feat: Implement courses roles and permissions mappings

[rodmgwgu]

Implemented courses roles and permissions mappings, including legacy compatible permissions and role equivalences.

Permissions implemented as specified here: https://openedx.atlassian.net/wiki/spaces/OEPM/pages/5528715266/openedx-authz+permission+list

Roles implemented as specified here: https://openedx.atlassian.net/wiki/spaces/OEPM/pages/5638619138/Authoring+Roles+and+Permissions

Equivalent legacy roles implemented as specified here: https://github.com/rodmgwgu/openedx-authz/blob/385e76d4e95381bb6533df5272ecff6593e09156/docs/decisions/0011-course-authoring-migration-process.rst

Closes: #189

Required for: openedx/openedx-platform#38013

Merge checklist:
Check off if complete or not applicable:

• Version bumped
• Changelog record added
• Documentation updated (not only docstrings)
• Fixup commits are squashed away
• Unit tests added/updated
• Manual testing instructions provided
• Noted any: Concerns, dependencies, migration issues, deadlines, tickets

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[wgu-taylor-payne]

This looks good. Just one comment regarding the version number.

[wgu-taylor-payne]

I think this would be a minor bump to 0.22.0 since it is adding functionality rather than bug fixes.

[rodmgwgu]

done, thanks!

[dwong2708]

LGTM, just one suggestion in the legacy roles mapping.

[dwong2708]

Is it possible to reverse the mapping order?

For example:

{
    COURSE_ADMIN.external_key: "instructor",
    ...
}

Reason: while working on the migration, during rollback (authz → legacy), I only have access to new_role.key, so I need a way to map it back to the corresponding legacy role.

[rodmgwgu]

This is how I'm doing it in openedx-platform: https://github.com/WGU-Open-edX/openedx-platform/blob/5dc65a27a4cfc9f8045ab71fca19965f7127f488/common/djangoapps/student/roles.py#L39

I also need it both ways there, I did it that way to avoid having to maintain two maps, what do you think?

[dwong2708]

Sounds good, just one consideration.

If we have a mapping like:

{
    "instructor": "admin",
    "staff": "admin",
}

get_legacy_role_from_authz_role would just pick the first match. Not sure if this case is expected, but maybe we should add a comment here or in the function to clarify the behavior.

[rodmgwgu]

mmm where do you see that? instructor is "admin" but staff should be "staff" as documented here: https://github.com/rodmgwgu/openedx-authz/blob/385e76d4e95381bb6533df5272ecff6593e09156/docs/decisions/0011-course-authoring-migration-process.rst (Role Mapping table)

[dwong2708]

Quick question: should detail be a separate permission?

Not sure if it belongs in the same section, but the docs say view_details is used for viewing course details.

[rodmgwgu]

This was a discussion I had with Guillermo, the Schedule and Details view is a single view, separating the permissions would require extra changes in frontend that are not really needed, so a single permission was proposed, the docs may not be updated

[wgu-taylor-payne]

Something else came to mind. I think that some of these constant names could be more descriptive. Since we have library related permissions, course permissions, and in the future other permissions in this file, it would be good to rename some of these like EDIT_DETAILS, VIEW_FILES, etc. to show somehow that they are course related. Another option would be to scope the various permission namespaces to their own modules (e.g. course_permissions.py, library_permissions.py).