* feat: receiver for invalidate certificate
- consumes event of exam attempt rejected
- initial commit, need to make tests
* temp: moving consumer from signals to handlers.py
- Still need to make this work
- Need to make tests work too
* feat: refactored underlying code to api.py
- tests still need to be tweaked
* fix: commit history
* fix: improve api func name + add source param
[MICROBA-1075]
- Adds a new `edx.certificate.revoked` event to the LMS.
- Refactor of our certificate revocation functions in the GeneratedCertificate model.
This new event will be emit when a GeneratedCertificate with the status of `downloadable` is revoked (through the `invalidate(), mark_notpassing(), or mark_unverified() functions). Event will have a `source` field that will allow us how our certificates are being revoked from learners and can be broken down in the following way:
*Invalidate*
- allowlist_removal
- certificate_generation
- certificate_regeneration
- certificate_service
- certificate_invalidation_list
- bulk_certificate_regeneration
*mark_notpassing*
- certificate_generation
- notpassing_signal
*unverified*
- certificate_generation
