perf: migrate single-call Document permission sites to permitted_document_ids (#13507)

* perf: migrate 5 single-call Document permission sites to permitted_document_ids

Swaps get_objects_for_user_owner_aware(user, "view_document", Document) for
Document.objects.filter(id__in=permitted_document_ids(user)) at 5 read-only,
single-call sites: AI chat "ask all documents", bulk-edit
_resolve_document_ids all:true branch, SelectionDataView permission check,
global search docs bucket, and the statistics endpoint's Document branch.

Confirmed all 3 callers of _resolve_document_ids always use the default
"view_document" codename before swapping. Added a regression test pinning
the AI-chat owner/permission boundary through the real API client, and
updated 2 existing mocked tests in test_views.py that asserted on
get_objects_for_user_owner_aware for the chat endpoint.

* perf: migrate 3 serialisers.py Document permission sites to permitted_document_ids

Migrates _get_viewable_duplicates(), PaperlessTaskSerializer.get_duplicate_documents(),
and the ShareLinkBundle document field queryset to use permitted_document_ids()
instead of get_objects_for_user_owner_aware()/get_objects_for_user(), consolidating
onto the shared permission-filtering helper. The is_staff gate in
get_duplicate_documents() is preserved as-is.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GRp4kf1mdn9ruv81zWAmh2

* refactor: remove dead permission_codename param from _resolve_document_ids

The keyword param was unused in the method body since an earlier commit
switched it to call permitted_document_ids(user) internally. None of the
3 call sites passed it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* docs: drop internal task-number reference from AI chat migration test docstring

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

src/documents/tests/test_permission_filtering_security.py

@@ -1,12 +1,18 @@
 from __future__ import annotations
 
+from unittest.mock import patch
+
 import pytest
 from django.contrib.auth.models import AnonymousUser
 from django.contrib.auth.models import Group
+from django.contrib.auth.models import Permission
 from django.contrib.auth.models import User
+from django.test import override_settings
 from guardian.shortcuts import assign_perm
+from rest_framework.test import APIClient
 
 from documents.permissions import permitted_document_ids
+from documents.serialisers import _get_viewable_duplicates
 from documents.tests.factories import DocumentFactory
 
 
@@ -151,3 +157,63 @@ class TestPermittedDocumentIdsIncludeDeleted:
             expected_visible=[],
             expected_hidden=[doc.pk],
         )
+
+
+@pytest.mark.django_db
+class TestAiChatAllDocumentsPermissionBoundary:
+    """
+    Regression test pinning the "ask across all documents" AI chat behavior
+    (ChatStreamingView.post, no document_id) to the same owner/permission
+    boundary enforced by permitted_document_ids(). This call site was
+    migrated from get_objects_for_user_owner_aware() to
+    permitted_document_ids(); this test must stay green across that swap.
+    """
+
+    ENDPOINT = "/api/documents/chat/"
+
+    @override_settings(AI_ENABLED=True)
+    @patch("documents.views.stream_chat_with_documents")
+    def test_chat_all_documents_excludes_unshared_document(self, mock_stream_chat):
+        mock_stream_chat.return_value = iter([b"data"])
+
+        owner = User.objects.create_user(username="owner")
+        asker = User.objects.create_user(username="asker")
+        asker.user_permissions.add(
+            *Permission.objects.filter(codename="view_document"),
+        )
+        shared = DocumentFactory(owner=owner)
+        not_shared = DocumentFactory(owner=owner)
+        assign_perm("view_document", asker, shared)
+
+        client = APIClient()
+        client.force_authenticate(user=asker)
+        response = client.post(
+            self.ENDPOINT,
+            data={"q": "question"},
+            format="json",
+        )
+
+        assert response.status_code == 200
+        mock_stream_chat.assert_called_once()
+        _, kwargs = mock_stream_chat.call_args
+        visible_ids = {doc.pk for doc in kwargs["documents"]}
+        assert shared.pk in visible_ids
+        assert not_shared.pk not in visible_ids
+
+
+@pytest.mark.django_db
+class TestDuplicateDocumentsPermissionBoundary:
+    def test_get_viewable_duplicates_includes_soft_deleted_but_respects_perms(self):
+        owner = User.objects.create_user(username="owner")
+        stranger = User.objects.create_user(username="mallory")
+        original = DocumentFactory(owner=owner, checksum="dupe-checksum")
+        dup_visible = DocumentFactory(owner=owner, checksum="dupe-checksum")
+        dup_hidden = DocumentFactory(owner=owner, checksum="dupe-checksum")
+        dup_hidden.delete()  # soft delete, should still be found (include_deleted=True)
+        assign_perm("view_document", stranger, dup_visible)
+
+        result_owner = _get_viewable_duplicates(original, owner)
+        assert {d.pk for d in result_owner} == {dup_visible.pk, dup_hidden.pk}
+
+        result_stranger = _get_viewable_duplicates(original, stranger)
+        assert {d.pk for d in result_stranger} == {dup_visible.pk}

src/documents/tests/test_views.py

@@ -648,11 +648,11 @@ class TestAIChatStreamingView(DirectoriesMixin, TestCase):
         self.assertIn(b"AI is required for this feature", response.content)
 
     @patch("documents.views.stream_chat_with_documents")
-    @patch("documents.views.get_objects_for_user_owner_aware")
+    @patch("documents.views.permitted_document_ids")
     @override_settings(AI_ENABLED=True)
-    def test_post_no_document_id(self, mock_get_objects, mock_stream_chat) -> None:
+    def test_post_no_document_id(self, mock_permitted_ids, mock_stream_chat) -> None:
         self.grant_view_document_permission()
-        mock_get_objects.return_value = [self.document]
+        mock_permitted_ids.return_value = [self.document.pk]
         mock_stream_chat.return_value = iter([b"data"])
         response = self.client.post(
             self.ENDPOINT,
@@ -661,23 +661,23 @@ class TestAIChatStreamingView(DirectoriesMixin, TestCase):
         )
         self.assertEqual(response.status_code, 200)
         self.assertEqual(response["Content-Type"], "text/event-stream")
-        mock_stream_chat.assert_called_once_with(
-            query_str="question",
-            documents=[self.document],
-            output_language=None,
-        )
+        mock_stream_chat.assert_called_once()
+        call_kwargs = mock_stream_chat.call_args.kwargs
+        self.assertEqual(call_kwargs["query_str"], "question")
+        self.assertEqual(list(call_kwargs["documents"]), [self.document])
+        self.assertIsNone(call_kwargs["output_language"])
 
     @patch("documents.views.stream_chat_with_documents")
-    @patch("documents.views.get_objects_for_user_owner_aware")
+    @patch("documents.views.permitted_document_ids")
     @override_settings(AI_ENABLED=True)
     def test_post_uses_user_display_language(
         self,
-        mock_get_objects,
+        mock_permitted_ids,
         mock_stream_chat,
     ) -> None:
         UiSettings.objects.create(user=self.user, settings={"language": "de-de"})
         self.grant_view_document_permission()
-        mock_get_objects.return_value = [self.document]
+        mock_permitted_ids.return_value = [self.document.pk]
         mock_stream_chat.return_value = iter([b"data"])
 
         response = self.client.post(
@@ -687,11 +687,11 @@ class TestAIChatStreamingView(DirectoriesMixin, TestCase):
         )
 
         self.assertEqual(response.status_code, 200)
-        mock_stream_chat.assert_called_once_with(
-            query_str="question",
-            documents=[self.document],
-            output_language="de-de",
-        )
+        mock_stream_chat.assert_called_once()
+        call_kwargs = mock_stream_chat.call_args.kwargs
+        self.assertEqual(call_kwargs["query_str"], "question")
+        self.assertEqual(list(call_kwargs["documents"]), [self.document])
+        self.assertEqual(call_kwargs["output_language"], "de-de")
 
     @patch("documents.views.stream_chat_with_documents")
     @override_settings(AI_ENABLED=True)