Expose prefer_filename_for_name on manual archive upload endpoint

POST /api/v1/archives/upload now accepts an optional
prefer_filename_for_name query param, forwarded to
ArchiveService.archive_print. Same flag already used by the FTP
pending-uploads review flow and virtual-printer dispatch (#1152);
this endpoint just didn't expose it. Default False, no behavior
change for existing callers.

Fixes #2609

backend/app/api/routes/archives.py

@@ -3312,10 +3312,18 @@ async def get_plate_preview(
 async def upload_archive(
     file: UploadFile = File(...),
     printer_id: int | None = None,
+    prefer_filename_for_name: bool = False,
     db: AsyncSession = Depends(get_db),
     current_user: User | None = RequirePermissionIfAuthEnabled(Permission.ARCHIVES_CREATE),
 ):
-    """Manually upload a 3MF file to archive."""
+    """Manually upload a 3MF file to archive.
+
+    prefer_filename_for_name: When True, use the uploaded filename stem as the
+    archive's display name even if the 3MF embeds a `print_name` in its
+    metadata. Same flag already used by the FTP review flow and virtual-printer
+    dispatch (see ArchiveService.archive_print) — this endpoint just didn't
+    expose it (#1152 follow-up).
+    """
     if not file.filename or not file.filename.endswith(".3mf"):
         raise HTTPException(400, "File must be a .3mf file")
 
@@ -3341,6 +3349,7 @@ async def upload_archive(
             printer_id=printer_id,
             source_file=temp_path,
             created_by_id=current_user.id if current_user else None,
+            prefer_filename_for_name=prefer_filename_for_name,
         )
 
         if not archive:

backend/tests/integration/test_archives_api.py

@@ -4,6 +4,7 @@ Tests the full request/response cycle for /api/v1/archives/ endpoints.
 """
 
 from pathlib import Path
+from unittest.mock import AsyncMock, patch
 
 import pytest
 from httpx import AsyncClient
@@ -12,6 +13,69 @@ from httpx import AsyncClient
 class TestArchivesAPI:
     """Integration tests for /api/v1/archives/ endpoints."""
 
+    # ========================================================================
+    # Upload endpoint
+    # ========================================================================
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    @pytest.mark.parametrize("prefer_filename_for_name", [True, False])
+    async def test_upload_archive_forwards_prefer_filename_for_name(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session, prefer_filename_for_name
+    ):
+        """POST /archives/upload must forward prefer_filename_for_name to
+        ArchiveService.archive_print unchanged — this flag lets a caller (e.g.
+        the manual upload UI or an external integration) ask for the uploaded
+        filename to win over the 3MF's embedded print_name (#1152 follow-up:
+        the flag existed on the service but wasn't exposed on this route).
+
+        archive_print is mocked (real 3MF metadata extraction isn't under test
+        here) but its return value is a real PrintArchive row from the
+        factory, so ArchiveResponse.model_validate in the route still exercises
+        real serialization instead of masking a broken response behind a bare
+        MagicMock.
+        """
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id, print_name="Mocked Return Archive")
+        archive_print_mock = AsyncMock(return_value=archive)
+
+        files = {"file": ("My Print (final).gcode.3mf", b"PK\x03\x04fake3mf", "application/octet-stream")}
+        params = {"prefer_filename_for_name": prefer_filename_for_name}
+
+        with patch(
+            "backend.app.api.routes.archives.ArchiveService.archive_print",
+            archive_print_mock,
+        ):
+            response = await async_client.post("/api/v1/archives/upload", files=files, params=params)
+
+        assert response.status_code == 200
+        assert archive_print_mock.await_count == 1
+        kwargs = archive_print_mock.await_args.kwargs
+        assert kwargs.get("prefer_filename_for_name") is prefer_filename_for_name
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_upload_archive_defaults_prefer_filename_for_name_false(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Omitting the query param must not change existing behavior for
+        callers that predate this flag."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id, print_name="Mocked Return Archive")
+        archive_print_mock = AsyncMock(return_value=archive)
+
+        files = {"file": ("existing-caller.gcode.3mf", b"PK\x03\x04fake3mf", "application/octet-stream")}
+
+        with patch(
+            "backend.app.api.routes.archives.ArchiveService.archive_print",
+            archive_print_mock,
+        ):
+            response = await async_client.post("/api/v1/archives/upload", files=files)
+
+        assert response.status_code == 200
+        kwargs = archive_print_mock.await_args.kwargs
+        assert kwargs.get("prefer_filename_for_name") is False
+
     # ========================================================================
     # List endpoints
     # ========================================================================