Easy Tutorial
Sorted Sets Zrevrangebyscore Hashes Hget Hyperloglog Pfcount Strings Msetnx Redis Partitioning Connection Select Redis Geo Lists Lset Server Config Resetstat Sets Sismember Lists Brpop Strings Getbit Keys Randomkey Strings Setex Server Client Getname Pub Sub Punsubscribe Strings Incrby Sorted Sets Zincrby Keys Dump Sets Spop Strings Get Strings Psetex Lists Lrange Redis Sets Server Command Getkeys Strings Decr Strings Incr Redis Transactions Lists Lpop Sorted Sets Zrank Keys Pexpireat Scripting Script Load Sorted Sets Zunionstore Scripting Script Exists Hashes Hexists Keys Expireat Sets Sinterstore Keys Del Keys Move Sorted Sets Zscore Lists Llen Server Info Server Debug Object Sorted Sets Zremrangebylex Server Config Rewrite Sets Sdiffstore Pub Sub Subscribe Redis Keys Server Client Pause Strings Strlen Redis Backup Keys Ttl Sorted Sets Zrange Redis Strings Sets Sdiff Hashes Hmget Sorted Sets Zcard Connection Quit Strings Setrange Server Flushall Keys Renamenx Server Config Set Connection Ping Lists Brpoplpush Sets Sinter Server Flushdb Redis Intro Server Client List Keys Type Server Sync Keys Pexpire Sorted Sets Zremrangebyscore Keys Rename Java Environment Setup Transactions Discard Redis Lists Server Client Setname Server Role Hashes Hsetnx Redis Sorted Sets Keys Persist Transactions Watch Lists Ltrim Server Client Kill Strings Getset Sets Smove Lists Lpushx Sorted Sets Zscan Connection Echo Strings Mget Sorted Sets Zlexcount Redis Hyperloglog Sorted Sets Zadd Sets Srandmember Redis Pipelining Transactions Multi Hashes Hdel Hashes Hkeys Pub Sub Psubscribe Keys Exists Sorted Sets Zremrangebyrank Sorted Sets Zrevrange Lists Rpushx Server Debug Segfault Hashes Hvals Server Bgrewriteaof Sets Sscan Strings Mset Keys Pttl Connection Auth Strings Incrbyfloat Keys Expire Sorted Sets Zrangebylex Hashes Hmset Sets Scard Sorted Sets Zrevrank Strings Decrby Server Lastsave Server Cluster Slots Redis Commands Redis Install Server Save Server Config Get Redis Hashes Keys Keys Hashes Hincrbyfloat Redis Data Types Strings Setbit Redis Benchmarks Hyperloglog Pfmerge Sorted Sets Zrem Transactions Exec Server Command Info Pub Sub Unsubscribe Transactions Unwatch Strings Getrange Hashes Hincrby Sorted Sets Zrangebyscore Redis Pub Sub Sets Smembers Lists Lindex Scripting Eval Sets Sadd Hyperloglog Pfadd Lists Lrem Redis Tutorial Server Slowlog Lists Blpop Pub Sub Publish Lists Linsert Scripting Evalsha Sets Sunionstore Redis Conf Server Command Count Sorted Sets Zcount Server Monitor Sorted Sets Zinterstore Server Command Server Dbsize Hashes Hlen Scripting Script Flush Server Slaveof Keys Scan Redis Connection Hashes Hset Redis Server Redis Scripting Lists Rpop Redis Client Connection Scripting Script Kill Redis Security Server Time Strings Append Redis Java Server Showlog Server Shutdown Lists Rpush Lists Rpoplpush Lists Lpush Server Bgsave Sets Srem Strings Setnx Redis Stream Hashes Hscan Redis Php Pub Sub Pubsub Hashes Hgetall Strings Set Sets Sunion
❮ Sorted Sets Zrangebyscore Sets Smembers ❯

Redis Publish Subscribe

Redis Publish Subscribe (pub/sub) is a messaging communication pattern: the sender (pub) sends a message, and the receiver (sub) receives the message.

Redis clients can subscribe to any number of channels.

The diagram below shows the channel channel1, and the relationship between this channel and three clients — client2, client5, and client1:

When a new message is sent to channel1 via the PUBLISH command, this message is sent to the three clients subscribed to it:

Example

The following example demonstrates how publish-subscribe works, requiring two redis-cli clients to be opened.

In our example, we created a subscription channel named tutorialproChat:

First redis-cli Client

redis 127.0.0.1:6379> SUBSCRIBE tutorialproChat

Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "tutorialproChat"
3) (integer) 1

Now, let's reopen another redis client and publish two messages to the same channel tutorialproChat, the subscriber will receive the messages.

Second redis-cli Client

redis 127.0.0.1:6379> PUBLISH tutorialproChat "Redis PUBLISH test"

(integer) 1

redis 127.0.0.1:6379> PUBLISH tutorialproChat "Learn redis by tutorialpro.org"

(integer) 1

# The subscriber's client will display the following messages
1) "message"
2) "tutorialproChat"
3) "Redis PUBLISH test"
1) "message"
2) "tutorialproChat"
3) "Learn redis by tutorialpro.org"

GIF demonstration as follows:

-

Start the local Redis service and open two redis-cli clients.

-

In the first redis-cli client, enter SUBSCRIBE tutorialproChat, meaning to subscribe to the tutorialproChat channel.

-

In the second redis-cli client, enter PUBLISH tutorialproChat "Redis PUBLISH test" to send a message to the tutorialproChat channel, at which point the first redis-cli client will see the test message sent by the second redis-cli client.

Redis Publish Subscribe Commands

The table below lists common Redis publish-subscribe commands:

No. Command and Description
1 PSUBSCRIBE pattern [pattern ...] <br>Subscribe to one or more channels that match the given patterns.
2 PUBSUB subcommand [argument [argument ...]] <br>Check the status of the publish-subscribe system.
3 PUBLISH channel message <br>Send a message to the specified channel.
4 PUNSUBSCRIBE [pattern [pattern ...]] <br>Unsubscribe from all channels that match the given patterns.
5 SUBSCRIBE channel [channel ...] <br>Subscribe to one or more channels.
6 UNSUBSCRIBE [channel [channel ...]] <br>Unsubscribe from the specified channels.
❮ Sorted Sets Zrangebyscore Sets Smembers ❯