mirror of
https://github.com/hwchase17/langchain
synced 2024-11-06 03:20:49 +00:00
ddaf9de169
- **Description:** Fix Streamlit bug which was introduced by https://github.com/langchain-ai/langchain/pull/18250, update integration test - **Issue:** https://github.com/langchain-ai/langchain/issues/18684 - **Dependencies:** None
48 lines
1.4 KiB
Python
48 lines
1.4 KiB
Python
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]
|
|
self._key = key
|
|
|
|
@property
|
|
def messages(self) -> List[BaseMessage]:
|
|
"""Retrieve the current list of messages"""
|
|
return self._messages
|
|
|
|
@messages.setter
|
|
def messages(self, value: List[BaseMessage]) -> None:
|
|
"""Set the messages list with a new value"""
|
|
import streamlit as st
|
|
|
|
st.session_state[self._key] = value
|
|
self._messages = st.session_state[self._key]
|
|
|
|
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()
|