使multer upload成为asyc函数

const express = require('express');
const multer = require('multer');

const storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, 'uploads/');
  },
  filename: function (req, file, cb) {
    cb(null, file.originalname);
  }
});

const upload = multer({ storage: storage });

const app = express();

app.post('/upload', upload.single('file'), (req, res) => {
  res.send('File uploaded successfully!');
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});

app.post('/upload', async (req, res) => {
  try {
    await upload.single('file')(req, res);
    res.send('File uploaded successfully!');
  } catch (error) {
    res.status(400).send('An error occurred while uploading the file.');
  }
});