How to forward emails only for specific domains?

[jeffwidman]

I use the same SparkPost account across multiple websites.

One of these is a Xenforo forum, which supports cleaning the email list by parsing bounces out of a mailbox.

For this, and this site only, I want to use this Heroku app to forward bounces. But for email sent by the other sites, I don't want those bounces to be forwarded.

How do I select only that domain for this app?

Or can I use Subaccounts for this? Although looks like the Subaccount docs say can't use them with Heroku.

[orval]

To add that functionality you would need to fork this sample app and modify the logic in index.js to ignore whichever domains you don't want.

[jeffwidman]

I saw that the setup for the app includes specifying the "FROM" email address... since I use different email addresses for each domain, will that not work as a way to distinguish between them?

Or am I misunderstanding what that is used for?

[orval]

The FORWARD_FROM address must use a verified sending domain like any other message one sends through SparkPost.

You should be able to do what you want by modifying the code to filter based on eventData.routing_domain.