Email workers guide?

Developers Workers
1

Hello,

Is there a guide on email workers? I tried to connect to the email workers playground, but it gives me connection errors. I’m trying to do what I think should be pretty simple. I have a list of email aliases. In the email worker, depending on the email alias receiving an email, I would like to assign it a custom list-id header before the email is forwarded. Thanks

3
4

Thanks, but is there documentation somewhere on how to manipulate email headers? The Cloudflare workers docs seem to be http specific. But I may have missed something

5

You can pass some custom headers in the message.forward method: Runtime API · Cloudflare Email Routing docs
One slight issue if your goal is to modify the list-id:

If you want, you can add extra headers to the email message. Only X-* headers are allowed.

If you wanted to modify other headers, as far as I know your only option would be to send the email another way, potentially using the send_email binding, or some third party service: Send emails from Workers · Cloudflare Email Routing docs, but that would also require changing the sender.