ubuntu-phone team mailing list archive

[Jan Kundrát <jkt@xxxxxxxxxx>]

On Tuesday, 26 March 2013 09:45:07 CEST, Matt Richardson wrote:
> You did say, however, that you would be wiling to accept patches for
> POP3 support if the contributor was also willing to maintain the patch.
> At the time I was not capable of doing so but I would be willing to look
> into it again now.

Hi Matt,
thanks for your interest. What I said last year is still valid -- if someone is willing to maintain the POP3 code and if its quality and design is good, it could be a good candidate for merging. This is a big if, though. 

Some users are apparently stuck on POP3, some of them for legacy reasons (their provider not supporting anything better), others for pure intertia ("I've always used that"). There is definitely some value in having the POP3 support, but it's going to be hard to do this properly.

There is a ton of technical problems with POP3:

- No support for server-side folders. In POP3, all you have is a view to a flat list of messages without any hierarchy.

- It is problematic to save the "sent" messages so that these are shared between multiple clients.

- No possibility to fetch messages partially -- if there is a 10MB e-mail, you have to download it in its eternity.

- No efficient way to "synchronize a mailbox". The UIDL command helps a bit, but is not sufficient because it's an optional extension and several messages are allowed to map to the same UID. If you intend to leave the messages on server, the future synchronizations are going to take longer and longer and transfer more and more data.

In short, the POP3 protocol lacks features which are critical once you are accessing mail from multiple devices or if the user has more than a couple hundreds of messages -- and I believe that at least the former is an extremely important use case for a client in your cell phone. Quite frankly, I believe that the only future-proof way is offering the users an IMAP proxy for accessing their legacy POP3-only mail store, perhaps as a commercial service.

It is important to know how you are going to approach the POP3 implementation -- I'm interested in details about that. Do you have a design document or some code available already?

With kind regards,
Jan

--
Trojitá, a fast Qt IMAP e-mail client -- http://trojita.flaska.net/