How to manage answers directly on email notifications

Question

I would like to know what's the best way to manage answers to email notifications.

eg. The user receive an email notification, and instead of having to click on a link to go on the website and answer it he could directly reply to the email.

Answer 1

Use the Message-ID header field to uniquely identify each message. If there is a reply on that message, the client should put that message ID in the In-Reply-To header field in the reply message. See RFC 2822 for further details.

Answer 2

There's no best way. Depending on what you want to do with the responses, you could as well handle them with thunderbirds message filters ;) .

Put a unique identifier into the subject or the body of the notification that you're sending so that you can identify & classify the email correctly when a user replies by email.

If you want to stick with php: pick up the php pop3 client class from: http://www.phpclasses.org/browse/package/2.html or find a client elsewhere and then just parse your message responses and classify / handle them however you want to.

Answer 3

Stick an id and authentication token in the subject line.

Pipe it into a script that can process it with Procmail

Answer 4

As a learning exercise you could read the php code and Documentation to the drupal module http://drupal.org/project/mailhandler mail handler. This accepts emails and looks for script like instructions.

The answer above about checking the message id is also very valid.