feat: add event bus backend

[Ian2012]

Description

This PR creates a backend to emit the Open edX signal defined in openedx/openedx-events#230.

Testing instructions

• Install openedx-events from the mentioned PR
• Install event-tracking from this branch
• Add the following setting:

EVENT_TRACKING_BACKENDS = {
    'xapi': {
        'ENGINE':  'eventtracking.backends.event_bus.EventBusRoutingBackend',
        'OPTIONS': { ## Not sure if this is needed
            'backend_name': 'xapi',
            'processors': [
                {
                }
            ],
     },
   },
}

• Listen to the emitted signal and verify the data is received correctly for all the events.

For reference, here is the consumer code:

@receiver(TRACKING_EVENT_EMITTED)
def listen_for_tracking_event_emitted_event(sender, signal, **kwargs):
    """
    Prints `TRACKING_EVENT_EMITTED` events.
    """
    print("\n\n", kwargs, "\n\n")

[openedx-webhooks]

Thanks for the pull request, @Ian2012! Please note that it may take us up to several weeks or months to complete a review and merge your PR.

Feel free to add as much of the following information to the ticket as you can:

• supporting documentation
• Open edX discussion forum threads
• timeline information ("this must be merged by XX date", and why that is)
• partner information ("this is a course on edx.org")
• any other information that can help Product understand the context for the PR

All technical communication about the code itself will be done via the GitHub pull request interface. As a reminder, our process documentation is here.

This is currently a draft pull request. When it is ready for our review and all tests are green, click "Ready for Review", or remove "WIP" from the title, as appropriate.

[bmtcril]

Can you add some basic tests like the async backend has? I think this will also require openedx-events in base.in requirements now as well.

[Ian2012]

@bmtcril There are some tests implemented now, it will fail till the openedx signal is merged

[mphilbrick211]

Hi @Ian2012 - checking in to see if you plan to pursue this pull request?

[mphilbrick211]

Closing this PR due to inactivity.

[openedx-webhooks]

@Ian2012 Even though your pull request wasn’t merged, please take a moment to answer a two question survey so we can improve your experience in the future.

[openedx-webhooks]

@Ian2012 Even though your pull request wasn’t merged, please take a moment to answer a two question survey so we can improve your experience in the future.