Since we are python3 only for openstack we create a single python3
virtualenv to install all the packages into. This gives us the benefits
of installing into a virtualenv while still ensuring coinstallability.
This is a major change and will likely break many things.
There are several reasons for this. The change that started this effort
was pip stopped uninstalling packages which used distutils to generate
their package installation. Many distro packages do this which meant
that pip installed packages and distro packages could not coexist in the
global install space. More recently git has made pip installing repos as
root more difficult due to file ownership concerns.
Currently the switch to the global venv is optional, but if we go down
this path we should very quickly remove the old global installation
method as it has only caused us problems.
Major hurdles we have to get over are convincing rootwrap to trust
binaries in the virtualenvs (so you'll notice we update rootwrap
configs).
Some distros still have issues, keep them using the old setup for now.
Depends-On: https://review.opendev.org/c/openstack/grenade/+/880266
Co-Authored-By: Dr. Jens Harbott <frickler@offenerstapel.de>
Change-Id: If9bc7ba45522189d03f19b86cb681bb150ee2f25
a40f9cb91f