Contributing to Eland#

Eland is an open source project and we love to receive contributions from our community — you! There are many ways to contribute, from writing tutorials or blog posts, improving the documentation, submitting bug reports and feature requests or writing code which can be incorporated into eland itself.

Bug reports#

If you think you have found a bug in eland, first make sure that you are testing against the latest version of eland - your issue may already have been fixed. If not, search our issues list on GitHub in case a similar issue has already been opened.

It is very helpful if you can prepare a reproduction of the bug. In other words, provide a small test case which we can run to confirm your bug. It makes it easier to find the problem and to fix it. Test cases should be provided as python scripts, ideally with some details of your Elasticsearch environment and index mappings, and (where appropriate) a pandas example.

Provide as much information as you can. You may think that the problem lies with your query, when actually it depends on how your data is indexed. The easier it is for us to recreate your problem, the faster it is likely to be fixed.

Feature requests#

If you find yourself wishing for a feature that doesn’t exist in eland, you are probably not alone. There are bound to be others out there with similar needs. Many of the features that eland has today have been added because our users saw the need. Open an issue on our issues list on GitHub which describes the feature you would like to see, why you need it, and how it should work.

Contributing code and documentation changes#

If you have a bugfix or new feature that you would like to contribute to eland, please find or open an issue about it first. Talk about what you would like to do. It may be that somebody is already working on it, or that there are particular issues that you should know about before implementing the change.

We enjoy working with contributors to get their code accepted. There are many approaches to fixing a problem and it is important to find the best approach before writing too much code.

Note that it is unlikely the project will merge refactors for the sake of refactoring. These types of pull requests have a high cost to maintainers in reviewing and testing with little to no tangible benefit. This especially includes changes generated by tools.

The process for contributing to any of the Elastic repositories is similar. Details for individual projects can be found below.

Fork and clone the repository#

You will need to fork the main eland code or documentation repository and clone it to your local machine. See Github fork a repo page - for help.

Further instructions for specific projects are given below.

Submitting your changes#

Once your changes and tests are ready to submit for review:

  1. Run the linter and test suite to ensure your changes do not break the existing code: (TODO Add link to the testing document)

    # Run Auto-format, lint, mypy type checker for your changes
    $ nox -s format
    # Run the test suite
    $ pytest --doctest-modules eland/ tests/
    $ pytest --nbval tests/notebook/
  2. Sign the Contributor License Agreement

    Please make sure you have signed our Contributor License Agreement. We are not asking you to assign copyright to us, but to give us the right to distribute your code without restriction. We ask this of all contributors in order to assure our users of the origin and continuing existence of the code. You only need to sign the CLA once.

  3. Rebase your changes

    Update your local repository with the most recent code from the main eland repository, and rebase your branch on top of the latest main branch. We prefer your initial changes to be squashed into a single commit. Later, if we ask you to make changes, add them as separate commits. This makes them easier to review. As a final step before merging we will either ask you to squash all commits yourself or we’ll do it for you.

  4. Submit a pull request

    Push your local changes to your forked copy of the repository and submit a pull request. In the pull request, choose a title which sums up the changes that you have made, and in the body provide more details about what your changes do. Also mention the number of the issue where discussion has taken place, eg “Closes #123”.

Then sit back and wait. There will probably be discussion about the pull request and, if any changes are needed, we would love to work with you to get your pull request merged into eland.

Please adhere to the general guideline that you should never force push to a publicly shared branch. Once you have opened your pull request, you should consider your branch publicly shared. Instead of force pushing you can just add incremental commits; this is generally easier on your reviewers. If you need to pick up changes from main, you can merge main into your branch. A reviewer might ask you to rebase a long-running pull request in which case force pushing is okay for that request. Note that squashing at the end of the review process should also not be done, that can be done when the pull request is integrated via GitHub.

Contributing to the eland codebase#


We internally develop using the PyCharm IDE. For PyCharm, we are currently using a minimum version of PyCharm 2019.2.4.

Configuring PyCharm And Running Tests#

(All commands should be run from module root)

  • Create a new project via 'Check out from Version

    Control'->'Git' on the "Welcome to PyCharm" page <or other>

  • Enter the URL to your fork of eland


  • Click 'Yes' for 'Checkout from Version Control'

  • Configure PyCharm environment:

    In 'Preferences' configure a 'Project: eland'->'Project Interpreter'. Generally, we recommend creating a virtual environment. (TODO link to installing for python version support)

  • In 'Preferences' set 'Tools'->'Python Integrated

    Tools'->'Default test runner' to pytest

  • In 'Preferences' set 'Tools'->'Python Integrated

    Tools'->'Docstring format' to numpy

  • Install development requirements. Open terminal in virtual environment and run
    pip install -r requirements-dev.txt
  • Setup Elasticsearch instance with docker
    ELASTICSEARCH_VERSION=elasticsearch:7.x-SNAPSHOT .ci/`
  • Check http://localhost:9200 to verify if ElasticSearch Instance is running.

  • Install local eland module <required to execute notebook tests>
    python install
  • To setup test environment -note this modifies Elasticsearch indices run
    python -m tests.setup_tests
  • To validate installation, open python console and run
    import eland as ed
    ed_df = ed.DataFrame('localhost', 'flights')
  • To run the automatic formatter and check for lint issues
    run `nox -s format`
  • To test specific versions of Python run
    nox -s test-3.8


  • Install pandoc on your system -
    # For Ubuntu or Debian
    sudo apt-get install -y pandoc
  • Install documentation requirements. Open terminal in virtual environment and run
    pip install -r docs/requirements-docs.txt
  • To verify/generate documentation run
    nox -s docs