WhatsApp Sender

Overview

This node enables sending WhatsApp messages through a WhatsApp API service. It supports sending plain text messages, files with an optional message, and pre-approved message templates with variable substitution. This node is useful for automating communication workflows such as customer support notifications, marketing campaigns, or transactional alerts via WhatsApp.

For the Send File with Message operation specifically, the node sends a file (from a URL) along with a custom text message to a specified WhatsApp number. This is beneficial when you want to share documents, images, or other supported file types alongside contextual information.

Practical Example

• Sending a PDF invoice to a customer with a personalized message.
• Sharing product images with descriptions during a sales conversation.
• Delivering reports or spreadsheets directly to team members on WhatsApp.

Properties

Output

The node outputs a JSON object for each input item processed. The output includes:

• success: Boolean indicating if the message was sent successfully.
• operation: The operation performed (sendFile in this case).
• to: The recipient's WhatsApp number.
• Additional data returned from the WhatsApp API under the data field, which may include message IDs or status details.

If the message fails to send, the output contains:

• success: false
• error: Error message describing the failure.
• operation and to fields for context.

The node does not output binary data.

Dependencies

• Requires an API key credential for authenticating with the WhatsApp API service.
• The node makes HTTP POST requests to https://wsp.multist.net/api/create-message.
• Proper configuration of the API credentials within n8n is necessary.

Troubleshooting

• Invalid phone number format error: Ensure the WhatsApp number includes the country code and matches the pattern +1234567890.
• Message length exceeds limit: Messages longer than 1000 words will be rejected; shorten your message accordingly.
• Unsupported file type error: Only files with extensions jpg, jpeg, png, webp, pdf, docx, xlsx, csv, and txt are accepted. Verify the file URL points to a supported format.
• API request failures: Check that the API credentials are valid and have sufficient permissions. Network issues or incorrect endpoint URLs can also cause failures.
• If "continue on fail" is enabled, errors will be reported per item without stopping the workflow.

Links and References

• WhatsApp Business API Documentation
• n8n HTTP Request Node Documentation
• File Format Support Reference