Remove max_submissions from the assessment interface

[raphendyr]

Currently, A+ sends provides field max_submissions to an assessment service: https://github.com/apluslms/a-plus/blob/0cf8c3126d6011f08201764c3878b930ec4f3e31/exercise/exercise_models.py#L738

For now, this seems to be used only to show model answer in MOOC-Grader after all submissions are consumed:

1. https://github.com/apluslms/mooc-grader/blob/a5b74f67c2261159b9368d4df9081796b813d509/access/types/stdsync.py#L104
2. https://github.com/apluslms/mooc-grader/blob/a5b74f67c2261159b9368d4df9081796b813d509/access/types/forms.py#L38
3. https://github.com/apluslms/mooc-grader/blob/a5b74f67c2261159b9368d4df9081796b813d509/access/templates/access/graded_form.html#L128

However, this information may change at any time. In addition, we currently do not take in account any deviations to this, so if the user has 6 submissions, when exercise has 5 by default, then the user will see the model solution after the 5th submission and can then use model to answer correctly.

Furthermore, the data-aplus-once should be removed too, and can be done as part of this issue, as the feature is only used in addition to the main feature.

We should make it so that the access to the model is handled by the A+. Hence, the "show model answer" button should be usable only when the user has reached the max submissions limit.

This feature can be just dropped and implemented again if it's really needed. Alternatively, this issue may be blocked, until there is a implementation for this in the A+.

• [ ] Remove max_submissions (can be dropped, was not part of the documented API)
• [ ] Remove reveal_answer from the MOOC-Grader
• [ ] Remove data-aplus-once
• [ ] Remove data-aplus-once from the MOOC-Grader

Check following services for required changes:

• [ ] https://github.com/acos-server/acos-server
• [ ] https://github.com/aalto-letech/rubyric
• [ ] https://github.com/piehei/prplatform/
• [ ] https://github.com/eliisav/gradinghelper/

[markkuriekkinen]

Before max_submissions is dropped, it is best to also check that the Acos server or Rubyric do not use the parameter.

[raphendyr]

I didn't find max_submissions with github search from any of the 4 assessment services, but it's still better to verify better.

[markkuriekkinen]

This issue was created over three years ago and before anything is done about this, we should consider "the big picture" more carefully first.