如何像netflix一样流式传输视频？

Question

Netflix或Amazon Prime如何快速有效地播放视频？

app.get('/video/:id', function(req, res) {
  var path = req.params.id;
  const stat = fs.statSync(path)
  const fileSize = stat.size
  const range = req.headers.range
  if (range) {
    const parts = range.replace(/bytes=/, "").split("-")
    const start = parseInt(parts[0], 10)
    const end = parts[1] ? parseInt(parts[1], 10) : fileSize - 1
    const chunksize = (end - start) + 1
    const file = fs.createReadStream(path, {
      start,
      end
    })

    const head = {
      'Content-Range': `bytes ${start}-${end}/${fileSize}`,
      'Accept-Ranges': 'bytes'
      'Content-Length': chunksize,
      'Content-Type': 'video/mp4',
    }

    res.writeHead(206, head)
    file.pipe(res)
  } else {
    const head = {
      'Content-Length': fileSize,
      'Content-Type': 'video/mp4',
    }
    res.writeHead(200, head)
    fs.createReadStream(path).pipe(res)
  }
})

我像这种方法一样流视频文件。效果不佳，视频缓冲区过多。帮帮我啦。谢谢