feat(FN-004): merge fusion/fn-004

apps/api/app/db.py

@@ -0,0 +1,25 @@
+from collections.abc import AsyncGenerator
+
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+
+from app.config import settings
+
+# Rewrite sync postgres URL to asyncpg
+DATABASE_URL = settings.database_url
+if DATABASE_URL.startswith("postgresql://"):
+    DATABASE_URL = DATABASE_URL.replace("postgresql://", "postgresql+asyncpg://", 1)
+
+engine = create_async_engine(DATABASE_URL, echo=settings.debug)
+AsyncSessionLocal = async_sessionmaker(
+    engine,
+    class_=AsyncSession,
+    expire_on_commit=False,
+)
+
+
+async def get_db_session() -> AsyncGenerator[AsyncSession, None]:
+    async with AsyncSessionLocal() as session:
+        try:
+            yield session
+        finally:
+            await session.close()