It's normal to extend python with C/C++. I have the need to extend with C#.

It works well to call C# libraries with the pythonnet package.

What I'm struggling with now is to create a python package that contains the C# binaries. Specifically it's setuptools that I'm unsure about.

I'm used to building my packages with:

python setup.py bdist_wheel

I have created a "command" in setup.py that can publish the C# binaries. It can be invoked with

python setup.py publish_dotnet

But how do I combine them? I could do:

python setup.py publish_dotnet
python setup.py bdist_wheel

I.e. running two commands and having bdist_wheel assume the publish_dotnet command has been run. But I'm hoping there is a way to boil it down to running one command that both builds the dotnet code and package it into a wheel.

For reference, here's a setup.py that adds arbitrary files to the wheel:

from setuptools import setup, find_namespace_packages
setup(
    packages=find_namespace_packages(where="src"),
    package_dir={"": "src"},
    package_data={
        "mypkg1.data": ["*.*"],
    }
)

Here's the setup.py that builds the dotnet code:

import os
import shutil
import distutils
from setuptools import Command, find_packages, setup
from setuptools.command.build import build


class publish_dotnet(Command):
    user_options = [
        ("dotnet-config=", None, "dotnet build configuration"),
        (
            "inplace",
            "i",
            "ignore build-lib and put compiled extensions into the source " + "directory alongside your pure Python modules",
        ),
    ]

    def initialize_options(self):
        self.announce("publish_dotnet.initialize_options", level=distutils.log.INFO)
        self.dotnet_config = None
        self.build_lib = None
        self.inplace = False

    def finalize_options(self):
        self.announce("publish_dotnet.finalize_options", level=distutils.log.INFO)
        if self.dotnet_config is None:
            self.dotnet_config = "release"

        build = self.distribution.get_command_obj("build")
        build.ensure_finalized()
        if self.inplace:
            self.build_lib = "."
        else:
            self.build_lib = build.build_lib

    def run(self):
        dotnet_publish_dir = "dotnet_published_binaries"

        self.announce("deleting old artifacts...", level=distutils.log.INFO)

        if os.path.isdir(dotnet_publish_dir):
            shutil.rmtree(dotnet_publish_dir)

        self.announce("publishing...", level=distutils.log.INFO)
        cmd = ["dotnet", "publish", "-o", dotnet_publish_dir, r"src\csharp\ClassLibrary1\ClassLibrary1.csproj"]
        self.spawn(cmd)


setup(
    cmdclass={"publish_dotnet": publish_dotnet},
)