Node.js: how to use WebRTC

WebRTC (Web Real-Time Communication) is a technology that enables real-time audio, video and data communication between web browsers and other applications. Although it is commonly associated with browsers, WebRTC can also be used server-side using Node.js. In this guide, we'll explore how to use WebRTC in Node.js to build real-time communications applications.

What is WebRTC?

WebRTC is an open source technology supported by Google, Mozilla and other organizations. It provides a set of JavaScript APIs that allow developers to create web applications that support real-time communication, including video calling, audio/video chat, and file sharing.

Using WebRTC in Node.js

To use server-side WebRTC with Node.js, we will need a module called node-webrtc. This module allows us to access WebRTC features directly from Node.js. Here's how to get started:

Step 1: Install node-webrtc

Let's start by creating a new Node.js project and installing the node-webrtc module using npm:

npm install --save node-webrtc

Step 2: Create a WebRTC server

Now that we have node-webrtc installed, we can create a Node.js server that uses this library to handle real-time communication. Here is a code example:

const { RTCPeerConnection, RTCSessionDescription } = require('wrtc');

const configuration = { iceServers: [{ urls: 'stun:stun.l.google.com:19302' }] };
const peerConnection = new RTCPeerConnection(configuration);

peerConnection.onicecandidate = event => {
   if (event.candidate) {
     // Send the ICE candidate to the other peer
   }
};

// Add your handlers for audio/video streams, etc.

// Example of initial offer management
async function handleOffer(offer) {
   await peerConnection.setRemoteDescription(new RTCSessionDescription(offer));
   const answer = await peerConnection.createAnswer();
   await peerConnection.setLocalDescription(answer);

   // Send the answer to the other peer
}

In this example, we are creating a RTCPeerConnection object that will handle the connection with other peers. We also configure the ICE servers that help establish the connection.

Step 3: Communicate with peers

Once the connection is established, you can send and receive streams of data, audio, and video using WebRTC. You can use events like ontrack to manage streams received from peers.

Step 4: Manage ICE applicants

During the connection process, ICE candidates are exchanged between peers to establish the connection. You must properly handle these candidates using onicecandidate events.

Conclusions

In this guide, we explored how to use WebRTC in Node.js to build real-time communication applications. Using the node-webrtc module, you can take advantage of the powerful features of WebRTC directly on the server side. With this basic knowledge, you are ready to start building real-time communication applications with Node.js and WebRTC.