langflow/src/backend/langflow/api/chat_manager.py
Gabriel Almeida e0364833a9 🔥 refactor(chat_manager.py): rename filter parameter to filter_messages for clarity
🔥 refactor(custom.py): remove unused import of SQL_FORMAT_INSTRUCTIONS
🔥 refactor(custom_lists.py): remove unused import of SQLDatabase and utility_type_to_cls_dict
🔥 refactor(utilities/base.py): remove unused import of utility_type_to_cls_dict
🔥 refactor(utils/util.py): remove unused function build_template_from_parameters
The changes made are mostly removing unused imports and renaming a parameter for clarity. The import of SQL_FORMAT_INSTRUCTIONS was removed as it was not being used. The function build_template_from_parameters was removed as it was not being used.
2023-05-27 16:53:57 -03:00

221 lines
8.3 KiB
Python

import asyncio
import json
from collections import defaultdict
from typing import Dict, List
from fastapi import WebSocket, status
from langflow.api.schemas import ChatMessage, ChatResponse, FileResponse
from langflow.cache import cache_manager
from langflow.cache.manager import Subject
from langflow.interface.run import (
get_result_and_steps,
load_or_build_langchain_object,
)
from langflow.interface.utils import pil_to_base64, try_setting_streaming_options
from langflow.utils.logger import logger
class ChatHistory(Subject):
def __init__(self):
super().__init__()
self.history: Dict[str, List[ChatMessage]] = defaultdict(list)
def add_message(self, client_id: str, message: ChatMessage):
"""Add a message to the chat history."""
self.history[client_id].append(message)
if not isinstance(message, FileResponse):
self.notify()
def get_history(self, client_id: str, filter_messages=True) -> List[ChatMessage]:
"""Get the chat history for a client."""
if history := self.history.get(client_id, []):
if filter_messages:
return [msg for msg in history if msg.type not in ["start", "stream"]]
return history
else:
return []
def empty_history(self, client_id: str):
"""Empty the chat history for a client."""
self.history[client_id] = []
class ChatManager:
def __init__(self):
self.active_connections: Dict[str, WebSocket] = {}
self.chat_history = ChatHistory()
self.cache_manager = cache_manager
self.cache_manager.attach(self.update)
def on_chat_history_update(self):
"""Send the last chat message to the client."""
client_id = self.cache_manager.current_client_id
if client_id in self.active_connections:
chat_response = self.chat_history.get_history(client_id, filter=False)[-1]
if chat_response.is_bot:
# Process FileResponse
if isinstance(chat_response, FileResponse):
# If data_type is pandas, convert to csv
if chat_response.data_type == "pandas":
chat_response.data = chat_response.data.to_csv()
elif chat_response.data_type == "image":
# Base64 encode the image
chat_response.data = pil_to_base64(chat_response.data)
# get event loop
loop = asyncio.get_event_loop()
coroutine = self.send_json(client_id, chat_response)
asyncio.run_coroutine_threadsafe(coroutine, loop)
def update(self):
if self.cache_manager.current_client_id in self.active_connections:
self.last_cached_object_dict = self.cache_manager.get_last()
# Add a new ChatResponse with the data
chat_response = FileResponse(
message=None,
type="file",
data=self.last_cached_object_dict["obj"],
data_type=self.last_cached_object_dict["type"],
)
self.chat_history.add_message(
self.cache_manager.current_client_id, chat_response
)
async def connect(self, client_id: str, websocket: WebSocket):
await websocket.accept()
self.active_connections[client_id] = websocket
def disconnect(self, client_id: str):
self.active_connections.pop(client_id, None)
async def send_message(self, client_id: str, message: str):
websocket = self.active_connections[client_id]
await websocket.send_text(message)
async def send_json(self, client_id: str, message: ChatMessage):
websocket = self.active_connections[client_id]
await websocket.send_json(message.dict())
async def process_message(self, client_id: str, payload: Dict):
# Process the graph data and chat message
chat_message = payload.pop("message", "")
chat_message = ChatMessage(message=chat_message)
self.chat_history.add_message(client_id, chat_message)
graph_data = payload
start_resp = ChatResponse(message=None, type="start", intermediate_steps="")
await self.send_json(client_id, start_resp)
is_first_message = len(self.chat_history.get_history(client_id=client_id)) <= 1
# Generate result and thought
try:
logger.debug("Generating result and thought")
result, intermediate_steps = await process_graph(
graph_data=graph_data,
is_first_message=is_first_message,
chat_message=chat_message,
websocket=self.active_connections[client_id],
)
except Exception as e:
# Log stack trace
logger.exception(e)
self.chat_history.empty_history(client_id)
raise e
# Send a response back to the frontend, if needed
intermediate_steps = intermediate_steps or ""
history = self.chat_history.get_history(client_id, filter=False)
file_responses = []
if history:
# Iterate backwards through the history
for msg in reversed(history):
if isinstance(msg, FileResponse):
if msg.data_type == "image":
# Base64 encode the image
msg.data = pil_to_base64(msg.data)
file_responses.append(msg)
if msg.type == "start":
break
response = ChatResponse(
message=result,
intermediate_steps=intermediate_steps.strip(),
type="end",
files=file_responses,
)
await self.send_json(client_id, response)
self.chat_history.add_message(client_id, response)
async def handle_websocket(self, client_id: str, websocket: WebSocket):
await self.connect(client_id, websocket)
try:
chat_history = self.chat_history.get_history(client_id)
# iterate and make BaseModel into dict
chat_history = [chat.dict() for chat in chat_history]
await websocket.send_json(chat_history)
while True:
json_payload = await websocket.receive_json()
try:
payload = json.loads(json_payload)
except TypeError:
payload = json_payload
if "clear_history" in payload:
self.chat_history.history[client_id] = []
continue
with self.cache_manager.set_client_id(client_id):
await self.process_message(client_id, payload)
except Exception as e:
# Handle any exceptions that might occur
logger.exception(e)
# send a message to the client
await self.active_connections[client_id].close(
code=status.WS_1011_INTERNAL_ERROR, reason=str(e)[:120]
)
self.disconnect(client_id)
finally:
try:
connection = self.active_connections.get(client_id)
if connection:
await connection.close(code=1000, reason="Client disconnected")
self.disconnect(client_id)
except Exception as e:
logger.exception(e)
self.disconnect(client_id)
async def process_graph(
graph_data: Dict,
is_first_message: bool,
chat_message: ChatMessage,
websocket: WebSocket,
):
langchain_object = load_or_build_langchain_object(graph_data, is_first_message)
langchain_object = try_setting_streaming_options(langchain_object, websocket)
logger.debug("Loaded langchain object")
if langchain_object is None:
# Raise user facing error
raise ValueError(
"There was an error loading the langchain_object. Please, check all the nodes and try again."
)
# Generate result and thought
try:
logger.debug("Generating result and thought")
result, intermediate_steps = await get_result_and_steps(
langchain_object, chat_message.message or "", websocket=websocket
)
logger.debug("Generated result and intermediate_steps")
return result, intermediate_steps
except Exception as e:
# Log stack trace
logger.exception(e)
raise e