Pre ping failing with uvloop

[chmeldax]

Describe the bug

When using aiomysql with uvloop==0.17.0, whenever MySQL closes a connection (due to wait_timeout), the subsequent pre-ping command fails with:

RuntimeError: unable to perform operation on <TCPTransport closed=True reading=False 0x62afa5bf29a0>; the handler is closed

This bug does not occur when uvloop is not used. Not sure whether to raise the issue with uvloop instead.

Might be related to #195?

To Reproduce

1. Use uvloop==0.17.0 and uvicorn==0.23.2.
2. Create a connection pool with pre_ping=True and pool_recycle not set.
3. Fire some queries.
4. Let MySQL close the connection due to the wait_timeout.
5. Send a HTTP request to the app and let the pre-ping request fail.

Expected behavior

The pre-ping request should succeed, and the HTTP request should succeed as well.

Logs/tracebacks

ERROR [root] Error: unable to perform operation on <TCPTransport closed=True reading=False 0x62afa5bd73a0>; the handler is closed
 ERROR [root] Stack: Traceback (most recent call last):
   File "/usr/local/lib/python3.11/site-packages/anyio/streams/memory.py", line 97, in receive
     return self.receive_nowait()
            ^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/anyio/streams/memory.py", line 92, in receive_nowait
     raise WouldBlock
 anyio.WouldBlock

 During handling of the above exception, another exception occurred:

 Traceback (most recent call last):
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py", line 78, in call_next
     message = await recv_stream.receive()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/anyio/streams/memory.py", line 112, in receive
     raise EndOfStream
 anyio.EndOfStream

 During handling of the above exception, another exception occurred:

 Traceback (most recent call last):
   File "/usr/local/lib/python3.11/site-packages/hisd_be4fe/api/errors.py", line 33, in catch_middleware_exceptions
     return await call_next(request)
            ^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py", line 84, in call_next
     raise app_exc
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py", line 70, in coro
     await self.app(scope, receive_or_disconnect, send_no_error)
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/cors.py", line 91, in __call__
     await self.simple_response(scope, receive, send, request_headers=headers)
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/cors.py", line 146, in simple_response
     await self.app(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/exceptions.py", line 79, in __call__
     raise exc
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/exceptions.py", line 68, in __call__
     await self.app(scope, receive, sender)
   File "/usr/local/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py", line 20, in __call__
     raise e
   File "/usr/local/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py", line 17, in __call__
     await self.app(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/routing.py", line 718, in __call__
     await route.handle(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/routing.py", line 276, in handle
     await self.app(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/routing.py", line 66, in app
     response = await func(request)
                ^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/fastapi/routing.py", line 231, in app
     solved_result = await solve_dependencies(
                     ^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/fastapi/dependencies/utils.py", line 622, in solve_dependencies
     solved = await call(**sub_values)
              ^^^^^^^^^^^^^^^^^^^^^^^^
   File "<makefun-gen-2>", line 2, in current_user_dependency
   File "/usr/local/lib/python3.11/site-packages/[redacted]/authentication/authenticator.py", line 143, in current_user_dependency
     user, _ = await self._authenticate(
               ^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/[redacted]/authentication/authenticator.py", line 184, in _authenticate
     user = await strategy.read_token(token, user_manager, authorized, ignore_expired)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/[redacted]/authentication/strategy/db/strategy.py", line 30, in read_token
     access_token = await self.access_token_db.get_by_token(token, max_age, authorized, ignore_expired)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/[redacted]/[redacted]/access_token.py", line 76, in get_by_token
     results = await self.session.execute(statement)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/ext/asyncio/session.py", line 439, in execute
     result = await greenlet_spawn(
              ^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 190, in greenlet_spawn
     result = context.throw(*sys.exc_info())
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 2246, in execute
     return self._execute_internal(
            ^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 2131, in _execute_internal
     conn = self._connection_for_bind(bind)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 1998, in _connection_for_bind
     return trans._connection_for_bind(engine, execution_options)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "<string>", line 2, in _connection_for_bind
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/state_changes.py", line 139, in _go
     ret_value = fn(self, *arg, **kw)
                 ^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 1123, in _connection_for_bind
     conn = bind.connect()
            ^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 3264, in connect
     return self._connection_cls(self)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 145, in __init__
     self._dbapi_connection = engine.raw_connection()
                              ^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 3288, in raw_connection
     return self.pool.connect()
            ^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/pool/base.py", line 452, in connect
     return _ConnectionFairy._checkout(self)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/pool/base.py", line 1366, in _checkout
     with util.safe_reraise():
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/langhelpers.py", line 147, in __exit__
     raise exc_value.with_traceback(exc_tb)
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/pool/base.py", line 1304, in _checkout
     result = pool._dialect._do_ping_w_event(
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/default.py", line 708, in _do_ping_w_event
     return self.do_ping(dbapi_connection)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/dialects/mysql/mysqldb.py", line 171, in do_ping
     dbapi_connection.ping(False)
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/dialects/mysql/aiomysql.py", line 191, in ping
     return self.await_(self._connection.ping(reconnect))
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 125, in await_only
     return current.driver.switch(awaitable)  # type: ignore[no-any-return]
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 185, in greenlet_spawn
     value = await result
             ^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/aiomysql/connection.py", line 493, in ping
     await self._execute_command(COMMAND.COM_PING, "")
   File "/usr/local/lib/python3.11/site-packages/aiomysql/connection.py", line 724, in _execute_command
     self._write_bytes(prelude + sql[:chunk_size - 1])
   File "/usr/local/lib/python3.11/site-packages/aiomysql/connection.py", line 669, in _write_bytes
     return self._writer.write(data)
            ^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/asyncio/streams.py", line 332, in write
     self._transport.write(data)
   File "uvloop/handles/stream.pyx", line 674, in uvloop.loop.UVStream.write
   File "uvloop/handles/handle.pyx", line 159, in uvloop.loop.UVHandle._ensure_alive
 RuntimeError: unable to perform operation on <TCPTransport closed=True reading=False 0x62afa5bd73a0>; the handler is closed

 ERROR [root] Method: GET
 ERROR [root] Url: [redacted]
 ERROR [root] req_time: 2023-09-11 13:46:49.891968
 ERROR [root] Error: unable to perform operation on <TCPTransport closed=True reading=False 0x62afa5bf29a0>; the handler is closed
 ERROR [root] Stack: Traceback (most recent call last):
   File "/usr/local/lib/python3.11/site-packages/anyio/streams/memory.py", line 97, in receive
     return self.receive_nowait()
            ^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/anyio/streams/memory.py", line 92, in receive_nowait
     raise WouldBlock
 anyio.WouldBlock

 During handling of the above exception, another exception occurred:

 Traceback (most recent call last):
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py", line 78, in call_next
     message = await recv_stream.receive()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/anyio/streams/memory.py", line 112, in receive
     raise EndOfStream
 anyio.EndOfStream

 During handling of the above exception, another exception occurred:

 Traceback (most recent call last):
   File "/usr/local/lib/python3.11/site-packages/hisd_be4fe/api/errors.py", line 33, in catch_middleware_exceptions
     return await call_next(request)
            ^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py", line 84, in call_next
     raise app_exc
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py", line 70, in coro
     await self.app(scope, receive_or_disconnect, send_no_error)
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/cors.py", line 91, in __call__
     await self.simple_response(scope, receive, send, request_headers=headers)
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/cors.py", line 146, in simple_response
     await self.app(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/exceptions.py", line 79, in __call__
     raise exc
   File "/usr/local/lib/python3.11/site-packages/starlette/middleware/exceptions.py", line 68, in __call__
     await self.app(scope, receive, sender)
   File "/usr/local/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py", line 20, in __call__
     raise e
   File "/usr/local/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py", line 17, in __call__
     await self.app(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/routing.py", line 718, in __call__
     await route.handle(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/routing.py", line 276, in handle
     await self.app(scope, receive, send)
   File "/usr/local/lib/python3.11/site-packages/starlette/routing.py", line 66, in app
     response = await func(request)
                ^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/fastapi/routing.py", line 231, in app
     solved_result = await solve_dependencies(
                     ^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/fastapi/dependencies/utils.py", line 622, in solve_dependencies
     solved = await call(**sub_values)
              ^^^^^^^^^^^^^^^^^^^^^^^^
   File "<makefun-gen-2>", line 2, in current_user_dependency
   File "/usr/local/lib/python3.11/site-packages/[redacted]/authentication/authenticator.py", line 143, in current_user_dependency
     user, _ = await self._authenticate(
               ^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/[redacted]/authentication/authenticator.py", line 184, in _authenticate
     user = await strategy.read_token(token, user_manager, authorized, ignore_expired)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/[redacted]/authentication/strategy/db/strategy.py", line 30, in read_token
     access_token = await self.access_token_db.get_by_token(token, max_age, authorized, ignore_expired)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/[redacted]/filuta_uds/access_token.py", line 76, in get_by_token
     results = await self.session.execute(statement)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/ext/asyncio/session.py", line 439, in execute
     result = await greenlet_spawn(
              ^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 190, in greenlet_spawn
     result = context.throw(*sys.exc_info())
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 2246, in execute
     return self._execute_internal(
            ^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 2131, in _execute_internal
     conn = self._connection_for_bind(bind)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 1998, in _connection_for_bind
     return trans._connection_for_bind(engine, execution_options)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "<string>", line 2, in _connection_for_bind
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/state_changes.py", line 139, in _go
     ret_value = fn(self, *arg, **kw)
                 ^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/orm/session.py", line 1123, in _connection_for_bind
     conn = bind.connect()
            ^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 3264, in connect
     return self._connection_cls(self)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 145, in __init__
     self._dbapi_connection = engine.raw_connection()
                              ^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 3288, in raw_connection
     return self.pool.connect()
            ^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/pool/base.py", line 452, in connect
     return _ConnectionFairy._checkout(self)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/pool/base.py", line 1366, in _checkout
     with util.safe_reraise():
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/langhelpers.py", line 147, in __exit__
     raise exc_value.with_traceback(exc_tb)
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/pool/base.py", line 1304, in _checkout
     result = pool._dialect._do_ping_w_event(
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/default.py", line 708, in _do_ping_w_event
     return self.do_ping(dbapi_connection)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/dialects/mysql/mysqldb.py", line 171, in do_ping
     dbapi_connection.ping(False)
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/dialects/mysql/aiomysql.py", line 191, in ping
     return self.await_(self._connection.ping(reconnect))
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 125, in await_only
     return current.driver.switch(awaitable)  # type: ignore[no-any-return]
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 185, in greenlet_spawn
     value = await result
             ^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/site-packages/aiomysql/connection.py", line 493, in ping
     await self._execute_command(COMMAND.COM_PING, "")
   File "/usr/local/lib/python3.11/site-packages/aiomysql/connection.py", line 724, in _execute_command
     self._write_bytes(prelude + sql[:chunk_size - 1])
   File "/usr/local/lib/python3.11/site-packages/aiomysql/connection.py", line 669, in _write_bytes
     return self._writer.write(data)
            ^^^^^^^^^^^^^^^^^^^^^^^^
   File "/usr/local/lib/python3.11/asyncio/streams.py", line 332, in write
     self._transport.write(data)
   File "uvloop/handles/stream.pyx", line 674, in uvloop.loop.UVStream.write
   File "uvloop/handles/handle.pyx", line 159, in uvloop.loop.UVHandle._ensure_alive
 RuntimeError: unable to perform operation on <TCPTransport closed=True reading=False 0x62afa5bf29a0>; the handler is closed

Python Version

3.11.4

aiomysql Version

0.2.0

PyMySQL Version

1.0.3

SQLAlchemy Version

2.0.19

OS

Ubuntu 20.04.4 LTS

Database type and version

8.0.15

Additional context

No response

Code of Conduct

• I agree to follow the aio-libs Code of Conduct

[northmorn]

same issue, in my case, pool_recycle=3600, mysql wait_timeout is 28800

Logs/tracebacks

  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/ext/asyncio/session.py", line 461, in execute
    result = await greenlet_spawn(
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 201, in greenlet_spawn
    result = context.throw(*sys.exc_info())
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/session.py", line 2351, in execute
    return self._execute_internal(
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/session.py", line 2226, in _execute_internal
    conn = self._connection_for_bind(bind)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/session.py", line 2095, in _connection_for_bind
    return trans._connection_for_bind(engine, execution_options)
  File "<string>", line 2, in _connection_for_bind
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/state_changes.py", line 139, in _go
    ret_value = fn(self, *arg, **kw)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/session.py", line 1189, in _connection_for_bind
    conn = bind.connect()
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 3276, in connect
    return self._connection_cls(self)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 146, in __init__
    self._dbapi_connection = engine.raw_connection()
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 3300, in raw_connection
    return self.pool.connect()
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/pool/base.py", line 449, in connect
    return _ConnectionFairy._checkout(self)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/pool/base.py", line 1362, in _checkout
    with util.safe_reraise():
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/util/langhelpers.py", line 146, in __exit__
    raise exc_value.with_traceback(exc_tb)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/pool/base.py", line 1300, in _checkout
    result = pool._dialect._do_ping_w_event(
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/default.py", line 715, in _do_ping_w_event
    return self.do_ping(dbapi_connection)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/dialects/mysql/pymysql.py", line 107, in do_ping
    dbapi_connection.ping(False)
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/dialects/mysql/aiomysql.py", line 185, in ping
    return self.await_(self._connection.ping(reconnect))
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 131, in await_only
    return current.driver.switch(awaitable)  # type: ignore[no-any-return]
  File "/usr/local/lib/python3.10/site-packages/sqlalchemy/util/_concurrency_py3k.py", line 196, in greenlet_spawn
    value = await result
  File "/usr/local/lib/python3.10/site-packages/aiomysql/connection.py", line 493, in ping
    await self._execute_command(COMMAND.COM_PING, "")
  File "/usr/local/lib/python3.10/site-packages/aiomysql/connection.py", line 724, in _execute_command
    self._write_bytes(prelude + sql[:chunk_size - 1])
  File "/usr/local/lib/python3.10/site-packages/aiomysql/connection.py", line 669, in _write_bytes
    return self._writer.write(data)
  File "/usr/local/lib/python3.10/asyncio/streams.py", line 325, in write
    self._transport.write(data)
  File "uvloop/handles/stream.pyx", line 674, in uvloop.loop.UVStream.write
  File "uvloop/handles/handle.pyx", line 159, in uvloop.loop.UVHandle._ensure_alive
RuntimeError: unable to perform operation on <TCPTransport closed=True reading=False 0x55a968d3bf20>; the handler is closed

SQLAlchemy
Version: 2.0.30
PyMySQL
Version: 1.1.0
aiomysql
Version: 0.2.0
uvloop
Version: 0.19.0
mariadb
10.3.5
Debian GNU/Linux 11 (bullseye)

and here is a related pr
https://github.com/aio-libs/aiomysql/pull/982/files

        try:
            return self._writer.write(data)
        except RuntimeError as e:
            self.close()

[YaoJusheng]

Same issue +1, is there any fix for it now?

Version List:

SQLAlchemy: 2.0.32
PyMySQL:    1.1.1
aiomysql:   0.2.0
uvicorn:    0.30.6
uvloop:     0.20.0
asyncio:    3.4.3

The version of MySQL is 8.0.39.

[andrmueller]

Can be fixed by not using uvloop but vanilla asyncio instead:

In case one of your used packages depends on uvloop (which was the case for me) just add

asyncio.set_event_loop_policy(asyncio.DefaultEventLoopPolicy())

before any async operation is started.
For python3.12+ the speed difference seems to be marginal, can't tell for lower python versions.

An MRE has also been shared recently in case you want to reproduce the issue.