Multer Upload Not Working?

What is wrong here. I tried uploading to multer but it does not work.

var multer = require('multer');

var storage = multer.diskStorage({
  destination: (req, file, cb) => {
    cb(null, `${process.cwd()}/uploads/`)
  },
  filename: (req, file, cb) => {
    cb(null, file.originalname)
  }
});
var upload = multer({
  storage: storage
});
// Export routes
router.post('/upload', upload.single('csv'), (req, res, next) => {
  res.status(200).json({
    message: `File uploaded successfully on '${process.cwd()}/uploads/${req.file.filename}`
  });
});

What is wrong here