persistence directory migrations v4 for new deck configuration

robot-server/robot_server/persistence/_migrations/v3_to_v4.py

@@ -0,0 +1,24 @@
+"""Migrate the persistence directory from schema 3 to 4.
+
+Summary of changes from schema 3:
+
+- Deck Configuration now Supports the addition of Modules as Fixtures
+- Fixture items within the configuration have an optional Serial Number field
+- NOTE: Database has not changed, maintains form from v3 of SQLite schema
+- NOTE: Schema 3 is forward compatible with schema 4, so migration is a simple directory copy action
+
+"""
+
+from pathlib import Path
+import shutil
+from .._folder_migrator import Migration
+
+
+class Migration3To4(Migration):  # noqa: D101
+    def migrate(self, source_dir: Path, dest_dir: Path) -> None:
+        """Migrate the persistence directory from schema 3 to 4."""
+        for item in source_dir.iterdir():
+            if item.is_dir():
+                shutil.copytree(src=item, dst=dest_dir)
+            else:
+                shutil.copy(src=item, dst=dest_dir)

robot-server/robot_server/persistence/persistence_directory.py

@@ -11,7 +11,7 @@
 from anyio import Path as AsyncPath, to_thread
 
 from ._folder_migrator import MigrationOrchestrator
-from ._migrations import up_to_3
+from ._migrations import up_to_3, v3_to_v4
 
 
 _TEMP_PERSISTENCE_DIR_PREFIX: Final = "opentrons-robot-server-"
@@ -48,7 +48,10 @@ async def prepare_active_subdirectory(prepared_root: Path) -> Path:
     """Return the active persistence subdirectory after preparing it, if necessary."""
     migration_orchestrator = MigrationOrchestrator(
         root=prepared_root,
-        migrations=[up_to_3.MigrationUpTo3(subdirectory="3")],
+        migrations=[
+            up_to_3.MigrationUpTo3(subdirectory="3"),
+            v3_to_v4.Migration3To4(subdirectory="4"),
+        ],
         temp_file_prefix="temp-",
     )