Redis密钥空间通知到期未触发

Question

我正在查看此页面：https://redis.io/topics/notifications

我在配置文件中设置了以下行：

notify-keyspace-events "Kx"

执行此操作（然后运行最终会使某些密钥过期的应用程序）时，我看不到任何事件：

redis-cli --csv psubscribe '__keyspace*__:*expire*'

但是，当我将配置设置为此时：

notify-keyspace-events "Kg"

然后运行相同的应用程序和redis-cli命令，我确实看到了事件：

"pmessage","__keyspace*__:*expire*","__keyspace@0__:spring:session:wca:sessions:expires:9d73fefc-459d-4bf4-83ef-b8fcbf06b997","expire"
"pmessage","__keyspace*__:*expire*","__keyspace@0__:spring:session:wca:sessions:expires:9d73fefc-459d-4bf4-83ef-b8fcbf06b997","expire"
"pmessage","__keyspace*__:*expire*","__keyspace@0__:spring:session:idp:sessions:expires:52dbe449-4616-41ef-bfa6-1d7a16a89f8a","expire"
"pmessage","__keyspace*__:*expire*","__keyspace@0__:spring:session:idp:sessions:expires:52dbe449-4616-41ef-bfa6-1d7a16a89f8a","expire"
"pmessage","__keyspace*__:*expire*","__keyspace@0__:spring:session:idp:sessions:expires:52dbe449-4616-41ef-bfa6-1d7a16a89f8a","expire"
"pmessage","__keyspace*__:*expire*","__keyspace@0__:spring:session:idp:sessions:expires:52dbe449-4616-41ef-bfa6-1d7a16a89f8a","expire"

我了解到TTL过期后，到期不一定正确。但是我不确定这能解释我所看到的内容-我的redis-cli仅查找“过期”事件，并且在（且仅当）通知通用命令时始终看到它们。这对于我的应用来说实在太闲谈了我只想看看过期。

感谢您的帮助。谢谢！

Answer 1

您订阅了错误的频道。

有两种通知：

• 键空间通知：频道为__keyspace@<db>__:<key>
• 关键事件通知：频道为__keyevent@<db>__:<event>

如果要获取所有过期的密钥通知，则有两种选择：

使用键空间通知

1. 启用密钥空间通知：config set notify-keyspace-events Kx

2. 订阅频道：psubscribe __keyspace@*__:*

使用按键事件通知

1. 启用键事件通知：config set notify-keyspace-events Ex

2. 订阅频道：psubscribe __keyevent@*__:expired

Answer 2

您需要订阅“ __keyevent@0__:expired”而不是“ __keyevent@0__:expire”

127.0.0.1:6379> subscribe __keyevent@0__:expired
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "__keyevent@0__:expired"
3) (integer) 1

1) "message"
2) "__keyevent@0__:expired"
3) "mykey"

请参阅此文档。我也面临着同样的问题。我尝试了通过该链接有效的解决方案https://github.com/redis/redis/issues/1855