So I spent a chunk of time over the last day or so looking at prior art – the efforts of others to solve the same problem. (I’m using “prior art” pretty loosely. I’m not by any means filing patent claims.)
Prior Art Round-up
The Hedera Project
Hedera is a Thunderbird extension, and probably the most direct solution to the Thunderbird and Ubuntu One integration problem. With Hedera, all contacts in all address books are sent off to Ubuntu One, with metadata to keep the contacts in the right address books. Metadata is also included to keep contacts distinct from one Thunderbird profile to the next (if you’re one of the rare users of profiles).
As of late, the extension has gotten a bit dusty – the author, James Tait, is currently working at Canonical, and hasn’t had much time to maintain it.
Despite that, it still does the job pretty well. I was successfully able to synchronize my contacts to Ubuntu One, which made me fist-pump. Great work, James!
However, after examining the code, I have a few concerns:
- The first one that jumps out at me is the reliance upon a shell script to determine the DesktopCouch server port, as well as obtain access credentials. While effective, I think a more direct approach would be more appropriate. Perhaps I could develop a DesktopCouch XPCOM service that returns these values?
- Contacts that are not branded with “Thunderbird” metadata are ignored. This means that contacts created from the Ubuntu One web interface are not brought into Thunderbird, unless the metadata can somehow be added there. I didn’t immediately see a way to do this. This also means that contacts from other applications (I’m looking at you, Evolution) don’t get brought into Thunderbird.
- Since the contacts are also given profile metadata, it means that I only get those contacts if I share the same profile. This is problematic if I drop my computer in the river, get a new one, and fire up a copy of Thunderbird: my profile will be different, so my contacts won’t come in. They’ll still exist in Ubuntu One’s storage, but won’t come into my Thunderbird profile, unless I modify my profile string to match my old one.
Funambol Mozilla Sync Client
Funambol develops open-source mobile communications sync software, and it looks like Canonical is using Funambol to power their mobile sync services.
Users install the Funambol Mozilla Sync Client, which then syncs contacts with Ubuntu One over the mobile sync service.
It’s not a bad solution, and is the one advocated by the Ubuntu Support pages.
Here are my concerns:
- According to the support pages, only Thunderbird 2.x is currently supported. Thunderbird 3.1.9 is the current version in the Ubuntu packages, and the Mozilla Messaging team is working like crazy people on 3.3 (where did 3.2 go? long story). Supporting Thunderbird 3 is a BFD.
- This approach assumes that you’ve got the $3.99 US per month mobile Ubuntu One service.
Now, with respect to that last point, I’m not against paying for stuff. Money lets companies like Canonical, Funambol (and Mozilla Messaging, for that matter) survive. But I do think it’s a little silly that Thunderbird needs to pretend to be a mobile phone, and communicate through the mobile sync service. That’s why I said Hedera was the more direct solution.
If I got any of that wrong, I’m sure someone from Funambol will comment and correct me.
Bindwood is an extension that allows Mozilla Firefox to synchronize bookmarks via Ubuntu One. The reason I’m putting this up, is because a lot of good code has been written here to communicate with the DesktopCouch service. If I resolve a few licensing issues, it might be possible for me to leverage some of that code to make the Thunderbird + Ubuntu One project move faster.
Evolution-CouchDB creates a new address book called “Ubuntu One” for every user. Any contacts that go into that address book are sync’d with Ubuntu One, and any contacts that get added to Ubuntu One get loaded into that address book.
It’s an elegant solution, and addresses the issues I brought up with Hedera.
If I were to implement a similar solution for Thunderbird, it would mean that contacts between Evolution would be seamlessly imported into Thunderbird. The behaviour would be exactly the same. Consistency is good. Consistency means happy users.
Unless I hear compelling argument for something else, I think this the behaviour I’m going to implement.
Mac OSX’s Address Book
Mac OSX has it’s own internal address book, and many Mac-based Thunderbird users were crying out for integration. A developer named Peter Van der Beken karate-kicked the bug (and may have collected a bug bounty on it…unsure), and now we have OSX address book integration.
The OSX address book integration is very similar to Evolution’s behaviour: it creates a new address book within Thunderbird, and all contacts from the OSX native address book appear there.
As it stands, this integration is read-only.
Since we’re dealing with OSX, it means Objective-C is the name of the game. Here’s the code.
Except for one thing.
I spent most of yesterday examining this one, and I think I’ve got my head wrapped around it.
So, RDF stands for Resource Description Framework, and it’s a way of representing information in a way so that machines can make useful inferences and queries about that information. That’s a super-simplified definition. Here’s something a little more robust.
What does this have to do with Thunderbird and Ubuntu One?
Well, it turns out that the Thunderbird address book interface uses RDF to query / know about the address books that are available. So, when you pop open the address book manager in Thunderbird, and it populates the list of address books, it’s using RDF to get that information.
So what’s wrong with that? Well, it means that if I want to add a special “Ubuntu One” address book, it has to register itself with the RDF service as an RDFResource.
There’s two issues there:
- Part of RDFResource is not scriptable, which means it’d need to be implemented in C++. So much for leveraging Bindwood / Hedera / Funambol.
- The Thunderbird team knows about the limitations of RDF and are trying to remove it’s usage from Thunderbird. I’d hate to implement all that RDFResource stuff just so it can get tossed out in a few months.
So I might have to really start pushing on RDF removal from the address book. If I go that route, it means that Ubuntu One synchronization would not be available for anything earlier than Thunderbird 3.3. Ugh.
Sounds like it’s time for me to discuss this with my superiors. I’ll let you know what I find out.