join-session

name	join-session
description	Join a CometChat call session using CometChatCalls.joinSession with SessionSettings and an HTMLElement container. Use when joining calls, configuring session settings, voice vs video calls, or generating tokens. Triggers on "join session", "join call", "start call", "SessionSettings", "joinSession".
inclusion	manual

CometChat Calls SDK v5 — Join Session

Overview

Join a call session using CometChatCalls.joinSession(). Requires a call token (generated from a session ID), a SessionSettings object, and an HTML container element to render the call UI.

Key Imports

import { CometChatCalls, type SessionSettings } from '@cometchat/calls-sdk-javascript';

Implementation

HTML Container

<div id="call-container" style="width: 100%; height: 100vh;"></div>

Generate Token + Join (Recommended)

const container = document.getElementById('call-container') as HTMLElement;

// Step 1: Generate a call token from session ID
const { token } = await CometChatCalls.generateToken(sessionId);

// Step 2: Configure session settings
const sessionSettings: SessionSettings = {
  sessionType: 'VIDEO',
  layout: 'TILE',
  startAudioMuted: false,
  startVideoPaused: false,
};

// Step 3: Join the session
const result = await CometChatCalls.joinSession(token, sessionSettings, container);
if (result.error) {
  console.error('Failed to join:', result.error);
}

Voice Call vs Video Call

// Video call
const videoSettings: SessionSettings = {
  sessionType: 'VIDEO',
  layout: 'TILE',
  startVideoPaused: false,
};

// Voice call
const voiceSettings: SessionSettings = {
  sessionType: 'VOICE',
  layout: 'SPOTLIGHT',
  startVideoPaused: true,
};

Join with Pre-generated Token

If your backend generates the token:

const result = await CometChatCalls.joinSession(backendToken, sessionSettings, container);

Leave Session

CometChatCalls.leaveSession();

End Session for All

CometChatCalls.endSessionForAll();

Gotchas

• The container must be a visible DOM element with explicit dimensions (width/height)
• All participants must use the same session ID to join the same call
• sessionType values are 'VIDEO' and 'VOICE' (not "AUDIO")
• joinSession() returns { data, error } — check error for failures
• generateToken() requires the user to be logged in — it uses the cached auth token
• Call joinSession only after SDK is initialized and user is logged in
• The call UI renders inside the container — the SDK manages the DOM within it