Disappearing plugins

If you have any application that adds buttons to the address book (like the contacts merger), you could have noticed that the buttons recently disappeared. This happened because of a bug in Monorail, the IM file transfer application.
Alban already fixed this bug and uploaded a new version to extras-devel. This new version also fixes other bugs, including a crash caused by the sharing plugin in Conboy.

Update: Note that you need to reboot or kill osso-addressbook after updating monorail to see the plugins again.

Contacts merger 0.1.3 in Maemo extras-testing

Since my previous post about the contacts merger, I fixed a crash, made it handle better broken vcards, improved the partial matching and made the installer quit the address book when the plugin is installed, so no reboot is needed.
The new 0.1.3 merger is now available in Maemo extras-testing, just look for “Merge your duplicate contacts” in the application manager.

What’s next

Suppose I could have some spare time to write some small applications relating to the N900 address book; what would you want me to work on? The application should be small and not require changes to the closed source components. Suggestions are welcome in the comments, but I cannot assure you anything :)

Update: I meant extras-testing of course, not extras

Finding duplicate contacts in your address book

One of the common complaints about the Maemo address book is that it’s easy to get a lot of duplicate contacts as the address book is able to pull your contacts from various IM services. From the beginning there has been a way to merge duplicates, but it meant manually going through all of your contacts hunting down the duplicates.
Today I finished writing the first version of a program that tries to automatically detect duplicates based on the IM names, emails, phone numbers and names. Of course this is just based on heuristics; you still have to go through the list and select the contacts that you want to merge. You can find this utility under the name “Merge your duplicate contacts” in the application manager and it’s available in Maemo extras-devel. Remember that extras-devel contains unstable software: enable it only if you really know what you are doing!
After installing Contacts Merger you have to reboot your phone[1] and then you will get a “Find duplicate contacts” button in the menu of the main address book window.

The window suggesting the possible merges
The window suggesting the possible merges

Update: I released 0.1.1 that fixes a crasher in case of malformed contacts.

Update 2: Forgot to say where to get the code.

[1] Sadly the address book doesn’t automatically load newly installed plugins without a restart; see bug #10542.

Plugins for the N900 address book

Finally the new update for Maemo 5 is out; it’s good to see that months of bug fixes and new features are finally available to everybody! One of the new features, not directly visible to users, is that developers can now add new buttons to the Contacts application menu. At the beginning we wanted to make the plugin system more powerful, but sadly it required too many changes and we didn’t have enough time to finish and test it properly.

A “Hello World” button added by the example plugin
A “Hello World” button added by the example plugin

To add new buttons you have to create a new object that derives from OssoABookMenuExtension and implements the required methods. For an example of this, see the example on gitorious that Mathias wrote and the API documentation.
Please, don’t go crazy with this new feature and don’t add 2000 different buttons to the menu!

Merge back your Facebook contacts

As I said in my previous blog post, some changes in the Facebook XMPP servers lead to the unmerging of the Facebook contacts that were merged with local contacts in the N900 address book. To fix this problem I wrote the small utility Facebook migrator, now available in Maemo extras-testing, that automatically merges back your contacts. Please remember that extras-testing contains unstable software and mine is not an exception! The source code is available on the Collabora git repositories.

If you have any feedback, please let me know in the comments to this post. The only known issue at the moment is that saving your contacts is quite slow, but I didn’t bother making it fast considering that it’s just a one time operation.

WordPress troubles

In other news, I noticed that I don’t get an email notification anymore when somebody comments on my blog, but a simple PHP script that uses the mail() function sends emails correctly. In the logs I don’t see anything useful and I’m sure the notifications are not in the spam folder. Does anybody have any suggestion on how to debug this?

Facebook and the N900 address book

The N900 address book can merge multiple contacts into a single entity: if you have a friend that has a phone number, an email address, a Jabber user name, a MSN one and so on, then you can merge all of the different entities into a single meta-contact.

Locally stored details and an IM user name in the same contact
Locally stored details and an IM user name in the same contact

The different IM contacts are tracked through their username and should be immutable[1], but yesterday Facebook changed all the IDs from something like “u123456789@chat.facebook.com” to “-123456789@chat.facebook.com”. For the address book this means that all the previous contacts were deleted from the IM roster and new contacts were added, so you get duplicate contacts. Moreover, when a contact is removed from the roster we leave the IM user name in the contact details, if you click the button you can add the contact back to one of your rosters. In the Facebook case this means that you end up with all of your meta-contacts with a useless button that cannot do nothing.

The fix for this is to remove the old IDs and merge your contacts again, simple but tedious. A better way to do it is to be patient and wait until I finish a program that will do it for you in a few click ;)

Update: I finished and release the program, see my blog post about Facebook migrator.

[1] Actually, some changes in the IDs are possible for normalisation purposes; if you add “FooBar@example.COM” it will become “foobar@example.com” in your roster. (And yes, the normalisation is buggy in PR1.1, but it will be fixed in PR1.2.)

GTK surprises on Maemo

Sometimes the creation of the contact chooser used on the N900 can be slow so, using callgrind and kcachegrind, I tried to understand what is the source of the slowness. This lead me to find some unexpected, and apparently undocumented, differences between upstream GTK and the Maemo version.

The Maemo 5 contact chooser
The Maemo 5 contact chooser

The widget contains a GtkTreeView that uses a model with just one column for the contact objects. How can its creation be so slow? To my surprise most of the time was spent decompressing the avatar images!
The avatars of the contacts are loaded, scaled and cropped in the cell data function of the GtkTreeViewColumn as, for various reasons, we cannot cache on disk the resulting image or generate it before the creation of the widget. Following calls of the cell data function for the same row won’t need to generate the avatar anymore. Doing non-trivial operations in the cell data function is not the nicest thing to do, but this should not be a problem as the cell data function is called only for the visible rows, right? No, at least not on Maemo!
To verify it just try this example program: on Maemo the cell_func() function is called once per item in the model plus once per visible item, elsewhere only once per visible item.

After a bit of investigation together with Claudio, we discovered that on Maemo there is a function called gtk_&#8203tree_&#8203view_&#8203column_&#8203get_&#8203cell_&#8203data_&#8203hint() that returns GTK_&#8203TREE_&#8203CELL_&#8203DATA_&#8203HINT_&#8203KEY_&#8203FOCUS, GTK_&#8203TREE_&#8203CELL_&#8203DATA_&#8203HINT_&#8203SENSITIVITY or GTK_&#8203TREE_&#8203CELL_&#8203DATA_&#8203HINT_&#8203ALL. The hint tells you why the function was called; in the example code the function is called on the hidden rows only to get their sensitivity so there is no need to set the “pixbuf” property of the cell at this point.

Just this tiny change in the address book code makes the contact chooser open much faster if you have a lot of contacts with big avatars, like the ones that Hermes creates. On the other hand the delayed loading made the scrolling become non-smooth :(
To fix the scrolling I had to implement some asynchronous loading of the avatars. The contact chooser now tries to load as many avatars as possible in idle moments and also tries to load first the avatars for the contacts that the user is more likely to see. The results seem quite good; now the contact list is fast, scrolling is smooth and the delayed loading of avatars should not be visible in normal cases.


During the Christmas holidays I managed to find some time to write a couple of small programs related to the address book on the N900; they are nothing too fancy (no UI, no proper packaging, not the best code quality, etc.) as I wrote them for my personal use, but I still think it could be useful to share them with other people.

The one I’m talking about today is a simple command-line utility that adds an email address to your contacts based on the Jabber ID (or on the ID of other protocols). This is very useful to me as in Collabora we all have a roster automatically filled with the other Collaborans, this way I can automatically have their email addresses in my address book.

This cannot be done automatically for all the contact as, usually, it’s not true that a Jabber ID is also a valid email address (for instance it’s not true for jabber.org users), but it’s true at least for the GMail and Collabora servers.

If you want to try jid-to-email get the already compiled arm executable or the source code. Remember to take a backup before trying it, I don’t want to be blamed if something goes horribly wrong ;).

The program accepts two arguments: the vcard field for the IM protocol and a regular expression. For instance, if you cd to the directory where the program is and do “./jid-to-email X-JABBER @collabora.co.uk”, an email address will be added to all the contacts that have a Jabber ID containing “@collabora.co.uk”. Similarly “./jid-to-email X-JABBER ‘@g(oogle)?mail.com’” will add an email address to all the contacts with a Jabber ID containing “@gmail.com” or “@googlemail.com”. You could also try using “X-MSN” to do the same thing for contacts that use their GMail address as MSN ID.

Please, let me know if you know any other server where the Jabber ID is always a valid email address.

By the way, this week-end I’m going to Brussels for FOSDEM: hope to meet a lot of GNOME people there!

I'm going to FOSDEM, the Free and Open Source Software Developers' European Meeting

Contacts on Maemo

After the Maemo Summit the details on the address book application and framework in Maemo 5 are finally completely public so I can openly talk about what I worked on during the past year and, even better, I actually have a smartphone that runs this software! (Thanks to Nokia that gave out 300 N900s, but I will talk about this in my next post)

Contacts on the N900
Contacts on the N900

Contact details
Contact details

As you can see from the screenshots, the Contacts application has everything you would expect from a normal phone address book but it also tightly integrates IM. Your local, Jabber/GTalk and Skype contacts will appear in the same address book and, if you have a friend on multiple IM protocols, you can easily merge all the contacts into a single entity.

My main task has been making the component responsible for the IM part of the address book work properly, this component is an evolution-data-server backend (recently released under LGPL) that acts as a bridge between the Telepathy IM framework and evolution-data-server. See the README file for more details.
Sadly the library on top of evolution-data-server that does the magic contact merging and contains the widgets used on Maemo is not open, but there is some hope for it.

Address book components
Address book components

At the Maemo Summit I also gave a talk on Telepathy and how it’s used on Maemo, both for messaging/VOIP and for the contacts integration. The slides are available in PDF or in OpenOffice.org format (but for some reason colours look wrong in some recent versions of OpenOffice).