Tests: add regression test for redis URL with empty username (#12460)

* Tests: add regression test for redis URL with empty username and password

Covers the unix://:SECRET@/path.sock format (empty username, password only),
which was missing from the existing test cases for PR #12239.

* Update src/paperless/tests/settings/test_custom_parsers.py

---------

Co-authored-by: shamoon <4887959+shamoon@users.noreply.github.com>

src/documents/tests/test_api_objects.py

@@ -360,7 +360,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "path/Something")
+        self.assertEqual(response.data, "path/Something.pdf")
 
     def test_test_storage_path_respects_none_placeholder_setting(self) -> None:
         """
@@ -390,7 +390,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "folder/none/Something")
+        self.assertEqual(response.data, "folder/none/Something.pdf")
 
         with override_settings(FILENAME_FORMAT_REMOVE_NONE=True):
             response = self.client.post(
@@ -399,7 +399,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
                 content_type="application/json",
             )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "folder/Something")
+        self.assertEqual(response.data, "folder/Something.pdf")
 
     def test_test_storage_path_requires_document_view_permission(self) -> None:
         owner = User.objects.create_user(username="owner")
@@ -447,7 +447,27 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "path/Shared")
+        self.assertEqual(response.data, "path/Shared.pdf")
+
+    def test_test_storage_path_prefers_existing_filename_extension(self) -> None:
+        document = Document.objects.create(
+            mime_type="image/jpeg",
+            filename="existing/Document.jpeg",
+            title="Something",
+            checksum="123",
+        )
+        response = self.client.post(
+            f"{self.ENDPOINT}test/",
+            json.dumps(
+                {
+                    "document": document.id,
+                    "path": "path/{{ title }}",
+                },
+            ),
+            content_type="application/json",
+        )
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data, "path/Something.jpeg")
 
     def test_test_storage_path_exposes_basic_document_context_but_not_sensitive_owner_data(
         self,
@@ -478,12 +498,12 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "owner")
+        self.assertEqual(response.data, "owner.pdf")
 
         for expression, expected in (
-            ("{{ document.content }}", "Top secret content"),
+            ("{{ document.content }}", "Top secret content.pdf"),
-            ("{{ document.id }}", str(document.id)),
+            ("{{ document.id }}", f"{document.id}.pdf"),
-            ("{{ document.page_count }}", "2"),
+            ("{{ document.page_count }}", "2.pdf"),
         ):
             response = self.client.post(
                 f"{self.ENDPOINT}test/",
@@ -545,7 +565,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "Private Correspondent")
+        self.assertEqual(response.data, "Private Correspondent.pdf")
 
         response = self.client.post(
             f"{self.ENDPOINT}test/",
@@ -560,7 +580,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "Private Correspondent")
+        self.assertEqual(response.data, "Private Correspondent.pdf")
 
     def test_test_storage_path_superuser_can_view_private_related_objects(self) -> None:
         owner = User.objects.create_user(username="owner")
@@ -589,7 +609,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "Private Correspondent")
+        self.assertEqual(response.data, "Private Correspondent.pdf")
 
     def test_test_storage_path_includes_doc_type_storage_path_and_tags(
         self,
@@ -636,7 +656,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "Private Type/private/path/Private Tag")
+        self.assertEqual(response.data, "Private Type/private/path/Private Tag.pdf")
 
         response = self.client.post(
             f"{self.ENDPOINT}test/",
@@ -649,7 +669,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "Private Type/Private Tag")
+        self.assertEqual(response.data, "Private Type/Private Tag.pdf")
 
     def test_test_storage_path_includes_custom_fields_for_visible_document(
         self,
@@ -685,7 +705,7 @@ class TestApiStoragePaths(DirectoriesMixin, APITestCase):
             content_type="application/json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(response.data, "42")
+        self.assertEqual(response.data, "42.pdf")
 
 
 class TestBulkEditObjects(APITestCase):

src/documents/views.py

@@ -3290,6 +3290,12 @@ class StoragePathViewSet(PermissionsAwareDocumentCountMixin, ModelViewSet):
         path = serializer.validated_data.get("path")
 
         result = format_filename(document, path)
+        if result:
+            extension = (
+                Path(str(document.filename)).suffix if document.filename else ""
+            ) or document.file_type
+            result_path = Path(result)
+            result = str(result_path.with_name(f"{result_path.name}{extension}"))
         return Response(result)
 
 

src/locale/en_US/LC_MESSAGES/django.po

@@ -2,7 +2,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: paperless-ngx\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2026-03-26 14:37+0000\n"
+"POT-Creation-Date: 2026-03-28 20:59+0000\n"
 "PO-Revision-Date: 2022-02-17 04:17\n"
 "Last-Translator: \n"
 "Language-Team: English\n"
@@ -1341,7 +1341,7 @@ msgstr ""
 msgid "Duplicate document identifiers are not allowed."
 msgstr ""
 
-#: documents/serialisers.py:2587 documents/views.py:3599
+#: documents/serialisers.py:2587 documents/views.py:3605
 #, python-format
 msgid "Documents not found: %(ids)s"
 msgstr ""
@@ -1613,20 +1613,20 @@ msgstr ""
 msgid "Invalid more_like_id"
 msgstr ""
 
-#: documents/views.py:3611
+#: documents/views.py:3617
 #, python-format
 msgid "Insufficient permissions to share document %(id)s."
 msgstr ""
 
-#: documents/views.py:3654
+#: documents/views.py:3660
 msgid "Bundle is already being processed."
 msgstr ""
 
-#: documents/views.py:3711
+#: documents/views.py:3717
 msgid "The share link bundle is still being prepared. Please try again later."
 msgstr ""
 
-#: documents/views.py:3721
+#: documents/views.py:3727
 msgid "The share link bundle is unavailable."
 msgstr ""
 

src/paperless/tests/settings/test_custom_parsers.py

@@ -79,6 +79,15 @@ class TestRedisSocketConversion:
                 ),
                 id="celery_style_socket_with_credentials",
             ),
+            # Empty username, password only: unix://:SECRET@/path.sock
+            pytest.param(
+                "unix://:SECRET@/run/redis/paperless.sock",
+                (
+                    "redis+socket://:SECRET@/run/redis/paperless.sock",
+                    "unix://:SECRET@/run/redis/paperless.sock",
+                ),
+                id="redis_py_style_socket_with_password_only",
+            ),
         ],
     )
     def test_redis_socket_parsing(