Problem with findById to display product detail via their Id - node.js

Question

I am new to nodeJs and wanted to practice creating a shopping cart. I all succeeded alone but managed to display the detail of products clicked by the user that it does not work:
SUMMARY OF MY CODE
I created in my models folder two js files called user.js and jacket.js which each contain a schema and model separately. In my Controllers folder, I have an index.js file which includes:
const User = require ("../models/users")
const Jacket = require ('../models/jacket')
My question is that I want to access the Id of these two documents at the same time: Here is my code
const getProductId = (req, res, next) => {
const id = req.params.id;
const Users = User;
const Jackets = Jacket;
!!!. findById(id, (error, product) => {
if (error) console.log(error);
console.log(product);
res.render("product-detail", {
product: product
});
});
};
module.exports = { getProductId: getProductId };
My routes folder:
const express = require ('express')
const router = express.Router ()
const getIndexController = require ('../controllers/index')
router.get ('/product/:id', getIndexController.getProductId)
THANKS TO ALL

Answer 1

By default mongodb autogenerates ids, so having the same id in two different collections seems unlikely unless you customized the ids.
But anyway... Here is a promise-based solution.
Promise.all([
User.findById(id).exec(),
Jacket.findById(id).exec()
])
.then(([user, jacket]) => {
// Or however your template might look like
res.render('product-detail', { user, jacket } )
})
.catch(error =>{
console.log(error)
})
The key here is that mongo will not wait after it sends a query to the database unless you force it to.
If you insist on using callbacks then you have to chain them:
User.findById (id, (error, user) => {
Jacket.findById (id, (error, jacket) => {
// This is what we call "callback hell"
// It might not seem so bad, but it quickly builds up.

Answer 2

i tried that
const getProductId = (req, res, next) => {
const id = req.params.id Promise.all ([ User.findById (id) .exec (), Jacket.findById
(id) .exec ()])
.then (([product]) => { res.render ('product-detail', {product}) })
.catch (error => { console.log (error) }) }
it only works for User
Here is my code in my ejs file
<h1> <% = product.name%> </h1>
<img width = "200px" height = "200px" src = "<% = product.image%>" alt = "<% =
product.image%>" />
<h1> <% = product.description%> </h1> <h1> <% = product.prix%> </h1>