rpc_await

Small layer for Godot 4 RPC to allow making rpc-calls or sending messages to peers that you can await on for a return value.

Because sometimes you just want to request something from a client and await the result to continue instead of spreading your code over multiple functions that call each other over different machines.

Documentation

• This readme for a quick overview
• The example scene for a working example
• The code documentation for details

Installation

• Add the addons/rpc-await folder to your project.
• Add rpc_await.gd as an autoload or instantiate it and place in your tree wherever you like.

Usage calling functions

• Use send_rpc or send_rpc_timeout to call a function on the same location in the scene tree of the peer:

var result = RpcAwait.send_rpc(target_net_id, _do_some_work)

• The peer needs to have this function, but no need for the @rpc annotation:

func _do_some_work() -> String:
    await get_tree().create_timer(2).timeout # You can use await on this side, too.
    return "My Answer!"

Usage for messages

• Use send_msg or send_msg_timeout to send arbitrary data to a peer and get a response. This message can also be a Dictionary with msg data or just an int to specify a message type.

var result = await RpcAwait.send_msg(target_net_id, my_data)

• Handle these requests on the peer by connecting to the request_received signal and fill in the result property with your result:

func _ready():
    RpcAwait.message_received.connect(_message_received)

func _message_received(req: RpcAwait.RequestData):
    var my_data = req.data
    [...]
    req.result = my_result

Notes

• The signal handlers of message_received may not use await themselves.
• RpcAwait.default_timeout_secs [default 5.0] can be changed to suit your needs. Values <= 0 disable the timeout.
• Give a custom timeout value for specific calls using send_rpc_timeout and send_msg_timeout variants.