当有新消息通过 PUBLISH 命令发送给频道 channel1 时, 这个消息就会被发送给订阅它的三个客户端:
PUBLISH <channel> <message>
publish channel:sports "Tim won the championship"
subscribe channel [channel...]
subscribe channel:sports
publish channel:sports "James lost the championship"
unsubscribe [channel [channel ...]]
psubscribe pattern [pattern...]punsubscribe [pattern [pattern ...]]
psubscribe it*
pubsub channels [pattern]
pubsub numsub [channel ...]
pubsub numpat
subscribe video:changes
publish video:changes "video1,video3,video5"
for video in video1,video3,video5update {video}