Developer guide

To get set up first clone the repo with the SSH link to eliminate password prompts on push.

git clone git@github.com:MetOffice/forest-lite.git

Then navigate inside the repo with cd forest-lite. At this point it may be convenient to set up a development environment but for simple edits, e.g. docstring changes, this step can be done later.

GitHub contributor flow

The inner workings of git are better documented elsewhere on the web. The advice here is to fork the repository, check out your fork and configure your remote and origin upstream locations to point to the correct places.

Conda environment

Follow steps to install miniconda on your machine. Then to create a dedicated environment for FOREST-Lite development create a new one with a supported Python version.

conda create -n forestlite python=3.8

Activate the environment and install the necessary package dependencies.

conda activate forestlite

Many of the packages are available in the conda-forge channel. To install from that channel use -c conda-forge. As we are setting up a development environment it is a good idea to also install test suite dependencies found in requirements-test.txt.

conda install -c conda-forge --file requirements.txt --file requirements-test.txt

At this point your new conda environment should have all of the necessary dependencies. The final step is to point Python at your edits.

python setup.py develop

If this is your first time running the above command all of the assets will be built.

Note

The webpack step takes a few minutes to complete with no output, this is normal behaviour.

Test suite

A good way to make sure your environment is set up and you are starting with the right stuff is to run both the server and client tests.

pytest --disable-warnings

To run the JavaScript tests navigate to forest_lite/client directory and run the following command.

npm run test

Jest test runner is configured to run with a file watcher which may be convenient when developing JS.

npm run watch

The development server can be launched to respond to live changes to the JS/CSS code via the webpack-dev-server lib.

npm start