Cleaning of $XDG_CACHE_HOME and $XDG_CACHE_HOME/thumbnails

[Bastien Nocera]

On Wed, 2020-02-26 at 15:24 +0100, Benjamin Berg wrote:
> Hi,
> 
> On Wed, 2020-02-26 at 15:14 +0100, Bastien Nocera wrote:
> > Flatpak'ed applications also use a different cache directory, like:
> > $ export | grep CACHE
> > declare -x XDG_CACHE_HOME="/home/hadess/.var/app/<app-id>/cache"
> > 
> > I'd say that it might better left well alone, and have something
> > like
> > Baobab better signal what each directory is/which application it
> > belongs to, to clean it up.
> 
> This specification change would only affect the $XDG_CACHE_HOME as
> set
> at login time by pam_systemd (i.e. ~/.cache).
> 
> So in principle, Flatpak'ed applications are not affected at all.
> However, the logical extension of this proposal would be that
> appropriate configurations are shipped inside each Flatpak. Then we
> also have a cleanup mechanism there that does not depend on the
> application to be run regularly.
> 
> I had not thought about that yet. I could imagine Flatpak collecting
> the information and doing the simple re-write and dropping it into
> ~/.config/tmpfiles.d or $XDG_RUNTIME_DIR/tmpfiles.d at login time.
> And
> Flatpak itself could again ship a default to clean .var/app/*/cache
> by 
> default.

In this case, an opt-in would be less surprising than an opt-out.