# # Copyright (c) 2024–2025, Daily # # SPDX-License-Identifier: BSD 2-Clause License # import argparse import os from dotenv import load_dotenv from langchain.prompts import ChatPromptTemplate, MessagesPlaceholder from langchain_community.chat_message_histories import ChatMessageHistory from langchain_core.chat_history import BaseChatMessageHistory from langchain_core.runnables.history import RunnableWithMessageHistory from langchain_openai import ChatOpenAI from loguru import logger from pipecat.audio.vad.silero import SileroVADAnalyzer from pipecat.frames.frames import LLMMessagesFrame from pipecat.pipeline.pipeline import Pipeline from pipecat.pipeline.runner import PipelineRunner from pipecat.pipeline.task import PipelineParams, PipelineTask from pipecat.processors.aggregators.llm_response import ( LLMAssistantResponseAggregator, LLMUserResponseAggregator, ) from pipecat.processors.frameworks.langchain import LangchainProcessor from pipecat.services.cartesia.tts import CartesiaTTSService from pipecat.services.deepgram.stt import DeepgramSTTService from pipecat.transports.base_transport import TransportParams from pipecat.transports.network.small_webrtc import SmallWebRTCTransport from pipecat.transports.network.webrtc_connection import SmallWebRTCConnection load_dotenv(override=True) message_store = {} def get_session_history(session_id: str) -> BaseChatMessageHistory: if session_id not in message_store: message_store[session_id] = ChatMessageHistory() return message_store[session_id] async def run_bot(webrtc_connection: SmallWebRTCConnection, _: argparse.Namespace): logger.info(f"Starting bot") transport = SmallWebRTCTransport( webrtc_connection=webrtc_connection, params=TransportParams( audio_in_enabled=True, audio_out_enabled=True, vad_analyzer=SileroVADAnalyzer(), ), ) 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 ) prompt = ChatPromptTemplate.from_messages( [ ( "system", "Be nice and helpful. Answer very briefly and without special characters like `#` or `*`. " "Your response will be synthesized to voice and those characters will create unnatural sounds.", ), MessagesPlaceholder("chat_history"), ("human", "{input}"), ] ) chain = prompt | ChatOpenAI(model="gpt-4.1", temperature=0.7) history_chain = RunnableWithMessageHistory( chain, get_session_history, history_messages_key="chat_history", input_messages_key="input", ) lc = LangchainProcessor(history_chain) tma_in = LLMUserResponseAggregator() tma_out = LLMAssistantResponseAggregator() pipeline = Pipeline( [ transport.input(), # Transport user input stt, tma_in, # User responses lc, # Langchain tts, # TTS transport.output(), # Transport bot output tma_out, # Assistant spoken responses ] ) task = PipelineTask( pipeline, params=PipelineParams( allow_interruptions=True, enable_metrics=True, enable_usage_metrics=True, report_only_initial_ttfb=True, ), ) @transport.event_handler("on_client_connected") async def on_client_connected(transport, client): logger.info(f"Client connected") # Kick off the conversation. # the `LLMMessagesFrame` will be picked up by the LangchainProcessor using # only the content of the last message to inject it in the prompt defined # above. So no role is required here. messages = [({"content": "Please briefly introduce yourself to the user."})] await task.queue_frames([LLMMessagesFrame(messages)]) @transport.event_handler("on_client_disconnected") async def on_client_disconnected(transport, client): logger.info(f"Client disconnected") @transport.event_handler("on_client_closed") async def on_client_closed(transport, client): logger.info(f"Client closed connection") await task.cancel() runner = PipelineRunner(handle_sigint=False) await runner.run(task) if __name__ == "__main__": from run import main main()