How to upload compressed image to mongodb using sharp & nodeJS - node.js

Question

I want to upload compressed image to database. I'm using sharp ( npm package) for that purpose & using nodeJS as backend stack. I'm using multer to upload image.
My Code :
const express = require('express')
const mongoose = require('mongoose')
const path = require('path')
const cors = require('cors')
const sharp = require('sharp')
const bodyParser = require('body-parser')
const fs = require('fs')
const multer = require('multer')
const app = express()
const { HelpModel, VolunteerModel } = require('./models/model')
require('dotenv').config()
app.use(cors())
app.use(express.static('./build'))
app.use(bodyParser.urlencoded({ extended: true }));
const storage = multer.diskStorage({
destination: (req, file, cb) => {
cb(null, 'upload-data')
},
filename: (req, file, cb) => {
cb(null, Date.now() + '-' + file.originalname);
}
})
const fileFilter = (req, file, cb) => {
if (file.mimetype.startsWith('image')) cb(null, true)
else cb('Invalid File', false)
}
const Upload = multer({ storage, fileFilter })
const dataBase = "mongodb url"
mongoose.connect(dataBase,
{ useNewUrlParser: true, useUnifiedTopology: true })
.then(() => console.log("Mongoose is connected"))
.catch(e => console.log("could not connect"))
app.post('/help', Upload.single('image'), async (req, res) => {
const unique = Date.now() + '-' + '.jpeg'
const imgPath = path.resolve(__dirname + '/upload-data/' + unique);
const resize = async () => {
await sharp(req.file.path).resize(188, 280).jpeg({
quality: 100,
chromaSubsampling: ('4:4:4')
}).toFile(imgPath, (err, info) => {
if (err) console.log(err)
else console.log(info)
})
}
resize()
const newData = new HelpModel({
location: req.body.location,
contact: req.body.contact,
about: req.body.about,
img: {
data: fs.readFileSync('upload-data/' + unique),
contentType: 'image/png'
}
})
newData.save().then( () =>console.log('UPLOADED')).catch(err=>console.log(err,'ERROR OCCURED'))
const rec = await HelpModel.find({})
// res.json(rec)
res.redirect('/help')
})
const port = process.env.PORT || 8000
app.listen(port, () => console.log(`SERVER RUNNING AT PORT ${port}`))
Code is almost working as I desire, it resizes & compress the image uploaded by user and saves it in required destination in local storage.
But while uploading file to database, it is unable to access the file from local storage.
And when I'm hardcoding the file it is able to upload to database.
I'm not able to figure out why it is happening. My guess is the code might be asyncronous & data: fs.readFileSync('upload-data/' + unique) is trying to access file before it is actually upoaded & stored to local storage. After making it syncronous it is still performing in same way.