How to return file Location after uploading to s3 - express

Question

I am new to Node.js and express.
I use following function to upload image to s3.
function defaultContentType(req, file, cb) {
setImmediate(function () {
var ct = file.contentType || file.mimetype || 'application/octet-stream'
cb(null, ct);
});
}
module.exports = async function (fileName, file) {
aws.config.update({
secretAccessKey: process.env.AWSSecretKey,
accessKeyId: process.env.AWSAccessKeyId,
contentType: defaultContentType,
});
var s3bucket = new aws.S3({
params: {
Bucket: process.env.S3_Bucket_Name,
}
});
var params = {
Key: fileName,
Body: file
};
var fileData = await s3bucket.upload(params, function (err, data) {
if (err) {
throw err;
} else {
return data;
}
});
return fileData;
}
before uploading the image, I resize it using
request(req.file.location, async function (err, response, body) {
var fileInstance = await sharp(body);
var resizeFile = await fileInstance.resize({
height: 150,
fit: 'inside'
});
var data = await s3Upload('mobile_' + req.file.key, resizeFile);
req.mobile = data.Location;
next();
});
The problem I have is;
The image does get resized and saved to s3.
But "s3Upload" function does not return the file location.
Seems like it take some time to complete the operation. Before it get completed, undefined value get return.
Can anyone suggest a way to fix this?
Modified method
module.exports = function (fileName, file, finishCallback) {
// more code
s3bucket.upload(params, function (err, data) {
if (err) {
throw err;
} else {
finishCallback(data);
}
});
}
modified the upload method as
s3Upload('mobile_' + req.file.key, resizeFile, (data) => {
req.mobile = data.Location;
next();
});
This seems to be working as expected.
I am not really sure this is the correct way to do things.
Is there a way to do this correctly?