Python package policies: Difference between revisions

Latest revision as of 13:18, 26 February 2024

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

# 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.

@@ Line 1: / Line 1: @@
 Python packages in Alpine Linux should follow a general set of standards for their APKBUILDs.
-{{Draft|Pending consensus on this approach}}
+{{Draft|Pending consensus on this approach, some discussion is taking place on the [[Talk:Python_package_policies|talk page]]}}
+== Guidelines ==
+* Prefix Python 3 libraries with <code>py3-</code>. Do not prefix programs (distinct from libraries) at all.
 == General Template ==
-This APKBUILD template includes a split py2-/py3- package and a py- metapackage, and downloads the source package from PyPI. Be sure to make the following changes:
+Be sure to make the following changes:
 * Update maintainer to yourself
-* Set the pkgname to the Alpine package name (prefixed with "py-")
+* Set the pkgname to the Alpine package name (prefixed with "py3-")
-* Set _pkgname to the name of the package on PyPI
+* Set _pyname (see [[Talk:Python_package_policies|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 ===
 <pre># Maintainer: Joe Bloe <joe@example.org>
-pkgname=py-alpine-name
+pkgname=py3-alpine-name
-_pkgname=pypi-name
+_pyname=pypi-name
 pkgver=1.2.3
 pkgrel=0
 pkgdesc="Example Python package"
-url=http://example.org/
+url="https://example.org"
-arch=noarch
+arch="noarch"
-license=MIT
+license="MIT"
-subpackages="py2-${pkgname#py-}:_py2 py3-${pkgname#py-}:_py3"
+depends="python3"
-makedepends="py-setuptools"
+makedepends="py3-setuptools"
-source="https://files.pythonhosted.org/packages/source/${_pkgname:0:1}/$_pkgname/$_pkgname-$pkgver.tar.gz"
+_pypiprefix="${_pyname%${_pyname#?}}"
-builddir=$srcdir/$_pkgname-$pkgver
+source="https://files.pythonhosted.org/packages/source/$_pypiprefix/$_pyname/$_pyname-$pkgver.tar.gz"
+builddir="$srcdir/$_pyname-$pkgver"
-prepare() {
-	cp -r "$builddir" "$builddir"-py3
-}
 build() {
-	cd "$builddir"
-	python2 setup.py build
-	cd "$builddir"-py3
 	python3 setup.py build
 }
 check() {
-	cd "$builddir"
-	python2 setup.py test
-	cd "$builddir"-py3
 	python3 setup.py test
 }
 package() {
-	mkdir -p "$pkgdir"
+	python3 setup.py install --root="$pkgdir" --skip-build
-}
-_py2() {
-	cd "$builddir"
-	_py python2
-}
-_py3() {
-	cd "$builddir"-py3
-	_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"
 }</pre>
@@ Line 82: / Line 61: @@
 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.
-=== Different dependencies between py2 and py3 versions ===
+=== Upstream uses 'tox' to run tests ===
-Add depends="..." to the respective _py2 or _py3 subpackage functions.
+tox (packaged as {{Pkg|py3-tox}}) downloads all dependencies into a virtual environment. This bypasses the system packages negating a lot of the value in these tests.
-=== No python2 support ===
+You can use <code>--sitepackages</code> on your invocation of tox in the check() phase so it uses the system packages instead of downloading ones into a virtual environment.
-In this case, rename the package to "py3-example" and remove the "py-" metapackage and "py2-" subpackage. Merge the _py(), _py3,() and package() functions. Remove the prepare() function and drop the -py3 suffix from the builddir. An updated py3-only template is provided here:
+=== setup.py does not exist ===
-<pre># Maintainer: Joe Bloe <joe@example.org>
+In case a package uses a <code>pyproject.toml</code> instead of <code>setup.py</code>, you can use <code>py3-gpep517</code> and <code>py3-installer</code>. See {{Pkg|py3-rich}} for an example. Also note how to run tests against the built package in that example.
-pkgname=py-alpine-name
-_pkgname=pypi-name
-pkgver=1.2.3
-pkgrel=0
-pkgdesc="Example Python package"
-url=http://example.org/
-arch=noarch
-license=MIT
-depends="python3"
-makedepends="py-setuptools"
-source="https://files.pythonhosted.org/packages/source/${_pkgname:0:1}/$_pkgname/$_pkgname-$pkgver.tar.gz"
-builddir=$srcdir/$_pkgname-$pkgver
-build() {
+Many projects require either <code>py3-poetry-core</code>/<code>py3-flit-core</code> or just <code>py3-wheel</code>/<code>py3-setuptools</code> in makedepends alongside <code>py3-gpep517</code> to build successfully (check the <code>build-backend</code> in <code>pyproject.toml</code> to confirm the exact requirements).
-	cd "$builddir"
-	python3 setup.py build
-}
-check() {
-	cd "$builddir"
-	python3 setup.py test
-}
-package() {
-	python3 setup.py install --prefix=/usr --root="$pkgdir"
-}</pre>
-== Future work ==
+== Alpine+Python projects ==
 === aports normalization project ===
-Many Python packages in aports (if not most) do not follow these guidelines. TODO: figure out an approach and obtain consensus.
+Many Python packages in aports (if not most) do not follow these guidelines.
-=== Python 2 deprecation ===
+TODO: obtain consensus and organize this work.
-Python 2 is EoL in less than a year. Let's get rid of it. TODO: figure out an approach and obtain consensus.
+[[category: python]]