Re: [PATCH] Python: discourage direct setup.py install

[John Snow]

On Wed, Feb 9, 2022 at 7:51 AM Beraldo Leal <bleal@redhat.com> wrote:
>
> On Mon, Feb 07, 2022 at 04:30:39PM -0500, John Snow wrote:
> > When invoking setup.py directly, the default behavior for 'install' is
> > to run the bdist_egg installation hook, which is ... actually deprecated
> > by setuptools. It doesn't seem to work quite right anymore.
> >
> > By contrast, 'pip install' will invoke the bdist_wheel hook
> > instead. This leads to differences in behavior for the two approaches. I
> > advocate using pip in the documentation in this directory, but the
> > 'setup.py' which has been used for quite a long time in the Python world
> > may deceptively appear to work at first glance.
>
> +1 for that. Using setup.py directly is no longer a good practice. All
> direct invocations of setup.py are deprecated.
>
> > ---
> >  python/setup.py | 19 ++++++++++++++++++-
> >  1 file changed, 18 insertions(+), 1 deletion(-)
> >
> > diff --git a/python/setup.py b/python/setup.py
> > index 2014f81b75..c5bc45919a 100755
> > --- a/python/setup.py
> > +++ b/python/setup.py
> > @@ -5,9 +5,26 @@
> >  """
> >
> >  import setuptools
> > +from setuptools.command import bdist_egg
> > +import sys
> >  import pkg_resources
> >
> >
> > +class bdist_egg_guard(bdist_egg.bdist_egg):
> > +    """
> > +    Protect against bdist_egg from being executed
> > +
> > +    This prevents calling 'setup.py install' directly, as the 'install'
> > +    CLI option will invoke the deprecated bdist_egg hook. "pip install"
> > +    calls the more modern bdist_wheel hook, which is what we want.
> > +    """
> > +    def run(self):
> > +        sys.exit(
> > +            'Installation directly via setup.py is not supported.\n'
> > +            'Please use `pip install .` instead.'
> > +        )
> > +
> > +
> >  def main():
> >      """
> >      QEMU tooling installer
> > @@ -16,7 +33,7 @@ def main():
> >      # 
> > https://medium.com/@daveshawley/safely-using-setup-cfg-for-metadata-1babbe54c108
> >      pkg_resources.require('setuptools>=39.2')
> >
> > -    setuptools.setup()
> > +    setuptools.setup(cmdclass={'bdist_egg': bdist_egg_guard})
> >
> >
>
> Reviewed-by: Beraldo Leal <bleal@redhat.com>
>
> --
> Beraldo
>

Thanks, staging this one to my python branch.

--js