Monthly Archives: December 2011

WebKitGTK+ Hackfest: WK2, a11y and Ephiphany’s ad blocker extension

Published / by mario

Some posts have been already published about this during the last days, but just in case you missed them I will mention it here again: Last week, a bunch of hackers gathered together in the Igalia office in Coruña for the third edition of the WebKitGTK+ hackfest , and a lot of work has been done, as Juanjo has already summarized in his “WebKitGTK+ hackfest wrap up” post.

WebKitGTK+ 2011 Hackfest

So, as everything has been already said from a more general perspective, I’d like to write my very personal wrap up here, focused on the tasks that I’ve been working on, which can be summarized in three:

  • Enabling accessibility support in WebKit2GTK+.
  • Rewrite of the Ad Blocker extension for Epiphany.
  • Bug fixing in WebKitGTK+‘s accessibility related code.

Enabling accessibility support in WebKit2GTK+

This has been, by far, the task I devoted most of the time to during the hackfest, mainly focused on writing a ‘feature complete’ patch that could be applied upstream, and thus that could be reviewed in first place. But, what do I mean by “a ‘feature complete’ patch”? Well, perhaps you are already aware of the initial results already got in the WebKit2GTK+ a11y realm, but those results were obtained with a patch still in a very early state and, among other things, lacking a very important requirement for getting it accepted upstream: tests.

Fortunately, I can now proudly say that I managed to find a good way to write those tests (specially tricky due to the multiprocess architecture of WebKit2) and that there shouldn’t be any problem either with getting them work properly in the buildbots, which was something I was quite concerned about by the begining of the week, to be honest.

Besides the tests, the other obvious problem was that such a patch was not widely tested yet with the Orca screen reader (I use Accerciser for development purposes most of the time), and that would for sure unveil issues that would need fixing before being really able to propose a patch for reviewing, and so that was the other aspect where I put the spotlight during this week.

And regarding to this, I have to say that Joanmarie Diggs was working tirelessly by testing Orca with my WebKit2GTK+ a11y patch, reporting bugs, and helping me a lot to prioritize the tasks that would need to be done. From all those, I mainly worked this week in the following ones:

  • Emitting the AtkDocument’s signals (‘load-complete’, ‘load-stopped’ and ‘reload’), which was working only in WebKitGTK+ but not in WebKit2GTK+. See the bug report and the patch (still pending on review) for this issue in bug 73750. Also, I reported and worked for a while in another bug related to this, which is now already fixed upstream (see bug 73746). Yay!
  • Ensure that the accessibility hierarchy doesn’t break when (re)loading, which was causing that Orca stopped speaking unless it “manually” drilled down the full a11y hierarchy after the (re)load. I finally fixed that issue yesterday and integrated it in the patch for enabling a11y support in WebKit2GTK+, now already attached and pending on review along with bug 72589.

So, the conclusion of this part would be that we have now a patch in WebKit’s bugzilla (see bug 72589) that, once it’s approved, would enable accessibility in WebKit2GTK+ once and for all. Of course, this will probably take some time before it gets accepted upstream, but it’s yet another nice milestone in my opinion, and I personally hope it would happen on time for GNOME 3.4. Time will tell, though.

Rewrite of the Ad Blocker extension for Epiphany

This was another thing I’ve been randomly working on since some time ago (whenever “spare” time permitted), and that I was able to advance quite a lot right after coming back from the parental leave I enjoyed on September (did I say my second child was born on August the 30th?). However, the patch was not finished by any means, and some issues kindly pointed by Xan in bugzilla needed fixing before being able to say aloud something like “hey, the new ad blocker is now in town!”.

Thus, we thought it would be good to devote some time during the hackfest to try to close this task too, so we did: Xan reviewed the new version of the patch (addressing the issues he previously pointed out), I made some last changes based on that new feedback from him and we finally pushed it to the repository, replacing the old ad blocker extension with this new one, which is based in Midori‘s ad blocker and so is compatible with Adblock Plus filters, which work very well IMHO.

So, this basically means that the new ad blocker extension will be present from Epiphany 3.4 on. Check out the related bug in GNOME‘s bugzilla: bug 660154

Bug fixing in WebKitGTK+’s accessibility related code

Besides working in the WebKit2GTK+ a11y realm and on finishing the new ad blocker extension, I’ve also spent some time (although not as much as I would have wanted) fixing regressions in WebKitGTK+‘s a11y code as reported by Joanie (basically bug 72804 and bug 72830).

Compared to the other two points, this has been of course a pretty small contribution, but worth doing anyway since they were very important for Orca to work properly with WebKitGTK+ based browsers (special mention to bug 72830 here).

Conclusion

From the work-related point of view, I’d say this hackfest has been highly productive in general, as we achieved many goals which, as Juanjo pointed out in his wrap up post, “were not mainly about fixing critical and blocker bugs and implementing basic missing features, but about more ambitious and challenging” ones. As for me, I’m pretty happy with the results I got, specially with the WK2 a11y patch, which has now a much better shape, and so I hope we can integrate it soon upstream.

And from a more personal point of view, I’d like to say I had a great time (again!) this year in the hackfest, and not only because of the achiements got, but also because I had quite a lot of fun as well, because I met new people and because I felt, more than ever, part of a community and a project which I love.

To finish, I’d just like to mention that I’ve been taking some pictures during the hackfest, which you can check out in this photo set in flickr (pictures uploaded with Frogr, of course!). Nayan has also taken some pictures as well, check them out here.

WebKitGTK+ 2011 Hackfest (The End)

Of course, thanks a lot to the sponsors that made this possible: Collabora, Motorola, Igalia and the always awesome GNOME Foundation. I hope we’ll be able to repeat it next year, since this hackfest it’s only getting more and more awesome every time it happens.