[AppStream] Using AppStream for "Server Applications", Cockpit

[Richard Hughes]

On 29 March 2017 at 16:24, Marius Vollmer <marius.vollmer at redhat.com> wrote:
> and one of the ideas is to use AppStream.

I think that's a good idea.

>  - This would probably mean adding type="server-application" to the
>    spec.  Any issues with that?

I don't think so, but I'm not sure about the name. What would the
formal definition of "a server application" be?

>  - People might balk add installing all of the appstream-data package on
>    a server and then ignoring all of it except the five server apps we
>    actually have.  Can this be split easily?  Fedora could probably have
>    a different appstream-data-server package for the Server variant...

Sure, that's just a packaging issue. The XML files are all loaded and
merged at runtime anyway.

>  - We would have to consume the metainfo stuff in Cockpit, which likes
>    small servings of JSON.  How would we get a list of
>    type="server-application" components from the available appstream
>    cache?

That's something that I could easily add to appstream-glib if
required. What did you have in mind?

> Maybe PackageKit?

Not this :)

>  Maybe mandate YAML and just consume that?

YAML is only allowed for DEP-11 repos really (so just Debian in
practice) -- I'd really advise against using anything else other than
the XML spec in practice as the YAML is really an output-only format
in my head, although ximion might disagree.

>  - In this modern world, we will have to have a container story.  If
>    AppStream is the way to go, how do you feel about getting containers
>    in it as well?

I guess this makes sense, but we do have to be careful with feature
creep. AppStream does make sense as a generic "application"
description format, but we have to be careful not to be jack of all
trades.

> I know Flatpak uses AppStream, and I'll make sure
>    that Server Applications via Flatpak will totally be possible, but
>    maybe we also need to include Docker, System Containers, etc to the
>    party.  Has anyone thought about this already?

I think you're the first one the bring it up. I certainly think adding
better metadata to containers is hugely required.

Richard