Remote Spawning of Actors experimental¶
Remote spawning is an extension of the dynamic spawn using run-time type names (see § :ref:`add-custom-actor-type <#add-custom-actor-type>`__). The following example assumes a typed actor handle named calculator
with an actor implementing this messaging interface named “calculator”.
void client(actor_system& system, const config& cfg) {
auto node = system.middleman().connect(cfg.host, cfg.port);
if (!node) {
cerr << "*** connect failed: "
<< system.render(node.error()) << endl;
return;
}
auto type = "calculator"; // type of the actor we wish to spawn
auto args = make_message(); // arguments to construct the actor
auto tout = std::chrono::seconds(30); // wait no longer than 30s
auto worker = system.middleman().remote_spawn<calculator>(*node, type,
args, tout);
if (!worker) {
cerr << "*** remote spawn failed: "
<< system.render(worker.error()) << endl;
return;
}
// start using worker in main loop
client_repl(make_function_view(*worker));
We first connect to a CAF node with middleman().connect(host, port)
. On success, connect
returns the node ID we need for remote_spawn
. This requires the server to open a port with middleman().open(port)
or middleman().publish(..., port)
. Alternatively, we can obtain the node ID from an already existing remote actor handle—returned from remote_actor
for example—via hdl->node()
. After connecting to the server, we can use middleman().remote_spawn<...>(...)
to create actors remotely.