Posted onApr 5, 2024

How to use TURN server with PeerJs

#webdev #javascript #webrtc #tutorial

In this article we are going to learn how we can use the TURN server with the PeerJS

For this, we are going to create a new PeerJs project

This is going to be a simple webrtc application for learning purposes.

The App is going to connect to another peer using PeerJs and send messages, we are going to use TURN server to bypass the NAT in this example.

For a TURN server we are going to use the Metered TURN servers

Here is what we are going to learn in this article

Getting a TURN server solution (Metered TURN servers)
Setting Up a Simple WebRTC Project Using PeerJS
Integrating Metered TURN servers with PeerJs project
Testing the TURN server and the app

In order to integrate TURN server with PeerJs application, you first need a TURN server.

In order to make things easier, we are going to use the Metered TURN service in this example

Getting a TURN server SolutionMetered TURN servers

Step 1: Create a Free account

go to the Metered TURN server website:https://metered.ca/stun-turn

There create a free account. You get unlimited free STUN server usage and 5 gb of free turn server usage when you put in a credit card. That should be enough for our example here

you can also purchase a plan if you like the paid plans are as follows

TURN Growth 150 GB : 99 USD /mo, free 150 GB TURN usage included, 0.40 USD/ GB overage,99.95% Uptime
TURN Business 500 GB: 199 USD /mo, free 500 GB TURN usage included, 0.20 USD/ GB overage,99.99% Uptime
TURN Enterprise 2 TB: 499 USD /mo, free 2 TB TURN usage included, 0.10 USD/ GB overage,99.999% Uptime

Step 2: Creating TURN credentials

When you signup you land up in the dashboard there you can create the TURN credentials

You can manually create credentials and use it in your PeerJS library or
You can use the API to create the credentials as well

While creating the credentials manually is straightforward using the API gives you a lot more features and management control over the TURN server like for example

Add/Remove credentials using the API
Fetch Per-Credential Usage Metrics with API
Enable/Disable teh Credentials with the API
Create auto expiring TURN credentials

You can also select the region, where your TURN server should be located. The recommended is the** Global location**, which automatically routes the traffic to the turn server that is nearest to your users location

apart from this the locations available are

Global
North America Only
E.U Only
Europe Only
Asia Only
Oceana Only
U.S West Only
U.S Central Only
U.S East Only
Canada Central Only
Canada East Only
Europe West Only
Europe Central Only
Asia West Only
Asia East Only
Oceana Only
Canada Only
U.S Only
U.K Only
Seoul Only
Singapore Only
India Only
Australia Only

You can click on the instructions button to know more about the how to use the credential in your app

Setting Up a Simple WebRTC Project Using PeerJS

PeerJS is a wrapper around the web browsers built in webRTC implementation that provides a easy to use peer to peer connection API.

This API is complete, configurable and easy to use API, that handles serialization, peer discovery and connection management

PeerJs is easy to setup for audio/video streaming, file sharing and data channels

Creating a PeerJs Project

In this section we are going to create a new PeerJs project

As stated above, the app is going to be simple webrtc app that is going to connec to another peer and send messages using a TURN server

For a TURN server we are going to use the Metered TURN servers. We have already stated how you can Sign Up for the Metered TURN service above

First, create a nodejs project, create a new directory and name itpeerjs thencd into it

step 1: type the npm init command to initialize a new project. This will create apackage.json file which will look something like this

{"name":"peerjs","version":"1.0.0","description":"","main":"index.js","scripts":{"test":"echo\"Error: no test specified\" && exit 1"},"author":"metered-turn-servers","license":"ISC"}

Creating the UI of the App. (index.html)

In the root folder create a new file and name itindex.html

In the file paste the following code:

<!DOCTYPE html><htmllang="en"><head><metacharset="UTF-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><title>PeerJS Example with TURN Server</title><scriptsrc="https://cdnjs.cloudflare.com/ajax/libs/peerjs/1.3.2/peerjs.min.js"></script><scriptsrc="app.js"defer></script></head><body><h2>PeerJS WebRTC Communication</h2><div><labelfor="peerId">Your Peer ID:</label><inputtype="text"id="peerId"readonly></div><div><labelfor="otherPeerId">Connect to Peer ID:</label><inputtype="text"id="otherPeerId"><buttonid="connectButton">Connect</button></div><div><labelfor="message">Message:</label><inputtype="text"id="message"><buttonid="sendMessageButton">Send Message</button></div><divid="messages"></div></body></html>

What are we doing here:

We are importing the peerjs library through CDN. This enables us to use the library
Then we are linking to the external JavaScript File called theapp.js, this file contains the logic of the PeerJs app that we are creating
Peer ID Display: In the body section we are creating a label and input that shows the user their own PeerJS ID like so

<div><labelfor="peerId">Your Peer ID:</label><inputtype="text"id="peerId"readonly></div>

4Connect to Peer Then in the next section we are allowing the user to connect to another user by putting in the credentials, that is the PeerJs ID of the other user that they want to connect to

<div><labelfor="otherPeerId">Connect to Peer ID:</label><inputtype="text"id="otherPeerId"><buttonid="connectButton">Connect</button></div>

5Send Message: Here we have an input field where the user can write a message that they want to send to another user

<div><labelfor="message">Message:</label><inputtype="text"id="message"><buttonid="sendMessageButton">Send Message</button></div>

6Message Display: It is a<div> with nothing inside adn an id ofmessages. In this div we are going to add the messages that are send and received

<divid="messages"></div>

Creating the APP logic (app.js file)

Next create a file in the root directory and name itapp.js

Paste the following code in theapp.js file

document.addEventListener('DOMContentLoaded',()=>{constpeer=newPeer(undefined,{config:{iceServers:[{urls:"turn:global.relay.metered.ca:80",// Replace with your TURN server URLusername:"370e0c14a753092e97cd645f",// Replace with your TURN usernamecredential:"TJ+gyUoqt2xo3oI2",// Replace with your TURN credential}]}});constpeerIdInput=document.getElementById('peerId');constotherPeerIdInput=document.getElementById('otherPeerId');constconnectButton=document.getElementById('connectButton');constmessageInput=document.getElementById('message');constsendMessageButton=document.getElementById('sendMessageButton');constmessagesDiv=document.getElementById('messages');letdataConnection=null;peer.on('open',id=>{peerIdInput.value=id;});connectButton.addEventListener('click',()=>{constotherPeerId=otherPeerIdInput.value;if(!otherPeerId){alert('Please enter the other peer ID.');return;}dataConnection=peer.connect(otherPeerId);setupDataConnectionEvents();});sendMessageButton.addEventListener('click',()=>{constmessage=messageInput.value;if(!message){alert('Please enter a message to send.');return;}if(dataConnection&&dataConnection.open){dataConnection.send(message);displayMessage(`You:${message}`);messageInput.value='';// Clear the input after sending}else{alert('Data connection is not established. Please connect to a peer first.');}});peer.on('connection',connection=>{dataConnection=connection;setupDataConnectionEvents();});functionsetupDataConnectionEvents(){dataConnection.on('data',message=>{displayMessage(`Peer:${message}`);});dataConnection.on('open',()=>{messagesDiv.innerHTML+='<p>Connection established. You can send messages now.</p>';});dataConnection.on('close',()=>{alert('Data connection has been closed.');});}functiondisplayMessage(message){messagesDiv.innerHTML+=`<p>${message}</p>`;}});

What are we doing here:

(Important) Initializing the code and adding Global variables

let us look at the initializing code and understand what it is doing

document.addEventListener('DOMContentLoaded',()=>{constpeer=newPeer(undefined,{config:{iceServers:[{urls:"turn:global.relay.metered.ca:80",// Use the TURN server URL from Meteredusername:"370e0c14a753092e97cd645f",// TURN server username Obtained from metered.ca/stun-turn websitecredential:"TJ+gyUoqt2xo3oI2",// TURN server credentials Obtained from metered.ca/stun-turn}]}});

We wait for the DON to load then we call a function
this function creates a new PeerJsPeer Object. and we pass theundefined as the first argument here
In the config object we add the Metered TURN credentials that we obtained from the metered turn server website:https://metered.ca/stun-turn

UI Elements and Connection Handling

constpeerIdInput=document.getElementById('peerId');constotherPeerIdInput=document.getElementById('otherPeerId');constconnectButton=document.getElementById('connectButton');constmessageInput=document.getElementById('message');constsendMessageButton=document.getElementById('sendMessageButton');constmessagesDiv=document.getElementById('messages');letdataConnection=null;

You get the elements from the index.html page like peer ID, input messages etc
dataConnection is initialized with null

Displaying the Peer ID

peer.on('open',id=>{peerIdInput.value=id;});

Here the peer js listner waits for theopen event. when the peer ID is ready, the id is displayed in thepeerIdInput field.

Establishing a Connection

connectButton.addEventListener('click',()=>{constotherPeerId=otherPeerIdInput.value;if(!otherPeerId){alert('Please enter the other peer ID.');return;}dataConnection=peer.connect(otherPeerId);setupDataConnectionEvents();});

When the user clicks on theConnect button, the script to establish a connection to the perr whose ID is entered in theotherPeerInput field runs
It calles thepeer.connect and passes the other peer's ID and assigns the returned data connection object todataConnectionsetupDataConnectionEvents is called to initiaze event listners for the new connection

Sending Messages

sendMessageButton.addEventListener('click',()=>{constmessage=messageInput.value;if(!message){alert('Please enter a message to send.');return;}if(dataConnection&&dataConnection.open){dataConnection.send(message);displayMessage(`You:${message}`);messageInput.value='';}else{alert('Data connection is not established. Please connect to a peer first.');}});

Here we are listning on theSend message button. If something is typed in the input field and the connection is established we send the message
The sent messages are also displayed on themessagesDiv after theYou: text and the input is cleared

Receiving Connections and Messages

peer.on('connection',connection=>{dataConnection=connection;setupDataConnectionEvents();});

Nest we are listning for the connections when another peer connects to this peer then we save the connection object in thedataConnection variable and similar to outgoing connections the event listners are setup by the library

Handling connection events

functionsetupDataConnectionEvents(){dataConnection.on('data',message=>{displayMessage(`Peer:${message}`);});dataConnection.on('open',()=>{messagesDiv.innerHTML+='<p>Connection established. You can send messages now.</p>';});dataConnection.on('close',()=>{alert('Data connection has been closed.');});}

Here there are a few things that are hapening

setupDataConnectionEvents function adds listners for the data, open and close events to the current data connection
data event listener displays incoming messages
open event adds a message to themessageDiv, telling us that a connection has been establishedclose event alerts the user that the connection has been closed

Displaying Messages

functiondisplayMessage(message){messagesDiv.innerHTML+=`<p>${message}</p>`;}

this function adds messages to themessagesDiv thus showing messages on the screen

Metered TURN servers

API: TURN server management with powerful API. You can do things like Add/ Remove credentials via the API, Retrieve Per User / Credentials and User metrics via the API, Enable/ Disable credentials via the API, Retrive Usage data by date via the API.
Global Geo-Location targeting: Automatically directs traffic to the nearest servers, for lowest possible latency and highest quality performance. less than 50 ms latency anywhere around the world
Servers in 12 Regions of the world: Toronto, Miami, San Francisco, Amsterdam, London, Frankfurt, Bangalore, Singapore,Sydney, Seoul
Low Latency: less than 50 ms latency, anywhere across the world.
Cost-Effective: pay-as-you-go pricing with bandwidth and volume discounts available.
Easy Administration: Get usage logs, emails when accounts reach threshold limits, billing records and email and phone support.
Standards Compliant: Conforms to RFCs 5389, 5769, 5780, 5766, 6062, 6156, 5245, 5768, 6336, 6544, 5928 over UDP, TCP, TLS, and DTLS.
Multi‑Tenancy: Create multiple credentials and separate the usage by customer, or different apps. Get Usage logs, billing records and threshold alerts.
Enterprise Reliability: 99.999% Uptime with SLA.
Enterprise Scale: With no limit on concurrent traffic or total traffic. Metered TURN Servers provide Enterprise Scalability
5 GB/mo Free: Get 5 GB every month free TURN server usage with the Free Plan
Runs on port 80 and 443
Support TURNS + SSL to allow connections through deep packet inspection firewalls.
Support STUN
Supports both TCP and UDP