Contributing to pylivy

Thanks for considering contributing to pylivy!

Asking questions and reporting issues

If you have any questions on using pylivy or would like to make a suggestion on improving pylivy, please open an issue on GitHub:

Submitting code changes

Before opening a PR, have a look at the information below on code formatting and tests. Tests will be run automatically on Travis and must pass before a PR can be merged.

Code formatting

Code must be formatted with Black (with a line length of 79, as configured in pyproject.toml), plus pass Flake8 linting and mypy static type checks.

It’s recommend that you configure your editor to autoformat your code with Black and to highlight any Flake8 or mypy errors. This will help you catch them early and avoid disappointment when the tests are run later!

Running tests

pylivy includes two types of code tests; unit tests and integration tests. The unit tests test individual classes of the code base, while the integration tests verify the behaviour of the library against an actual running Livy server.

To run the unit tests, which run quickly and do not require a Livy server to be running, first install tox (a Python testing tool) if you do not already have it:

pip install tox

then run:

tox -e py37

tox will build the project into a package, prepare a Python virtual environment with additional test dependencies, and execute the tests. You can also run tests against Python 3.6 by replacing py37 with py36 in the above command.

To run integration tests, you need to first start a Livy server to test against. For this purpose, I’ve prepared a Docker image that runs a basic Livy setup. To run it:

docker run --publish 8998:8998 acroz/livy

Then, in a separate shell, run the integration tests:

tox -e py37-integration

Again, you can replace py37 with py36 to change the Python version used.

Adding tests

Any new contributions to the library should include appropriate tests, possibly including unit tests, integration tests, or both. Please get in touch by opening an issue if you’d like to discuss what makes sense.

Both unit tests and integration tests are written with the pytest testing framework. If you’re not familiar with it, I suggest having a look at their extensive documentation and examples first.