NodeJS Array not filling up - node.js

Question

Im using mongodb as a database after getting the valuation data which are more then one , i loop inside them and get the offers according to the offres_id , I asure you that the database has data inside and to querys are working correctly in fact if i console log them in each iteration i get this result
{
offre: [
{
_id: new ObjectId("63320bf87123db5691c51392"),
user_id: '63304e44aa63c519d887dac1',
brand: 'HP',
model: 'AZGGH-89855A',
photo: '16642242480661659650294043-bs-5.png',
scan_method: 'manual',
__v: 0
}
],
valuation: {
_id: new ObjectId("63320d39a5677df3cebcbdae"),
user_id: '63304e44aa63c519d887dac1',
offre_id: '63320bf87123db5691c51392',
given_price: '1236',
comment: 'no comment',
__v: 0
}
}
{
offre: [
{
_id: new ObjectId("6334202a8c7e6d90b35ee999"),
user_id: '63304e44aa63c519d887dac1',
brand: 'DELL',
model: 'AZGGH-89855A',
photo: '1664360490280Capture.PNG',
scan_method: 'manual',
__v: 0
}
],
valuation: {
_id: new ObjectId("633420be8c7e6d90b35ee99e"),
user_id: '63304e44aa63c519d887dac1',
offre_id: '6334202a8c7e6d90b35ee999',
__v: 0
}
}
but when i try storing each offre & valuation at the same array cell and return it i get this as a result
[]
However this is the code
router.get('/get', async (req, res) => {
try {
Valuation.find({ user_id: req.session.userID })
.exec()
.then(valuation => {
let myData = [];
if (valuation) {
for (let i = 0; i < valuation.length; i++) {
Offre.find({_id : valuation[i].offre_id})
.exec()
.then(offre=>{
myData.push({offre : offre, valuation : valuation[i]})
})
}
res.status(200).json(myData)
} else {
res.status(404).json('no valuations found')
}
})
.catch(error => {
res.status(500).json(error.message)
})
} catch (error) {
res.status(500).json({ error: error.message })
}
})

Answer 1

Since you're already using async, it would be a shame to not use await to simplify your code:
router.get("/get", async (req, res) => {
try {
const valuation = await Valuation.find({ user_id: req.session.userID }).exec();
if (valuation) {
let myData = [];
for (let i = 0; i < valuation.length; i++) {
const offre = await Offre.find({ _id: valuation[i].offre_id }).exec();
myData.push({ offre: offre, valuation: valuation[i] });
}
res.status(200).json(myData);
} else {
res.status(404).json("no valuations found");
}
} catch (error) {
res.status(500).json({ error: error.message });
}
});
You can probably also speed up the Offre query by using an $in query to retrieve all offres with one query, but that's another thing.