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Receive Message

Receives incoming WhatsApp messages via a webhook server. This node sets up a local HTTP server to listen for incoming messages from Twilio and triggers your automation flow when messages are received.

Common Properties​

  • Name - The custom name of the node.
  • Color - The custom color of the node.
  • Delay Before (sec) - Waits in seconds before executing the node.
  • Delay After (sec) - Waits in seconds after executing node.
  • Continue On Error - Automation will continue regardless of any error. The default value is false.
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If ContinueOnError property is true, no error is caught when the project is executed even if Catch node is used.

Prerequisites​

To receive WhatsApp messages, you need to:

  1. Configure WhatsApp Sandbox or Production WhatsApp Number in Twilio Console
  2. Set up Webhook URL - Configure Twilio to send incoming messages to your webhook endpoint
  3. Expose Local Server - Make your local server accessible to Twilio (using ngrok, tunneling, or public IP)
  4. Configure Firewall - Ensure the webhook port is accessible from external networks
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This node creates a local HTTP server. For production use, ensure your server is properly secured and accessible from Twilio's servers.

Input​

  • Port - The webhook server port for receiving messages. This input exists for compatibility but the actual port is configured via properties. Default: 9001
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The actual port and IP are configured through application properties:

  • robomotion.twilio.receivemessage.port (default: 9001)
  • robomotion.twilio.receivemessage.ip (default: 127.0.0.1)

Output​

The node outputs a message object for each incoming WhatsApp message received:

  • id - Unique identifier for the received message
  • body - Object containing the message details from Twilio:
    • From - Sender's WhatsApp number (format: whatsapp:+14155552671)
    • To - Your WhatsApp number (format: whatsapp:+14155552672)
    • Body - The message text content
    • MessageSid - Twilio's unique message identifier
    • AccountSid - Your Twilio Account SID
    • NumMedia - Number of media attachments
    • MediaUrl0, MediaContentType0 - Media attachment details (if present)
    • Additional Twilio webhook parameters

Options​

  • n/a - This node has no configurable options.

Configuration​

1. Configure Application Properties​

Set the webhook server configuration in your Robomotion properties:

robomotion.twilio.receivemessage.port=9001
robomotion.twilio.receivemessage.ip=127.0.0.1

2. Expose Local Server​

For development/testing, use ngrok to expose your local server:

ngrok http 9001

This provides a public URL like: https://abc123.ngrok.io

3. Configure Twilio Webhook​

In Twilio Console:

  1. Go to your WhatsApp Sender settings
  2. Find "Webhook URL for Incoming Messages"
  3. Set to: https://abc123.ngrok.io/ (or your public URL)
  4. Save configuration

Examples​

Example 1: Auto-Reply System​

Create an auto-reply system for incoming WhatsApp messages:

Flow Structure:

Receive Message
├── Output: message data
└── Send WhatsApp Message
    ├── To Number: {{item.body.From}} (remove "whatsapp:" prefix)
    └── Message: "Thank you for contacting us! We'll respond shortly."

Implementation:

  1. Add Receive Message node (starts the flow)
  2. Extract sender from {{item.body.From}}
  3. Remove whatsapp: prefix: Use string manipulation or JavaScript
  4. Send WhatsApp Message with auto-reply

Example 2: Keyword-Based Responses​

Respond to messages based on keywords:

Flow Structure:

Receive Message
├── Get message body
├── Convert to lowercase
└── Switch (based on keywords)
    ├── Case "hours" → Send business hours
    ├── Case "support" → Create support ticket
    ├── Case "order" → Send order status
    └── Default → Send help menu

Message Processing:

// Extract and clean message
var fromNumber = item.body.From.replace('whatsapp:', '');
var messageText = item.body.Body.toLowerCase();

// Set variables for routing
msg.from = fromNumber;
msg.text = messageText;

Example 3: Customer Support Ticketing​

Create support tickets from WhatsApp messages:

Flow Structure:

Receive Message
├── Parse message details
├── Database - Insert (create ticket)
│   └── ticket_id, customer_phone, message, status: "new"
├── Send WhatsApp Message (confirmation)
│   └── "Ticket #{{ticket_id}} created. Support will contact you soon."
└── Send Email (notify support team)

Example 4: Order Status Inquiry​

Allow customers to check order status via WhatsApp:

Flow Structure:

Receive Message
├── Extract order number from message
│   └── RegEx: #(\d+)
├── Database Query
│   └── SELECT * FROM orders WHERE order_id = {{order_number}}
├── If order found
│   └── Send WhatsApp Message
│       └── "Order #{{order_id}}: {{status}}\nETA: {{delivery_date}}"
└── Else
    └── Send WhatsApp Message
        └── "Order not found. Please check the order number."

Example 5: Multi-Agent Routing​

Route messages to different agents based on content:

Flow Structure:

Receive Message
├── Analyze message content
├── Switch (routing logic)
│   ├── Sales keywords → Notify sales team
│   ├── Support keywords → Create support ticket
│   ├── Billing keywords → Notify billing department
│   └── Default → General inquiry queue
└── Send acknowledgment to customer

Tips​

  • Server Accessibility - For production, host on a server with a public IP or domain, not just localhost.
  • HTTPS Required - Twilio requires HTTPS for webhooks in production. Use a valid SSL certificate.
  • Port Configuration - If port 9001 is in use, change it via application properties.
  • URL Path - The webhook endpoint is always the root path /. Configure Twilio to post to https://yourdomain.com/.
  • Testing with ngrok - ngrok is perfect for development. Remember to update the Twilio webhook URL when ngrok restarts (URL changes).
  • Message Parsing - The body contains URL-encoded form data. The node automatically parses it into an object.
  • Number Format - Incoming numbers include the whatsapp: prefix. Remove it when replying: from.replace('whatsapp:', '').
  • Flow Trigger - This node has 0 inputs (configured in the source code). It acts as a trigger node that starts the flow when messages arrive.
  • Concurrent Messages - The server handles concurrent incoming messages automatically.
  • Error Handling - Wrap subsequent nodes in Try-Catch to handle processing errors gracefully.

Common Errors​

Port Already in Use​

Error: Server fails to start, port 9001 already in use

Solution:

  • Check if another Receive Message flow is already running
  • Change the port via application properties: 
    robomotion.twilio.receivemessage.port=9002
  • Kill the process using the port (check with netstat or lsof)

Webhook Not Receiving Messages​

Error: Messages sent to WhatsApp number but no flow triggers

Solution:

  • Verify ngrok or your tunnel is running and accessible
  • Check Twilio webhook URL is correctly configured
  • Test webhook URL in browser or with curl
  • Ensure firewall allows incoming connections on the webhook port
  • Check Twilio webhook logs in Console for error messages
  • Verify the webhook URL path is / (root)

Invalid URL in Twilio​

Error: "Invalid webhook URL" in Twilio Console

Solution:

  • Ensure URL uses HTTPS (required for production)
  • Verify URL is publicly accessible
  • Check URL format: https://yourdomain.com/ (must end with /)
  • Test URL accessibility from external network
  • For development, use ngrok HTTPS URL

Messages Not Parsing Correctly​

Error: Message body is empty or malformed

Solution:

  • Check Twilio is sending POST requests with form data
  • Verify the node is receiving the webhook properly
  • Log the raw item.body object to inspect contents
  • Ensure no middleware is interfering with request body

Server Stops Responding​

Error: Webhook stops receiving messages after running for a while

Solution:

  • Check application logs for errors
  • Ensure no memory leaks in message processing logic
  • Restart the flow
  • Monitor server resources (CPU, memory)
  • Implement proper error handling in downstream nodes

HTTPS Certificate Errors​

Error: Twilio rejects webhook due to SSL certificate issues

Solution:

  • Use a valid SSL certificate (not self-signed)
  • Ensure certificate is not expired
  • Verify certificate matches your domain
  • For development, ngrok provides valid HTTPS automatically
  • Consider using Let's Encrypt for free SSL certificates

Configuration Examples​

Development Setup (ngrok)​

  1. Start ngrok:
ngrok http 9001

  1. Copy the HTTPS URL (e.g., https://abc123.ngrok.io)

  2. Configure Twilio webhook:

    • URL: https://abc123.ngrok.io/
    • Method: POST

  3. Run your flow with Receive Message node

Production Setup​

  1. Configure application properties:
robomotion.twilio.receivemessage.port=443
robomotion.twilio.receivemessage.ip=0.0.0.0
  1. Set up reverse proxy (nginx) with SSL:
server {
    listen 443 ssl;
    server_name yourdomain.com;

    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;

    location / {
        proxy_pass http://127.0.0.1:9001/;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}
  1. Configure Twilio webhook:
    • URL: https://yourdomain.com/
    • Method: POST