WIP checkpoint: Scaffold FastAPI backend project structure

backend/app/models/session.py

@@ -1,4 +1,6 @@
-from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Boolean
+import uuid
+
+from sqlalchemy import Column, String, DateTime, ForeignKey, Boolean
 from sqlalchemy.orm import relationship
 from sqlalchemy.sql import func
 from app.database import Base
@@ -7,7 +9,7 @@ from app.database import Base
 class Session(Base):
     __tablename__ = "sessions"
 
-    id = Column(String, primary_key=True)
+    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
     user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
     token = Column(String, unique=True, index=True, nullable=False)
     expires_at = Column(DateTime(timezone=True), nullable=False)

backend/app/models/world.py

@@ -1,4 +1,5 @@
-from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey, Enum
+from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey
+from sqlalchemy.dialects.postgresql import ENUM
 from sqlalchemy.orm import relationship
 from sqlalchemy.sql import func
 import enum
@@ -19,7 +20,10 @@ class World(Base):
     name = Column(String(255), nullable=False)
     description = Column(Text, nullable=True)
     owner_id = Column(Integer, ForeignKey("users.id"), nullable=False)
-    visibility = Column(Enum(WorldVisibility), default=WorldVisibility.PUBLIC)
+    visibility = Column(
+        ENUM(WorldVisibility, name="world_visibility", create_type=False),
+        default=WorldVisibility.PUBLIC,
+    )
     created_at = Column(DateTime(timezone=True), server_default=func.now())
     updated_at = Column(DateTime(timezone=True), onupdate=func.now())