Contributors Guide

We encourage outside contributors to perform changes on our codebase. Many such changes have been merged already. In order to make it easier to contribute, core developers of this project:

  • provide guidance (through the issue reporting system)

  • provide tool assisted code review (through the Pull Request system)

  • maintain a set of unit tests

  • maintain a set of integration tests (run with a production cloud)

  • maintain development automation tools using nox that can easily:

    • format the code using yapf

    • runs linters to find subtle/potential issues with maintainability

    • run the test suite on multiple Python versions using pytest

  • maintain Continuous Integration (by using GitHub Actions) that:

    • runs all sorts of linters

    • checks if the Python distribution can be built

    • runs all tests on a matrix of 6 versions of Python (including pypy) and 3 operating systems (Linux, Mac OS X and Windows)

    • checks if the documentation can be built properly

  • maintain other Continuous Integration tools (coverage tracker)

You’ll need to have nox installed:

  • pip install nox

With nox, you can run different sessions (default are lint and test):

  • format -> Format the code.

  • lint -> Run linters.

  • test (test-3.5, test-3.6, test-3.7, test-3.8, test-3.9) -> Run test suite.

  • cover -> Perform coverage analysis.

  • build -> Build the distribution.

  • deploy -> Deploy the distribution to the PyPi.

  • doc -> Build the documentation.

  • doc_cover -> Perform coverage analysis for the documentation.

For example:

$ nox -s format
nox > Running session format
nox > Creating virtual environment (virtualenv) using python3.9 in .nox/format

$ nox -s format
nox > Running session format
nox > Re-using existing virtual environment at .nox/format.

$ nox --no-venv -s format
nox > Running session format

Sessions test, unit, and integration can run on many Python versions, 3.5-3.9 by default.

Sessions other than test use the last given Python version, 3.9 by default.

You can change it:

export NOX_PYTHONS=3.6,3.7

With the above setting, session test will run on Python 3.6 and 3.7, and all other sessions on Python 3.7.

Given Python interpreters should be installed in the operating system or via pyenv.


To run all available linters:

$ nox -s lint


To run all tests on every available Python version:

$ nox -s test

To run all tests on a specific version:

$ nox -s test-3.9

To run just unit tests:

$ nox -s unit-3.9

To run just integration tests:

$ export B2_TEST_APPLICATION_KEY=your_app_key
$ export B2_TEST_APPLICATION_KEY_ID=your_app_key_id
$ nox -s integration-3.9


To build the documentation and watch for changes (including the source code):

$ nox -s doc

To just build the documentation:

$ nox --non-interactive -s doc