cross platform pip-compile helper

platform_generate.py

import argparse
import platform
import sys
import subprocess
from pathlib import Path


def describe() -> dict:
    meta = {
        "python": "py" + ".".join(platform.python_version_tuple()[:2]),
        "platform": sys.platform,
        "machine": platform.machine(),
    }
    meta["file-prefix"] = "{python}-{platform}-{machine}-".format_map(meta)
    return meta


def generate_in_files(args) -> list[Path]:
    meta = describe()
    outpaths = []
    for fname in args.SRC_FILES:
        inpath = Path(fname)
        prefix = "{python}-{platform}-{machine}-".format_map(meta)
        outpath = inpath.parent / f"{prefix}{inpath.name}"
        outpaths.append(outpath)
        print(f"Generating {str(outpath)}")
        with open(inpath, "r") as f:
            data = f.read().format_map(meta)
            with open(outpath, "w") as of:
                of.write(data)
    return outpaths


def compile(paths: list[Path], pipcompile_args: list[str]):
    for fpath in paths:
        finalargs = ["pip-compile"] + pipcompile_args + [str(fpath)]
        print(f'{" ".join(finalargs)}')
        subprocess.check_call(finalargs)


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("SRC_FILES", nargs="+")
    parser.add_argument("--compile", action="store_true")
    args, unknown = parser.parse_known_args()

    outpaths = generate_in_files(args)
    if args.compile:
        compile(outpaths, unknown)


if __name__ == "__main__":
    main()

Kinda personal with some PyPA folks agreeing regarding the pinning being misunderstood. I don't think there's "official statements" in the project, short of "the ecosystem doesn't support cross-compilation so it's impossible, it might be once such support is in place". I know that Filipe Laíns works on a PEP to make CPython expose better details of the runtimes, that's one of the blockers and projects like Beeware/Briefcase are trying to look into the cross-compilation side of things.
Here are some notes from this year's packaging summit https://hackmd.io/@CAM-Gerlach/py-packaging-summit-2023.

So the current state hasn't changed, except maybe the new possibility to pin the build env deps that's not yet released.

As for the libraries pinning the runtime deps — that may work for somebody who doesn't expect their things to be used outside their own application, which might be a legit use-case for that specific person/project but wouldn't really be usable by the wider community. FWIW I'm happy with my per-env pinning setup, short of the non-reusable tox integration that I need to fix.