intercepting PUT routes on /resources and forwarding internally to /resources/:id

I want to mock a backend with a PUT API slightly different from the standard PUT /resources/:id.

I found a working ugly solution by intercepting my '/tasks', extracting the id from the JSON body and redirecting to '/tasks/:id'.

With:

server.put('/tasks/', (req, res, next) => {
    res.redirect(302, 'http://localhost:3300/tasks/' + req.body.id);
});

But how to do it cleanly ? How to forward internally to the standard json-server processing for /tasks/:id without redirecting ?