n8n Workflow: Send Emails via Gmail from Obsidian

This n8n workflow provides a robust system for sending emails through Gmail, triggered by a webhook. It includes advanced features for handling multiple recipients, attachments, and dynamic content, making it ideal for integrating with tools like Obsidian for structured email dispatch.

What it does

This workflow streamlines the process of sending emails by:

1. Listening for a Webhook Trigger: It starts by receiving data via a webhook, which typically contains email details such as recipients, subject, body, and optional attachments.
2. Processing Multiple Recipients: It intelligently handles multiple email addresses for the "To", "Cc", and "Bcc" fields, splitting them into individual items for processing.
3. Preparing Attachments: If attachment data is provided (e.g., Base64 encoded files), it converts them into a format suitable for email attachments.
4. Looping Through Recipients: It iterates over each recipient, allowing for personalized email content or individual sending if needed.
5. Setting Email Fields: It dynamically sets the email's subject, body, and recipient addresses based on the incoming webhook data.
6. Sending Email via Gmail: It sends the prepared email using a configured Gmail account.
7. Responding to Webhook: After processing, it sends a response back to the triggering system, indicating success or failure.

Prerequisites/Requirements

• n8n Instance: A running instance of n8n.
• Gmail Account: A Gmail account configured as a credential within n8n. This will be used to send the emails.
• Source System with Webhook Capability: A system capable of sending HTTP POST requests to a webhook URL (e.g., Obsidian, a custom script, another n8n workflow).

Setup/Usage

1. Import the Workflow:

   • Copy the provided JSON workflow.
   • In your n8n instance, go to "Workflows" and click "New".
   • Click the "Import from JSON" button (usually a cloud icon with an arrow pointing down) and paste the JSON.

2. Configure Gmail Credentials:

   • Locate the "Gmail" node in the workflow.
   • Click on the "Credential" field and select an existing Gmail OAuth2 credential or create a new one. Follow the n8n documentation for setting up Gmail OAuth2 credentials if you need to create a new one.

3. Activate the Webhook:

   • Locate the "Webhook" node.
   • Copy the "Webhook URL" displayed in the node's settings. This is the URL you will send your email data to.
   • Ensure the workflow is "Active" (toggle the switch in the top right corner of the n8n canvas).

4. Send Data to the Webhook:

   • Send an HTTP POST request to the copied Webhook URL.
   • The request body should be JSON and contain the email details. Here's an example structure:

   {
     "to": "recipient1@example.com, recipient2@example.com",
     "cc": "cc_recipient@example.com",
     "bcc": "",
     "subject": "Email Subject from Obsidian",
     "body": "This is the email body sent from Obsidian via n8n.\n\nBest regards,\nYour Name",
     "attachments": [
       {
         "fileName": "document.pdf",
         "fileContent": "JVBERi0xLjQKJcOkw7z...[Base64 encoded PDF content]..."
       }
     ]
   }
   

   • to, cc, bcc: Can be single email addresses or comma-separated lists.
   • subject: The subject line of the email.
   • body: The main content of the email.
   • attachments: An optional array of attachment objects. Each object should have a fileName and fileContent (Base64 encoded string of the file).

This setup allows you to trigger email sending from any application that can send a webhook, such as a custom script in Obsidian or other automation tools, leveraging Gmail's sending capabilities.