PyPack

What does it mean?

The name "PyPack" comes from the contraction of "Python" and "Package".

What is it for?

PyPack is a template for Python package repositories on GitLab.

Is it hard to use?

You need to be a bit familiar with python project packaging.

Background

Creating a package distribution for a Python project is a process that can already take some time. Putting it all together in a repository that allows full use of GitLab's CI/CD features can seem like a daunting extra step. The goal here is to simplify these processes by presenting a working example of a package distribution repository that uses CI/CD features.

Here are some references and recommended readings about the creation of Python package distributions and the use of CI/CD features:

• Tool recommendations
• Packaging Python Projects
• PyPi classifiers
• Git Basics - Tagging
• .gitlab-ci.yml keyword reference

Usage

The Python package used as an example here is called "Stemplate". The following explains how this package is automatically tested and deployed on PyPi thanks to the CI/CD features.

Deployment

To use this template follow these steps:

• Download or clone the PyPack project from its GitLab repository.

git clone git@gitlab.com:stemplate/pypack.git

• Replace all occurrences of "stemplate" with the name of your Python package. (Use your editor's search tool.)
• Adapt the pyproject.toml file, and add your potential dependencies. (Here NumPy is an example of a dependency.)
• Use template.md as a template for the new README.md.
• Install the Python virtual environment with the command source setup.sh.
• Incorporate/adapt your package source files in the src/ directory.
• Add the test functions for your package in the tests/run.py script.
• Remove the .git directory and initialize a new one:

git init --initial-branch=main
git add <your-files>
git commit -m "initial commit"
git tag -a v1.0.0rc1 -m "version 1.0.0rc1"

• Build and upload the package to Pypi:

python3 -m pip install --upgrade pip
python3 -m pip install --upgrade twine
python3 -m pip install --upgrade build
python3 -m build
python3 -m twine upload dist/*

• Create an empty repository on GitLab for your package distribution.
• Create an API token for the project on PyPi. (Use the url address of your GitLab repository to name the token in PyPi.)
• Add the PyPi Token variables on GitLab (Project > Settings > CI/CD > Variables):
  1. TWINE_USERNAME: __token__ (Add "Protect", "Mask", and "Expand" options)
  2. TWINE_PASSWORD: token value (Add "Protect", "Mask", and "Expand" options)
• Protect the v* wildcard tag (Project > Settings > Repository > Protected tags).
• Make sure that the main branch is protected and set "Allowed to push and merge" to "No one" (Project > Settings > Repository > Protected branch).
• Push:

git remote add origin git@gitlab.com:<user/project>.git
git push origin main --tags
git branch --set-upstream-to=origin/main main

Development

At this stage your project is deployed on both GitLab and PyPi, and the pipeline should have been launched on GitLab. The latter is configured in the .gitlab-ci.yml YAML file. The configuration proposed in this file allows to run the tests each time GitLab receives a push.

• Do not work on the main branch, create another one (like dev).
• Make some potential modifications so that the pipeline runs without errors.
• After merging your working branch into the main branch, if the pipeline passed, add a tag v1.0.0 "version 1.0.0" directly on GitLab. This will automatically deploy the new release on PyPi.
• Delete the working branch.

Repeat these steps (from creating a new branch) for each modification made to the project (without forgetting to adapt the version in the tag name).

Credits

• Dunstan Becht

License

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.