Improve Async TTS interruption handling by using AudioContextTTSService class and add changelog fragments

CHANGELOG.md

@@ -6,15 +6,6 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 <!-- towncrier release notes start -->
-## [Unreleased]
-
-### Changed
-
-- Enhanced interruption handling in `AsyncAITTSService` by supporting multi-context WebSocket sessions for more robust context management.
-
-### Fixed
-
-- Corrected TTFB metric calculation in `AsyncAIHttpTTSService`.
 
 ## [0.0.99] - 2026-01-13
 

changelog/3287.changed.md

@@ -0,0 +1 @@
+- Enhanced interruption handling in `AsyncAITTSService` by supporting multi-context WebSocket sessions for more robust context management.

changelog/3287.fixed.md

@@ -0,0 +1 @@
+- Corrected TTFB metric calculation in `AsyncAIHttpTTSService`.

src/pipecat/services/asyncai/tts.py

@@ -28,7 +28,7 @@ from pipecat.frames.frames import (
     TTSStoppedFrame,
 )
 from pipecat.processors.frame_processor import FrameDirection
-from pipecat.services.tts_service import WebsocketTTSService, TTSService
+from pipecat.services.tts_service import AudioContextTTSService, WebsocketTTSService, TTSService
 from pipecat.transcriptions.language import Language, resolve_language
 from pipecat.utils.tracing.service_decorators import traced_tts
 
@@ -73,7 +73,7 @@ def language_to_async_language(language: Language) -> Optional[str]:
     return resolve_language(language, LANGUAGE_MAP, use_base_code=True)
 
 
-class AsyncAITTSService(WebsocketTTSService):
+class AsyncAITTSService(AudioContextTTSService, WebsocketTTSService):
     """Async TTS service with WebSocket streaming.
 
     Provides text-to-speech using Async's streaming WebSocket API.
@@ -154,55 +154,6 @@ class AsyncAITTSService(WebsocketTTSService):
         self._keepalive_task = None
         self._started = False
     
-    async def create_audio_context(self, context_id: str):
-        """Create a new audio context for grouping related audio.
-
-        Args:
-            context_id: Unique identifier for the audio context.
-        """
-        await self._contexts_queue.put(context_id)
-        self._contexts[context_id] = asyncio.Queue()
-        logger.trace(f"{self} created audio context {context_id}")
-
-    async def append_to_audio_context(self, context_id: str, frame: TTSAudioRawFrame):
-        """Append audio to an existing context.
-
-        Args:
-            context_id: The context to append audio to.
-            frame: The audio frame to append.
-        """
-        if self.audio_context_available(context_id):
-            logger.trace(f"{self} appending audio {frame} to audio context {context_id}")
-            await self._contexts[context_id].put(frame)
-        else:
-            logger.warning(f"{self} unable to append audio to context {context_id}")
-
-    async def remove_audio_context(self, context_id: str):
-        """Remove an existing audio context.
-
-        Args:
-            context_id: The context to remove.
-        """
-        if self.audio_context_available(context_id):
-            # We just mark the audio context for deletion by appending
-            # None. Once we reach None while handling audio we know we can
-            # safely remove the context.
-            logger.trace(f"{self} marking audio context {context_id} for deletion")
-            await self._contexts[context_id].put(None)
-        else:
-            logger.warning(f"{self} unable to remove context {context_id}")
-
-    def audio_context_available(self, context_id: str) -> bool:
-        """Check whether the given audio context is registered.
-
-        Args:
-            context_id: The context ID to check.
-
-        Returns:
-            True if the context exists and is available.
-        """
-        return context_id in self._contexts
-    
     async def start(self, frame: StartFrame):
         """Start the Async TTS service.
 
@@ -210,7 +161,6 @@ class AsyncAITTSService(WebsocketTTSService):
             frame: The start frame containing initialization parameters.
         """
         await super().start(frame)
-        self._create_audio_context_task()
         self._settings["output_format"]["sample_rate"] = self.sample_rate
         await self._connect()
 
@@ -221,12 +171,6 @@ class AsyncAITTSService(WebsocketTTSService):
             frame: The end frame.
         """
         await super().stop(frame)
-        if self._audio_context_task:
-            # Indicate no more audio contexts are available. this will end the
-            # task cleanly after all contexts have been processed.
-            await self._contexts_queue.put(None)
-            await self._audio_context_task
-            self._audio_context_task = None
         await self._disconnect()
 
     async def cancel(self, frame: CancelFrame):
@@ -236,65 +180,7 @@ class AsyncAITTSService(WebsocketTTSService):
             frame: The cancel frame.
         """
         await super().cancel(frame)
-        await self._stop_audio_context_task()
-        await self._disconnect()        
-
-    async def _handle_interruption(self, frame: InterruptionFrame, direction: FrameDirection):
-        await super()._handle_interruption(frame, direction)
-        await self._stop_audio_context_task()
-        self._create_audio_context_task()
-
-    def _create_audio_context_task(self):
-        if not self._audio_context_task:
-            self._contexts_queue = asyncio.Queue()
-            self._contexts: Dict[str, asyncio.Queue] = {}
-            self._audio_context_task = self.create_task(self._audio_context_task_handler())
-
-    async def _stop_audio_context_task(self):
-        if self._audio_context_task:
-            await self.cancel_task(self._audio_context_task)
-            self._audio_context_task = None
-
-    async def _audio_context_task_handler(self):
-        """In this task we process audio contexts in order."""
-        running = True
-        while running:
-            context_id = await self._contexts_queue.get()
-
-            if context_id:
-                # Process the audio context until the context doesn't have more
-                # audio available (i.e. we find None).
-                await self._handle_audio_context(context_id)
-
-                # We just finished processing the context, so we can safely remove it.
-                del self._contexts[context_id]
-
-                # Append some silence between sentences.
-                silence = b"\x00" * self.sample_rate
-                frame = TTSAudioRawFrame(
-                    audio=silence, sample_rate=self.sample_rate, num_channels=1
-                )
-                await self.push_frame(frame)
-            else:
-                running = False
-
-            self._contexts_queue.task_done()
-
-    async def _handle_audio_context(self, context_id: str):
-        # If we don't receive any audio during this time, we consider the context finished.
-        AUDIO_CONTEXT_TIMEOUT = 3.0
-        queue = self._contexts[context_id]
-        running = True
-        while running:
-            try:
-                frame = await asyncio.wait_for(queue.get(), timeout=AUDIO_CONTEXT_TIMEOUT)
-                if frame:
-                    await self.push_frame(frame)
-                running = frame is not None
-            except asyncio.TimeoutError:
-                # We didn't get audio, so let's consider this context finished.
-                logger.trace(f"{self} time out on audio context {context_id}")
-                break
+        await self._disconnect()
 
     def can_generate_metrics(self) -> bool:
         """Check if this service can generate processing metrics.