Set up a webhook in PowerMTA

Setting up a webhook in PowerMTA allows you to receive real-time event notifications related to email delivery. Let’s walk through the steps to set up a webhook:

PowerMTA Transmissions API

  • The Transmissions API enables you to submit emails for delivery via HTTP. Instead of using an SMTP client library, you can create a JSON object and post it to a URL.
  • Here’s how to use the Transmissions API:
    • Create an Email: Assemble your email content (headers, subject, text, HTML) and encode it according to MIME standards.
    • Submit via API: Post the pre-built email JSON object to the Transmissions API endpoint.
  • Note that PowerMTA expects the email to be already encoded for transmission, so you need to handle transfer encoding and MIME formatting.

PowerMTA Accounting Webhook

  • The Accounting webhook allows you to push event data (e.g., bounces, complaints) to a web application.
  • Key features of the Accounting webhook:
    • Event Data: Receive data related to email events (receptions, deferrals, deliveries, bounces, complaints).
    • Batched Posts: Events are posted as newline-delimited JSON or CSV batches.
    • Retries: If errors occur during posting, the webhook retries the batch.
  • Similar to event webhooks provided by SMTP delivery service providers.

Configuration of HTTP APIs

  • Setting up the HTTP APIs is straightforward and explained in the PowerMTA User’s Guide.
  • If you need HTTPS, consider setting up a validating certificate from Let’s Encrypt for endpoints and CA certificates for webhooks.

Remember that webhooks enhance your email delivery infrastructure by providing real-time insights and enabling seamless integration with other systems. Choose the integration method that aligns best with your organization’s goals and technical capabilities. 🚀

For more detailed implementation instructions, you can refer to the Postmastery article on HTTP-based APIs and webhooks in PowerMTA 5.0. Additionally, there’s an open-source PowerMTA Email API project on GitHub that demonstrates submitting emails to PowerMTA using HTTP and JSON. 📨