Bug#907313: Lack of guidelines on purging conffiles in stateless packages

[Russ Allbery <rra@debian.org>]

Gioele Barabucci <gioele@svario.it> writes:

> For instance, apache (the application) is configured by some stub conf
> in `/etc/apache` that loads *.conf files from directories such as
> `/etc/apache2/sites-enabled/`. The real files are usually in
> `/etc/apache2/sites-available/`.

> The purge process for the apache (the package) removes the configuration
> files it has installed and the symlinks it has created but leaves the
> configuration files written by the sysadmin alone.

Yeah, this is a very interesting example.  If the administrator puts a
bunch of local configuration in /etc/apache2/sites-available and related
directories, those are pretty clearly intended to be configuration files
of Apache, but should we delete everything in those directories on purge?
I can imagine someone being *quite* surprised by that.

Another thing that makes this less obvious is that this mechanism is
frequently used for cross-package cooperation.  In a sense, everything
under /etc/apache2 is a configuration file for Apache, but a bunch of
other packages do install files into that hierarchy (including things that
don't strongly depend on Apache), so running rm -rf in postrm purge isn't
necessarily correct.

-- 
Russ Allbery (rra@debian.org)               <http://www.eyrie.org/~eagle/>