Report #3 - Google Tasks API support to libgdata/Evolution - compiling, testing and believing

Again after longer pause there's some status update about Google Tasks support in libgdata/Evolution. We got all August past us, and there have been some good news and surprises along the way, so it's worth to blog about it.

First, in a crazy travel stunt which included traveling in the car non-stop for 18 hours to and back with only one driver, my friend Rudolfs Mazurs (and our significant ones) in torching 37C hotness in a car without conditioning, we went to first GUADEC in my life in Brno. As I had to miss first two days due of theatre performance I had to do on Friday, we arrived at Saturday's evening. After regrouping at dormitories and arriving late at conference place Faculty of Information Technology at the Brno University of Technology, we met Gstreamer's crowd - Transmageddon hacker and unofficial leader of sorts Christian Schaller, my past year's mentor and current de facto maintainer Sebastian Dröge and other Gstreamer core guys with addition of Zeeshan Ali of Boxes and Maps fame, and went for hunting food. For driving 18 hours without sleep it was nice ending of the day, with chats going around about beautifully geeky stuff like Doctor Who.

Last day consisted of lot of interesting speeches, I missed Sunday's keynote, but got essence of it later from buzz and back at home watching it in recording. I attended such good presentations like provocative and excellent Stef Walter's "More secure with less "security"", or nicely expressed Jeff Fortin's "Pitiv and GES, towards 1.x", which included most precise video clip explaining migration from Gstreamer 0.10 to 1.0 and bug hunting involved ever (yeah, that was *that* bad :)).

In the middle of all this I also attended Evolution hackfest and met and had a chat with my mentors libgdata maintainer Philip Whitnall and Evolution superhacker Milan Crha. Unfortunately due of sudden changes in planning - and willing to avoid driving back in a deadly heat during daytime, so in result we decided to leave on Monday's evening, not Tuesday as planned - my visit was cut short. Overall GUADEC was a blast, and I really enjoyed it even for such short visit.

I started to work on libgdata testing during GUADEC, and as usual ran into several interesting things. First of all, when Google recommends you something when using their APIs and products, you better use it, because trying other kinda "supported" things will yield inconsistent results. In this case for new JSON based APIs Google "recommends" to use OAuth2. In result with one week of trial and error I settled for using GNOME Online Accounts as way to build Authorizer (using a GDataGoaAuthorizer subclass), which I need to build working Service object (in this case GDataTasksService) so I can check if things are really working as they should. That included modifying GOA code for including Google Tasks authorization scope in get_scope method of GoaGoogleProvider, and building it with separated application keys using --with-google-client-id and --with-google-client-secret configure flags (I needed them because you have to enable tasks support for your application in Google API Console, it's not done yet for GNOME application, which is managed by Debarshi 'Rishi' Ray). In result I had my own GOA daemon, which I run instead of system's installed. I also replaced several symlinks to libgoa and libgoabackend libraries as I installed goa in /opt. Now I was ready to run the tests.

Getting my own code to actual testing was kinda fun, because I learned a lot. While I'm not totally new to C and Glib, there's still lot of things for me to learn. It was most rewarding thing too, because to see it actually working after long session of debugging and compiling is very uplifting moment.

While I was testing GDataTasks code Philip started to merge my core libgdata improvements (along with his own additions) to include in special branch and after 0.14 release - in master. Currently my plan for next week is to complete libgdata Google Tasks support by finishing insert/delete/update methods to GDataTasksService for both tasks and tasklists. Before that though I will rebase my work on Github on newest version of master as it include all JSON I need already.

On Wednesday I will blog about EDS aka Evolution data server changes, and what else I will need to have actually working Google Tasks support in Evolution. My GitHub branch for libgdata can be find here and for evolution-data server here.