DEV Community

Cover image for building Node.js video streaming in 5 minutes
alguerocode
alguerocode

Posted on

building Node.js video streaming in 5 minutes

hi folks, in this blog we will build a Node.js video streaming application in like 10 minutes.

Image description

prerequisite

  • install Node.js in your computer

what is streaming

Streams are collections of data — just like arrays or strings. The difference is that streams might not be available all at once, and they don’t have to fit in memory. This makes streams really powerful when working with large amounts of data, or data that’s coming from an external source one chunk at a time.

setup [ 1 ] - Geting started

1 - create folder and name it vido-streaming
2 - initialize npm in your project npm init -y
3 - install this packages

dependencies.

#### npm install express
Enter fullscreen mode Exit fullscreen mode

development dependencies.

npm install -D nodemon
Enter fullscreen mode Exit fullscreen mode

add this script to your package.json file.

"start": "nodemon index.js"
Enter fullscreen mode Exit fullscreen mode

setup [2] - setup Node.js server

1 - create index.js file in your project root.
2 - add this code below

const express = require("express");

const app = express(); // setup express application
const PORT = process.env.PORT || 3000;

app.listen(PORT, () => {
  console.log("SERVER STARTED AT PORT: " + PORT);
});
Enter fullscreen mode Exit fullscreen mode

this code starting web server using express framework and listening to port: 3000.

setup [3] - serving html page

now we want to serve an html page with video element to the Frontend.

1 - create public folder in your project root.
2 - create index.html file in created folder (public) and add this html code.


<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Home | Video Streaming</title>
  </head>
  <body>
    <video 
    controls 
    src="/video" 
    id="video-stream" 
    poster="/poster.jpeg" 
    width="700"
    >
    </video>
  </body>
</html>
Enter fullscreen mode Exit fullscreen mode
  • controls : Specifies that video controls should be displayed (such as a play/pause button etc).

  • src : Specifies the URL of the video file.

  • poster: Specifies an image to be shown while the video is downloading, or until the user hits the play button.

serving html file

we need to send the html page to the users. add this code below in index.js file.

app.get("/", (req, res) => {
try {
    res.sendFile(__dirname + "/public/index.html");
} catch (err) {
    res.status(500).send("internal server error occurred")
}
});
Enter fullscreen mode Exit fullscreen mode

what that code does, is listening to get request in base URL of the application, when it get the response will be send file by using sendFile and first parameter is html file path.

note: __dirname is the root path of the current directory.

Serving Poster Image - setup [4]

poster is image will be shown until the video is downloading or user click the video.
note : you need to any image you want in public directory that you make.
see the code below

app.get("/:file_name", (req, res) => {
    try {
        res.sendFile(__dirname + req.params.file_name);
    } catch (err) {
        res.status(500).send("internal server error occurred");
    }
});
Enter fullscreen mode Exit fullscreen mode

Streaming video - setup[5] and Final

import required node.js modules

when streaming the video we need to import two Node.js build-in library in the top of file.

const  fs = require("fs");
const  path = require("path");
Enter fullscreen mode Exit fullscreen mode

fs : file system module allows you to work with the file system on your computer. To include the File System module.

path: allows you to interact with file paths easily. The path module has many useful properties and methods to access and manipulate paths in the file system.

setup video API function

add this code before Serving Poster Image function, because nodejs will go throw the express middlewares and if the requested url is /video it will be match the Serving Poster Image middlewaree not the video middleware.
note : you need to add random video in public file.

app.get("/video", (req, res) => {
// indicates the part of a document that the server should return
// on this measure in bytes for example: range = 0-6 bytes.
const  range = req.headers.range;
if (!range) res.status(400).send("Range must be provided");

const  videoPath = path.join(__dirname, "public", "video.mp4");
// extract video size by using statSyn()
const  videoSize = fs.statSync(videoPath).size;
// 10 powered by 6 equal 1000000bytes = 1mb
const  chunkSize = 10 ** 6; 

// calculating video where to start and where to end.
const  start = Number(range.replace(/\D/g, ""));
const  end = Math.min(start + chunkSize, videoSize - 1);
const  contentLength = end - start + 1;

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

res.writeHead(206, headers);
// creating readStream (stdin).
const  videoStream = fs.createReadStream(videoPath, { start, end });

// create live stream pipe line
videoStream.pipe(res);
});
Enter fullscreen mode Exit fullscreen mode

and then run npm run start. to see your work.

what is pipe() in streaming

Streams make for quite a handy abstraction, and there's a lot you can do with them - as an example, stream.pipe(), the method used to take a readable stream and connect it to a writeable stream. the writable stream is user we request him the data buffers.

project source code: https://github.com/alguerocode/video-streaming
follow me in github: alguerocode

thank you for reading.

Top comments (1)

Collapse
 
alguercode profile image
alguerocode

I hope you to like it