index.js

import { Router } from 'express'
import fs from 'fs'
import multer, { diskStorage } from 'multer'
import path from 'path'

/**
 * @description
 * Allows to control all malicious content via FormData.
 * @param {{}} file 
 * @param {function} callback 
 */
function sanitizeFile(file, callback) {
  const audioMimeType = 'audio/'
  const imageMimeType = 'image/'
  const isAllowedMimeType =
    file.mimetype.startsWith(imageMimeType) ||
    file.mimetype.startsWith(audioMimeType)
  if (isAllowedMimeType) {
    return callback(null, true)
  }
  callback('Mimetype is not allowed.')
}

const storage = diskStorage({
  destination: function(_req, _file, callback) {
    return callback(null, path.join(__dirname, 'content'))
  },
  filename: function(_req, file, callback) {
    callback(null, `${Date.now()}-${file.originalname}`)
  }
})

const upload = multer({
  storage,
  limits: {
    fileSize: 2000000
  },
  fileFilter: function(_req, file, callback) {
    sanitizeFile(file, callback)
  }
}).single('upload')

const uploadRouter = Router()

uploadRouter.post('/', async (req, res) => {
  upload(req, res, async err => {
    if (err) {
      return res.status(502).json({
        message: err,
        statusCode: 502
      })
    }

    if (!req.file) {
      return res.status(400).json({
        message: 'File not found',
        statusCode: 400
      })
    }

    return res.status(201).json({
      statusCode: 201
    })
  })
})

uploadRouter.get('/', async (req, res) => {
  const { filename } = req.query

  const files = path.join(__dirname, 'content')
  
  fs.readdir(files, (err, files) => {
    if (err) {
      return res.status(502).json({
        message: err,
        statusCode: 502
      })
    }
    
    const fileExist = files.includes(filename)

    if (!fileExist) {
      return res.status(404).json({
        message: `File ${filename} was not found.`,
        statusCode: 404
      })
    }

    const filepath = path.join(__dirname, 'content', files[files.indexOf(filename)])
  
  })
  
})


export default uploadRouter