manual_start_stop_using_js

Zoom RTMS Realtime Media Streaming Service

This Node.js application demonstrates how to manually start and stop Zoom's Realtime Media Streaming (RTMS).

Project Overview

• Listens for Zoom webhook events related to RTMS.
• Connects to signaling and media WebSocket servers.
• Captures and processes realtime transcript data.
• Supports multiple media types: audio, video, transcript, and chat.
• Includes automatic RTMS stop functionality after a configurable duration.

Environment Variables

Create a .env file with the following keys:

ZOOM_CLIENT_ID=your_zoom_client_id
ZOOM_CLIENT_SECRET=your_zoom_client_secret
WEBHOOK_PATH=/webhook
access_token=your_zoom_access_token
PORT=3000
# Optional: start/stop RTMS for a specific invitee already in the meeting.
# Omit to use the user represented by access_token.
RTMS_PARTICIPANT_USER_ID=zoom_user_id

Features

• Validates Zoom webhook events for meeting lifecycle.
• WebSocket handshakes secured with HMAC SHA256 signatures.
• Realtime transcript stream capture from Zoom meetings.
• Automatic RTMS stop scheduling after 10 seconds (configurable).
• Handles keep-alive requests and maintains connection health.
• Automatically cleans up connections when meetings end.
• Optionally targets a specific joined invitee with RTMS_PARTICIPANT_USER_ID.

Endpoints

• POST /webhook – Handles Zoom RTMS webhook events.

Webhook Events Handled

• meeting.started – Initiates RTMS start and schedules automatic stop
• meeting.rtms_started – Connects to signaling WebSocket
• meeting.rtms_stopped – Logs meeting stop event

How It Works

Step 1: Webhook Receiver

The application listens for Zoom webhook events on /webhook endpoint.

Step 2: Meeting Started Event

When meeting.started is received:

• Step 2a: Listen to meeting started event
• Step 2b: Get access token from environment. To implement complete logicfor authorization, please visit here
• Step 2c: Make API call to start RTMS using the meeting ID from the webhook.

If RTMS_PARTICIPANT_USER_ID is set, the request includes settings.participant_user_id. The participant must be an invitee who has already joined the meeting. Without it, Zoom uses the user represented by the access token.

Step 3: RTMS Started Event

When meeting.rtms_started is received, the application connects to Zoom's signaling WebSocket.

Step 4: Generate Signature

Creates HMAC SHA256 signature for authentication handshake using client ID, meeting UUID, and stream ID.

Step 5: WebSocket 1 - Signaling Connection

• Connects to Zoom's signaling WebSocket server
• Sends handshake request with meeting details and signature
• Receives media server URL upon successful handshake

Step 6: WebSocket 2 - Media Connection

• Connects to media WebSocket server
• Sends media handshake requesting transcript stream
• Receives and processes real-time transcript data

Step 7: Stop RTMS

Automatically stops RTMS after 10 seconds using Zoom API.

Message Types Handled

• msg_type: 1 – HANDSHAKE_REQUEST
• msg_type: 2 – HANDSHAKE_RESPONSE
• msg_type: 3 – MEDIA_HANDSHAKE_REQUEST
• msg_type: 4 – MEDIA_HANDSHAKE_RESPONSE
• msg_type: 5 – TRANSCRIPT_DATA
• msg_type: 7 – CLIENT_READY_ACK
• msg_type: 12 – KEEP_ALIVE_REQUEST
• msg_type: 13 – KEEP_ALIVE_RESPONSE

The REST start/stop request uses PATCH /live_meetings/{meetingId}/rtms_app/status. The access token needs the appropriate RTMS status scope, such as meeting:write or the corresponding admin/participant granular scope.

Prerequisites

• Node.js v14 or higher
• A valid Zoom App with webhook events and meeting and RTMS scopes.
• Ngrok or another tunneling service for public webhook exposure

Installation

npm install

Running the Server

node rtms.js

The server will start on port 3000 and listen for webhook events.

Notes

• RTMS is automatically stopped after 10 seconds to demo the stop action of the API
• All WebSocket connections are properly closed when meetings end
• Transcript data is logged to console for debugging

Webhook Delivery Authentication

Normal Zoom webhook deliveries are verified against the exact raw request body using x-zm-signature and x-zm-request-timestamp. Configure ZOOM_SECRET_TOKEN with the Marketplace app's webhook Secret Token. Requests with missing, invalid, or stale signatures are rejected; the default replay window is 300 seconds and can be changed with WEBHOOK_TIMESTAMP_TOLERANCE_SECONDS.