Tracker in Summer

Lots of effort is going into Tracker at the moment. I was waiting for a convenient time to blog about it all, but there isn’t a convenient moment on a project like this, just lots of interesting tasks all blocked on different things.

App porting

With the API changes mostly nailed down, our focus moved to making initial Tracker 3 ports of the libraries and apps that use Tracker. This is a crucial step to prove that the new design works as we expect, and has helped us to find and fix loads of rough edges. We want to work with the maintainers of each app to finish off these ports.

If you want to help, or just follow along with the app porting, the process is being tracked in this GNOME Initiatives issue.

The biggest success story so far is GNOME Music. The maintainers Jean and Marinus are regular collaborators in #tracker and in our video meetings, and we’ve already got a (mostly) working port to Tracker 3. You can download a Flatpak build from that merge request, but note that it requires tracker-miners 3.0 installed on your host.

We’re hoping we can work around the host dependency in most cases, but I got excited and made unofficial Fedora packages of Tracker 3 which allowed me to try it out on my laptop.

We are also happy that GTK can be built against Tracker 3 already, and excited for the work in progress on Rygel. At the time of writing, the other apps with Tracker 3 work in progress Boxes, Files, Notes, Photos, Videos. Some of these use the new tracker3 Grilo plugin which we hope a Grilo maintainer will be able to review and merge soon. All help with finishing these branches and the remaining apps will be very welcome.

Release strategy

We have been putting thought into how to release Tracker 3. We need collaboration on two sides: from app maintainers who we need to volunteer their time and energy to review, test and merge the Tracker 3 changes in their apps, and from distros who we need to volunteer their time to package the new version and release it.

We have some tricky puzzles to solve, the main one being how an app might switch to Tracker 3 without breaking on Ubuntu 20.04 and other distros that are unlikely to include Tracker 3, but are likely to host the latest Flatpak apps.

We are hoping to find a path forward that satisfies everyone, again, you can follow the discussion in Initiative issue #17.

As you can see, we are volunteering a lot of our time at the moment to make sure this complicated project is a success.

Data exporting

We made it more convenient to export data from Tracker databases, with the tracker export command. It’s nice to have a quick way to see exactly what is stored there. This feature will also be crucial for exporting app data such as photo albums and starred files from the centralized Tracker 2 database.

Hardware testing with umockdev

The removable device support in Tracker goes largely untested, because you need to actually plug and unplug a real USB to exercise it. As always, for a volunteer driven project like Tracker it’s vital that testing the code is as easy as possible.

I recently discovered umockdev and decided to give it a spin. I started with the power management code because it’s super simple – on low battery notication, we stop the indexer. I’m happy with the test code but unfortunately it fails on GNOME’s CI runners with an error from umockdev:

sendmsg_one: cannot connect to client's event socket: Permission denied

I’m not sure when I’ll be motived to dig into why this fails, since the problem only reproduces on the CI runners, so if anyone has a pointer on what’s wrong then please comment on the MR.

GUADEC

Due to the COVID-19 pandemic, GUADEC will be an online event but Tracker will be covered in two talks, “Tracker: The Future is Present” on the Friday, and my talk “Move Fast and Break Things” on Thursday.

The pandemic also means I’m likely to be spending the whole summer here in Galicia which can hardly be seen as bad luck. Here’s a photo of a beautiful spot I discovered recently about 30km from where I live:

Next steps

Carlos is working on some final API tweaks before we make another Tracker 2.99 beta release, after which the API should be fully stable. The Flatpak portal is also nearly ready.

We hope to see progress with app ports. This depends more and more on when app developers can volunteer their time to collaborate with us. Progress in the next few weeks will decide whether we target GNOME 3.38 (September 2020) or GNOME 3.40 (March 2021) for switching everything over to Tracker 3.

Unlike GTK 4, I can’t show any cool screenshots. I do have some ideas about how to demonstrate the improvements over Tracker 2, however … watch this space!

As always, we are available on IRC/Matrix in #tracker and you are welcome to join our online meetings.