with some tests

backend/database.py

@@ -0,0 +1,18 @@
+import os
+from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
+from sqlalchemy.orm import DeclarativeBase
+
+DATABASE_URL = os.getenv("DATABASE_URL", "postgresql+asyncpg://postgres:postgres@localhost:5432/arbret")
+
+engine = create_async_engine(DATABASE_URL)
+async_session = async_sessionmaker(engine, expire_on_commit=False)
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+async def get_db():
+    async with async_session() as session:
+        yield session
+