Backend: Course assignment API endpoints

[rtibbles]

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Overview

Create REST API endpoints for managing course assignments in the kolibri/core/courses/ app, following the pattern established by Lesson and Exam viewsets.

Implementation

Files to create/modify:

1. kolibri/core/courses/viewsets.py

   • Create CourseAssignmentSerializer
   • Create CourseAssignmentViewSet with KolibriAuthPermissions
   • Filter queryset to only show assignments for accessible collections

2. kolibri/core/courses/api_urls.py

   • Register CourseAssignmentViewSet with router
   • Register URLs in main Kolibri API configuration

3. kolibri/core/courses/test/test_api.py

   • Test CRUD operations
   • Test permission checks (coaches/admins can manage, learners cannot)
   • Test collection filtering (users only see their accessible assignments)
   • Test 400 error when assignment references non-existent ContentNode

Key Requirements

1. Use KolibriAuthPermissions - Defers to model's RoleBasedPermissions

2. Handle missing courses - Return semantic 400 error when assignment references a ContentNode that doesn't exist on the device

3. Filter by collection access - Users only see assignments for collections they can access

API Endpoints

• GET /api/courseassignment/ - List assignments
• POST /api/courseassignment/ - Create assignment
• GET /api/courseassignment/{id}/ - Get assignment
• PATCH /api/courseassignment/{id}/ - Update assignment
• DELETE /api/courseassignment/{id}/ - Delete assignment

References

• Lessons viewsets: kolibri/core/lessons/viewsets.py
• Lessons tests: kolibri/core/lessons/test/test_lesson_api.py
• KolibriAuthPermissions: kolibri/core/auth/api.py