Merge pull request #4440 from pipecat-ai/filipi/daily_send_message_issue

Fixing a race condition when cleaning up the daily transport.

changelog/4440.fixed.md

@@ -0,0 +1 @@
+- Fixed a race condition in the Daily transport that caused `AttributeError: 'NoneType' object has no attribute 'send_app_message'` when tearing down a pipeline. Both `DailyInputTransport` and `DailyOutputTransport` share the same `DailyTransportClient` and both call `cleanup()`, which was releasing the underlying `CallClient` on the first call — leaving the second caller with a `None` client.

src/pipecat/transports/daily/transport.py

@@ -526,6 +526,7 @@ class DailyTransportClient(EventHandler):
         self._joined = False
         self._joined_event = asyncio.Event()
         self._leave_counter = 0
+        self._cleanup_counter = 0
 
         self._task_manager: BaseTaskManager | None = None
 
@@ -741,6 +742,7 @@ class DailyTransportClient(EventHandler):
         Args:
             setup: The frame processor setup configuration.
         """
+        self._cleanup_counter += 1
         if self._task_manager:
             return
 
@@ -754,6 +756,12 @@ class DailyTransportClient(EventHandler):
 
     async def cleanup(self):
         """Cleanup client resources and cancel tasks."""
+        # Decrement cleanup counter. DailyInputTransport and DailyOutputTransport
+        # share this client and both call cleanup(), so only run on the last call.
+        self._cleanup_counter -= 1
+        if self._cleanup_counter > 0:
+            return
+
         if self._event_task and self._task_manager:
             await self._task_manager.cancel_task(self._event_task)
             self._event_task = None