From 3d88b42e0b533e4dcdb9283d06c77b7d7ecf39fa Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Aleix=20Conchillo=20Flaqu=C3=A9?= Date: Fri, 19 Sep 2025 13:44:49 -0700 Subject: [PATCH 1/2] FrameProcessor: add before/after events for processed/pushed frames --- CHANGELOG.md | 6 +++ src/pipecat/processors/frame_processor.py | 20 ++++++++++ tests/test_frame_processor.py | 45 +++++++++++++++++++++++ 3 files changed, 71 insertions(+) diff --git a/CHANGELOG.md b/CHANGELOG.md index 65d3c388f..bc432db50 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -9,6 +9,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 ### Added +- Added `on_before_process_frame`, `on_after_process_frame`, + `on_before_push_frame` and `on_after_push_frame`. These are synchronous events + that get called before and after a frame is processed or pushed. Note that + these events are synchrnous so they should ideally perform lightweight tasks + in order to not block the pipeline. + - Added `on_before_leave` synchronous event to `DailyTransport`. - Added `on_before_disconnect` synchronous event to `LiveKitTransport`. diff --git a/src/pipecat/processors/frame_processor.py b/src/pipecat/processors/frame_processor.py index 5723512a3..894dabbe7 100644 --- a/src/pipecat/processors/frame_processor.py +++ b/src/pipecat/processors/frame_processor.py @@ -141,6 +141,12 @@ class FrameProcessor(BaseObject): task. System frames are also processed in a separate task which guarantees frame priority. + Event handlers available: + + - on_before_process_frame: Called before a frame is processed + - on_after_process_frame: Called after a frame is processed + - on_before_push_frame: Called before a frame is pushed + - on_after_push_frame: Called after a frame is pushed """ def __init__( @@ -228,6 +234,12 @@ class FrameProcessor(BaseObject): self._wait_for_interruption = False self._wait_interruption_event = asyncio.Event() + # Frame processor events. + self._register_event_handler("on_before_process_frame", sync=True) + self._register_event_handler("on_after_process_frame", sync=True) + self._register_event_handler("on_before_push_frame", sync=True) + self._register_event_handler("on_after_push_frame", sync=True) + @property def id(self) -> int: """Get the unique identifier for this processor. @@ -639,8 +651,12 @@ class FrameProcessor(BaseObject): if not self._check_started(frame): return + await self._call_event_handler("on_before_push_frame", frame) + await self.__internal_push_frame(frame, direction) + await self._call_event_handler("on_after_push_frame", frame) + # If we are waiting for an interruption and we get an interruption, then # we can unblock `push_interruption_task_frame_and_wait()`. if self._wait_for_interruption and isinstance(frame, InterruptionFrame): @@ -836,11 +852,15 @@ class FrameProcessor(BaseObject): self, frame: Frame, direction: FrameDirection, callback: Optional[FrameCallback] ): try: + await self._call_event_handler("on_before_process_frame", frame) + # Process the frame. await self.process_frame(frame, direction) # If this frame has an associated callback, call it now. if callback: await callback(self, frame, direction) + + await self._call_event_handler("on_after_process_frame", frame) except Exception as e: logger.exception(f"{self}: error processing frame: {e}") await self.push_error(ErrorFrame(str(e))) diff --git a/tests/test_frame_processor.py b/tests/test_frame_processor.py index 7cbe258f8..f514c94b0 100644 --- a/tests/test_frame_processor.py +++ b/tests/test_frame_processor.py @@ -15,11 +15,56 @@ from pipecat.frames.frames import ( TransportMessageUrgentFrame, ) from pipecat.pipeline.pipeline import Pipeline +from pipecat.processors.filters.identity_filter import IdentityFilter from pipecat.processors.frame_processor import FrameDirection, FrameProcessor from pipecat.tests.utils import SleepFrame, run_test class TestFrameProcessor(unittest.IsolatedAsyncioTestCase): + async def test_before_after_events(self): + identity = IdentityFilter() + + before_process_called = False + after_process_called = False + before_push_called = False + after_push_called = False + + @identity.event_handler("on_before_process_frame") + async def on_before_process_frame(filter, frame): + nonlocal before_process_called + before_process_called = True + + @identity.event_handler("on_after_process_frame") + async def on_after_process_frame(filter, frame): + nonlocal after_process_called + after_process_called = True + + @identity.event_handler("on_before_push_frame") + async def on_before_push_frame(filter, frame): + nonlocal before_push_called + before_push_called = True + + @identity.event_handler("on_after_push_frame") + async def on_after_push_frame(filter, frame): + nonlocal after_push_called + after_push_called = True + + pipeline = Pipeline([identity]) + + frames_to_send = [TextFrame(text="Hello cat!")] + + expected_down_frames = [TextFrame] + + await run_test( + pipeline, + frames_to_send=frames_to_send, + expected_down_frames=expected_down_frames, + ) + assert before_process_called + assert after_process_called + assert before_push_called + assert after_push_called + async def test_interruption_and_wait(self): class DelayFrameProcessor(FrameProcessor): """This processors just gives time to the event loop to change From ec664e2d33b2bba9f57c245ca2f112c3d65dee89 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Aleix=20Conchillo=20Flaqu=C3=A9?= Date: Sat, 20 Sep 2025 10:21:55 -0700 Subject: [PATCH 2/2] examples(foundational): added 45-before-and-afet-events.py --- CHANGELOG.md | 3 +- .../45-before-and-after-events.py | 150 ++++++++++++++++++ 2 files changed, 152 insertions(+), 1 deletion(-) create mode 100644 examples/foundational/45-before-and-after-events.py diff --git a/CHANGELOG.md b/CHANGELOG.md index bc432db50..41d905d43 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -13,7 +13,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 `on_before_push_frame` and `on_after_push_frame`. These are synchronous events that get called before and after a frame is processed or pushed. Note that these events are synchrnous so they should ideally perform lightweight tasks - in order to not block the pipeline. + in order to not block the pipeline. See + `examples/foundational/45-before-and-after-events.py`. - Added `on_before_leave` synchronous event to `DailyTransport`. diff --git a/examples/foundational/45-before-and-after-events.py b/examples/foundational/45-before-and-after-events.py new file mode 100644 index 000000000..eca4de7df --- /dev/null +++ b/examples/foundational/45-before-and-after-events.py @@ -0,0 +1,150 @@ +# +# Copyright (c) 2024–2025, Daily +# +# SPDX-License-Identifier: BSD 2-Clause License +# + +import os +from dataclasses import dataclass + +from dotenv import load_dotenv +from loguru import logger + +from pipecat.audio.turn.smart_turn.base_smart_turn import SmartTurnParams +from pipecat.audio.turn.smart_turn.local_smart_turn_v3 import LocalSmartTurnAnalyzerV3 +from pipecat.audio.vad.silero import SileroVADAnalyzer +from pipecat.audio.vad.vad_analyzer import VADParams +from pipecat.frames.frames import DataFrame, LLMRunFrame +from pipecat.pipeline.pipeline import Pipeline +from pipecat.pipeline.runner import PipelineRunner +from pipecat.pipeline.task import PipelineParams, PipelineTask +from pipecat.processors.aggregators.openai_llm_context import OpenAILLMContext +from pipecat.runner.types import RunnerArguments +from pipecat.runner.utils import create_transport +from pipecat.services.cartesia.tts import CartesiaTTSService +from pipecat.services.deepgram.stt import DeepgramSTTService +from pipecat.services.openai.llm import OpenAILLMService +from pipecat.transports.base_transport import BaseTransport, TransportParams +from pipecat.transports.daily.transport import DailyParams +from pipecat.transports.websocket.fastapi import FastAPIWebsocketParams + +load_dotenv(override=True) + + +@dataclass +class CustomBeforeProcessFrame(DataFrame): + pass + + +@dataclass +class CustomAfterPushFrame(DataFrame): + pass + + +# We store functions so objects (e.g. SileroVADAnalyzer) don't get +# instantiated. The function will be called when the desired transport gets +# selected. +transport_params = { + "daily": lambda: DailyParams( + audio_in_enabled=True, + audio_out_enabled=True, + vad_analyzer=SileroVADAnalyzer(params=VADParams(stop_secs=0.2)), + turn_analyzer=LocalSmartTurnAnalyzerV3(params=SmartTurnParams()), + ), + "twilio": lambda: FastAPIWebsocketParams( + audio_in_enabled=True, + audio_out_enabled=True, + vad_analyzer=SileroVADAnalyzer(params=VADParams(stop_secs=0.2)), + turn_analyzer=LocalSmartTurnAnalyzerV3(params=SmartTurnParams()), + ), + "webrtc": lambda: TransportParams( + audio_in_enabled=True, + audio_out_enabled=True, + vad_analyzer=SileroVADAnalyzer(params=VADParams(stop_secs=0.2)), + turn_analyzer=LocalSmartTurnAnalyzerV3(params=SmartTurnParams()), + ), +} + + +async def run_bot(transport: BaseTransport, runner_args: RunnerArguments): + logger.info(f"Starting bot") + + stt = DeepgramSTTService(api_key=os.getenv("DEEPGRAM_API_KEY")) + + tts = CartesiaTTSService( + api_key=os.getenv("CARTESIA_API_KEY"), + voice_id="71a7ad14-091c-4e8e-a314-022ece01c121", # British Reading Lady + ) + + llm = OpenAILLMService(api_key=os.getenv("OPENAI_API_KEY")) + + messages = [ + { + "role": "system", + "content": "You are a helpful LLM in a WebRTC call. Your goal is to demonstrate your capabilities in a succinct way. Your output will be converted to audio so don't include special characters in your answers. Respond to what the user said in a creative and helpful way.", + }, + ] + + context = OpenAILLMContext(messages) + context_aggregator = llm.create_context_aggregator(context) + + pipeline = Pipeline( + [ + transport.input(), # Transport user input + stt, + context_aggregator.user(), # User responses + llm, # LLM + tts, # TTS + transport.output(), # Transport bot output + context_aggregator.assistant(), # Assistant spoken responses + ] + ) + + task = PipelineTask( + pipeline, + params=PipelineParams( + enable_metrics=True, + enable_usage_metrics=True, + ), + idle_timeout_secs=runner_args.pipeline_idle_timeout_secs, + ) + + @transport.output().event_handler("on_before_process_frame") + async def transport_on_before_process_frame(transport, frame): + if isinstance(frame, CustomBeforeProcessFrame): + logger.info("*** CUSTOM FRAME RECEIVED. Bot is about to talk, let's do something!") + + @transport.output().event_handler("on_after_push_frame") + async def transport_on_after_push_frame(transport, frame): + if isinstance(frame, CustomAfterPushFrame): + logger.info("*** CUSTOM FRAME RECEIVED. Bot has stopped talking, let's do something!") + + @transport.event_handler("on_client_connected") + async def on_client_connected(transport, client): + logger.info(f"Client connected") + # Kick off the conversation. + messages.append({"role": "system", "content": "Please introduce yourself to the user."}) + # CustomSynchronizationFrame is pushed in order so it will reach the + # `on_after_push_frame` handler before the bot has finished talking. + await task.queue_frames([CustomBeforeProcessFrame(), LLMRunFrame(), CustomAfterPushFrame()]) + + @transport.event_handler("on_client_disconnected") + async def on_client_disconnected(transport, client): + logger.info(f"Client disconnected") + await task.cancel() + + runner = PipelineRunner(handle_sigint=runner_args.handle_sigint) + + await runner.run(task) + + +async def bot(runner_args: RunnerArguments): + """Main bot entry point compatible with Pipecat Cloud.""" + transport = await create_transport(runner_args, transport_params) + await run_bot(transport, runner_args) + + +if __name__ == "__main__": + from pipecat.runner.run import main + + main()