notFound() / useMethodNotAllowed()

app.notFound(handler?)

Registers a catch-all 404 Not Found middleware. Must be registered after all your routes.

app.notFound();
app.notFound((req, res) => res.status(404).send("Page not found"));

Parameter	Type	Default	Description
handler	RequestHandler	JSON default	Optional custom handler

Returns

KaelumApp — the app instance for chaining.

---

app.useMethodNotAllowed(options?)

Intercepts requests where the path exists, but the HTTP method doesn’t, returning a 405 Method Not Allowed with the Allow header populated with the accepted methods.

Must be registered after your routes and before app.notFound().

app.useMethodNotAllowed();

app.useMethodNotAllowed({
  handler: (req, res, allowedMethods) => {
    res.status(405).json({ allowed: allowedMethods });
  }
});

Parameter	Type	Default	Description
options.handler	Function	JSON default	Optional handler function (req, res, allowedMethods) => void

Returns

KaelumApp — the app instance for chaining.

---

MethodNotAllowedOptions

interface MethodNotAllowedOptions {
  handler?: (req: Request, res: Response, allowedMethods: string[]) => any;
}