SQLAlchemy 1.4 异步事件监听器

Question

尝试使用事件监听器(https://docs.sqlalchemy.org/en/14/core/events.html#sqlalchemy.events.ConnectionEvents) 在异步 sqlalchemy 引擎上并收到此错误:{NotImplementedError}此时未实现异步事件。将同步监听器应用于 AsyncEngine.sync_engine 或 AsyncConnection.sync_connection 属性。

如果我理解正确，我不能在异步引擎上使用事件，如果我想要事件支持，我必须切换到同步引擎？

engine: Engine = create_async_engine(
    URL, echo=True, future=True
)

async_session = sessionmaker(
    engine, class_=AsyncSession, expire_on_commit=False, future=True
)


event.listens_for(engine, "do_connect")(do_connect_listener)
event.listens_for(engine, "engine_connect")(engine_connect_listener)

Answer 1

从 github 上的 SQLAlchemy 讨论部分得到了答案。所有功劳都归功于 OP(https://github.com/sqlalchemy/sqlalchemy/discussions/6594#discussioncomment-836437):

“你好，

根据异常的建议，您可以在应用事件时使用 sync_engine/sync_connection。这是一个例子:"

import asyncio
from sqlalchemy import event
from sqlalchemy.ext.asyncio import create_async_engine

engine = create_async_engine("sqlite+aiosqlite:///:memory:")

@event.listens_for(engine.sync_engine, "do_connect")
def do_connect(dialect, conn_rec, cargs, cparams):
    print("some-function")

@event.listens_for(engine.sync_engine, "engine_connect")
def engine_connect(conn, branch):
    print("engine_connect", conn.exec_driver_sql("select 1").scalar())

async def go():
    async with engine.connect() as conn:
        res = await conn.exec_driver_sql("select 2")
        print("go", res.scalar())

asyncio.run(go())