My two variables are not equal sometimes but must be - node.js

Question

My two variable "soundTypeFound[0].name" and "req.soundTypes[iteration]" must be the same everytime but once in five times its coming as false.
I think the loop goes more quickly than the function "allSoundTypeQuery.GetSoundTypeByName(item, (soundTypeFound, err) => {}" and the variable "iteration" does not have the time to be incremented as same time as the loop.
Thank you for your help
async function checkSoundTypes (req, res, soundTypesString, error, next) {
let stop = false;
req.soundTypes = soundTypesString.split(',');
let iteration = 0;
for (let item of req.soundTypes) {
await allSoundTypeQuery.GetSoundTypeByName(item, (soundTypeFound, err) => {
if (err) {
return res.status(500).json({"error": "Cannot find the sound type in the DB"});
}
if (soundTypeFound.length <= 0 || soundTypeFound[0].name !== req.soundTypes[iteration]) {
stop = true;
}
iteration++;
if (iteration === req.soundTypes.length) {
if (stop === true) {
error.push("soundTypes");
return res.status(400).json(error);
}else if (err) {
return res.status(400).json(error);
}else {
next();
}
}
});
}
}

Answer 1

Since you were sending a callback function, it will not wait and move forward with the next iteration, so it causing error,now the method will return promise as we are using promisify method of the util module, not it will wait for the promise to resolve and then move to the next line.
const {promisify} = require('util');
async function checkSoundTypes (req, res, soundTypesString, error, next) {
let stop = false;
req.soundTypes = soundTypesString.split(',');
let iteration = 0;
for (let item of req.soundTypes) {
const getSoundTypeByName = promisify(allSoundTypeQuery.GetSoundTypeByName);
const soundTypeFound= await getSoundTypeByName(item);
if (!soundTypeFound) { // this you should check as per your response
return res.status(500).json({"error": "Cannot find the sound type in the DB"});
}
if (soundTypeFound.length <= 0 || soundTypeFound[0].name !== req.soundTypes[iteration]) {
stop = true;
}
iteration++;
if (iteration === req.soundTypes.length) {
if (stop === true) {
error.push("soundTypes");
return res.status(400).json(error);
}else if (err) {
return res.status(400).json(error);
}else {
next();
}
}
}
}