I've got google extension, react frontend app and express server.
I use mediaRecorder to record my screen and insert it into frontend page.There is no problem, video works just fine in frontend

```
const blob = new Blob(chunks, { type: "video/mp4;" });
const savedVideo = document.getElementById("savedVideo");
chunks = [];

const videoURL = window.URL.createObjectURL(blob);
savedVideo.src = videoURL;

var tracks = stream.getTracks();
tracks[0].stop();

let response = await fetch('http://localhost:3001/upload', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/octet-stream',
  },
  body: blob
});

```

The problem starts when i send blob to server.I want to save video(Only on server side)I suppose problem is in handling blob on the server side, maybe I doing smth wrong, here my server code:

```
const express = require("express");
const cors = require('cors');
const fs = require('fs');

const app = express();
const port = 3001;

app.use(cors({
  origin: 'http://localhost:3000'
}));

app.post("/upload", (req, res) => {
  console.log('req.body', req.body)
  req.on('readable', function(){
    const data = req.read();
    if(data) {
      fs.createWriteStream('videeoo.mp4').write(data);
      // also i didnt sure about this method to write file
    }
    console.log('data', data);
  });        
});

app.listen(port, () => {
  console.log(`Server started at http://localhost:${port}`);
});

```

[express logs](https://i.stack.imgur.com/nGOCs.png)

I'am waiting your best practices)Grasias!