[BUG] Attachments were deleted in archive

[schmidtch89]

Version

Which version are you using?
0.3.7

Steps to Reproduce

I initialized an archive from my mailbox in bichon. After that I deleted an attachment from an email and it also disappeared from my archive.

Issue Description

What is the problem you encountered?
A mailarchive should not delete any data from the original mail. I also deleted already archived mails in my mailbox and they still existed in my archive. So this verifies that the behaviour is not expected.

[rustmailer]

@schmidtch89
It appears that when an attachment is removed, some IMAP servers change the UID while keeping the Message-ID identical.

Since Bichon uses the UID to track changes but relies on the Message-ID for deduplication, this specific server behavior likely causes the original archived mail to be overwritten or deleted unexpectedly.

[schmidtch89]

So we need to find a workaround as we can´t solve the root cause.
I am not an expert to this topic but if the app would rely on the UID for deduplication this would cause duplicate mails if the attachment changes, right?
At the moment I am not aware about a solution for this issue. Removing mailboxes from deduplication via UI could solve the problem but the user must be aware about the bahaviour of his mailserver or the mailserver of his mailprovider.

Just to clear that: Bichon will never delete mailf from the mailserver if there is a change on the mail itself or the mail is deleted in the mailservers inbox, correct?

[rustmailer]

@schmidtch89
Bichon follows a one-way sync principle and won't delete anything from your inbox.

I’m currently planning attachment-level deduplication as a workaround. By separating attachments from the mail body, we can maintain consistency regardless of how the mail server handles UIDs.

[schmidtch89]

@rustmailer
Thank you for the quick answer. That would be a much better fix than my thoughts I had about this topic.
Good luck and thank you for taking care of it.