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.
82 lines
2.5 KiB
Python
82 lines
2.5 KiB
Python
"""Callback handlers that allow listening to events in LangChain."""
|
|
import os
|
|
from contextlib import contextmanager
|
|
from typing import Generator, Optional
|
|
|
|
from langchain.callbacks.aim_callback import AimCallbackHandler
|
|
from langchain.callbacks.base import (
|
|
BaseCallbackHandler,
|
|
BaseCallbackManager,
|
|
CallbackManager,
|
|
)
|
|
from langchain.callbacks.openai_info import OpenAICallbackHandler
|
|
from langchain.callbacks.shared import SharedCallbackManager
|
|
from langchain.callbacks.stdout import StdOutCallbackHandler
|
|
from langchain.callbacks.tracers import SharedLangChainTracer
|
|
from langchain.callbacks.wandb_callback import WandbCallbackHandler
|
|
|
|
|
|
def get_callback_manager() -> BaseCallbackManager:
|
|
"""Return the shared callback manager."""
|
|
return SharedCallbackManager()
|
|
|
|
|
|
def set_handler(handler: BaseCallbackHandler) -> None:
|
|
"""Set handler."""
|
|
callback = get_callback_manager()
|
|
callback.set_handler(handler)
|
|
|
|
|
|
def set_default_callback_manager() -> None:
|
|
"""Set default callback manager."""
|
|
default_handler = os.environ.get("LANGCHAIN_HANDLER", "stdout")
|
|
if default_handler == "stdout":
|
|
set_handler(StdOutCallbackHandler())
|
|
elif default_handler == "langchain":
|
|
session = os.environ.get("LANGCHAIN_SESSION")
|
|
set_tracing_callback_manager(session)
|
|
else:
|
|
raise ValueError(
|
|
f"LANGCHAIN_HANDLER should be one of `stdout` "
|
|
f"or `langchain`, got {default_handler}"
|
|
)
|
|
|
|
|
|
def set_tracing_callback_manager(session_name: Optional[str] = None) -> None:
|
|
"""Set tracing callback manager."""
|
|
handler = SharedLangChainTracer()
|
|
callback = get_callback_manager()
|
|
callback.set_handlers([handler, StdOutCallbackHandler()])
|
|
if session_name is None:
|
|
handler.load_default_session()
|
|
else:
|
|
try:
|
|
handler.load_session(session_name)
|
|
except Exception:
|
|
raise ValueError(f"session {session_name} not found")
|
|
|
|
|
|
@contextmanager
|
|
def get_openai_callback() -> Generator[OpenAICallbackHandler, None, None]:
|
|
"""Get OpenAI callback handler in a context manager."""
|
|
handler = OpenAICallbackHandler()
|
|
manager = get_callback_manager()
|
|
manager.add_handler(handler)
|
|
yield handler
|
|
manager.remove_handler(handler)
|
|
|
|
|
|
__all__ = [
|
|
"CallbackManager",
|
|
"OpenAICallbackHandler",
|
|
"SharedCallbackManager",
|
|
"StdOutCallbackHandler",
|
|
"AimCallbackHandler",
|
|
"WandbCallbackHandler",
|
|
"get_openai_callback",
|
|
"set_tracing_callback_manager",
|
|
"set_default_callback_manager",
|
|
"set_handler",
|
|
"get_callback_manager",
|
|
]
|