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Features

PyScaffold comes with a lot of elaborated features and configuration defaults to make the most common tasks in developing, maintaining and distributing your own Python package as easy as possible.

Configuration, Packaging & Distribution

All configuration can be done in setup.cfg like changing the description, url, classifiers, installation requirements and so on as defined by setuptools. That means in most cases it is not necessary to tamper with setup.py. The syntax of setup.cfg is pretty much self-explanatory and well commented, check out this :ref:`example <configuration>` or setuptools' documentation.

In order to build a source, binary or wheel distribution, just run python setup.py sdist, python setup.py bdist or python setup.py bdist_wheel.

Uploading to PyPI

Of course uploading your package to the official Python package index PyPI for distribution also works out of the box. Just create a distribution as mentioned above and use twine to upload it to PyPI, e.g.:

pip install twine
twine upload dist/*

For this to work, you have to first register a PyPI account. If you just want to test, please be kind and use TestPyPI before uploading to PyPI.

Warning

Be aware that the usage of python setup.py upload for PyPI uploads also works but is nowadays strongly discouraged and even some of the new PyPI features won't work correctly if you don't use twine.

Namespace Packages

Optionally, namespace packages can be used, if you are planning to distribute a larger package as a collection of smaller ones. For example, use:

putup my_project --package my_package --namespace com.my_domain

to define my_package inside the namespace com.my_domain in java-style.

Package and Files Data

Additional data, e.g. images and text files, that reside within your package and are tracked by Git will automatically be included (include_package_data = True in setup.cfg). It is not necessary to have a MANIFEST.in file for this to work. Just make sure that all files are added to your repository. To read this data in your code, use:

from pkgutil import get_data
data = get_data('my_package', 'path/to/my/data.txt')

Starting from Python 3.7 an even better approach is using importlib.resources:

from importlib.resources import read_text, read_binary
data = read_text('my_package', 'path/to/my/data.txt')

The library importlib_resources provides a backport of this feature.

Complete Git Integration

Your project is already an initialised Git repository and setup.py uses the information of tags to infer the version of your project with the help of setuptools_scm. To use this feature you need to tag with the format MAJOR.MINOR[.PATCH] , e.g. 0.0.1 or 0.1. Run python setup.py --version to retrieve the current PEP440-compliant version. This version will be used when building a package and is also accessible through my_project.__version__.

Unleash the power of Git by using its pre-commit hooks. This feature is available through the --pre-commit flag. After your project's scaffold was generated, make sure pre-commit is installed, e.g. pip install pre-commit, then just run pre-commit install.

It goes unsaid that also a default .gitignore file is provided that is well adjusted for Python projects and the most common tools.

Sphinx Documentation

Build the documentation with python setup.py docs and run doctests with python setup.py doctest after you have Sphinx installed. Start editing the file docs/index.rst to extend the documentation. The documentation also works with Read the Docs.

The Numpy and Google style docstrings are activated by default. Just make sure Sphinx 1.3 or above is installed.

Dependency Management in a Breeze

PyScaffold out of the box allows developers to express abstract dependencies and take advantage of pip to manage installation. It also can be used together with a virtual environment to avoid dependency hell during both development and production stages.

In particular, PyPA's Pipenv can be integrated in any PyScaffold-generated project by following standard setuptools conventions. Keeping abstract requirements in setup.cfg and running pipenv install -e . is basically what you have to do (details in :ref:`Dependency Management <dependencies>`).

Warning

Experimental Feature - Pipenv support is experimental and might change in the future

Unittest & Coverage

Run python setup.py test to run all unittests defined in the subfolder tests with the help of py.test and pytest-runner. Some sane default flags for py.test are already defined in the [pytest] section of setup.cfg. The py.test plugin pytest-cov is used to automatically generate a coverage report. It is also possible to provide additional parameters and flags on the commandline, e.g., type:

python setup.py test --addopts -h

to show the help of py.test.

JUnit and Coverage HTML/XML

For usage with a continuous integration software JUnit and Coverage XML output can be activated in setup.cfg. Use the flag --travis to generate templates of the Travis configuration files .travis.yml and tests/travis_install.sh which even features the coverage and stats system Coveralls. In order to use the virtualenv management and test tool Tox the flag --tox can be specified. If you are using GitLab you can get a default .gitlab-ci.yml also running pytest-cov with the flag --gitlab.

Managing test environments with tox

Run tox to generate test virtual environments for various python environments defined in the generated :file:`tox.ini`. Testing and building sdists for python 2.7 and python 3.4 is just as simple with tox as:

tox -e py27,py34

Environments for tests with the the static code analyzers pyflakes and pep8 which are bundled in flake8 are included as well. Run it explicitly with:

tox -e flake8

With tox, you can use the --recreate flag to force tox to create new environments. By default, PyScaffold's tox configuration will execute tests for a variety of python versions. If an environment is not available on the system the tests are skipped gracefully. You can rely on the tox documentation for detailed configuration options.

Management of Requirements & Licenses

Installation requirements of your project can be defined inside setup.cfg, e.g. install_requires = numpy; scipy. To avoid package dependency problems it is common to not pin installation requirements to any specific version, although minimum versions, e.g. sphinx>=1.3, or maximum versions, e.g. pandas<0.12, are used sometimes.

More specific installation requirements should go into requirements.txt. This file can also be managed with the help of pip compile from pip-tools that basically pins packages to the current version, e.g. numpy==1.13.1. The packages defined in requirements.txt can be easily installed with:

pip install -r requirements.txt

All licenses from choosealicense.com can be easily selected with the help of the --license flag.

Extensions

PyScaffold comes with several extensions:

  • Create a Django project with the flag --django which is equivalent to django-admin.py startproject my_project enhanced by PyScaffold's features.
  • With the help of Cookiecutter it is possible to further customize your project setup with a template tailored for PyScaffold. Just use the flag --cookiecutter TEMPLATE to use a cookiecutter template which will be refined by PyScaffold afterwards.
  • ... and many more like --gitlab to create the necessary files for GitLab.

There is also documentation about :ref:`writing extensions <extensions>`.

Warning

Deprecation Notice - In the next major release both Cookiecutter and Django extensions will be extracted into independent packages. After PyScaffold v4.0, you will need to explicitly install pyscaffoldext-cookiecutter and pyscaffoldext-django in your system/virtualenv in order to be able to use them.

Easy Updating

Keep your project's scaffold up-to-date by applying putput --update my_project when a new version of PyScaffold was released. An update will only overwrite files that are not often altered by users like setup.py. To update all files use --update --force. An existing project that was not setup with PyScaffold can be converted with putup --force existing_project. The force option is completely safe to use since the git repository of the existing project is not touched! Also check out if :ref:`configuration options <configuration>` in setup.cfg have changed.

Updates from PyScaffold 2

Since the overall structure of a project set up with PyScaffold 2 differs quite much from a project generated with PyScaffold 3 it is not possible to just use the --update parameter. Still with some manual efforts an update from a scaffold generated with PyScaffold 2 to PyScaffold 3's scaffold is quite easy. Assume the name of our project is old_project with a package called old_package and no namespaces then just:

  1. make sure your worktree is not dirty, i.e. commit all your changes,
  2. run putup old_project --force --no-skeleton -p old_package to generate the new structure inplace and cd into your project,
  3. move with git mv old_package/* src/old_package/ --force your old package over to the new src directory,
  4. check git status and add untracked files from the new structure,
  5. use git difftool to check all overwritten files, especially setup.cfg, and transfer custom configurations from the old structure to the new,
  6. check if python setup.py test sdist works and commit your changes.

Adding features

With the help of an experimental updating functionality it is also possible to add additional features to your existing project scaffold. If a scaffold lacking .travis.yml was created with putup my_project it can later be added by issuing putup --update my_project --travis. For this to work, PyScaffold stores all options that were initially used to put up the scaffold under the [pyscaffold] section in setup.cfg. Be aware that right now PyScaffold provides no way to remove a feature which was once added.