Zig Python Sdist

this is a toolset to build python source distributions for pypi directly using zig build. It's inspired by Loris Cro's talk Deinventing the Wheel.

It allows to add a python distribution to zig packages without dealing with python package metadata the traditional way.

You find a full usage example in the example/ directory.

build.zig api

to generate a python sdist archive, add the zig package to the build.zig.zon file of your existing zig >= 0.16.0 project by running:

zig fetch --save git+https://codeberg.org/dasimmet/zig-python-sdist

then, import the dependency and create a source distribution. You will have to specify all files or directories (subdirectories are not added recursively) necessary to build the extension to add to the sdist archive. the zig-python-sdist dependency is added automatically for you as well as a --fork command line argument to zig build at wheel build time.

constzig_python_sdist=@import("zig_python_sdist");pubfnbuild(b:*std.Build)void{constbuild_ext_step=b.step("bdist-wheel","build the extension module");{// generate a module from cpython headersconstcpython=zig_python_sdist.createCPythonModule(b,.{.target=target,.version=zon.version,});// create a shared library, linked against cpythonconstsdist_dummy=b.addLibrary(.{.name="sdist_dummy",.linkage=.dynamic,.root_module=b.createModule(.{.root_source_file=b.path("sdist_dummy.zig"),.target=target,.optimize=optimize,.imports=&.{.{.name="cpython",.module=cpython},},}),});// install the extension on the "bdist-wheel" top level stepconstsdist_dummy_install=zig_python_sdist.installExtLib(b,sdist_dummy);build_ext_step.dependOn(&sdist_dummy_install.step);}constsdist=zig_python_sdist.createSdistStep(b,.{.name="python-package-name",.version=@import("build.zig.zon).version,.description=b.path("README.md"),.build=.{// the source distribution will build the "bdist-wheel" step on wheel build.args=&.{b.fmt("-Doptimize={s}",.{@tagName(optimize)}),build_ext_step.name,},},// add all files and directories necessary to build to the source distribution.files=&.{.{.src=b.path("build.zig.zon"),.dest="build.zig.zon"},.{.src=b.path("build.zig"),.dest="build.zig"},.{.src=b.path("README.md"),.dest="README.md"},.{.src=b.path("LICENSE"),.dest="LICENSE"},},.directories=&.{.{.src=b.path("src"),.dest="src"},},// tip: when adding dependency directories, pass a `--fork=<path inside sdist>` to// the build arguments.});// the install step only builds the source distributionconstsdist_install=sdist.install();b.getInstallStep().dependOn(&sdist_install.step);}

cpython zig module

the generated cpython module provides a c member holding the translated cpython headers as well as some utility functions to:

• addVersion adds __version__ and __version_str__ symbols to your module.
• addZigBuiltin adds a __zig_builtin__ symbol to your module populated by zig's build information.
• wrapMain wraps a Zig "JuicyMain" function (fn (std.process.Init) !void) to be used as an entrypoint for your python module, by populating the std.process.init from python's builtin os and sys modules.

take a look at example/sdist_dummy.zig

Testing the distribution installation

to test the built source distribution, you can create a VenvInstallTest step that will:

• create a python virtual environment
• compile and install your package
• run python unittest files against the installed package
• run entrypoints from the installed package to test them

References

• Deinventing the Wheel - Loris Cro
• https://pypi.org/project/setuptools-zig/
• https://pypi.org/project/zig-zon
• https://codeberg.org/dasimmet/python-zig-zon