Class Module

Location: backend/src/class/

The class module manages student groups (classes) and their teacher assignments. A "class" in the system is represented as a student_group in the database. Each class belongs to an academic year and has one class teacher who has full control, plus optional subject teachers.

Files

File	Purpose
class.module.ts	Module definition; exports ClassTeacherGuard
class.controller.ts	API endpoints
class.service.ts	Business logic
class-teacher.guard.ts	Authorization guard for class teacher operations
dto/create-class.dto.ts	Validation for creation
dto/update-class.dto.ts	Validation for updates
dto/add-teacher.dto.ts	Validation for teacher assignment

Data Model

Student Group (Class)

Field	Type	Description
id	UUID	Primary key
name	string	Class name (e.g., "Grade 3S")
academic_year_id	UUID	The academic year this class belongs to
created_by	UUID	User who created the class

Teacher Group Assignment (staff schema)

Field	Type	Description
user_profile_id	UUID	Teacher's user profile
student_group_id	UUID	The class
academic_year_id	UUID	Academic year
is_class_teacher	boolean	Whether this teacher is the class teacher

Teacher Subject Assignment (staff schema)

Field	Type	Description
user_profile_id	UUID	Teacher's user profile
subject_id	UUID	The subject they teach
student_group_id	UUID	The class
academic_year_id	UUID	Academic year

ClassTeacherGuard

The ClassTeacherGuard restricts certain actions to the class teacher (or an admin). It reads the :classId route parameter and checks teacher_group_assignment for is_class_teacher = true.

Access logic:

1. Check user_profile.role - if admin, allow
2. Check teacher_group_assignment for this user + class - if is_class_teacher, allow
3. Otherwise, reject with 403 Forbidden

Roles and Visibility

Role	Can See Classes	Can Modify Class	Can Manage Teachers
Admin	All	Yes	Yes
Class Teacher	Their assigned classes	Yes (their own)	Yes (their own)
Subject Teacher	Classes they teach in	No	No

API Endpoints

All endpoints require AuthGuard.

GET /api/classes

Returns all classes the authenticated user is assigned to (as class teacher or subject teacher).

Query Parameters:

Param	Required	Description
academicYearId	No	Filter by academic year

Response: Array of class objects with isClassTeacher flag:

[
  {
    "id": "uuid",
    "name": "Grade 3S",
    "academicYearId": "uuid",
    "isClassTeacher": true
  }
]

---

POST /api/classes

Creates a new class. The creator is automatically assigned as the class teacher.

Body:

{
  "name": "Grade 3S",
  "academicYearId": "uuid",
  "subjectIds": ["uuid1", "uuid2"]
}

The optional subjectIds array assigns subjects to the class teacher during creation.

---

GET /api/classes/:classId

Returns a single class by ID.

---

PATCH /api/classes/:classId

Requires: ClassTeacherGuard

Updates the class name.

---

DELETE /api/classes/:classId

Requires: ClassTeacherGuard

Deletes the class and all associated data.

---

GET /api/classes/:classId/my-subjects

Returns the subjects the current user can grade for this class.

Access logic:

• Admin or class teacher → all subjects in the school
• Subject teacher → only the subjects they're assigned to teach in this class

This endpoint is used by the grading page to populate the subject dropdown.

---

GET /api/classes/:classId/teachers

Returns all teachers assigned to this class with their subjects.

Response:

[
  {
    "teacherId": "uuid",
    "firstName": "John",
    "lastName": "Smith",
    "isClassTeacher": true,
    "subjects": [
      { "id": "uuid", "name": "Mathematics", "code": "MATH" }
    ]
  }
]

---

POST /api/classes/:classId/teachers

Requires: ClassTeacherGuard

Adds a teacher to the class or updates their subject assignments. If the teacher is already assigned, their subjects are replaced.

Body:

{
  "teacherId": "uuid",
  "subjectIds": ["uuid1", "uuid2"]
}

---

DELETE /api/classes/:classId/teachers/:teacherId

Requires: ClassTeacherGuard

Removes a teacher from the class. Cannot remove the class teacher - returns 403 Forbidden.

---

GET /api/classes/school-teachers

Returns all teachers in the same school as the current user. Used when assigning teachers to a class.