Basic Lobby Walkthrough¶

The repository's complete, compiling lobby example connects to a Signal Fish server, joins a room, reacts to lobby events, and shuts down cleanly. This page explains that flow without duplicating its source.

Source: examples/basic_lobby.rs

Protocol v2 relay

The example uses the default protocol-v2 relay configuration. Get this path working before choosing protocol v3 or WebRTC mesh.

Run it¶

From a repository checkout:

Bash

cargo run --example basic_lobby

The default server URL is ws://localhost:3536/v2/ws. Override it when your server runs elsewhere:

Bash

SIGNAL_FISH_URL=ws://my-server:3536/v2/ws cargo run --example basic_lobby

Need a server? The Signal Fish Server five-minute quick start provides a development setup.

What the example does¶

1. Connect and start¶

Rust

tracing::info!("connecting…");
let transport = WebSocketTransport::connect(&url).await?;
let config = SignalFishConfig::new("mb_app_abc123");
let (mut client, mut events) = SignalFishClient::start(transport, config);

The App ID is a public application label, not a secret. An open development server accepts a test label; a managed or production server may restrict the allowed labels.

Starting the client queues authentication and returns a command handle plus an event receiver. Keep receiving events while the client is active.

2. Wait for authentication¶

Rust

SignalFishEvent::Authenticated { app_name, .. } => {
    let params = JoinRoomParams::new("example-game", "RustPlayer")
        .with_max_players(4);
    client.join_room(params)?;
}

Room commands are valid only after Authenticated. Authentication failures arrive as AuthenticationError; the example logs the server error code and exits.

3. Join and become ready¶

Rust

SignalFishEvent::RoomJoined { room_code, .. } => {
    tracing::info!("joined room {room_code}");
    client.set_ready()?;
}

The example also reports players joining or leaving and observes LobbyStateChanged. When everyone is ready, it sends one start_game() request.

4. Handle connection state¶

The event loop reports Connected, errors, and disconnects. It also keeps the authority/start-request state correct if a Reconnected event arrives. The example exits on Disconnected; it does not initiate a reconnect itself.

5. Shut down¶

Rust

client.shutdown().await;

Pressing Ctrl+C leaves the event loop and asks the transport to close cleanly. Shutdown waits up to SignalFishConfig::shutdown_timeout, then uses the transport abort path if needed.

Advanced examples¶

After the lobby flow works, use these compiling repository examples with the canonical guide for that subsystem:

custom_transport.rs with the custom transport guide
mesh_session.rs with the mesh guide
load_lab.rs with the delivery and backpressure guide
the complete tests/godot-web-smoke fixture with the Godot and WebAssembly guide

The focused guides own platform setup and protocol contracts so those details have one maintained source of truth.