springboot~redis的hash結構爲key設置過期策略

redis配置文件開啓鍵過期

#  The "notify-keyspace-events" takes as argument a string that is composed
#  of zero or multiple characters. The empty string means that notifications
#  are disabled.
#
#  Example: to enable list and generic events, from the point of view of the
#           event name, use:
#
#  notify-keyspace-events Elg
#
#  Example 2: to get the stream of the expired keys subscribing to channel
#             name __keyevent@0__:expired use:
#
#  notify-keyspace-events Ex
#
#  By default all notifications are disabled because most users don't need
#  this feature and the feature has some overhead. Note that if you don't
#  specify at least one of K or E, no events will be delivered.

springboot中實現鍵後的處理邏輯

• 訂閱邏輯

public class KeyExpiredEventMessageListener implements MessageListener {

	private final RedisTemplate redisTemplate;

	public KeyExpiredEventMessageListener(RedisTemplate redisTemplate) {
		this.redisTemplate = redisTemplate;
	}

	@Override
	public void onMessage(Message message, byte[] pattern) {
		String expiredKey = message.toString();
		// 處理鍵過期事件邏輯
		System.out.println("Key expired: " + expiredKey);
		String[] keys = expiredKey.split("\\:");
		redisTemplate.opsForHash().delete(keys[0], keys[1]);
	}

}

• 註冊組件

	@Bean
	public RedisMessageListenerContainer redisMessageListenerContainer(RedisConnectionFactory connectionFactory,
																	   KeyExpiredEventMessageListener keyExpiredEventMessageListener) {
		RedisMessageListenerContainer container = new RedisMessageListenerContainer();
		container.setConnectionFactory(connectionFactory);
		container.addMessageListener(keyExpiredEventMessageListener, new PatternTopic("__keyevent@*__:expired"));//__keyevent@0__:expired  #0代表redis中的db索引
		return container;
	}

	@Bean
	public KeyExpiredEventMessageListener keyExpiredEventMessageListener(RedisTemplate redisTemplate) {
		return new KeyExpiredEventMessageListener(redisTemplate);
	}

• 測試demo

@Test
public void hashsetExpire4() throws InterruptedException {
	redisTemplate.opsForHash().put("h_set4", "a", "1");
	redisTemplate.opsForHash().put("h_set4", "b", "2");
	redisTemplate.opsForValue().set("h_set4:b", "2");
	redisTemplate.expire("h_set4:b", Duration.ofSeconds(10));// 多次設置時，以最後一次爲準，這時有效期重設爲1分
	Thread.sleep(1000 * 60);

}

測試用例中，在10秒後，由於h_set4:b這個鍵過期了，所以觸發了KeyExpiredEventMessageListener事件，最後將對應的hashset裏的鍵被動刪除。