How does routing work in Express?

Question

Node.js

Help with routing in Node.js Express framework.
I am writing an application - a note manager, and at this time there are routings for all CRUD-operations of notes.

app.get('/notes', (req, res)=> {
    db.listNotes().then(data => res.send(data));
});

app.post('/notes', (req, res)=> {
    db.createNote(req.body).then(data => res.send(data));
});

app.delete('/notes/:id', (req, res)=> {
    db.deleteNote(req.params.id).then(data => res.send(data));
});

app.put('notes/:id', (req, res)=> {
   db.updateNote(req.params.id).then(data => res.send(data));
});

These are 4 note-taking functions. And if I need to add the "Users" entity, and then "Themes", will I need to add 4 more functions for each model? Are there any methods for optimizing such tasks? Or should the main entry point to the application contain such monotonous functions?

Answer 1

same functions?

All functions are different for you, move your logic to NotesController.
And do not forget that this is a training example and such a cb will be longer than 1 line.
I advise you to look at what middleware is and how to process errors in express, this immediately hurts the eye

Answer 2

After all, you can put it in a separate function, and do something like:

function crud(app, path, controller) {
    app.get(path, controller.get);
    app.post(path, controller.post);
    app.delete(`${path}/:id`, controller.delete);
    app.put(`${path}/:id`, controller.put);    
}

class NotesController {
    get(req, res) {
        db.listNotes().then(data => res.send(data));
    }

    post(req, res) {
        db.createNote(req.body).then(data => res.send(data));
    }

    delete(req, res) {
        db.deleteNote(req.params.id).then(data => res.send(data));
    }

    put(req, res) {
        db.updateNote(req.params.id).then(data => res.send(data));
    }
}

crud(app, '/notes', new NotesController);
crud(app, '/users', new UsersController);

Answer 3

Uncompromising adherence to the DRY principle:

[
    ['get', '/notes', 'listNotes'],
    ['post', '/notes', 'createNote'],
    ['delete', '/notes/:id', 'deleteNote'],
    ['put', '/notes/:id', 'updateNote'],
].map(([app_method, route, db_method]) => {
    app[app_method](route, (req, res) => {
        db[db_method](req.params.id).then(data => res.send(data));
    });
});

Answer 4

Regular expressions can be used as a route. There is a .any() handler in which you can extract a specific type of request from req (get/post/delete/put). Well, there is app.route() , which can chain handlers into one chain (in combination with regular expressions). app.route().get().post().put().delete()