ssubscribe.3valkey - Man Page
Listens for messages published to shard channels.
Synopsis
SSUBSCRIBE shardchannel [shardchannel...]
Description
Subscribes the client to the specified shard channels.
In a Valkey 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 valkey-pubsub(7) Sharded Pub/Sub.
Reply
Resp2
When successful, this command doesn’t return anything. Instead, for each shard channel, one message with the first element being the string ssubscribe is pushed as a confirmation that the command succeeded. Note that this command can also return a -MOVED redirect.
Resp3
When successful, this command doesn’t return anything. Instead, for each shard channel, one message with the first element being the string `ssubscribe' is pushed as a confirmation that the command succeeded. Note that this command can also return a -MOVED redirect.
Complexity
O(N) where N is the number of shard channels to subscribe to.
Acl Categories
@pubsub @slow
History
- Available since: 7.0.0
Examples
> ssubscribe orders Reading messages... (press Ctrl-C to quit) 1) "ssubscribe" 2) "orders" 3) (integer) 1 1) "smessage" 2) "orders" 3) "hello"
See Also
psubscribe(3valkey), publish(3valkey), pubsub(3valkey), pubsub-channels(3valkey), pubsub-help(3valkey), pubsub-numpat(3valkey), pubsub-numsub(3valkey), pubsub-shardchannels(3valkey), pubsub-shardnumsub(3valkey), punsubscribe(3valkey), spublish(3valkey), subscribe(3valkey), sunsubscribe(3valkey), unsubscribe(3valkey)