Ok, now move suffix into centralized generate_filename, use root doc for filenaming

docs/advanced_usage.md

@@ -262,6 +262,10 @@ your files differently, you can do that by adjusting the
 or using [storage paths (see below)](#storage-paths). Paperless adds the
 correct file extension e.g. `.pdf`, `.jpg` automatically.
 
+When a document has file versions, each version uses the same naming rules and
+storage path resolution as any other document file, with an added version suffix
+such as `_v1`, `_v2`, etc.
+
 This variable allows you to configure the filename (folders are allowed)
 using placeholders. For example, configuring this to
 
@@ -353,6 +357,8 @@ If paperless detects that two documents share the same filename,
 paperless will automatically append `_01`, `_02`, etc to the filename.
 This happens if all the placeholders in a filename evaluate to the same
 value.
+For versioned files, this counter is appended after the version suffix
+(for example `statement_v2_01.pdf`).
 
 If there are any errors in the placeholders included in `PAPERLESS_FILENAME_FORMAT`,
 paperless will fall back to using the default naming scheme instead.

docs/usage.md

@@ -95,6 +95,7 @@ Think of versions as **file history** for a document.
 
 -   Versions track the underlying file and extracted text content (OCR/text).
 -   Metadata such as tags, correspondent, document type, storage path and custom fields stay on the "root" document.
+-   Version files follow normal filename formatting (including storage paths) and add a `_vN` suffix (for example `_v1`, `_v2`).
 -   By default, search and document content use the latest version.
 -   In document detail, selecting a version switches the preview, file metadata and content (and download etc buttons) to that version.
 -   Deleting a non-root version keeps metadata and falls back to the latest remaining version.

src/documents/consumer.py

@@ -203,7 +203,6 @@ class ConsumerPlugin(
         version_doc.page_count = page_count
         version_doc.mime_type = mime_type
         version_doc.original_filename = self.filename
-        version_doc.storage_path = root_doc_frozen.storage_path
         # Clear unique file path fields so they can be generated uniquely later
         version_doc.filename = None
         version_doc.archive_filename = None

src/documents/file_handling.py

@@ -128,11 +128,18 @@ def generate_filename(
     counter=0,
     archive_filename=False,
 ) -> Path:
+    # version docs use the root document for formatting, just with a suffix
+    context_doc = doc if doc.root_document_id is None else doc.root_document
+    version_suffix = (
+        f"_v{doc.version_index}"
+        if doc.root_document_id is not None and doc.version_index is not None
+        else ""
+    )
     base_path: Path | None = None
 
     # Determine the source of the format string
-    if doc.storage_path is not None:
-        filename_format = doc.storage_path.path
+    if context_doc.storage_path is not None:
+        filename_format = context_doc.storage_path.path
     elif settings.FILENAME_FORMAT is not None:
         # Maybe convert old to new style
         filename_format = convert_format_str_to_template_format(
@@ -143,7 +150,7 @@ def generate_filename(
 
     # If we have one, render it
     if filename_format is not None:
-        rendered_path: str | None = format_filename(doc, filename_format)
+        rendered_path: str | None = format_filename(context_doc, filename_format)
         if rendered_path:
             base_path = Path(rendered_path)
 
@@ -157,7 +164,7 @@ def generate_filename(
         base_filename = base_path.name
 
         # Build the final filename with counter and filetype
-        final_filename = f"{base_filename}{counter_str}{filetype_str}"
+        final_filename = f"{base_filename}{version_suffix}{counter_str}{filetype_str}"
 
         # If we have a directory component, include it
         if str(directory) != ".":
@@ -166,7 +173,9 @@ def generate_filename(
             full_path = Path(final_filename)
     else:
         # No template, use document ID
-        final_filename = f"{doc.pk:07}{counter_str}{filetype_str}"
+        final_filename = (
+            f"{context_doc.pk:07}{version_suffix}{counter_str}{filetype_str}"
+        )
         full_path = Path(final_filename)
 
     return full_path

src/documents/signals/handlers.py

@@ -596,6 +596,16 @@ def update_filename_and_move_files(
                 root=settings.ARCHIVE_DIR,
             )
 
+    # Keep version files in sync with root
+    if instance.root_document_id is None:
+        for version_doc in Document.objects.filter(root_document_id=instance.pk).only(
+            "pk",
+        ):
+            update_filename_and_move_files(
+                Document,
+                version_doc,
+            )
+
 
 @shared_task
 def process_cf_select_update(custom_field: CustomField) -> None:

src/documents/tests/test_consumer.py

@@ -699,6 +699,13 @@ class TestConsumer(
         self.assertIsNotNone(root_doc)
         assert root_doc is not None
 
+        root_storage_path = StoragePath.objects.create(
+            name="version-root-path",
+            path="root/{{title}}",
+        )
+        root_doc.storage_path = root_storage_path
+        root_doc.save()
+
         actor = User.objects.create_user(
             username="actor",
             email="actor@example.com",
@@ -810,6 +817,63 @@ class TestConsumer(
         self.assertEqual(version.original_filename, "valid_pdf_version-upload")
         self.assertTrue(bool(version.content))
 
+    @override_settings(AUDIT_LOG_ENABLED=True)
+    @mock.patch("documents.consumer.load_classifier")
+    def test_consume_version_index_monotonic_after_version_deletion(self, m) -> None:
+        m.return_value = MagicMock()
+
+        with self.get_consumer(self.get_test_file()) as consumer:
+            consumer.run()
+
+        root_doc = Document.objects.first()
+        self.assertIsNotNone(root_doc)
+        assert root_doc is not None
+
+        def consume_version(version_file: Path) -> Document:
+            status = DummyProgressManager(version_file.name, None)
+            overrides = DocumentMetadataOverrides()
+            doc = ConsumableDocument(
+                DocumentSource.ApiUpload,
+                original_file=version_file,
+                root_document_id=root_doc.pk,
+            )
+            preflight = ConsumerPreflightPlugin(
+                doc,
+                overrides,
+                status,  # type: ignore[arg-type]
+                self.dirs.scratch_dir,
+                "task-id",
+            )
+            preflight.setup()
+            preflight.run()
+
+            consumer = ConsumerPlugin(
+                doc,
+                overrides,
+                status,  # type: ignore[arg-type]
+                self.dirs.scratch_dir,
+                "task-id",
+            )
+            consumer.setup()
+            try:
+                consumer.run()
+            finally:
+                consumer.cleanup()
+
+            version = (
+                Document.objects.filter(root_document=root_doc).order_by("-id").first()
+            )
+            assert version is not None
+            return version
+
+        v1 = consume_version(self.get_test_file2())
+        self.assertEqual(v1.version_index, 1)
+        v1.delete()
+
+        # The next version should have version_index 2, even though version_index 1 was deleted
+        v2 = consume_version(self.get_test_file())
+        self.assertEqual(v2.version_index, 2)
+
     @mock.patch("documents.consumer.load_classifier")
     def testClassifyDocument(self, m) -> None:
         correspondent = Correspondent.objects.create(

src/documents/tests/test_file_handling.py

@@ -77,6 +77,58 @@ class TestFileHandling(DirectoriesMixin, FileSystemAssertsMixin, TestCase):
             settings.ORIGINALS_DIR / "test" / "test.pdf",
         )
 
+    @override_settings(FILENAME_FORMAT=None)
+    def test_root_storage_path_change_updates_version_files(self) -> None:
+        old_storage_path = StoragePath.objects.create(
+            name="old-path",
+            path="old/{{title}}",
+        )
+        new_storage_path = StoragePath.objects.create(
+            name="new-path",
+            path="new/{{title}}",
+        )
+
+        root_doc = Document.objects.create(
+            title="rootdoc",
+            mime_type="application/pdf",
+            checksum="root-checksum",
+            storage_path=old_storage_path,
+        )
+        version_doc = Document.objects.create(
+            title="version-title",
+            mime_type="application/pdf",
+            checksum="version-checksum",
+            root_document=root_doc,
+            version_index=1,
+        )
+
+        Document.objects.filter(pk=root_doc.pk).update(
+            filename=generate_filename(root_doc),
+        )
+        Document.objects.filter(pk=version_doc.pk).update(
+            filename=generate_filename(version_doc),
+        )
+        root_doc.refresh_from_db()
+        version_doc.refresh_from_db()
+
+        create_source_path_directory(root_doc.source_path)
+        Path(root_doc.source_path).touch()
+        create_source_path_directory(version_doc.source_path)
+        Path(version_doc.source_path).touch()
+
+        root_doc.storage_path = new_storage_path
+        root_doc.save()
+
+        root_doc.refresh_from_db()
+        version_doc.refresh_from_db()
+
+        self.assertEqual(root_doc.filename, "new/rootdoc.pdf")
+        self.assertEqual(version_doc.filename, "new/rootdoc_v1.pdf")
+        self.assertIsFile(root_doc.source_path)
+        self.assertIsFile(version_doc.source_path)
+        self.assertIsNotFile(settings.ORIGINALS_DIR / "old" / "rootdoc.pdf")
+        self.assertIsNotFile(settings.ORIGINALS_DIR / "old" / "rootdoc_v1.pdf")
+
     @override_settings(FILENAME_FORMAT="{correspondent}/{correspondent}")
     def test_file_renaming_missing_permissions(self) -> None:
         document = Document()
@@ -1222,6 +1274,94 @@ class TestFilenameGeneration(DirectoriesMixin, TestCase):
             Path("logs.pdf"),
         )
 
+    @override_settings(FILENAME_FORMAT="{title}")
+    def test_version_index_suffix_for_template_filename(self) -> None:
+        root_doc = Document.objects.create(
+            title="the_doc",
+            mime_type="application/pdf",
+            checksum="root-checksum",
+        )
+        version_doc = Document.objects.create(
+            title="the_doc",
+            mime_type="application/pdf",
+            checksum="version-checksum",
+            root_document=root_doc,
+            version_index=1,
+        )
+
+        self.assertEqual(generate_filename(version_doc), Path("the_doc_v1.pdf"))
+        self.assertEqual(
+            generate_filename(version_doc, counter=1),
+            Path("the_doc_v1_01.pdf"),
+        )
+
+    @override_settings(FILENAME_FORMAT=None)
+    def test_version_index_suffix_for_default_filename(self) -> None:
+        root_doc = Document.objects.create(
+            title="root",
+            mime_type="text/plain",
+            checksum="root-checksum",
+        )
+        version_doc = Document.objects.create(
+            title="root",
+            mime_type="text/plain",
+            checksum="version-checksum",
+            root_document=root_doc,
+            version_index=2,
+        )
+
+        self.assertEqual(
+            generate_filename(version_doc),
+            Path(f"{root_doc.pk:07d}_v2.txt"),
+        )
+        self.assertEqual(
+            generate_filename(version_doc, archive_filename=True),
+            Path(f"{root_doc.pk:07d}_v2.pdf"),
+        )
+
+    @override_settings(FILENAME_FORMAT="{original_name}")
+    def test_version_index_suffix_with_original_name_placeholder(self) -> None:
+        root_doc = Document.objects.create(
+            title="root",
+            mime_type="application/pdf",
+            checksum="root-checksum",
+            original_filename="root-upload.pdf",
+        )
+        version_doc = Document.objects.create(
+            title="root",
+            mime_type="application/pdf",
+            checksum="version-checksum",
+            root_document=root_doc,
+            version_index=1,
+            original_filename="version-upload.pdf",
+        )
+
+        self.assertEqual(generate_filename(version_doc), Path("root-upload_v1.pdf"))
+
+    def test_version_index_suffix_with_storage_path(self) -> None:
+        storage_path = StoragePath.objects.create(
+            name="vtest",
+            path="folder/{{title}}",
+        )
+        root_doc = Document.objects.create(
+            title="storage_doc",
+            mime_type="application/pdf",
+            checksum="root-checksum",
+            storage_path=storage_path,
+        )
+        version_doc = Document.objects.create(
+            title="version_title_should_not_be_used",
+            mime_type="application/pdf",
+            checksum="version-checksum",
+            root_document=root_doc,
+            version_index=3,
+        )
+
+        self.assertEqual(
+            generate_filename(version_doc),
+            Path("folder/storage_doc_v3.pdf"),
+        )
+
     @override_settings(
         FILENAME_FORMAT="XX{correspondent}/{title}",
         FILENAME_FORMAT_REMOVE_NONE=True,