Invoke the given synchronous (i.e. not async) callable, passing a synchronous-style :class:`_orm.Session` as the first argument. This method allows traditional synchronous SQLAlchemy functions to run within the context of an asyncio application. E.g.::
(
self,
fn: Callable[Concatenate[Session, _P], _T],
*arg: _P.args,
**kw: _P.kwargs,
)
| 333 | ) |
| 334 | |
| 335 | async def run_sync( |
| 336 | self, |
| 337 | fn: Callable[Concatenate[Session, _P], _T], |
| 338 | *arg: _P.args, |
| 339 | **kw: _P.kwargs, |
| 340 | ) -> _T: |
| 341 | '''Invoke the given synchronous (i.e. not async) callable, |
| 342 | passing a synchronous-style :class:`_orm.Session` as the first |
| 343 | argument. |
| 344 | |
| 345 | This method allows traditional synchronous SQLAlchemy functions to |
| 346 | run within the context of an asyncio application. |
| 347 | |
| 348 | E.g.:: |
| 349 | |
| 350 | def some_business_method(session: Session, param: str) -> str: |
| 351 | """A synchronous function that does not require awaiting |
| 352 | |
| 353 | :param session: a SQLAlchemy Session, used synchronously |
| 354 | |
| 355 | :return: an optional return value is supported |
| 356 | |
| 357 | """ |
| 358 | session.add(MyObject(param=param)) |
| 359 | session.flush() |
| 360 | return "success" |
| 361 | |
| 362 | |
| 363 | async def do_something_async(async_engine: AsyncEngine) -> None: |
| 364 | """an async function that uses awaiting""" |
| 365 | |
| 366 | with AsyncSession(async_engine) as async_session: |
| 367 | # run some_business_method() with a sync-style |
| 368 | # Session, proxied into an awaitable |
| 369 | return_code = await async_session.run_sync( |
| 370 | some_business_method, param="param1" |
| 371 | ) |
| 372 | print(return_code) |
| 373 | |
| 374 | This method maintains the asyncio event loop all the way through |
| 375 | to the database connection by running the given callable in a |
| 376 | specially instrumented greenlet. |
| 377 | |
| 378 | .. tip:: |
| 379 | |
| 380 | The provided callable is invoked inline within the asyncio event |
| 381 | loop, and will block on traditional IO calls. IO within this |
| 382 | callable should only call into SQLAlchemy's asyncio database |
| 383 | APIs which will be properly adapted to the greenlet context. |
| 384 | |
| 385 | .. seealso:: |
| 386 | |
| 387 | :class:`.AsyncAttrs` - a mixin for ORM mapped classes that provides |
| 388 | a similar feature more succinctly on a per-attribute basis |
| 389 | |
| 390 | :meth:`.AsyncConnection.run_sync` |
| 391 | |
| 392 | :ref:`session_run_sync` |