Asynchronous sqlalchemy with explicit engine passed as parameter

database.py

from contextlib import asynccontextmanager
from enum import Enum

from sqlalchemy import (
    Column,
    Integer,
    String,
)
from sqlalchemy.ext.asyncio import create_async_engine, async_sessionmaker, AsyncEngine
from sqlalchemy.orm import declarative_base


class Engines(Enum):
    PRIMARY = create_async_engine(
        url="<your_connection_string>",
        echo=True,
    )
    SECONDARY = create_async_engine(
        url="<your_connection_string>",
        echo=True,
    )


Base = declarative_base()


class Tutorial(Base):
    __tablename__ = "tutorials"

    tutorial_id = Column(Integer, primary_key=True)
    name = Column(String(255), nullable=False)


def async_session_generator(engine: AsyncEngine):
    return async_sessionmaker(bind=engine)


@asynccontextmanager
async def get_session(engine: Engines = Engines.PRIMARY):
    try:
        async_session = async_session_generator(engine=engine.value)

        async with async_session() as session:
            yield session
    except:
        await session.rollback()
        raise
    finally:
        await session.close()