Skip to content

[ServiceBus] Fix async sender AttributeError race in _open (#35618) #46683

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
SAY-5 wants to merge 2 commits into
base: main
Choose a base branch
from
+35 −19
Open

[ServiceBus] Fix async sender AttributeError race in _open (#35618) #46683

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
78fb508
fix(servicebus): guard async sender against handler race in _open
May 2, 2026
f568e44
address review: serialize _open() with asyncio.Lock
SAY-5 May 3, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions sdk/servicebus/azure-servicebus/CHANGELOG.md
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,5 +1,11 @@
# Release History

## 7.14.4 (Unreleased)

### Bugs Fixed

- Fixed a race condition in the async ServiceBusSender where concurrent coroutines could trigger `AttributeError: 'NoneType' object has no attribute 'client_ready_async'` when reusing a sender. ([#35618](https://github.com/Azure/azure-sdk-for-python/issues/35618))

## 7.14.3 (2025-11-11)

### Bugs Fixed
Expand Down
9 changes: 6 additions & 3 deletions sdk/servicebus/azure-servicebus/azure/servicebus/aio/_servicebus_sender_async.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -207,13 +207,16 @@ async def _open(self):
await self._handler.close_async()
auth = None if self._connection else (await create_authentication(self))
self._create_handler(auth)
# Capture a local reference to the handler to guard against concurrent
# coroutines mutating self._handler across awaits (see issue #35618).
handler = self._handler
try:
await self._handler.open_async(connection=self._connection)
while not await self._handler.client_ready_async():
await handler.open_async(connection=self._connection)
while not await handler.client_ready_async():
await asyncio.sleep(0.05)
self._running = True
self._max_message_size_on_link = (
self._amqp_transport.get_remote_max_message_size(self._handler) or MAX_MESSAGE_LENGTH_BYTES
self._amqp_transport.get_remote_max_message_size(handler) or MAX_MESSAGE_LENGTH_BYTES
)
if self._max_message_size_on_link >= MAX_BATCH_SIZE_PREMIUM:
self._max_batch_size_on_link = MAX_BATCH_SIZE_PREMIUM
Expand Down
Loading