mailpit-integration

Test emails locally by routing SMTP traffic through a Mailpit container in your .NET Aspire AppHost, which captures all messages for inspection without performing actual delivery. This allows you to verify rendering, headers, and delivery flows safely during development.

Yes, you can inspect email headers and HTML rendering during Aspire integration tests by connecting your application to the Mailpit SMTP endpoint, which captures the messages and provides a UI to view rendered HTML, headers, and attachments.

To set up local SMTP integration testing, you need a running Mailpit container, Aspire AppHost configuration to route the SMTP traffic, and test patterns that connect your application to the Mailpit SMTP endpoint to capture emails.

The best way to capture SMTP traffic in an Aspire project is to configure a Mailpit container in the AppHost, routing all outgoing emails to Mailpit so you can validate end-to-end email flows without sending real mail.

Mailpit works with ASP.NET integration tests by acting as a local SMTP server that intercepts and captures emails, allowing you to verify end-to-end email delivery flows, rendering, and headers without sending real messages.

Use Mailpit instead of a real SMTP server for local email testing to prevent accidental delivery of real emails while still capturing and inspecting all SMTP traffic, including rendered HTML, headers, and attachments in a local UI.