uses sentinel object when end of transcription, to properly terminate tasks

whisperlivekit/audio_processor.py

@@ -15,6 +15,8 @@ logging.basicConfig(level=logging.INFO, format="%(asctime)s - %(levelname)s - %(
 logger = logging.getLogger(__name__)
 logger.setLevel(logging.DEBUG)
 
+SENTINEL = object() # unique sentinel object for end of stream marker
+
 def format_time(seconds: float) -> str:
     """Format seconds as HH:MM:SS."""
     return str(timedelta(seconds=int(seconds)))
@@ -41,8 +43,9 @@ class AudioProcessor:
         self.last_ffmpeg_activity = time()
         self.ffmpeg_health_check_interval = 5
         self.ffmpeg_max_idle_time = 10
- 
+
         # State management
+        self.is_stopping = False
         self.tokens = []
         self.buffer_transcription = ""
         self.buffer_diarization = ""
@@ -62,6 +65,13 @@ class AudioProcessor:
         self.transcription_queue = asyncio.Queue() if self.args.transcription else None
         self.diarization_queue = asyncio.Queue() if self.args.diarization else None
         self.pcm_buffer = bytearray()
+
+        # Task references
+        self.transcription_task = None
+        self.diarization_task = None
+        self.ffmpeg_reader_task = None
+        self.watchdog_task = None
+        self.all_tasks_for_cleanup = []
         
         # Initialize transcription engine if enabled
         if self.args.transcription:
@@ -210,7 +220,7 @@ class AudioProcessor:
                     self.last_ffmpeg_activity = time()
                         
                 if not chunk:
-                    logger.info("FFmpeg stdout closed.")
+                    logger.info("FFmpeg stdout closed, no more data to read.")
                     break
                     
                 self.pcm_buffer.extend(chunk)
@@ -245,6 +255,15 @@ class AudioProcessor:
                 logger.warning(f"Exception in ffmpeg_stdout_reader: {e}")
                 logger.warning(f"Traceback: {traceback.format_exc()}")
                 break
+        
+        logger.info("FFmpeg stdout processing finished. Signaling downstream processors.")
+        if self.args.transcription and self.transcription_queue:
+            await self.transcription_queue.put(SENTINEL)
+            logger.debug("Sentinel put into transcription_queue.")
+        if self.args.diarization and self.diarization_queue:
+            await self.diarization_queue.put(SENTINEL)
+            logger.debug("Sentinel put into diarization_queue.")
+
 
     async def transcription_processor(self):
         """Process audio chunks for transcription."""
@@ -254,7 +273,16 @@ class AudioProcessor:
         while True:
             try:
                 pcm_array = await self.transcription_queue.get()
+                if pcm_array is SENTINEL:
+                    logger.debug("Transcription processor received sentinel. Finishing.")
+                    self.transcription_queue.task_done()
+                    break
                 
+                if not self.online: # Should not happen if queue is used
+                    logger.warning("Transcription processor: self.online not initialized.")
+                    self.transcription_queue.task_done()
+                    continue
+
                 logger.info(f"{len(self.online.audio_buffer) / self.online.SAMPLING_RATE} seconds of audio to process.")
                 
                 # Process transcription
@@ -278,12 +306,15 @@ class AudioProcessor:
                 await self.update_transcription(
                     new_tokens, buffer, end_buffer, self.full_transcription, self.sep
                 )
+                self.transcription_queue.task_done()
                 
             except Exception as e:
                 logger.warning(f"Exception in transcription_processor: {e}")
                 logger.warning(f"Traceback: {traceback.format_exc()}")
-            finally:
-                self.transcription_queue.task_done()
+                if 'pcm_array' in locals() and pcm_array is not SENTINEL : # Check if pcm_array was assigned from queue
+                    self.transcription_queue.task_done()
+        logger.info("Transcription processor task finished.")
+
 
     async def diarization_processor(self, diarization_obj):
         """Process audio chunks for speaker diarization."""
@@ -292,6 +323,10 @@ class AudioProcessor:
         while True:
             try:
                 pcm_array = await self.diarization_queue.get()
+                if pcm_array is SENTINEL:
+                    logger.debug("Diarization processor received sentinel. Finishing.")
+                    self.diarization_queue.task_done()
+                    break
                 
                 # Process diarization
                 await diarization_obj.diarize(pcm_array)
@@ -303,12 +338,15 @@ class AudioProcessor:
                 )
                 
                 await self.update_diarization(new_end, buffer_diarization)
+                self.diarization_queue.task_done()
                 
             except Exception as e:
                 logger.warning(f"Exception in diarization_processor: {e}")
                 logger.warning(f"Traceback: {traceback.format_exc()}")
-            finally:
-                self.diarization_queue.task_done()
+                if 'pcm_array' in locals() and pcm_array is not SENTINEL:
+                    self.diarization_queue.task_done()
+        logger.info("Diarization processor task finished.")
+
 
     async def results_formatter(self):
         """Format processing results for output."""
@@ -398,6 +436,19 @@ class AudioProcessor:
                     yield response
                     self.last_response_content = response_content
                 
+                # Check for termination condition
+                if self.is_stopping:
+                    all_processors_done = True
+                    if self.args.transcription and self.transcription_task and not self.transcription_task.done():
+                        all_processors_done = False
+                    if self.args.diarization and self.diarization_task and not self.diarization_task.done():
+                        all_processors_done = False
+                    
+                    if all_processors_done:
+                        logger.info("Results formatter: All upstream processors are done and in stopping state. Terminating.")
+                        final_state = await self.get_current_state()
+                        return
+                
                 await asyncio.sleep(0.1)  # Avoid overwhelming the client
                 
             except Exception as e:
@@ -407,65 +458,117 @@ class AudioProcessor:
         
     async def create_tasks(self):
         """Create and start processing tasks."""
-            
-        tasks = []    
+        self.all_tasks_for_cleanup = []
+        processing_tasks_for_watchdog = []
+
         if self.args.transcription and self.online:
-            tasks.append(asyncio.create_task(self.transcription_processor()))
+            self.transcription_task = asyncio.create_task(self.transcription_processor())
+            self.all_tasks_for_cleanup.append(self.transcription_task)
+            processing_tasks_for_watchdog.append(self.transcription_task)
             
         if self.args.diarization and self.diarization:
-            tasks.append(asyncio.create_task(self.diarization_processor(self.diarization)))
+            self.diarization_task = asyncio.create_task(self.diarization_processor(self.diarization))
+            self.all_tasks_for_cleanup.append(self.diarization_task)
+            processing_tasks_for_watchdog.append(self.diarization_task)
         
-        tasks.append(asyncio.create_task(self.ffmpeg_stdout_reader()))
-        
-        # Monitor overall system health
-        async def watchdog():
-            while True:
-                try:
-                    await asyncio.sleep(10)  # Check every 10 seconds instead of 60
-                    
-                    current_time = time()
-                    # Check for stalled tasks
-                    for i, task in enumerate(tasks):
-                        if task.done():
-                            exc = task.exception() if task.done() else None
-                            task_name = task.get_name() if hasattr(task, 'get_name') else f"Task {i}"
-                            logger.error(f"{task_name} unexpectedly completed with exception: {exc}")
-                    
-                    # Check for FFmpeg process health with shorter thresholds
-                    ffmpeg_idle_time = current_time - self.last_ffmpeg_activity
-                    if ffmpeg_idle_time > 15:  # 15 seconds instead of 180
-                        logger.warning(f"FFmpeg idle for {ffmpeg_idle_time:.2f}s - may need attention")
-                        
-                        # Force restart after 30 seconds of inactivity (instead of 600)
-                        if ffmpeg_idle_time > 30:
-                            logger.error("FFmpeg idle for too long, forcing restart")
-                            await self.restart_ffmpeg()
-                            
-                except Exception as e:
-                    logger.error(f"Error in watchdog task: {e}")
+        self.ffmpeg_reader_task = asyncio.create_task(self.ffmpeg_stdout_reader())
+        self.all_tasks_for_cleanup.append(self.ffmpeg_reader_task)
+        processing_tasks_for_watchdog.append(self.ffmpeg_reader_task)
 
-        tasks.append(asyncio.create_task(watchdog()))
-        self.tasks = tasks
+        # Monitor overall system health
+        self.watchdog_task = asyncio.create_task(self.watchdog(processing_tasks_for_watchdog))
+        self.all_tasks_for_cleanup.append(self.watchdog_task)
         
         return self.results_formatter()
+
+    async def watchdog(self, tasks_to_monitor):
+        """Monitors the health of critical processing tasks."""
+        while True:
+            try:
+                await asyncio.sleep(10)
+                current_time = time()
+
+                for i, task in enumerate(tasks_to_monitor):
+                    if task.done():
+                        exc = task.exception()
+                        task_name = task.get_name() if hasattr(task, 'get_name') else f"Monitored Task {i}"
+                        if exc:
+                            logger.error(f"{task_name} unexpectedly completed with exception: {exc}")
+                        else:
+                            logger.info(f"{task_name} completed normally.")
+                
+                ffmpeg_idle_time = current_time - self.last_ffmpeg_activity
+                if ffmpeg_idle_time > 15:
+                    logger.warning(f"FFmpeg idle for {ffmpeg_idle_time:.2f}s - may need attention.")
+                    if ffmpeg_idle_time > 30 and not self.is_stopping:
+                        logger.error("FFmpeg idle for too long and not in stopping phase, forcing restart.")
+                        await self.restart_ffmpeg()
+            except asyncio.CancelledError:
+                logger.info("Watchdog task cancelled.")
+                break
+            except Exception as e:
+                logger.error(f"Error in watchdog task: {e}", exc_info=True)
         
     async def cleanup(self):
         """Clean up resources when processing is complete."""
-        for task in self.tasks:
-            task.cancel()
+        logger.info("Starting cleanup of AudioProcessor resources.")
+        for task in self.all_tasks_for_cleanup:
+            if task and not task.done():
+                task.cancel()
+        
+        created_tasks = [t for t in self.all_tasks_for_cleanup if t]
+        if created_tasks:
+            await asyncio.gather(*created_tasks, return_exceptions=True)
+        logger.info("All processing tasks cancelled or finished.")
+
+        if self.ffmpeg_process:
+            if self.ffmpeg_process.stdin and not self.ffmpeg_process.stdin.closed:
+                try:
+                    self.ffmpeg_process.stdin.close()
+                except Exception as e:
+                    logger.warning(f"Error closing ffmpeg stdin during cleanup: {e}")
             
-        try:
-            await asyncio.gather(*self.tasks, return_exceptions=True)
-            self.ffmpeg_process.stdin.close()
-            self.ffmpeg_process.wait()
-        except Exception as e:
-            logger.warning(f"Error during cleanup: {e}")
-            
-        if self.args.diarization and hasattr(self, 'diarization'):
+            # Wait for ffmpeg process to terminate
+            if self.ffmpeg_process.poll() is None: # Check if process is still running
+                logger.info("Waiting for FFmpeg process to terminate...")
+                try:
+                    # Run wait in executor to avoid blocking async loop
+                    await asyncio.get_event_loop().run_in_executor(None, self.ffmpeg_process.wait, 5.0) # 5s timeout
+                except Exception as e: # subprocess.TimeoutExpired is not directly caught by asyncio.wait_for with run_in_executor
+                    logger.warning(f"FFmpeg did not terminate gracefully, killing. Error: {e}")
+                    self.ffmpeg_process.kill()
+                    await asyncio.get_event_loop().run_in_executor(None, self.ffmpeg_process.wait) # Wait for kill
+            logger.info("FFmpeg process terminated.")
+
+        if self.args.diarization and hasattr(self, 'diarization') and hasattr(self.diarization, 'close'):
             self.diarization.close()
+        logger.info("AudioProcessor cleanup complete.")
+
 
     async def process_audio(self, message):
         """Process incoming audio data."""
+        # If already stopping or stdin is closed, ignore further audio, especially residual chunks.
+        if self.is_stopping or (self.ffmpeg_process and self.ffmpeg_process.stdin and self.ffmpeg_process.stdin.closed):
+            logger.warning(f"AudioProcessor is stopping or stdin is closed. Ignoring incoming audio message (length: {len(message)}).")
+            if not message and self.ffmpeg_process and self.ffmpeg_process.stdin and not self.ffmpeg_process.stdin.closed:
+                 logger.info("Received empty message while already in stopping state; ensuring stdin is closed.")
+                 try:
+                    self.ffmpeg_process.stdin.close()
+                 except Exception as e:
+                    logger.warning(f"Error closing ffmpeg stdin on redundant stop signal during stopping state: {e}")
+            return
+
+        if not message: # primary signal to start stopping
+            logger.info("Empty audio message received, initiating stop sequence.")
+            self.is_stopping = True
+            if self.ffmpeg_process and self.ffmpeg_process.stdin and not self.ffmpeg_process.stdin.closed:
+                try:
+                    self.ffmpeg_process.stdin.close()
+                    logger.info("FFmpeg stdin closed due to primary stop signal.")
+                except Exception as e:
+                    logger.warning(f"Error closing ffmpeg stdin on stop: {e}")
+            return
+
         retry_count = 0
         max_retries = 3
         
@@ -517,4 +620,4 @@ class AudioProcessor:
                 else:
                     logger.error("Maximum retries reached for FFmpeg process")
                     await self.restart_ffmpeg()
-                    return
+                    return