NodeJS - Create a video streaming server

app.js

const express = require('express');
const fs = require('fs');
const app = express();

app.get('/video', function(req, res) {
    const path = '/your/path/to/video-file.mp4';
    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)
    }
});

app.listen(3000, () => console.log('Example app listening on port 3000!'))