forked from Archives/langchain
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
46 lines
1.3 KiB
Python
46 lines
1.3 KiB
Python
import json
|
|
import logging
|
|
from pathlib import Path
|
|
from typing import List
|
|
|
|
from langchain.schema import (
|
|
BaseChatMessageHistory,
|
|
BaseMessage,
|
|
messages_from_dict,
|
|
messages_to_dict,
|
|
)
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class FileChatMessageHistory(BaseChatMessageHistory):
|
|
"""
|
|
Chat message history that stores history in a local file.
|
|
|
|
Args:
|
|
file_path: path of the local file to store the messages.
|
|
"""
|
|
|
|
def __init__(self, file_path: str):
|
|
self.file_path = Path(file_path)
|
|
if not self.file_path.exists():
|
|
self.file_path.touch()
|
|
self.file_path.write_text(json.dumps([]))
|
|
|
|
@property
|
|
def messages(self) -> List[BaseMessage]: # type: ignore
|
|
"""Retrieve the messages from the local file"""
|
|
items = json.loads(self.file_path.read_text())
|
|
messages = messages_from_dict(items)
|
|
return messages
|
|
|
|
def add_message(self, message: BaseMessage) -> None:
|
|
"""Append the message to the record in the local file"""
|
|
messages = messages_to_dict(self.messages)
|
|
messages.append(messages_to_dict([message])[0])
|
|
self.file_path.write_text(json.dumps(messages))
|
|
|
|
def clear(self) -> None:
|
|
"""Clear session memory from the local file"""
|
|
self.file_path.write_text(json.dumps([]))
|