Extending the Open edX platform sustainably through the Open edX Events and Filters framework
- Phillip Shiu (Deactivated)
Meta
Date: April 27, 2022 at 2:00pm, Room -115
Speaker: Felipe Montoya
Intro
GitHub - openedx/openedx-events: Open edX events from the Hooks Extensions Framework
GitHub - openedx/openedx-filters: Open edX filters from the Hooks Extensions Framework
Blended project led by edunext with edX as a collaborator.
Nutmeg will have the full implementation.
Hooks are a stable list of places in the life cycle of the learners and authors where externally defined functions can take place.
Example: Start > Register > Enroll > Learn > Certificate. Hooks can happen immediately before and after each of the >s.
Depending on what’s expected from them, there are two types of hooks: events and filters.
Events:
Features:
Doesn’t halt the application execution
Sent to receivers after performing an action
The main design goal of openedx-events is stability
They live in a separate Python library (openedx-events)
Definitions are versioned to increase their reliability
Documented with key information using in-line documentation
Implementation:
Open edX standardized Django signals
An event sends Data Attribute classes instead of in-memory obejcts
Events run in-process but the Event Bus will take them everywhere
The event bus is one of the reasons why they are named after the OEP-41
Filters:
Features:
Affect the application execution
Give the Open edX developer total control over the process where it runs, allowing them to manipulate in-memory objects
The main design goal of openedx-filters is flexibility
The definitions are documented with key information using in-line documentation
Definitions are versioned to increase reliability
Implementation:
They live in a separate Python library (openedx-filters)
Executes a list of functions just before performing an action
The filters tooling is based on a pipeline mechanism inspired by the Social Core pipeline
Named after OEP-41
Configured using Django settings
List of current event/filters
openedx-events/openedx_events/learning/signals.py at main · openedx/openedx-events
openedx-filters/openedx_filters/learning/filters.py at main · openedx/openedx-filters (still under implementation)
Example
How to create new events/filters
Creating an Open edX Event
Create the data attributes for the event (OEP-49)
Create the event definition
Integrate into service
Creating an Open edX Filter
Create the filter definition
Integrate into service