Re: Location for user installed plugin libraries and icons

[Jon Gough <jonsgough@gmail.com>]

On 7/6/21 9:38 pm, jrb3-beckenbach.us wrote:
> Hi again, Jon!
>
> > On 6 Jun 2021, at 20:51, Jon Gough <jonsgough@gmail.com> wrote:
> > These suggest that a full cleanup could/should(?) be done including all user generated files.
> Not at all, because packages do not install any files to any user-$HOME.
> If the user generated (or triggered the generation of) any files, by definition the package-installer didn't create them,
> and by policy and following "the law of least surprise" the package-uninstaller shouldn't touch them.
>
> > If $HOME is not allowed to be touched by convention I was trying to ascertain where else they could be located that does not require root access to create, modify, delete so that the cleanup could be done.
> Two different approaches I've used for this situation over the decades have worked well for me.
> Not sure if either will be an improvement for you.
>
> 1/ Have the package-installer emplace a pseudo-group, with the plugin-manager set-group to that pseudo-group.
> Then, chgrp anything created for the user into his $HOME to that pseudo-group.  The user-invoked script to clean up $HOME
> then just has to look for file-system entries with that group.
>
> 2/ If you're absolutely dead-set on forcing clean-up of per-user files, *whether or not the user wants them cleaned up*,
> then just don't put anything in any $USER-home.  Problem solved.  Then, take your cue from {mail,news,uucp,cups,ftp,...}
> and keep all per-user files off in /var/spool/plug-package/ and/or a pseudo-user "home directory". On package-uninstall,
> make sure /var/spool/plug-package/ and pseudo-user "home directory" get cleared and removed.  (This is where you'd differ
> from {mail,news,uucp,cups,ftp,...} -- they won't clear and remove [or at least didn't the times I looked from ~1990 onward].)
That sounds like a solution putting the large binary read-only files in 
the /var/spool/plug-package directory. I presume, to avoid using root 
access all the time, that the directory would have to be rw by everyone 
who may be running the program, via a group, or just world. The worst 
that would happen is it gets deleted by mistake and the data would have 
to be downloaded again.
> Trade-off between 1/ and 2/ is "where do the files live" and "how much must the package harden itself from user interference".
>
> If you're dead-set on using space in each user's $HOME, option 1 it is.  Doing that means your package has explicitly given-over
> custody of those files to the user, since they're in the user-controlled space.  Your package has to have the user trigger clean-up,
I am not set on any particular location and have been put off $HOME by 
the clean up issue.
> using commands your package provides documented by your package.  Your plugin-manager also has to self-repair any changes
> made by the user in his file-space, since it's the user's file-space not yours and he'll do whatever he darn well pleases there.
>
> If it's just you want to make use of disk-space available on /home/ go ahead with option 2 and pseudo-user homed on /home/.
>
> Thanks!
>
> Joseph
> ——
> Joseph Beckenbach
> +1-678-602-3192 (EST/EDT)
Thanks for the suggestion, I will now investigate how to implement this.

Jon