add udunits xml to wheel

[bjlittle]

🚀 Pull Request

Description

This PR supports #186, by injecting the associated UDUNITS2 xml files into a wheel build of cf-units.

@ocefpaf To build in a quay.io/pypa/manylinux2014_x86_64 docker container, I had to do the following:

yum install -y udunits2-devel

export UDUNITS2_INCDIR="/usr/include/udunits2"
export UDUNITS2_LIBDIR="/usr/lib64"
export UDUNITS2_XML_PATH="/usr/share/udunits/udunits2.xml"

export PYBIN="/opt/python/cp38-cp38/bin/python"

$PYBIN -m pip install --upgrade pip wheel setuptools setuptools_scm build twine
$PYBIN -m build --sdist --wheel . --outdir /io/wheelhouse/

auditwheel repair /io/wheelhouse/*.whl

Note that, the UDUNITS2 XML files populate the etc/share directory only for a bdist_wheel and not a sdist.

When a wheel installed cf-units distro executes it auto-generates an ephemeral site.cfg pointing to the bundled XML files, and the rest of the machinery works as normal. The wheel should be consistent with regards to udunits2, as the wheel bundles the udunits2 dynamic library associated with the etc/share XML files

[codecov]

Codecov Report

Merging #191 (4abe85a) into main (2caad34) will increase coverage by 0.32%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #191      +/-   ##
==========================================
+ Coverage   90.63%   90.96%   +0.32%     
==========================================
  Files           7        6       -1     
  Lines         833      819      -14     
  Branches      105      103       -2     
==========================================
- Hits          755      745      -10     
+ Misses         64       62       -2     
+ Partials       14       12       -2     

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2caad34...4abe85a. Read the comment docs.

[bjlittle]

@ocefpaf Okay, so I've put this in draft for the moment, as I've discovered a way to avoid the use of the CFUNITS_WHEEL environment variable, which was a bit unpleasant to be honest, and I want entirely happy using that kind of approach.

I'll add my changes and test before taking this out of draft again 👍

[bjlittle]

@ocefpaf Okay, this is good to review now... fancy taking a peek?

[ocefpaf]

@ocefpaf Okay, this is good to review now... fancy taking a peek?

LGTM!

[bjlittle]

You've got merge rights @ocefpaf, right?

[ocefpaf]

You've got merge rights @ocefpaf, right?

I believe I do but merging is blocked. I guess we need 1 approving review.

[bjlittle]

@ocefpaf Awesome, nice one 🥇