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Workloads

Multiplayer

An actor holds a room's shared state and broadcasts events to every connected client.

Prefer to read code? Clone the example repository. View on GitHub

Example generated code

import { Hono } from "hono";
import { actor, event, setup } from "rivetkit";

type Position = { x: number; y: number };

// One actor per room. State is shared by every connected client.
const room = actor({
	state: { players: {} as Record<string, Position> },
	events: { changed: event() },
	actions: {
		join(c, player: string) {
			c.state.players[player] ??= { x: 0, y: 0 };
			c.broadcast("changed", c.state.players);
			return c.state.players;
		},
		move(c, player: string, x: number, y: number) {
			c.state.players[player] = { x, y };
			c.broadcast("changed", c.state.players);
			return c.state.players;
		},
	},
});

export const registry = setup({ use: { room } });

const app = new Hono();
app.all("/api/rivet/*", (c) => registry.handler(c.req.raw));
app.get("/", (c) =>
	c.json({ message: "Use the RivetKit client to join a room." }),
);

export default app;

Deploy and connect

Deploy the app, then connect to its actors from your own system:

const client = createClient<typeof registry>({
	endpoint: deployment.endpoint,
	namespace: deployment.namespace,
	poolName: deployment.pool,
	token: deployment.token,
});

// Open a realtime connection and receive every broadcast from the room.
const room = client.room.getOrCreate(["lobby"]).connect();
room.on("changed", (players) => console.log("players", players));

await room.join("alice");
await room.move("alice", 4, 8);
await room.dispose();

Dynamic Apps does not wrap RivetKit’s action, event, or connection APIs. See Events and Connections in Rivet Actors.