SSUBSCRIBE
Syntax
SSUBSCRIBE shardchannel [shardchannel ...]
- Available since:
- 7.0.0
- Time complexity:
- O(N) where N is the number of shard channels to subscribe to.
- ACL categories:
-
@pubsub
,@slow
,
Subscribes the client to the specified shard channels.
In a Redis cluster, shard channels are assigned to slots by the same algorithm used to assign keys to slots.
Client(s) can subscribe to a node covering a slot (primary/replica) to receive the messages published.
All the specified shard channels needs to belong to a single slot to subscribe in a given SSUBSCRIBE
call,
A client can subscribe to channels across different slots over separate SSUBSCRIBE
call.
For more information about sharded Pub/Sub, see Sharded Pub/Sub.
Examples
> ssubscribe orders
Reading messages... (press Ctrl-C to quit)
1) "ssubscribe"
2) "orders"
3) (integer) 1
1) "smessage"
2) "orders"
3) "hello"
RESP2 Reply
When successful, this command doesn't return anything. Instead, for each shard channel, one message with the first element being the stringssubscribe
is pushed as a confirmation that the command succeeded. Note that this command can also return a -MOVED redirect.