Fasteer Websockets

Websockets in Fasteer.js.

Getting started

The fastify-websocket plugin is already registered, there is no need to register it manually. If you want to pass options to it, pass them inside the fastifyWebsocket property:

app.plugin(
  fasteerWebsockets({
    fastifyWebsocket: {
      // fastify websockets
    },
  })
);

Shorthand route

Fasteer adds a ws (and websocket as an alias) function to FastifyInstance - it's a shorthand function for defining WebSocket routes. The signature is:

function ws(
  path: string,
  middlewares?: WebsocketMiddleware | WebsocketMiddleware[],
  opts?: WebsocketRouteOptions,
  handler: (conn: SocketStream, req: FastifyRequest) => any
): FastifyInstance;

Middlewares

Middlewares are executed before the route handler and can end the connection by passing false as their return value.

Global Middlewares

They can be registered by passing them into globalMiddlewares:

import { fasteerWebsockets, keepAlive } from "@fasteerjs/websockets";

app.plugin(
  fasteerWebsockets({
    // ...
    globalMiddlewares: [
      // middlewares here
      keepAlive,
    ],
  })
);

Per-route Middlewares

They can be registered inside of the shorthand, like so:

import { Fasteer } from "@fasteerjs/fasteer";

const WsController: Fasteer.FCtrl = async app => {
  app.ws("/path", [middleware], async (req, res) => {
    //
  });
};

export default WsController;

Definining Middlewares

Middlewares are just functions with the following signature:

function middleware(
  conn: SocketStream,
  req: FastifyRequest,
  app: FasteerInstance
): Promise<boolean>;

Additionally, there is a legacy way supporting callbacks, but it is not recommended.

function middleware(
  conn: SocketStream,
  req: FastifyRequest,
  app: FasteerInstance,
  done: (result: boolean) => void
): unknown;

Notice how the middleware returns a boolean - if the boolean returned is false, the next middleware won't be called and the connection will be ended.