ipycomms

This module is a thin wrapper around the ipykernel.comms functionality, providing lightweight bidirectional messaging between Python in an IPython (Jupyter) notebook and Javascript running in the notebook output.

Messaging is oriented around topics (arbitrary strings) and doesn't require establishing a channel before sending / receiving messages. Messages on unhandled topics are ignored.

This is a fairly low-level way to get Javascript to work with your notebook. You should see if IPython.notebook.kernel.execute or widgets / interact would better suit your needs.

Installation

pip install ipycomms

Usage

In your notebook, on the Python side:

# This will setup kernel-side handlers and inject some Javascript into your notebook.
import ipycomms

# A handler which will echo back messages.
def print_message(msg):
    # (Useful trick -- if you want to print things in handler functions normal stdout / notebook output
    #  won't do the trick. The easiest thing I've found is to steal the kernel logger, which goes to
    #  the IPython kernel stdout.)
    get_ipython().kernel.log.warn(msg)
    
    ipycomms.send('some.topic', msg)

# Register a listener
ipycomms.setListener('some.topic', print_message)

Javascript (this example is for a notebook cell -- in practice it would probably be used somewhere in injected code):

%%javascript
// Print messages sent to "some.topic"
IPython.ipycomms.setListener("some.topic", function(data){
    console.log(data)
})

// Send a message
IPython.ipycomms.send("some.topic", [1,2,3])