PipelineTask: check if pipeline has already been cancelled

CHANGELOG.md

@@ -89,6 +89,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- Check if `PipelineTask` has already been cancelled.
+
 - Don't raise an exception if event handler is not registered.
 
 - Upgraded `deepgram-sdk` to 4.1.0.

src/pipecat/pipeline/task.py

@@ -236,6 +236,7 @@ class PipelineTask(BaseTask):
             )
             observers.append(self._turn_trace_observer)
         self._finished = False
+        self._cancelled = False
 
         # This queue receives frames coming from the pipeline upstream.
         self._up_queue = asyncio.Queue()
@@ -346,7 +347,6 @@ class PipelineTask(BaseTask):
 
     async def cancel(self):
         """Stops the running pipeline immediately."""
-        logger.debug(f"Canceling pipeline task {self}")
         await self._cancel()
 
     async def run(self):
@@ -406,6 +406,9 @@ class PipelineTask(BaseTask):
                 await self.queue_frame(frame)
 
     async def _cancel(self):
+        if not self._cancelled:
+            logger.debug(f"Canceling pipeline task {self}")
+            self._cancelled = True
             # Make sure everything is cleaned up downstream. This is sent
             # out-of-band from the main streaming task which is what we want since
             # we want to cancel right away.