Python package policies

From Alpine Linux
Revision as of 13:17, 26 February 2024 by WhyNotHugo (talk | contribs) (→‎Guidelines: Formatting)

Python packages in Alpine Linux should follow a general set of standards for their APKBUILDs.

This material is work-in-progress ...

Pending consensus on this approach, some discussion is taking place on the talk page
(Last edited by WhyNotHugo on 26 Feb 2024.)

Guidelines

  • Prefix Python 3 libraries with py3-. Do not prefix programs (distinct from libraries) at all.

General Template

Be sure to make the following changes:

  • Update maintainer to yourself
  • Set the pkgname to the Alpine package name (prefixed with "py3-")
  • Set _pyname (see talk page) to the name of the package on PyPI
  • Update the version number, pkgdesc, url, and license
  • Build it and address any issues that come up
  • Read the build output and be vigilant for issues listed in the following sections - the build may complete successfully even though these issues are present

Package template

Note that if you are removing python2 support from a package which previously had it, you should add

replaces="py2-example"

as well. If the old package was a split package, also add

replaces="py-example"
provides="py-example=$pkgver-r$pkgrel"

.

# Maintainer: Joe Bloe <joe@example.org>
pkgname=py3-alpine-name
_pyname=pypi-name
pkgver=1.2.3
pkgrel=0
pkgdesc="Example Python package"
url="https://example.org"
arch="noarch"
license="MIT"
depends="python3"
makedepends="py3-setuptools"
_pypiprefix="${_pyname%${_pyname#?}}"
source="https://files.pythonhosted.org/packages/source/$_pypiprefix/$_pyname/$_pyname-$pkgver.tar.gz"
builddir="$srcdir/$_pyname-$pkgver"

build() {
	python3 setup.py build
}

check() {
	python3 setup.py test
}

package() {
	python3 setup.py install --root="$pkgdir" --skip-build
}

Common issues

No source package available (only the wheel is on PyPI)

Seek out the upstream source (e.g. GitHub) and swap out the URL.

No tests in PyPI package "(0 tests run)"

Seek out the upstream source (e.g. GitHub) and swap out the URL.

setup.py test downloads a lot of dependencies

Watch out for this and be sure to add any of these packages to checkdepends so that setuptools isn't downloading and testing against packages/versions which aren't in aports.

Upstream uses 'tox' to run tests

tox (packaged as py3-tox) downloads all dependencies into a virtual environment. This bypasses the system packages negating a lot of the value in these tests.

You can use --sitepackages on your invocation of tox in the check() phase so it uses the system packages instead of downloading ones into a virtual environment.

setup.py does not exist

In case a package uses a pyproject.toml instead of setup.py, you can use py3-gpep517 and py3-installer. See py3-rich for an example. Also note how to run tests against the built package in that example.

Many projects require either py3-poetry-core/py3-flit-core or just py3-wheel/py3-setuptools in makedepends alongside py3-gpep517 to build successfully (check the build-backend in pyproject.toml to confirm the exact requirements).

Alpine+Python projects

aports normalization project

Many Python packages in aports (if not most) do not follow these guidelines.

TODO: obtain consensus and organize this work.