Spaces:
Runtime error
Runtime error
File size: 1,176 Bytes
129cd69 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 |
from typing import List
from langchain_core.chat_history import BaseChatMessageHistory
from langchain_core.messages import BaseMessage
class StreamlitChatMessageHistory(BaseChatMessageHistory):
"""
Chat message history that stores messages in Streamlit session state.
Args:
key: The key to use in Streamlit session state for storing messages.
"""
def __init__(self, key: str = "langchain_messages"):
try:
import streamlit as st
except ImportError as e:
raise ImportError(
"Unable to import streamlit, please run `pip install streamlit`."
) from e
if key not in st.session_state:
st.session_state[key] = []
self._messages = st.session_state[key]
@property
def messages(self) -> List[BaseMessage]: # type: ignore
"""Retrieve the current list of messages"""
return self._messages
def add_message(self, message: BaseMessage) -> None:
"""Add a message to the session memory"""
self._messages.append(message)
def clear(self) -> None:
"""Clear session memory"""
self._messages.clear()
|