import os | |
# Import the PipelineRunnable from pipeline.py | |
from pipeline import pipeline_runnable | |
from langchain_core.chat_history import BaseChatMessageHistory | |
from langchain_community.chat_message_histories import ChatMessageHistory | |
from langchain_core.runnables.history import RunnableWithMessageHistory | |
############################################################################### | |
# 1) In-memory store: session_id -> ChatMessageHistory | |
############################################################################### | |
store = {} # e.g. { "abc123": ChatMessageHistory() } | |
def get_session_history(session_id: str) -> BaseChatMessageHistory: | |
if session_id not in store: | |
store[session_id] = ChatMessageHistory() | |
return store[session_id] | |
############################################################################### | |
# 2) Create RunnableWithMessageHistory | |
############################################################################### | |
conversational_rag_chain = RunnableWithMessageHistory( | |
pipeline_runnable, | |
get_session_history, | |
input_messages_key="input", | |
history_messages_key="chat_history", | |
output_messages_key="answer" | |
) | |
############################################################################### | |
# 3) Convenience function for session-based memory | |
############################################################################### | |
def run_with_session_memory(user_query: str, session_id: str) -> str: | |
if not user_query: | |
raise ValueError("User query is missing. Ensure the 'input' key is provided.") | |
# Prepare input dictionary with the correct structure | |
input_data = {"input": user_query} | |
# Ensure the session ID is passed correctly in the configuration | |
response = conversational_rag_chain.invoke( | |
input_data, # Pass the dictionary containing the 'input' key | |
config={"configurable": {"session_id": session_id}} # Pass session ID in the config | |
) | |
return response.get("answer", "No answer returned from the chain.") | |