SAK-42608 Samigo display user notifications for available assessments

[jkjanetschek]

This implementation does consider delays and exceptions for users/groups

[adrianfish]

I like this PR. You've delved into some challenging code here. So, apart from my pedantic commit suggestions I'd suggest that you add a service method for generating those event reference strings. I see that pattern repeated so many times in the samigo code base and it would be a great improvement if we made a method to return that reference.

[adrianfish]

Thanks, that'll do. Building those references, drying out that part of the code, that can wait. Thanks.

[jkjanetschek]

Thanks for your input and review!
Some repetition could easily be avoided, because many events in a code region use exactly the same reference. I can make another commit to increase the number of reference reuse, where it makes sense.

I am not sure how to approach a service method for reference building. For me it would make sense to place it in class AssessmentService. In a short search i found 6 possible references for events. Are there any missing?
Would it make sense to make just a service method with a switch-case block?

EVENT_ASSESSMENT_AVAILABLE
EVENT_ASSESSMENT_DELETE
EVENT_ASSESSMENT_UPDATE_AVAILABLE
EVENT_ASSESSMENT_PUBLISH
EVENT_PUBLISHED_ASSESSMENT_RETRACTED
siteId=, assessmentId=, publishedAssessmentId=
EVENT_PUBLISHED_ASSESSMENT_REPUBLISH
EVENT_PUBLISHED_ASSESSMENT_SETTING_EDIT
EVENT_PUBLISHED_ASSESSMENT_REMOVE
siteId=, publishedAssessmentId=
EVENT_ASSESSMENT_REMOVE
assessmentId=
EVENT_PUBLISHED_ASSESSMENT_SAVEITEM
/sam//publish, publishedItemId=
EVENT_ASSESSMENT_UNINDEXITEM
/sam//unindexed, itemId=
EVENT_PUBLISHED_ASSESSMENT_UNINDEXITEM
sam//unindexed, publishedItemId=

[adrianfish]

Don't worry about it for now. It's a refactor we can do later. Let's get your change in so it can be tested out. Thanks for the work - the notifications stuff has quite a few moving parts.