redis发布和订阅

常用命令如下：
subscribe channel [channel …]：订阅一个或多个频道
psubscribe pattern [pattern …]：订阅一个或多个符合给定模式的频道，频道名称中包含匹配符 *
unsubscribe [channel [channel …]]：退订频道
punsubscribe [pattern [pattern …]]：退订所有给定模式的频道
publish channel message：将消息发送给指定频道
pubsub subcommand [argument [argument …]]：查看发布与订阅系统状态

session A订阅消息

(session A)127.0.0.1:6379> subscribe new.it
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "new.it"
3) (integer) 1

session B发布消息

(session B)127.0.0.1:6379> publish new hello
(integer) 0

session A收到消息

(session A)127.0.0.1:6379> subscribe new.it
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "new.it"
3) (integer) 1
//以下为收到的消息
1) "message"
2) "new.it"
3) "hello"