Server API » Graceful Shutdown

Colyseus provides a graceful shutting down mechanism by default. These actions will be performed before the process kill itself:

• Disconnect all connected clients asynchronously (Room#onLeave)
• Dispose all spawned rooms asynchronously (Room#onDispose)
• Perform optional asynchronous callback before shutting down the process Server#onShutdown

If you're performing async tasks on onLeave / onDispose, you should return a Promise, and resolve it when the task is ready. The same applies to onShutdown(callback).

Returning a Promise

By returning a Promise, the server will wait for them to be completed before killing the worker process.

import { Room } from "colyseus";

class MyRoom extends Room {
    onLeave (client) {
        return new Promise((resolve, reject) => {
            doDatabaseOperation((err, data) => {
                if (err) {
                    reject(err);
                } else {
                    resolve(data);
                }
            });
        });
    }

    onDispose () {
        return new Promise((resolve, reject) => {
            doDatabaseOperation((err, data) => {
                if (err) {
                    reject(err);
                } else {
                    resolve(data);
                }
            });
        });
    }
}

Using async

The async keyword will make your function return a Promise under the hood. Read more about Async / Await.

import { Room } from "colyseus";

class MyRoom extends Room {
    async onLeave (client) {
        await doDatabaseOperation(client);
    }

    async onDispose () {
        await removeRoomFromDatabase();
    }
}

Process shutdown callback

You can also listen for process shutdown by setting a onShutdown callback.

import { Server } from "colyseus";

let server = new Server();

server.onShutdown(function () {
    console.log("master process is being shut down!");
});