Re: [RFC PATCH v3 00/20] configure: create a python venv and ensure meson, sphinx

[Paolo Bonzini <pbonzini@redhat.com>]

On 4/26/23 10:21, Daniel P. Berrangé wrote:
>> So if you already have Sphinx, this should perform an upgrade to the
>> latest version?
>
> Essentially I meant 'force' to mean*never*  use the host python
> installation packages. Always install all the deps in the venv,
> even if they exist in the host with sufficient version met.

I think this is essentially --enable-isolated-venv.  I don't think there 
is a usecase for "let the venv use system packages, but override them 
with pip right away".

>>
>> --python=... # runtime used to create venv
>> --enable-pip-groups=testing,devel,avocado,meson,sphinx
>> --enable-pip=now  # install all python deps now
>> --enable-pip=on-demand  # install qemu.git/meson/sphinx, delay the rest
>> --enable-pip=no    # offline
>> --{enable,disable}-isolated-venv # let venv use system/distro if disable
> 
> This feels like a bit of overkill to me, and would create a hell
> of a lot of combinations to test if you expand the matrix of
> options.

Yeah, this is a bit overkill.  I think we can reduce it to three cases, 
corresponding to:

- --enable-pypi --enable-isolated-venv - use pip to install everything, 
including for options in "auto" state (e.g. would install sphinx without 
--enable-docs)

- --enable-pypi --disable-isolated-venv - use pip to install missing 
packages.  TBD whether to do so for options in "auto" state or only for 
"enabled" (i.e., TBD whether to install sphinx without --enable-docs).

- --disable-pypi (only meaningful for --disable-isolated-venv) - apart 
from vendored wheels, just use system site packages (same as QEMU <= 8.0)

I think we want to hash out this detail first, and thus we should leave 
online mode out of the non-RFC version.  It can be implemented together 
with isolated mode.

Paolo