derby-notebook

A proof of concept of providing a multi-user Jupyter notebook.

The approach is to run a proxy over the notebook server and intercept the notebooks requests, replacing them with a Derby app on top of the running state IPython notebook.

In the background, a listener waits for changes on the model, and transforms them into messages, and similarly updates the model when it receives messages.

Roadmap

• proxy notebook
• Load content into multiuser view (after single-user bootstrap)
• open websocket connection to kernel
• multiuser codemirror in cells
• add cell above/below current
• move cell up/down
• remove cell
• run cell, see output
• multiuser presence, (chat, meh)
• overload /notebooks (and all calls to start up kernel)
• post contents back to content manager API
• wrap widgets in derby model

Model

A Derby model is a set of collections of JSON-compatible documents. The main collection is notebooks, which includes, of course, the notebook contents, but several other pieces to enable a multi-user experience:

{
  // The filename, as would be used in /notebooks/Untitled.ipynb
  "name": "Untitled.ipynb",
  // the results of the contents manager
  "contents": {},
  // stuff for connecting to kernel
  "session": {}
}

When one of these documents are created, a derby-hook goes off an grabs the contents, and populates the cells collection. Each cell is its own standalone document to keep updates more atomic. _ keys will be stripped out when being posted back to the

{
  "cell_type": "markdown" // or code
  "source": "the code or text",
  "outputs": [],
  // ... more cell stuff
  "id": "generated-by-derby"
  "_state": "run" // probably a better way to do this
  "_editors": {
    "userid": 1
  },
  "_notebook": "the notebook id",
  "_weight": 1000 // heavier weights sink to the bottom of the page
}

Running

This is all lashed together with docker-compose, and presently also runs inside a vagrant box.

vagrant up

Then, log into that box.

Build (this can take a while!) and run everything with:

docker-compose up

Then visit http://localhost:9999/

Or, if you just want to restart the proxy:

docker-compose build && docker-compose start && docker-compose logs
^C
docker-compose build && docker-compose restart proxy && docker-compose logs

Debugging node stuff

start an interactive coffeescript shell

docker run -i vagrant_proxy