Appstream has had a long history of getting its very sensible features into the hands of users. It’s an XML format which describes applications so that projects such as KDE can ship files with their apps which give a name, description, translations of this and pretty screenshots.
The first step is getting the Appstream metainfo files into the applications. KDE has this in many places but not all, if you spot an application please add one. It’s been supported in Extra CMake Modules for a while but the install directly changed recently just to confuse matters.
Then your archive has to extract the appstream files, in Neon we use Appstream Generator written by the Appstream master Matthias Klumpp and Harald set up some time ago but it broke last month. That meant we had to update to a new version so Scarlett had to add a load of new packages to Neon to get Appstream Generator to build and I had to work out how to debug D to convince it to work. Then we moved our archive to a new server for space and because it was fun so parts of the job which runs it had to been rewritten to work remotely. Finally there’s a pesky bug which means it looks at the oldest package not the newest one so any problems with the Appstream files stay around forever. So for now I deleted old packages.
So at least you can install Minuet from Discover, it gained an appstream file back in 16.04 but it was broken so we had to wait for 16.08 to get a working one.
But wait, this infrastructure for package managers is fiddly. Discover is showing the most popular installed app as Dilbert cartoons, which makes no sense. Turns out the popcon data for applications is made using fancy Docker scripts on an obscure server we’ve largely forgotten about but Cron doesn’t like Docker and doesn’t let it output anything when running even though the same command works fine when run manually. So I regenerated the popcon data manually in the hope we can work out how to cron it later on. And finally Discover is back showing popular apps and all the latest ones at that. Sorry for the delay folks.
Getting it to work in Neon developer editions is future work I fear.by