Jupyter Notebook Viewer

Overview

Fetch and display part of, or an entire Jupyter Notebook in an XBlock.

Jupyter is a "killer app" for education, said Prof. Lorena Barba in her keynote at the 2014 Scientific Python Conference (video available). Many people are writing lessons, tutorials, whole courses and even books using Jupyter. It is a new genre of open educational resource (OER). What if you want to create an online course on Open edX using content originally written as Jupyter notebook? You certainly don't want to duplicate the content, much less copy-and-paste. This XBlock allows you to embed the content dynamically from a notebook available on a public URL.

Prof. Barba used the XBlock in the second half of her course module, Get Data Off The Ground with Python. Check it out!

Installation

XBlock

login as the root user: sudo -i
New Installation:
- /edx/bin/pip.edxapp install git+https://github.com/ibleducation/jupyter-viewer-xblock.git
Re-Installation:
- /edx/bin/pip.edxapp install --upgrade --no-deps --force-reinstall git+https://github.com/ibleducation/jupyter-viewer-xblock.git
Restart the edxapp via /edx/bin/supervisorctl restart edxapp:

Edx Server Setup

In the studio, go to the course you would like to implement this XBlock in
Under Settings at the top, select Advanced Settings
in the Advanced Module List, add: "xblock_jupyter_viewer"
- ensure there is a comma after the second to last entry, and no comma exists after the last entry
Select Save

The viewer can now be added to a unit by selecting Jupyter Notebook Viewer from the Advanced component menu

LMS/CMS Setup

In the following two files:

/edx/app/edxapp/edx-platform/lms/urls.py
/edx/app/edxapp/edx-platform/cms/urls.py

Add the following to the bottom of each file:

# Jupyter Viewer XBlock Endpoint
urlpatterns += (
    url(r'^api/jupyter/', include('xblock_jupyter_viewer.rest.urls', 
                                  namespace='xblock_jupyter_viewer')),
)

In the following files:

/edx/app/edxapp/edx-platform/lms/envs/common.py
/edx/app/edxapp/edx-platform/cms/envs/common.py

Add the following at the bottom of the INSTALLED_APPS section:

    # Jupyter Notebook Viewer XBlock
    'xblock_jupyter_viewer',

Restart edxapp via /edx/bin/supervisorctl restart edxapp:

How it works

The XBlock contains an iframe that points to the REST endpoint.

The REST endpoint takes the following query parameters:

url: URL to the RAW jupyter notebook JSON file
start: (optional) text that starting cell contains
- if supplied, will start in FIRST cell that contains this text
- if not supplied, it starts at the beginning
end: (optional) text that ending cell contains
- if supplied, will end at FIRST cell that contains this text (not-inclusive - this cell is not shown)
- if not supplied, it will end at the end of the document
images_url: (optional) url to root of an images location (for <img> tags)
- if supplied, this will be pre-pended to the filename in the src attribute of all <img src=...> tags in the notebook
- example:
  - images_url :http://mysite.com/images/
  - <img src="/something/image.jpg"> becomes <img src="http://mysite.com/images/image.jp">

It is often easiest to use the markdown headers as the start/end tags, eg:

### My Start Header

If either start/end tags cannot be found in the document, they are ignored.

The REST endpoint returns the entire HTML + embedded CSS in order to be rendered in the XBlock iframe.

The user can also set the height of the XBlock in pixels in the Studio.

Pre/Post Processors

There are various pre and post processors that are applied to notebook when converting it to the final HTML.

Pre-Processors

These operate on each cell of the notebook, typically making some kind of change to either the overall notebook structure or a single cell.

The cells of the notebook are iterated over and each cell is passed to each processor in the sequence the processors are added.

After all cells have completed, the finish function is called for each processor to do any final cleanup.

New pre-processors can be added by subclassing preprocessors.Processor and appending an instance of it to the transforms list.

Post-Processors

These operate on the final, raw HTML output string, making modifications as necessary.

New post processors can be added in the postprocess function

Usage notes

Watch the demo!

Functionality

The Jupyter Viewer XBlock allows a course author to add content to an online course on the Open edX platform, from a publicly available Jupyter notebook (e.g., on GitHub). If you only provide one parameter, the notebook's public URL, the XBlock will display the entire notebook in an iframe. But it's often the case that instructors write Jupyter notebooks with a full lesson, over several pages if printed. Showing the whole notebook in one frame withing the online course may yield a clunky user experience. In our experience, your online course will look beter if you display a whole lesson over several units in an Open edX learning sequence. You can achieve this effect by choosing start and end tags: strings in the source notebook that mark the first and (exclusive) last cells to display. After choosing these tags, you may want to adjust the iframe height to fit the content length. If you have images embedded in markdown cells, you are likely to have a relative path that works in your local notebook. In the XBlock, you can provide the absolute path to the images in your notebook repo to ensure that they are properly shown.

iblai/jupyter-edx-viewer-xblock