NakamaMultiplayerBridge with Authoritative

[rafadsm]

Im using Godot 4.0.1 stable with addon from branch 4.0
Im trying to use High-level Multiplayer API with Nakama server match
I did a .lua in data/modules to create a match, some part of lua contents:

local function match_create(context, _payload)
    local match_id = nk.match_create("main", {})
    return match_id
end
nk.register_rpc(match_create, "match.create")

in godot after login and socket is connected, i did like in README.md
https://github.com/heroiclabs/nakama-godot/blob/master/README.md?plain=1#L172

var mat = await nakama_client.rpc_async(nakama_session, "match.create")

multiplayer_bridge = NakamaMultiplayerBridge.new(nakama_socket)
multiplayer_bridge.match_join_error.connect(self._on_match_join_error)
multiplayer_bridge.match_joined.connect(self._on_match_joined)
get_tree().get_multiplayer().set_multiplayer_peer(multiplayer_bridge.multiplayer_peer)
get_tree().get_multiplayer().peer_connected.connect(self._on_peer_connected)
get_tree().get_multiplayer().peer_disconnected.connect(self._on_peer_disconnected)
await multiplayer_bridge.join_match(mat.payload)

but the events is never triggered and my get_tree().get_multiplayer().get_unique_id() always is 0
In console (server side), im in the match and the match is running, when i connect second client, still not working or no feedback, rpc's not working too and console shows has 2 clients in the match
When i use multiplayer_bridge.create_match(), works perfectly but the match is not Nakama Authoritative and my client is the host

Is there any way to make it work with Nakama Authoritative?

[novabyte]

@316902108 The Godot 4 support was completed about 4 weeks ago but is on master branch rather than a release right now. If you encounter bugs you're welcome to submit a pull request which we'd be happy to review, merge, and provide attribution on. 👍

[dsnopek]

Hm. Unfortunately, I don't think NakamaMultiplayerBridge will currently work with an authoritative match.

NakamaMultiplayerBridge.join_match() is assuming that there is a host already connected to the match, which is responsible for allocating the peer ids. Normally, one player's client would call NakamaMultiplayerBridge.create_match() which would make them the host, or if the match is created via NakamaMultiplayerBridge.start_matchmaking() the host is selected automatically.

For authoritative matches to work, there would be a few pre-requistes:

1. The developer would need to setup a "match handler" in Nakama per these docs: https://heroiclabs.com/docs/nakama/concepts/multiplayer/authoritative/
2. Unlike relayed multiplayer, authoritative multiplayer won't automatically relay messages to other players. NakamaMultiplayerBridge depends on the messages being relayed, so your match handler code would need to be setup to relay those messages
3. We'd need to add a new method to NakamaMultiplayerBridge, like, NakamaMultiplayerBridge.join_as_host() for one player to join as the host, or maybe NakamaMultiplayerBridge.join_authoritative() and have it automatically pick a host similar to how it works with the matchmaker? For the latter, there could maybe be code in the match handler that is responsible for selecting the host?

In any case, I'm not sure what the advantage would be to using an authoritative match with NakamaMultiplayerBridge anyway?

NakamaMultiplayerBridge is simply using Nakama to relay the messages between the peers. These messages are binary data specific to how Godot sends RPCs - Nakama can't really process them in any way. If you really wanted Nakama to be truly authoritative over the match, you'd be better off not using NakamaMultiplayerBridge at all, and instead send custom messages using the normal Nakama API.

[gmjosack]

In any case, I'm not sure what the advantage would be to using an authoritative match with NakamaMultiplayerBridge anyway?

I've been looking into doing this so that I can have an authoritative match so I can use labels make a lobby with functionality like private matches, region info, etc that could be filtered on the client following this guide https://heroiclabs.com/docs/nakama/guides/concepts/lobby/

My plan was to do the lobby and just relay everything else in MatchLoop which is pretty simple, just look for specific opCodes related to the lobby and relay everything else. This mostly works fine by just running the RPC, joining the lobby and calling nakama_bridge._setup_host() except there's a ton of spam errors despite the MultiplayerSyncronizer working fine.

Took me a while to realize what was going on but there's a pretty big issue that makes this really difficult to solve. The nakama bridge relies on being able to send to specific presences, but the MatchLoop isn't passed the target presences so there's no way to know where those messages where meant to go in an authoritative server without encoding the presences into your payload and parsing it on the server.