i have a problem in my code: idols.js

router.post(
'/creating',

check('name', 'Min 1 and Max 50!').isLength({ min: 1, max: 50 }),

(req, res) => {
  
  const errors = validationResult(req);
  if (!errors.isEmpty()) {      
    alertError = errors.array();
    res.render('idols/create', {alertError});      
  }
  else {  
    //Next if value is good
  }      
});

and idolsController.js

const idols = require('../models/idols'); 
class idolsController {

creating(req, res, next) {
    const idols_data = new idols(req.body);
    idols_data.save()
            .then(() => res.redirect('/idols/edit'))
            .catch(next());
}
module.exports = new idolsController;

my idols.js when not using logic validation

router.post('/creating', idolsController.creating); 

--- My question: I want to convert the code in the 3rd paragraph to the code in the 1st paragraph (in this topic) thank for reading.