Fix RPM System User Deletion on Upgrade

[pcting]

This is an extension to this commit to fix the RPM upgrade problem.

I've been having problems with my system user being deleted on an RPM upgrade. So I dug deeper and i found this problem:

$ rpm -qp --scripts  myrpm.noarch.rpm
... (stripped out unrelated stuff) ...
postuninstall scriptlet (using /bin/sh):
# Removing system user/group : XXX and XXX
echo "Try deleting system user and group [XXX:XXX]"
if getent passwd | grep -q "^XXX:"; 
then
    echo "Deleting system user: XXX"
    userdel XXX
fi
if getent group | grep -q "^XXX:" ;
then
    echo "Deleting system group: XXX"
    groupdel XXX
fi

So I copied the postuninstall into my project's /src/rpm/scriptlets/postun-rpm and the problem resolved itself.

It feels strange that there's multiple copies of the same script; I'm guessing some clean up will need to be done. Anyhow, here's a pull request that should fix the problem for the time being.

Thanks!

[lightbend-cla-validator]

Hi @pcting,

Thank you for your contribution! We really value the time you've taken to put this together.

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[muuki88]

Ah, I see. The main point for copying these files, was to keep the systemstart systems
separated. Uninstalling requires unregistering your application at some point. And before
creating a mix between shared and non-shared scripts, we separated them completely.

However IMHO we should at somepoint consolidate things. So we built up custom scripts from
common blocks. @kardapoltsev

[muuki88]

Ah, I see. Thanks for the fix.

The main goal at the beginning was to keep bootup-systems separated. You need
custom register/unregister methods in the lifecycle-scripts. So before creating a
mess we kept them separated.

However, now we gained a lot more insights, we should consolidate them in a way
that custom scripts are built from common blocks. @kardapoltsev what do you think?

[muuki88]

merged into v0.7.x