeyExpirationEventMessageListener {public OrderKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {super(listenerContainer);}@Overridepublic void onMessage(Message message, byte[] pattern) {String key = message.toString();System.out.println(123);if (key.startsWith("order:")) {// 处理订单相关的超时逻辑}}
}
