understanding official documentation of socket middleware

Question

under this section: https://socket.io/docs/v4/server-socket-instance/#socket-middlewares

while trying to run the sample code in my local machine, the provided sample simply does not works. below are the code used for testing:

namespaceSocket.on("connection", (socket) => {
    console.log("a client has connected")
    socket.use(([event, ...args], next) => {
        if (true) {
            return next(new Error("unauthorized event"));
        }
        // do not forget to call next
        next();
    });

    socket.on("error", (err) => {
        if (err && err.message === "unauthorized event") {
            console.log("unauthorized")
            socket.disconnect();
        }
    });
});

given the sample, I expected that all socket will trigger error and get disconnected whenever its connected, but the middleware section is ignored

after trying to debug it with a simpler sample

const log = (msg: string) => (socket, next) => {console.log(msg);next()}

namespaceSocket.use(log("namespace socket middleware")) //this is logged

namespaceSocket.on("connection", (socket) => {
    socket.use(log("connected socket middleware")) // this is NOT logged
    console.log("a user connected") //this is logged
});

the result is that the middleware outside of connections events does trigger but the middleware inside a successful connections is never triggered.

I also cant tell whether I have missed some configuration which made my local test not behave as documented, so i hope someone can gives me pointer on what is going on

understanding official documentation of socket middleware

0 Answers0