jupyterlite-xeus-python

The xeus-python Python kernel for JupyterLite running in the browser.

Install

You can install the kernel with conda/mamba:

mamba install -c conda-forge jupyterlite-xeus-python

Or using pip:

pip install jupyterlite-xeus-python

Then build your JupyterLite site:

jupyter lite build

Pre-installed packages

xeus-python allows you to pre-install packages in the Python runtime. You can pre-install packages by adding an environment.yml file in the JupyterLite build directory, this file will be found automatically by xeus-python which will pre-build the environment when running jupyter lite build.

Furthermore, this automatically installs any labextension that it founds, for example installing ipyleaflet will make ipyleaflet work without the need to manually install the jupyter-leaflet labextension.

Say you want to install NumPy, Matplotlib and ipycanvas, it can be done by creating the environment.yml file with the following content:

name: xeus-python-kernel
channels:
  - https://repo.mamba.pm/emscripten-forge
  - conda-forge
dependencies:
  - numpy
  - matplotlib
  - ipycanvas

Then you only need to build JupyterLite:

jupyter lite build

You can also pick another name for that environment file (e.g. custom.yml), by doing so, you will need to specify that name to xeus-python:

jupyter lite build --XeusPythonEnv.environment_file=custom.yml

Contributing

Development install

Note: You will need NodeJS to build the extension package.

The jlpm command is JupyterLab's pinned version of yarn that is installed with JupyterLab. You may use yarn or npm in lieu of jlpm below.

# Clone the repo to your local environment
# Change directory to the jupyterlite-xeus-python directory
# Install package in development mode
python -m pip install -e ".[dev]"

# Link your development version of the extension with JupyterLab
jupyter labextension develop . --overwrite

# Rebuild extension Typescript source after making changes
jlpm run build

You can watch the source directory and run JupyterLab at the same time in different terminals to watch for changes in the extension's source and automatically rebuild the extension.

# Watch the source directory in one terminal, automatically rebuilding when needed
jlpm run watch
# Run JupyterLab in another terminal
jupyter lab

With the watch command running, every saved change will immediately be built locally and available in your running JupyterLab. Refresh JupyterLab to load the change in your browser (you may need to wait several seconds for the extension to be rebuilt).

Development uninstall

pip uninstall jupyterlite-xeus-python

In development mode, you will also need to remove the symlink created by jupyter labextension develop command. To find its location, you can run jupyter labextension list to figure out where the labextensions folder is located. Then you can remove the symlink named jupyterlite-xeus-python within that folder.

Packaging the extension

See RELEASE