support checking admin teachers

codeforlife/user/permissions/is_student.py

@@ -19,8 +19,8 @@ def __init__(self, student_id: t.Optional[int] = None):
         """Initialize permission.
 
         Args:
-            student_id: A student's ID. If passed, the user must be this
-                student.
+            student_id: A student's ID. If None, check if the user is any
+                student. Else, check if the user is the specific student.
         """
 
         super().__init__()

codeforlife/user/permissions/is_teacher.py

@@ -9,27 +9,39 @@
 from rest_framework.request import Request
 from rest_framework.views import APIView
 
-from ..models import User
+from ..models import Teacher, User
 
 
 class IsTeacher(BasePermission):
     """Request's user must be a teacher."""
 
-    def __init__(self, teacher_id: t.Optional[int] = None):
+    def __init__(
+        self,
+        teacher_id: t.Optional[int] = None,
+        is_admin: t.Optional[bool] = None,
+    ):
         """Initialize permission.
 
         Args:
-            teacher_id: A teacher's ID. If passed, the user must be this
-                teacher.
+            teacher_id: A teacher's ID. If None, check if the user is any
+                teacher. Else, check if the user is the specific teacher.
+            is_admin: If the teacher is an admin. If None, don't check if the
+                teacher is an admin. Else, check if the teacher is (not) an
+                admin.
         """
 
         super().__init__()
         self.teacher_id = teacher_id
+        self.is_admin = is_admin
 
     def has_permission(self, request: Request, view: APIView):
         user = request.user
         return (
             isinstance(user, User)
             and user.teacher_id is not None
             and (self.teacher_id is None or user.teacher_id == self.teacher_id)
+            and (
+                self.is_admin is None
+                or t.cast(Teacher, user.teacher).is_admin == self.is_admin
+            )
         )