Simon Willison’s Weblog


Weeknotes: datasette-jupyterlite, s3-credentials and a Python packaging talk

5th November 2021

My big project this week was s3-credentials, described yesterday—but I also put together a fun expermiental Datasette plugin bundling JupyterLite and wrote up my PyGotham talk on Python packaging.


JupyterLite is absolutely incredible: it’s a full, working distribution of Jupyter that runs entirely in a browser, thanks to a Python interpreter (and various other parts of the scientific Python stack) that has been compiled to WebAssembly by the Pyodide project.

Since it’s just static JavaScript (and WASM modules) it’s possible to host it anywhere that can run a web server.

Datasette runs a web server...

So, I built datasette-jupyterlite—a Datasette plugin that bundles JupyterLite and serves it up as part of the Datasette instance.

You can try a live demo here:

Screenshot showing JupyterLite hosted by Datasette

Here’s some Python code that will retrieve data from the associated Datasette instance and pull it into a Pandas DataFrame:

import pandas, pyodide

(I haven’t yet found a way to do this with a relative rather than absolute URL.)

The best part of this is that it works in Datasette Desktop! You can install the plugin using the “Install and manage plugins” menu item to get a version of Jupyter running in Python running in WebAssembly running in V8 running in Chromium running in Electron.

The plugin implementation is just 30 lines of code—it uses the jupyterlite Python package which bundles a .tgz file containing all of the required static assets, then serves files directly out of that tarfile.

Also this week

My other projects from this week are already written about on the blog:

Releases this week

TIL this week