Azure packaging

This article describes the recommendations for defining namespace packaging to release a package inside the azure namespace. Being inside the azure namespace means that a service myservice can be imported using:

import azure.myservice

Namespace packaging is complicated in Python, here's a few reading if you still doubt it:

Note: While this article provides an example using setup.py, this can also be achieved with setup.cfg or other methods, as long as the constraints on the final wheels/sdist are met.

This page has been updated to be Python 3 only packages as we do not recommend supporting Python 2 after January 1st 2022. If you still want to support Python 2 for some reasons, there is a section at the bottom with some details (or you have the Github history, to read the page as it was on November 1st 2021).

What are the constraints?

We want to build sdist and wheels in order to follow the following constraints:

Solution should work with recent versions of pip and setuptools (not the very latest only, but not archaeology either)
Wheels must work with Python 3.8+
mixed dev installation and PyPI installation should be explicitly addressed

What do I do in my files to achieve that

The minimal files to have:

azure/__init__.py
MANIFEST.in
setup.py

The file "azure/__init__.py" must contain exactly this:

__path__ = __import__('pkgutil').extend_path(__path__, __name__)

Your MANIFEST.in must include the following line include azure/__init__.py.

Example:

include *.md
include LICENSE
include azure/__init__.py
recursive-include tests *.py
recursive-include samples *.py *.md

In your setup.py:

The "packages" section MUST EXCLUDE the azure package. Example:

    packages=find_packages(exclude=[
        'tests',
        # Exclude packages that will be covered by PEP420 or nspkg
        'azure',
    ]),

Since the package is Python 3 only, you must notify it in the setup.py as well:

    python_requires=">=3.8",

Example of a full setup.py

#!/usr/bin/env python

#-------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License. See License.txt in the project root for
# license information.
#--------------------------------------------------------------------------

import re
import os.path
from io import open
from setuptools import find_packages, setup

# Change the PACKAGE_NAME only to change folder and different name
PACKAGE_NAME = "azure-keyvault"
PACKAGE_PPRINT_NAME = "KeyVault"

# a-b-c => a/b/c
package_folder_path = PACKAGE_NAME.replace('-', '/')
# a-b-c => a.b.c
namespace_name = PACKAGE_NAME.replace('-', '.')

# Version extraction inspired from 'requests'
with open(os.path.join(package_folder_path, 'version.py'), 'r') as fd:
    version = re.search(r'^VERSION\s*=\s*[\'"]([^\'"]*)[\'"]',
                        fd.read(), re.MULTILINE).group(1)

if not version:
    raise RuntimeError('Cannot find version information')

with open('README.rst', encoding='utf-8') as f:
    readme = f.read()
with open('HISTORY.rst', encoding='utf-8') as f:
    history = f.read()

setup(
    name=PACKAGE_NAME,
    version=version,
    description='Microsoft Azure {} Client Library for Python'.format(PACKAGE_PPRINT_NAME),
    long_description=readme + '\n\n' + history,
    license='MIT License',
    author='Microsoft Corporation',
    author_email='azpysdkhelp@microsoft.com',
    url='https://github.com/Azure/azure-sdk-for-python',
    classifiers=[
        'Development Status :: 4 - Beta',
        'Programming Language :: Python',
        'Programming Language :: Python :: 3 :: Only',
        'Programming Language :: Python :: 3',
        'Programming Language :: Python :: 3.8',
        'Programming Language :: Python :: 3.9',
        'Programming Language :: Python :: 3.10',
        'Programming Language :: Python :: 3.11',
        'Programming Language :: Python :: 3.12',
        'License :: OSI Approved :: MIT License',
    ],
    python_requires=">=3.8",
    zip_safe=False,
    packages=find_packages(exclude=[
        'tests',
        # Exclude packages that will be covered by PEP420 or nspkg
        'azure',
    ]),
    install_requires=[
        'msrest>=0.5.0',
        'msrestazure>=0.4.32,<2.0.0',
        'azure-common~=1.1',
    ],
)

This syntax works with setuptools >= 24.2.0 (July 2016) and pip >= 9.0 (Nov 2016), which is considered enough to support in 2021.

Since the package is Python 3 only, do NOT make this wheel universal. This usually means you should NOT have universal=1 in the setup.cfg. It may mean you can completely remove the file if universal was the only configuration option inside.

How can I check if my packages are built correctly?

wheel file must NOT contain a azure/__init__.py file (you can open it with a zip util to check)
wheel file name suffix is py3-none-any, and NOT py2.py3-none-any.
sdist must contain a azure/__init__.py file that declares azure as a namespace package using the pkgutil syntax

I already have a package that supports Python 2, can I get short version on how to udpate to Python 3 only?

Remove "universal" from setup.cfg, or completely remove the file if it was the only option
In setup.py:
- Remove extra_requires
- Add python_requires=">=3.8",
- Remove the Python 2 and 3.5/3.6 classifiers
- Add classifier Programming Language :: Python :: 3 :: Only
- Remove the "azure" check if applicable (see next note)

Note on checking old Azure packages

You may see code in setup.py looking like this:

# azure v0.x is not compatible with this package
# azure v0.x used to have a __version__ attribute (newer versions don't)
try:
    import azure

    try:
        VER = azure.__version__  # type: ignore
        raise Exception(
            "This package is incompatible with azure=={}. ".format(VER) + 'Uninstall it with "pip uninstall azure".'
        )
    except AttributeError:
        pass
except ImportError:
    pass

This was to prevent some difficult update scenario 6 years ago, and can be safely removed from your setup.py

Note on Python 2

The "extras_requires" section MUST include a conditional dependency on "azure-nspkg" for Python 2. Example:

    extras_require={
        ":python_version<'3.0'": ['azure-nspkg'],
    }

An additional verification is that wheels installs azure-nspkg ONLY on Python 2.