JupyterLab Freeze (Improved)

WORK IN PROGRESS!

An opinionated version of DataDog/jupyterlab-freeze.

Allows you to freeze cells in JupyterLab notebooks. This can be useful in teaching enviroments, where students can be prevented from accidentally altering code cells, or viewing the source of markdown cells that are meant purely for reading. Forked from https://github.com/DataDog/jupyterlab-freeze.

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This extension allows to make cells read-only or frozen. It provides three buttons:

Namely:

• Unlocked
• Read-only
• Frozen

For code cells:

• Unlocked: The cell behaves normally.
• Read-only: The cell can be executed, but its input cannot be changed.
• Frozen: The cell cannot be edited, deleted, or executed.

For markdown cells:

• Unlocked: The cell behaves normally.
• Read-only: Cell markdown source can be viewed by double-clicking on it, but cannot be changed. The cell also cannot be deleted.
• Frozen: Cell input cannot be viewed by double-clicking on it. The cell cannot be deleted.

The individual cell's state is stored in its metadata and is applied to the cell if the extension is loaded.

Requirements

• JupyterLab >= 4.0.0

Install

To install the extension, execute:

pip install jupyterlab_freeze_improved

Uninstall

To remove the extension, execute:

pip uninstall jupyterlab_freeze_improved

JupyterHub

If you are deploying JupyterHub for the purposes of teaching, this extension can be installed for all current or future users using pip.

Typically, you will have installed JupyterHub in a virtual environment (named jupyterhub in the examples below).

Therefore, to install jupyterlab_freeze_improved for all users, first ensure you are in your virtual environment (in this case, located in /opt/jupyterhub):

$ source /opt/jupyterhub/bin/activate

and then install jupyterlab_freeze_improved using pip:

(jupyterhub)$ pip install jupyterlab_freeze_improved

You can view all installed/enabled extensions, as follows:

(jupyterhub)$ jupyter labextension list

this will output something similar to:

JupyterLab v4.2.5
/opt/jupyterhub/share/jupyter/labextensions
        jupyterlab_freeze_improved v1.0.0 enabled OK (python, jupyterlab_freeze_improved)
        jupyterlab_pygments v0.3.0 enabled OK (python, jupyterlab_pygments)
        @jupyter-notebook/lab-extension v7.2.2 enabled OK
        @jupyter-widgets/jupyterlab-manager v5.0.13 enabled OK (python, jupyterlab_widgets)

See https://jupyterlab.readthedocs.io/en/4.2.x/user/extensions.html for more information.

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 jupyterlab_freeze_improved directory
# Install package in development mode
pip install -e "."
# Link your development version of the extension with JupyterLab
jupyter labextension develop . --overwrite
# Rebuild extension Typescript source after making changes
jlpm 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 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).

By default, the jlpm build command generates the source maps for this extension to make it easier to debug using the browser dev tools. To also generate source maps for the JupyterLab core extensions, you can run the following command:

jupyter lab build --minimize=False

Development uninstall

pip uninstall jupyterlab_freeze_improved

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 jupyterlab_freeze_improved within that folder.

Testing the extension

Frontend tests

This extension is using Jest for JavaScript code testing.

To execute them, execute:

jlpm
jlpm test

Integration tests

This extension uses Playwright for the integration tests (aka user level tests). More precisely, the JupyterLab helper Galata is used to handle testing the extension in JupyterLab.

More information are provided within the ui-tests README.

Packaging the extension

See RELEASE

Notes

The DataDog/jupyterlab-freeze extension is based on the freeze extension by jupyter_contrib_nbextensions.