postrm::downgrade?

[Niall Young <niall@chime.net.au>]

I'm aware you can downgrade packages with
    `apt-get --force-yes install package=version-revision`
but this doesn't seem to apply any postrm processing on the existing
version of the package being replaced.

How about a postrm::downgrade hook to reverse any changes made in the
new version's preinst::upgrade so that when the old version's preinst::upgrade
is applied you're not left with a potential mix of configuration?

I'm using a custom package pool for deploying software, but we need to
cleanly rollback if an upgrade doesn't go as expected.  Removing the
package entirely and reinstalling isn't an option, it needs to be done
seamlessly - i.e. reverse all changes made in the upgrade.  Is there
another way?

Niall Young                                    Chime Communications Pty Ltd
niall@chime.net.au                            Level 6, 263 Adelaide Terrace
Ph: (+61) 08 9213 1330 / 0408 192 797         Perth, Western Australia 6000

    "donate to our Charity of the month which is the Eating Disorders
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