Contributing guide

Bug report

Any proven or suspected malfunction should be traced in a bug report, the latter being an issue in the Pandora2D github repository.

Don’t hesitate to do so: It is best to open a bug report and quickly resolve it than to let a problem remain in the project. Notifying the potential bugs is the first way for contributing to a software.

In the problem description, be as accurate as possible. Include:

  • The procedure used to initialize the environment

  • The incriminated command line or python function

  • The content of the input and output configuration files (content.json)

Contributing workflow

Any code modification requires a Merge Request. It is forbidden to push patches directly into master (this branch is protected).

It is recommended to open your Merge Request as soon as possible in order to inform the developers of your ongoing work. Please add WIP: before your Merge Request title if your work is in progress: This prevents an accidental merge and informs the other developers of the unfinished state of your work.

The Merge Request shall have a short description of the proposed changes. If it is relative to an issue, you can signal it by adding Closes xx where xx is the reference number of the issue.

Likewise, if you work on a branch (which is recommended), prefix the branch’s name by xx- in order to link it to the xx issue.

Pandora2D Classical workflow is :

  • (Not available yet) Check Licence and sign Contribution license agreement (Individual or Corporate)

  • Create an issue (or begin from an existing one)

  • Create a Merge Request from the issue: a MR is created accordingly with WIP:, Closes xx and associated xx-name-issue branch

  • Modify Pandora2D code from a local working directory or from the forge (less possibilities)

  • Git add, commit and push from local working clone directory or from the forge directly

  • Follow Conventional commits specifications for commit messages

  • Beware that pre-commit hooks can be installed for code analysis (see below pre-commit validation).

  • Launch the tests with pytest on your modifications (or don’t forget to add ones).

  • When finished, change your Merge Request name (erase WIP: in title ) and ask to review the code.

Contribution license agreement

Contribution license agreement

PANDORA2D requires that contributors sign out a Contributor LicenseAgreement. The purpose of this CLA is to ensure that the project has the necessary ownership or grants of rights over all contributions to allow them to distribute under the chosen license (Apache License Version 2.0)

To accept your contribution, we need you to complete, sign and email to cars@cnes.fr an Individual Contributor LicensingAgreement (ICLA) form and a Corporate Contributor Licensing Agreement (CCLA) form if you are contributing on behalf of your company or another entity which retains copyright for your contribution.

The copyright owner (or owner’s agent) must be mentioned in headers of all modified source files and also added to the NOTICE file.

Coding guide

Here are some rules to apply when developing a new functionality:

  • Include a comments ratio high enough and use explicit variables names. A comment by code block of several lines is necessary to explain a new functionality.

  • The usage of the print() function is forbidden: use the logging python standard module instead.

  • Each new functionality shall have a corresponding test in its module’s test file. This test shall, if possible, check the function’s outputs and the corresponding degraded cases.

  • All functions shall be documented (object, parameters, return values).

  • Factorize the code as much as possible. The command line tools shall only include the main workflow and rely on the pandora2d python modules.

  • If major modifications of the user interface or of the tool’s behaviour are done, update the user documentation (and the notebooks if necessary).

  • Do not add new dependencies unless it is absolutely necessary, and only if it has a permissive license.

  • Use the type hints provided by the typing python module.

  • Don’t use sys.exit but raise an exception instead. Exceptions can be catch when Pandora2d is used as a library. sys.exit doesn’t.

  • Correct project pylint errors (see below)

Pre-commit validation

Pre-commit hooks (black, pylint, mypy, sphinx-checking, nbstripout) for code analysis can be installed:

pre-commit install

This command installs the pre-commit hooks in .git/hooks/pre-commit from .pre-commit-config.yaml file configuration.

It is possible to test pre-commit before commiting:

pre-commit run --all-files                # Run all hooks on all files
pre-commit run --files pandora2d/__init__.py   # Run all hooks on one file
pre-commit run pylint                     # Run only pylint hook

It is possible to run only pylint tool to check code modifications:

cd PANDORA2D_HOME
pylint *.py pandora2d/*.py tests/*.py        # Run all pylint tests
pylint --list-msgs                      # Get pylint detailed errors informations

Pylint messages can be avoided (in particular cases !) adding “#pylint: disable=error-message-name” in the file or line. Look at examples in code.