Python package policies
Python packages in Alpine Linux should follow a general set of standards for their APKBUILDs.
 Pending consensus on this approach, some discussion is taking place on the talk page |
Guidelines
- Prefix Python 3 libraries with py3-, and Python 2 libraries with py2-. 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 "py-")
- Set _pyname 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
Python 3 only
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-$pkgver
build() {
python3 setup.py build
}
check() {
python3 setup.py test
}
package() {
python3 setup.py install --prefix=/usr --root="$pkgdir"
}
Python 2 & 3
Specify all of the runtime dependencies for both Python 2 & 3 in the makedepends.
# Maintainer: Joe Bloe <joe@example.org>
pkgname=py-alpine-name
_pyname=pypi-name
pkgver=1.2.3
pkgrel=0
pkgdesc="Example Python package"
url=https://example.org
arch=noarch
license=MIT
_py2_deps="..."
_py3_deps="..."
subpackages="py2-${pkgname#py-}:_py2 py3-${pkgname#py-}:_py3"
makedepends="py2-setuptools py3-setuptools $_py2_deps $_py3_deps"
_pypiprefix="${_pyname%${_pyname#?}}"
source="https://files.pythonhosted.org/packages/source/$_pypiprefix/$_pyname/$_pyname-$pkgver.tar.gz"
builddir=$srcdir/$_pyname-$pkgver
prepare() {
default_prepare
cp -r "$builddir" "$builddir"-py2
}
build() {
cd "$builddir"
python3 setup.py build
cd "$builddir"-py2
python2 setup.py build
}
check() {
cd "$builddir"
python3 setup.py test
cd "$builddir"-py2
python2 setup.py test
}
package() {
mkdir -p "$pkgdir"
}
_py2() {
depends="$_py2_deps"
cd "$builddir"-py2
_py python2
}
_py3() {
depends="$_py3_deps"
cd "$builddir"
_py python3
}
_py() {
_python="$1"
pkgdesc="$pkgdesc (for $_python)"
depends="$depends $_python"
install_if="$pkgname=$pkgver-r$pkgrel $_python"
$_python setup.py install --prefix=/usr --root="$subpkgdir"
}
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.
You need to use the 'tox' utility to run tests
tox (knows as py3-tox on Alpine Linux) downloads all dependencies into a virtual environment by default, which bypasses the system tooling, making testing somewhat less useful.
Remember to 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.
Different dependencies between py2 and py3 versions
Add depends="..." to the respective _py2 or _py3 subpackage functions.
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.
Python 2 deprecation
Pending consensus on this approach |
The general approach to Python 2 deprecation and removal requires three broad steps:
- Do not add new python 2 packages to aports, effective immediately.
- In the course of the aports normalization project, drop Python 2 support if it's easy or triage it and make a note for later if not.
- Making judgement calls for difficult packages on a case-by-case basis, based on the upstream's progress/amicability towards a Python 3 port. Upstreams which are unwilling to port to Python 3 should be removed from aports.
TODO: Prepare some discussion place, git repos, scripts, etc, to organize this work.