Send Bulk WhatsApp Messages from Google Sheets (using WaSenderAPI)

This n8n workflow automates the process of sending bulk WhatsApp messages to a list of contacts stored in a Google Sheet, leveraging the WaSenderAPI. It's designed to run on a schedule, fetch new contacts, and send personalized messages with a built-in delay to prevent API rate limiting.

What it does

1. Triggers on a schedule: The workflow starts automatically at predefined intervals (e.g., daily, hourly).
2. Reads Google Sheet: It connects to a specified Google Sheet and retrieves all rows, treating each row as a contact with message details.
3. Limits Items (Optional): A Limit node is included, which can be configured to process only a certain number of items from the Google Sheet per execution. This is useful for testing or managing message volume.
4. Loops Through Contacts: For each contact (row) from the Google Sheet, the workflow performs the following steps:
   • Sends WhatsApp Message: It makes an HTTP POST request to the WaSenderAPI to send a WhatsApp message using the contact's phone number and a predefined message template.
   • Waits: After sending each message, it introduces a delay (e.g., 5 seconds) to avoid hitting API rate limits and ensure reliable message delivery.

Prerequisites/Requirements

• n8n Instance: A running n8n instance (cloud or self-hosted).
• Google Sheets Account: A Google account with access to the spreadsheet containing your contact list.
  • Google Sheets Credential: You'll need to set up a Google Sheets OAuth2 credential in n8n.
• WaSenderAPI Account: An active account with WaSenderAPI or a similar WhatsApp API service.
  • WaSenderAPI Endpoint & API Key: You'll need your WaSenderAPI endpoint URL and API key to configure the HTTP Request node.

Setup/Usage

1. Import the Workflow:
   • Copy the provided JSON workflow definition.
   • In your n8n instance, go to "Workflows" and click "New".
   • Click the "Import from JSON" button and paste the workflow JSON.
2. Configure Google Sheets Node (Node ID: 18):
   • Click on the "Google Sheets" node.
   • Select or create a new Google Sheets OAuth2 credential.
   • Specify the Spreadsheet ID and Sheet Name where your contact data is located.
   • Ensure the sheet has columns for phone numbers and any other data you want to use in your message.
3. Configure HTTP Request Node (Node ID: 19):
   • Click on the "HTTP Request" node.
   • Set the Method to POST.
   • Enter your WaSenderAPI Endpoint URL. This will typically look something like https://api.wasender.com/send.
   • In the Headers section, add your API key (e.g., Authorization: Bearer YOUR_WASENDER_API_KEY).
   • In the Body section, configure the JSON payload to send the message. This will likely include:
     • phone: Reference the phone number from the Google Sheet (e.g., {{ $json.phone_number_column_name }}).
     • message: Construct your message, potentially using data from the Google Sheet (e.g., Hello {{ $json.name_column_name }}, your appointment is tomorrow.).
4. Configure Schedule Trigger Node (Node ID: 839):
   • Click on the "Schedule Trigger" node.
   • Define how often you want the workflow to run (e.g., every day at 9 AM, every hour).
5. Configure Wait Node (Node ID: 514):
   • Click on the "Wait" node.
   • Adjust the Delay Time (in seconds) as needed. A delay of 5-10 seconds per message is a good starting point to prevent API rate limits.
6. Configure Limit Node (Node ID: 1237) - Optional:
   • By default, this node is not connected. If you want to limit the number of messages sent per run, connect it between "Google Sheets" and "Loop Over Items".
   • Configure the Limit property to the desired number of items.
7. Activate the Workflow:
   • Once all configurations are complete, save the workflow and activate it by toggling the "Active" switch in the top right corner of the n8n editor.

The workflow will now run according to your schedule, fetching contacts from Google Sheets and sending personalized WhatsApp messages with a delay between each message.