refactor

app/database.py

@@ -0,0 +1,37 @@
+from typing import AsyncGenerator
+
+from fastapi import HTTPException
+from sqlalchemy.exc import SQLAlchemyError
+from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
+from sqlalchemy.orm import sessionmaker
+
+from app import config
+
+global_settings = config.get_settings()
+url = global_settings.asyncpg_url
+
+engine = create_async_engine(
+    url,
+    future=True,
+    echo=True,
+)
+
+# expire_on_commit=False will prevent attributes from being expired
+# after commit.
+async_session = sessionmaker(engine, expire_on_commit=False, class_=AsyncSession)
+
+
+# Dependency
+async def get_db() -> AsyncGenerator:
+    async with async_session() as session:
+        try:
+            yield session
+            await session.commit()
+        except SQLAlchemyError as sql_ex:
+            await session.rollback()
+            raise sql_ex
+        except HTTPException as http_ex:
+            await session.rollback()
+            raise http_ex
+        finally:
+            await session.close()