[FSTDEP014] FastifyDeprecation: You are trying to set/access the default route.

[evshiron]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the issue has not already been raised

Issue

I start a fastify project with websocket today and receive the following warning:

[FSTDEP014] FastifyDeprecation: You are trying to set/access the default route. This property is deprecated. Please, use setNotFoundHandler if you want to custom a 404 handler or the wildcard (*) to match all routes.

The relevant lines of code are:

• https://github.com/fastify/fastify/blob/main/lib/route.js#L91
• https://github.com/fastify/fastify-websocket/blob/master/index.js#L185

Which might require some refactoring to make it disappear.

[tobbe-r]

+1 Experiencing the exact same issue

[RafaelGSS]

That's expected. See fastify/fastify#4480

[jsumners]

Please read the notice and follow the instructions therein.

[Uzlopak]

Probably open an issue in fastify-websocket to take care of the Deprecation warning and tag it with good first issue

[MarianoFacundoArch]

We should fix this to use new methods?

[jsumners]

We should fix this to use new methods?

Yes.

[evshiron]

Thanks for the replies and just to confirm, if I get it right, because the call to deprecated methods happens in fastify/fastify-websocket (this repo), we (actually you, the maintainers) will update it someday, right?

[jsumners]

Yes, this module needs to be updated. It is the community's responsibility to keep the things they use updated. This software is provided as-is.

[climba03003]

Do we need to replace defaut route in this case? I see we drop hijacking error handling already, maybe just drop default route in this case.
cc @airhorns

[mcollina]

I would need to see what tests breaks. Ideally, that's what we would do.

[xtremespb]

What about replacing the default route logic by prehandler?

fastify.addHook("preHandler", (request, reply, done) => {
    if (request[kWs]) {
        handleUpgrade(request, (connection) => {
            noHandle.call(fastify, connection, request);
        });
    }
    done();
});

[climba03003]

What about replacing the default route logic by prehandler?

No, they are not identical. pre-handler will not run for the route that is not exist.
And, we will be upgrading twice if we add a pre-handler.

Removal of default route means when the route is not explicitly defined. No upgrade will be allowed.
Whereas, currently it upgraded and close afterward.

[mcollina]

Would that change the behavior significantly?

[climba03003]

Would that change the behavior significantly?

I believe the impact would be minimal.

Current

sequenceDiagram
    Broswer->>+Server: Initial Connection with WebScoket
    Server->>-Broswer: 101 Switch Protocol
    Broswer->>+Server: Connection Establish
    Server->>-Broswer: Immediate Close
    Broswer->>+Broswer: Handle by .onclose

After removal of default route

sequenceDiagram
    Broswer->>+Server: Initial Connection with WebScoket
    Server->>-Broswer: 404 Not Found
    Broswer->>+Broswer: Handle by .onerror or .onclose

[mcollina]

Seems even better. My guess is that was a relic of some past code.