Add CourseService.get_members

lms/services/course.py

@@ -13,7 +13,10 @@
     CourseGroupsExportedFromH,
     Grouping,
     GroupingMembership,
+    LTIRole,
     Organization,
+    RoleScope,
+    RoleType,
     User,
 )
 from lms.product import Product
@@ -329,6 +332,24 @@ def get_assignments(
 
         return self._db.scalars(assignments_query).all()
 
+    def get_members(
+        self, course: Course, role_type: RoleType, role_scope: RoleScope
+    ) -> list[User]:
+        return self._db.scalars(
+            select(User)
+            .join(AssignmentMembership, User.id == AssignmentMembership.user_id)
+            .join(LTIRole)
+            .join(
+                AssignmentGrouping,
+                AssignmentMembership.assignment_id == AssignmentGrouping.assignment_id,
+            )
+            .where(
+                AssignmentGrouping.grouping_id == course.id,
+                LTIRole.scope == role_scope,
+                LTIRole.type == role_type,
+            )
+        ).all()
+
     def _get_authority_provided_id(self, context_id):
         return self._grouping_service.get_authority_provided_id(
             lms_id=context_id, type_=Grouping.Type.COURSE

tests/unit/lms/services/course_test.py

@@ -5,7 +5,12 @@
 from h_matchers import Any
 from sqlalchemy.exc import NoResultFound
 
-from lms.models import ApplicationSettings, CourseGroupsExportedFromH, Grouping
+from lms.models import (
+    ApplicationSettings,
+    CourseGroupsExportedFromH,
+    Grouping,
+    RoleScope,
+)
 from lms.product.product import Product
 from lms.services.course import CourseService, course_service_factory
 from tests import factories
@@ -338,6 +343,29 @@ def test_is_member(self, svc, db_session):
         assert svc.is_member(course, user.h_userid)
         assert not svc.is_member(course, other_user.h_userid)
 
+    def test_get_members(self, svc, db_session):
+        factories.User()  # User not in assignment
+        assignment = factories.Assignment()
+        user = factories.User()
+        course = factories.Course()
+        lti_role = factories.LTIRole(scope=RoleScope.COURSE)
+        factories.AssignmentMembership.create(
+            assignment=assignment, user=user, lti_role=lti_role
+        )
+        # User in assignment with other role
+        factories.AssignmentMembership.create(
+            assignment=assignment,
+            user=factories.User(),
+            lti_role=factories.LTIRole(scope=RoleScope.SYSTEM),
+        )
+        factories.AssignmentGrouping(grouping=course, assignment=assignment)
+
+        db_session.flush()
+
+        assert svc.get_members(
+            course, role_scope=lti_role.scope, role_type=lti_role.type
+        ) == [user]
+
     def test_get_organization_courses_deduplicates(self, db_session, svc):
         org = factories.Organization()