Problem with ksycoca not being regenerated under flatpak

[Aleix Pol]

On Sun, Jun 20, 2021 at 11:29 AM Albert Astals Cid <aacid at kde.org> wrote:
>
> El diumenge, 13 de desembre de 2020, a les 22:15:26 (CEST), Albert Astals Cid va escriure:
> > El dissabte, 12 de desembre de 2020, a les 22:59:58 CET, David Faure va escriure:
> > > Time flies, sorry for the delay.
> > >
> > > On samedi 12 septembre 2020 19:44:45 CET Albert Astals Cid wrote:
> > > > flatpak mounts all files as if created on January 1st 1970.
> > >
> > > Isn't that a bug in itself? Why doesn't it preserve mtimes?
> >
> > I don't know, because reasons i guess, i never fully understood the answers i got on the flatpak mailing list
> >
> > https://lists.freedesktop.org/archives/flatpak/2020-October/002049.html
> >
> > https://lists.freedesktop.org/archives/flatpak/2020-November/002057.html
> >
> > >
> > > > This has the unfortunate effect that when we add new plugins to a flatpak
> > > > (i.e. we just added markdown preview support in kate), they are not seen
> > > > because ksycoca doesn't feel the need to regenerate itself (the sycoca file
> > > > for flatpak is written "outside" flatpak container and thus has a newer
> > > > date).
> > > >
> > > > I remember talking about this probably a year ago at least with Aleix, but i
> > > > guess we did not come up with any solution since it's still broken :D
> > > >
> > > > I don't know much about sycoca, but can we make it so the cache always get
> > > > regenerated on app launch when run under flatpak?
> > >
> > > Is there no way to manually "touch" a directory after adding new files?
> > >
> > > Otherwise, the hack you have in mind could be implemented as in the attached
> > > patch. Untested, except that it compiles.
> >
> > I'll test the patch at some point, thanks for caring :)
>
> So I did *not* test the patch, but I got someone else to test it
> https://github.com/flathub/org.kde.kdenlive/issues/118#issuecomment-864382857
>
> And it seems to solve the problem :)
>
> Big question left is, should we apply that patch you made directly in KService or do you prefer we apply it only when compiling the flatpak runtime?

I would much prefer if we didn't patch in the packaging. If there's
risk in having this outside of flatpak, I'd ifdef it.

Aleix