Mongoose Nested Queries - find and updating two fields in different documents - node.js

Question

What Im trying to do is have one user send an amount to another user, Id like for the amount to be subtracted from the sender's balance, and added to the receiver's balance. The problem is that the receivers balance is updated and works, but the previous query to subtract the amount from the sender isn't working.
I understand there are no joins in mongoose (at least not in the classical sense), so Id need to query the user's balance first and then update it in another query. But surely there is a way to nest these queries? Im hoping I just have the syntax wrong.
user.js
const { Decimal128 } = require("mongodb");
const mongoose = require("mongoose");
const Schema = mongoose.Schema;
const UserSchema = new Schema({
email: {
type: String,
required: true,
},
password: {
type: String,
required: true,
},
name: {
type: String,
required: true,
},
useraddress: {
type: String,
required: true,
},
userbalance: {
type: Decimal128,
required: true,
}
});
module.exports = User = mongoose.model("users", UserSchema);
server.js
app.post("/sendamount", function (req, res) {
var amount = 100;
var senderAddress = "Bob123";
var receiverAddress = req.body.receiver;
// Take amount from sender balance
User.findOne({useraddress:senderAddress}, (err, sub) => {
if (err) return handleError(err);
var mybalance = parseFloat(sub.userbalance)
console.log(mybalance)
User.findOneAndUpdate(
{ useraddress: senderAddress },
{ userbalance: mybalance - amount }),
// send to receiver balance
User.findOne({useraddress:receiverAddress}, (err, sub2) => {
if (err) return handleError(err);
var receiverbalance = parseFloat(sub2.userbalance)
console.log(receiverbalance)
// add amount to receiver's balance
User.findOneAndUpdate(
{ useraddress: receiverAddress },
{ userbalance: receiverbalance + amount },
function (err, data) {
if (err) res.send(err);
res.send(data);
console.log("found " + data)
}
)
})
})
})
Would someone mind checking my code? Thanks

Answer 1

try to this subtrack process
I added example field, you have this areas change
const asyncSubtrackProcess = async (id, amount) => await User.findOneAndUpdate({
_id: mongoose.Types.ObjectId(id),
userbalance: { $gt: 0 }
},
{
$inc: {
userbalance: - parseInt(amount)
}
});
const result = () => amounts.map(async item => await asyncSubtrackProcess(item.id, item.amount));
result();