🐛(backend) prevent privileged users from requesting access

Privileged users of a document (owners and admins) should not be
allowed to create an access request on a document they already control.
Without aguardrail, they could inadvertently inflate the access
request queue with redundant entries.

More critically, if an owner submits an access request on their own
document, another admin could accept it and grant them a lower role
(e.g. reader), which would silently strip them of their ownership.

Signed-off-by: Mohamed El Amine BOUKERFA <[email protected]>

CHANGELOG.md

@@ -53,7 +53,7 @@ and this project adheres to
 - ♿️(frontend) add focus on open to modals #1948
 
 ### Fixed
-
+- 🐛 (backend) prevent privileged users from requesting access #1898
 - 🐛(frontend) fix broadcast store sync #1846
 - 🐛(helm) use celery resources instead of backend resources #1887
 - 🐛(helm) reverse liveness and readiness for backend deployment #1887

src/backend/core/api/viewsets.py

@@ -2523,6 +2523,12 @@ class DocumentAskForAccessViewSet(
         """Create a document ask for access resource."""
         document = self.get_document_or_404()
 
+        if document.get_role(request.user) in models.PRIVILEGED_ROLES:
+            return drf.response.Response(
+                {"detail": "You already have privileged access to this document."},
+                status=drf.status.HTTP_400_BAD_REQUEST,
+            )
+
         serializer = serializers.DocumentAskForAccessCreateSerializer(data=request.data)
         serializer.is_valid(raise_exception=True)
 

src/backend/core/tests/documents/test_api_documents_ask_for_access.py

@@ -9,6 +9,7 @@ import pytest
 from rest_framework.test import APIClient
 
 from core.api.serializers import UserSerializer
+from core.choices import PRIVILEGED_ROLES
 from core.factories import (
     DocumentAskForAccessFactory,
     DocumentFactory,
@@ -199,6 +200,27 @@ def test_api_documents_ask_for_access_create_authenticated_already_has_ask_for_a
     assert response.json() == {"detail": "You already ask to access to this document."}
 
 
+@pytest.mark.parametrize("role", PRIVILEGED_ROLES)
+def test_api_documents_ask_for_access_create_authenticated_already_has_privileged_access(
+    role,
+):
+    """
+    Authenticated users with privileged access (owner or admin) should not be able to
+    create a document ask for access.
+    """
+    user = UserFactory()
+    document = DocumentFactory(users=[(user, role)])
+
+    client = APIClient()
+    client.force_login(user)
+
+    response = client.post(f"/api/v1.0/documents/{document.id}/ask-for-access/")
+    assert response.status_code == 400
+    assert response.json() == {
+        "detail": "You already have privileged access to this document."
+    }
+
+
 ## List