feat: add course wide notification event for notifications having wider audience

[saadyousafarbi]

INF-1134

Description

Context

This PR introduces a new handler for the new COURSE_NOTIFICATION_REQUESTED event.
The event will be fired whenever a notification is requested for a course-wide audience.
Some examples of notifications that can be requested via this event:

• Course updates to all verified learners,
• Marketing updates to all audit learners to upgrade course,
• Reported content from discussions sent out to all moderators.

The event will contain 2 important components for determining the audience of the notification, course_key (identify the course) and the audience_filters (how to filter the audience within the course).

Working

the audience_filters will be a dict containing keys that represent the type of audience to filter, and the list of values as value to specify type of filter to apply to that specific audience.

The supported audience_filters we have right now are role and enrollment.

Usage of Role filter

{
    ...,
    "audience_filters": {
            "role": ["Moderator"],
        }
}

Notification sent out to all moderators within the specified course.

Usage of Enrollment filter

{
    ...,
    "audience_filters": {
            "enrollment": ["verified", "audit"],
        }
}

Notification sent out to all learner with enrollment mode verified or audit within the specified course.

Combination of filters

We also support combination of filters i.e, we can have multiple filters at the same time. Following is an example:

{
    ...,
    "audience_filters": {
            "enrollment": ["verified"],
            "role": ["Moderator"],
        }
}

This means that we will first fetch the users within course that have the enrollment mode verified and then fetch users with role Moderator.

The notification will be sent out to all verified learners, and moderators within the course.

❗ if the audience_filters is empty (no filter specified), the notification will be sent out to all active enrolled learners within the course.

Followups

• Separate discussions roles filter and course roles filter
• Add cohort filter class
• Use this new handler to handle notification for new_discussion_post and new_question_post

Related PRs

openedx/openedx-events#285

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX staging environment in preparation for a release to production.

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX production environment.

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX production environment.