Redis publish and subscribe

Redis Publish subscribe (pub/sub) It's a message communication mode ： sender (pub) Send a message , subscriber (sub) receive messages

Redis Clients can subscribe to any number of channels

Redis Publish and subscribe to

（1） The client can subscribe to channels, as shown in the figure below

（2） When you post a message to this channel , The message is sent to the subscribing client

Publish subscribe command line practice

（1） Open a client subscription channel1

SUBSCRIBE channel1

（2） Open another client , to channel1 Release the news hello

publish channel1 hello

notes ： Back to 1 Is the number of subscribers

（3） Open the first client to see the sent message

notes ： Published messages are not persistent , If the subscription client does not receive hello, Only messages published after subscription can be received