Hook to filter email notification message

A client requires us to encrypt a couple secure forms of theirs using PGP, and I'm actively seeking a way of hooking into the notifications and encrypting the notification message.

I can't seem to find a hook that has the notification object that would allow me to edit it. The Pre Submission hook contains the object but only contains {all fields} or some such as the content. Is there a hook for me to change this data as the notification message after the message has been populated but before it is sent?

Hi Carl,

Thanks for the quick response.

We want to encrypt the entire message.

Fairly proficient, I can handle the encryption part using PHP's GnuPG library. I'd like to find a hook after gravity form does it's parsing magic of filling the form data, but before it gets sent. Barring that, I can probably just build the form from scratch (Assuming my changes in pre_submission_filter don't get overwritten later in the process). I'd rather not do extra work, and if they add fields to the form later that would require me changing code each time. :(

I've been meaning to look through the source code and take a look but it's been a busy day. :)

Great, thank you so much, Carl!

Hey guys - I have a client who has a similar request. They'd like to have all data fields encrypted in an email message. How are Gravity Forms developers doing this?