JavaScript Room Monitor

Twilio’s JavaScript Room Monitor is a browser-based tool that displays real-time information and metrics about a Twilio Video Room. It gathers and processes information from the Room object, including information about Participants’ bandwidth, jitter, and packet loss, and displays the information in a modal window in the video application.

Below is as an example of interacting with the Video Room Monitor in a running application:

The JavaScript Room Monitor can be added to any Twilio Video JavaScript application to help during all stages of development and for debugging in-progress calls. The Video Room Monitor is an open-source project, so you may also fork and customize the application to fit your specific use case.

Browser support

Add the Room Monitor to your application

NPM

You can install the Video Room Monitor directly from npm.

npm install @twilio/video-room-monitor --save

After installing, you can import @twilio/video-room-monitor and open the Monitor like so:

import Video from 'twilio-video';
import { VideoRoomMonitor } from '@twilio/video-room-monitor';

Video.connect('token').then((room) => {
  VideoRoomMonitor.registerVideoRoom(room);
  VideoRoomMonitor.openMonitor();
});

Script tag

You can also copy twilio-video-room-monitor.min.js from the dist/browser folder after npm installing it and include it directly in your web app using a <script> tag.

<script src="https://my-server-path/twilio-video-room-monitor.min.js"></script>

Using this method, you can register a room and open the Monitor like so:

window.Twilio.VideoRoomMonitor.registerVideoRoom(room);
window.Twilio.VideoRoomMonitor.openMonitor();

Console script quickstart (not for production use)

To quickly use the Video Room Monitor in any Twilio Video JavaScript application, you can run the following snippet in the browser console to load and open the Monitor. Note that the Room object must be exposed as a global variable (the sample below assumes the global variable is called twilioRoom) so that it can be registered with the Monitor.

(() => {
  const script = document.createElement('script');
  script.src = 'https://cdn.jsdelivr.net/npm/@twilio/video-room-monitor/dist/browser/twilio-video-room-monitor.min.js';
  script.onload = () => {
    // Register your Twilio Video Room here
    window.Twilio.VideoRoomMonitor.registerVideoRoom(twilioRoom);
    window.Twilio.VideoRoomMonitor.openMonitor();
  };
  document.body.appendChild(script);
})();

The script above opens the Monitor. You can then interact with the Monitor in your browser's console like so:

VideoRoomMonitor.toggleMonitor(); // toggle the monitor open or closed

We do not recommend this method for production use, because we do not control the availability of the jsDelivr CDN.

Use the Room Monitor

Below are the methods that are available on the Video Room Monitor. You can use these in your application's code, or call them in the browser's console to interact with the Monitor while your application is running.

Register the Video Room with the Monitor

This is a required step to be able to use the Video Room Monitor. This registers a Twilio Video Room with the Monitor.

To register a Room, you can run the following line of code, passing in the Room object that's returned when you connect to a Video Room with the Twilio Video JavaScript SDK.

VideoRoomMonitor.registerVideoRoom(newRoom);

Open the Monitor

To open the Room Monitor after you have registered it, you can use the openMonitor method.

VideoRoomMonitor.openMonitor();

Opening the Video Room Monitor emits an opened event. You can listen for this opened event with the following code:

VideoRoomMonitor.on('opened', () => console.log('the monitor has been opened'));

Close the Monitor

You can close the Monitor with the closeMonitor method:

VideoRoomMonitor.closeMonitor();

Closing the Monitor emits a closed event. You can listen for the closed event with the following code:

VideoRoomMonitor.on('closed', () => console.log('the monitor has been closed'));

Toggle the Monitor open or closed

You can use the toggleMonitor method to toggle the Monitor open or closed. If the Monitor is closed when you call this method, the Monitor will open and emit the opened event. If the Monitor is open when you call toggleMonitor, it will close the Monitor and emit the closed event.

VideoRoomMonitor.toggleMonitor();

Check if the Monitor is open

The Monitor has an isOpen property, which is a Boolean indicating whether or not the Monitor is open.

VideoRoomMonitor.isOpen;

Available metrics and information

The Room Monitor has two tabs: Info and Stats. Under the Info tab, you will find information about the Room and all of its Participants and their tracks. The Stats tab contains graphs of the bitrate sent and received over the course of the video call for the local Participant.

Info

In the Info tab, you will find metrics for both the local and remote Participants. For each Participant and each track, you can view properties and metrics that are helpful for making optimizations or assessing media quality, such as packet loss percentage and jitter. The Info tab also includes relevant metadata about the Room and its Participants, such as the media region selected or the ConnectOptions of the local Participant.

Room

Displays information about the Room object.

The Room information will also display the Room's ConnectOptions that were configured when connecting to the Room.

Participants

Displays information about remote and local Participants, as well as the Participants' tracks.

Data Tracks

Displays information about a Participant's published data tracks.

Audio Tracks

Displays information about a Participant's published audio tracks.

Video Tracks

Displays information about a Participant's published video tracks.

Media Stream Tracks

Displays information about the Media Stream Tracks attached to either a video or audio track.

Stats

The Stats tab displays a graph of the sent and received bitrate summed across all tracks (audio, video, and data) during the video chat, reported in kbps. The x-axis displays the local time.