[Piuparts-devel] Bug#850917: Please export /var/lib/dpkg/alternatives content after installation

[Andreas Beckmann]

On 2017-01-22 14:43, Michael Stapelberg wrote:
> Thanks for the review! Answers inline:

I'm thinking about making this more generally useful.

For the piuparts command you want something like

  piuparts ... --copy-file-from-chroot <filename-inside-chroot>
<filename-outside-chroot>

I don't think exporting more than one file is feasible with a
master-slave setup.

Then you could implement *anything* via custom scripts inside the
chroot, e.g. exporting the alternatives in
pre_install_export_alternatives, post_install_export_alternatives and
build a final single tarball in post_purge_export_alternatives.
Report the md5sum of the export file from post_purge_export_alternatives
(just in case something gets mixed up later on).
If you need extra packages in the chroot for these scripts, use
--fake-essential-packages

These scripts would be given with an extra
  --scriptsdir /etc/piuparts/scripts-export-alternatives

The slave should send the aux file immediately before the corresponding
log file and after sending logs for a section delete all unknown aux
files. aux files without log file should be deleted, not sent to master.

master-bin/archive_old_logs should also handle old aux files.

piuparts-slave should only pass the --copy-file-from-chroot option (or
however it is named) if the section is set up for exporting some stuff
The filename-inside-chroot should come from the section config.
The filename-outside-chroot should be generated by piuparts-slave, in
the package_version.extension format, the extension being something
general like .blob, don't assume a special format like .tar.xz.
By default this new feature should be disabled.

For the final patch I would probably want to see it as a series of
commits e.g. master-slave protocol support, piuparts support, glueing it
together.

I expect this will be a project for buster, not stretch, I don't want to
hurry this into piuparts for stretch.


Andreas