Subscripbe the request topic: from/+/rpc/to/{ServerId}

The ServerId is the rpc-server own client-id of mqtt.

The + will match any client-id of rpc-client. You can resolve the rpc caller identifier from it while the server received a message.

After processing, publish the result to response topic: from/{ServerId}/rpc_response/to/{ClientId}

Topic: $share/{ClusterId}/from/+/rpc/to/{ClusterId}

The ClusterId should be a valid identifier that used to identify a cluster.

The + is same as #Unicast

Response topic is also same as #Unicast

Anycast Topic: from/+/rpc

It's a broadcast call to any exists session of client. (We recommend always working around session instead of connection. For more about session please reference MQTTv5)

Grouped Multicast Topic: from/+/rpc/to/{GroupId}

Other things about topic are same as #Unicast.

Publish call request to from/{ClientId}/rpc for anycast, or from/{ClientId}/rpc/to/{target} for specific target.

The {ClientId is the rpc-client The {target} should be an id of server, cluster or multicast-group.

Subscribe from/+/rpc_response/to/{ClientId} for getting response.

A Client called Node01 and server called Node02.

Request topic: from/Node01/rpc/to/Node02

Response topic: from/Node02/rpc_response/to/Node01