SPF and DKIM Results in ActionMailbox

Hi everyone,

We’re working on a feature that makes use of actionmailbox and one of the things we wanted to do for security purposes is check that the inbound email passes an SPF/DKIM validation. Our ingress service - sendgrid - does this automatically and passes the result along in the payload that hits the InboundEmailController but it isn’t passed along to the Mail::Message object.

While researching this I saw that someone had previously added the X-Original-To header to the sendgrid controller and thought it might be useful to follow a similar pattern to pass along the SPF and DKIM results.

I have a working patch for this in our project but if there’s interest in this I’d be happy to push a PR with it. Would love any thoughts.