redis主键过期监听

redis主键过期监听，本质就是使用redis的消息推送

编辑redis 配置文件 ，修改为 notify-keyspace-events "Ex"

注册 RedisMessageListenerContainer ，为Redis消息侦听器提供异步行为的容器

容器是必须的

//创建监听时会检查容器是否存在
public KeyspaceEventMessageListener(RedisMessageListenerContainer listenerContainer) {
Assert.notNull(listenerContainer, "RedisMessageListenerContainer to run in must not be null!");
this.listenerContainer = listenerContainer;
}

@Configuration
public class RedisConfigurer  extends CachingConfigurerSupport {

    @Bean
    RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory) {

        RedisMessageListenerContainer container = new RedisMessageListenerContainer();
        container.setConnectionFactory(connectionFactory);
        return container;
    }


}

//创建监听,继承KeyExpirationEventMessageListener ，重写onMessage方法
@Component
public class RedisKeyExpirationListener extends KeyExpirationEventMessageListener {

    public RedisKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {
        super(listenerContainer);
    }

    @Autowired
    private OrderItemService orderItemService;
    private static Logger log = LoggerFactory.getLogger(RedisKeyExpirationListener.class);


    @Override
    public void onMessage(Message message, byte[] pattern) {
    //在这里处理业务，因为时键过期，所以只能拿到键值，不能拿到value
        String expiredKey = message.toString();
        log.info("Redis主键过期监听" + expiredKey);
        if (expiredKey.startsWith("order:")) {
                log.info("Redis主键过期监听符合要求的主键" + expiredKey);
                //Todo取消订单
                orderItemService.updateCannelOrderByTimeOut(expiredKey);
        }
    }
}