DEV Community

Cover image for How to Code a Video Streaming Server using NodeJS
Abdisalan
Abdisalan

Posted on • Updated on

How to Code a Video Streaming Server using NodeJS

Do you want to stream video in your app without needing users to download the entire video? Here's how to do exactly that using NodeJS.

Final Result

Here's the end result of what we're gonna make.
Video player with buffering timeline

Notice that light grey bar on the video timeline? That's the HTML5 Video Element buffering the video from our NodeJS server!

If you want to git clone the code and play with it yourself, here's the link to my GitHub Repo! https://github.com/Abdisalan/blog-code-examples/tree/master/http-video-stream

Part 1: Setup npm project

You'll need to install NodeJS and run:

mkdir http-video-stream
cd http-video-stream
npm init
npm install --save express nodemon
Enter fullscreen mode Exit fullscreen mode

Part 2: index.html

We need to create a HTML5 Video element, and set the source as "/video", which is where server's endpoint is.

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>HTTP Video Stream</title>
  </head>
  <body>
    <video id="videoPlayer" width="650" controls muted="muted" autoplay>
      <source src="/video" type="video/mp4" />
    </video>
  </body>
</html>

Enter fullscreen mode Exit fullscreen mode

Part 3: index.js

Now lets setup our node server so that on "/" endpoint it serves our index.html page.

const express = require("express");
const app = express();

app.get("/", function (req, res) {
  res.sendFile(__dirname + "/index.html");
});

app.listen(8000, function () {
  console.log("Listening on port 8000!");
});

Enter fullscreen mode Exit fullscreen mode

Part 4: package.json -- Run our server

Add a start script to your package.json so that we can run our server using npm start command.
There's more in your package.json file but I just want you to copy this start script. It uses nodemon to run index.js and restarts the server every time you save the index.js file so you don't need to restart the server yourself!

{
  "scripts": {
    "start": "nodemon index.js"
  }
}
Enter fullscreen mode Exit fullscreen mode

Now you should be able to run

npm start
Enter fullscreen mode Exit fullscreen mode

and see our app running on port 8000. Open your browser and go to http://localhost:8000 to see if it worked.

Part 5: index.js (Again)

We're almost there!
For this final stage, you'll need to either find an mp4 video file, or download the one I've provided in my GitHub project link.
https://github.com/Abdisalan/blog-code-examples/tree/master/http-video-stream
Here's the "/video" endpoint for our server.

// in the imports above
const fs = require("fs");

app.get("/video", function (req, res) {
  // Ensure there is a range given for the video
  const range = req.headers.range;
  if (!range) {
    res.status(400).send("Requires Range header");
  }

  // get video stats (about 61MB)
  const videoPath = "bigbuck.mp4";
  const videoSize = fs.statSync("bigbuck.mp4").size;

  // Parse Range
  // Example: "bytes=32324-"
  const CHUNK_SIZE = 10 ** 6; // 1MB
  const start = Number(range.replace(/\D/g, ""));
  const end = Math.min(start + CHUNK_SIZE, videoSize - 1);

  // Create headers
  const contentLength = end - start + 1;
  const headers = {
    "Content-Range": `bytes ${start}-${end}/${videoSize}`,
    "Accept-Ranges": "bytes",
    "Content-Length": contentLength,
    "Content-Type": "video/mp4",
  };

  // HTTP Status 206 for Partial Content
  res.writeHead(206, headers);

  // create video read stream for this particular chunk
  const videoStream = fs.createReadStream(videoPath, { start, end });

  // Stream the video chunk to the client
  videoStream.pipe(res);
});
Enter fullscreen mode Exit fullscreen mode

The HTML5 video element makes a request to the /video endpoint, and the server returns a file stream of the video, along with headers to tell which part of the video we're sending over.

For a chunk size, I've decided 1MB but you could change that to whatever you like! Another great benefit of this is that we don't need to code the stream to continuously deliver the video data, the browser handles that gracefully for us.

For an in-depth line by line playback on how this works, consider watching my YouTube video on this topic.

Now, you've got a working video streaming server using NodeJS!

Happy Streaming! ✌

Latest comments (29)

Collapse
 
nimaessi profile image
nima essi

error net::ERR_FILE_NOT_FOUND

Collapse
 
csandman profile image
Christopher Sandvik

"For a chunk size, I've decided 1MB but you could change that to whatever you like!"

Is there any info on how to decide a chunk size? I've seen 1MB in a few articles but I haven't seen any reasons for it.

Collapse
 
vrobbi profile image
vrobbi

Works perfectly with my own .mp4 files, thank you

Collapse
 
elliot__c8f94cdeeaa8d318b profile image
Elliot • Edited

Thanks for this. The way it's written works in Chrome but not Safari. To make it work in Safari I had to modify the code from this:

  const CHUNK_SIZE = 10 ** 6; // 1MB
  const start = Number(range.replace(/\D/g, ""));
  const end = Math.min(start + CHUNK_SIZE, videoSize - 1); 
Enter fullscreen mode Exit fullscreen mode

To this:

   //Safari range header has start and end, vs. Chrome has just start
   let parts = range.split('=')[1]
   let start = Number(parts.split('-')[0])
   let end = Number(parts.split('-')[1])

   //For Chrome
   if (!end) {
       const CHUNK_SIZE = 10 ** 6
       end = Math.min(start + CHUNK_SIZE, videoSize - 1)
   } 
Enter fullscreen mode Exit fullscreen mode
Collapse
 
cybergen49 profile image
Cyber

Just came across this post while searching for exactly this, and I'm happy to report that all has gone smoothly! I refactored the code a bit to work with Node's built-in http module, since that's what the rest of my project is using, and made a couple changes to ensure downloading (via the default video player's Download option) works correctly.

Collapse
 
yas1n67 profile image
yas1n67

How can I stream two different videos?

Collapse
 
yas1n67 profile image
yas1n67

How can play more than one video?

Collapse
 
shahinghasemi profile image
shahinghasemi

does fs.createReadStream uses sockets under the hood?

Collapse
 
rizadwiandhika profile image
Riza Dwi

Great articles! Really insightful to me since i'm starting curious in streaming

I wonder that if this stream way uses http protocol, does this mean we use tcp protocol ?

I just recently learned about tcp & udp protocols
where one of the usecases of udp is to serve connectionless data transfer (which is perfect in this video streaming case)

Collapse
 
anandbej profile image
anandkumar

I'm not able to stream the video. I'm getting the "Requires Range header" response.
I tried doing const range = "bytes=0-1023"; but that didnt work too. The player just appears and doesnt play the video

Collapse
 
gazee profile image
gazee

i also got same erroot

how it is solve .did u got it?

Collapse
 
cybergen49 profile image
Cyber

I ran into the same error. The fix seems to be to set your Content-Type header before checking for Range.

Collapse
 
lokuedo5000 profile image
Brayan

Hi, I want to do that, but with webtorrent, how do I do that?

Collapse
 
anztrax profile image
andrew ananta

wow. this is awesome... thanks for sharing bro

Collapse
 
bharathvajganesan profile image
Bharathvaj

Modern browser like Chrome does this video streaming by default. 🤔

Collapse
 
elbigans04 profile image
rhafael bijaksana

thank man. this is very helpful

Collapse
 
son0nline profile image
Son0nline

Pls help, I'm tried with 600MB video
It ok in localhost but failed in LAN

Collapse
 
acagastya profile image
Agastya

Were you trying it on iOS/Safari by any chance? I faced the problem when trying to make it work on iOS, so I followed this blog.logrocket.com/streaming-video.... Safari-based browsers need a different way of handling things.