✨ Create Makeable class

royalnet/alchemist/__init__.py

@@ -1,3 +1,4 @@
 from .func import *
+from .make import *
 from .repr import *
 from .update import *

royalnet/alchemist/make.py

@@ -0,0 +1,38 @@
+from royalnet.typing import *
+import sqlalchemy.orm as o
+
+
+T = TypeVar('T')
+
+
+class Makeable:
+    """
+    A mixin that can be added to a declared class to add the make and unmake methods, that try find an item with
+    specific properties and either create it if it doesn't exist or delete it if it exists.
+    """
+
+    @classmethod
+    def make(cls: Type[T], session: o.session.Session, **kwargs) -> T:
+        """Find the item with the specified name, or create it if it doesn't exist."""
+        # Find the item
+        item = session.query(cls).filter_by(**kwargs).one_or_none()
+        # Create the item
+        if item is None:
+            item = cls(**kwargs)
+            session.add(item)
+        # Return the item
+        return item
+
+    @classmethod
+    def unmake(cls: Type[T], session: o.session.Session, **kwargs) -> None:
+        """Find the item with the specified name, and delete it if it exists."""
+        # Find the item
+        item = session.query(cls).filter_by(**kwargs).one_or_none()
+        # Delete the item
+        if item is not None:
+            session.delete(item)
+
+
+__all__ = (
+    "Makeable",
+)