gistfile1.js

const http = require('http')
const fsp = require('fs').promises
const stream = require('stream')
const pipeline = util.promisify(stream.pipeline)

module.exports = async function downloadFile(url, opts = {}) {
  const res = await new Promise((resolve, reject) => http
    .get(url)
    .on('response', resolve)
    .on('error', reject)
  )

  let size = parseInt(res.headers['content-length'])
  let pos = 0

  const dst = fs.createWriteStream(filePath)
  try {
    await pipeline(
      res,
      new stream.Transform({
        transform(chunk, encoding, callback) {
          pos += chunk.length
          if (size) {
            console.log(`Progress: ${pos/size}`)
          }
          callback()
        }
      }),
      dst
    )
  } catch (err) {
    await fsp.unlink(filePath)
    throw err
  }
}