From 43cc5fff019808d0c72f5f85424bbdbf8b27fc5d Mon Sep 17 00:00:00 2001 From: Hassieb Pakzad <68423100+hassiebp@users.noreply.github.com> Date: Fri, 27 Jun 2025 14:10:20 +0200 Subject: [PATCH] feat(langchain): add last trace id property to CallbackHandler --- langfuse/langchain/CallbackHandler.py | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/langfuse/langchain/CallbackHandler.py b/langfuse/langchain/CallbackHandler.py index f301dfa4e..9c6a03c78 100644 --- a/langfuse/langchain/CallbackHandler.py +++ b/langfuse/langchain/CallbackHandler.py @@ -63,6 +63,8 @@ def __init__(self, *, public_key: Optional[str] = None) -> None: self.prompt_to_parent_run_map: Dict[UUID, Any] = {} self.updated_completion_start_time_memo: Set[UUID] = set() + self.last_trace_id = None + def on_llm_new_token( self, token: str, @@ -187,6 +189,8 @@ def on_chain_start( level=span_level, ) + self.last_trace_id = self.runs[run_id].trace_id + except Exception as e: langfuse_logger.exception(e) @@ -573,6 +577,8 @@ def __on_llm_action( else: self.runs[run_id] = self.client.start_generation(**content) + self.last_trace_id = self.runs[run_id].trace_id + except Exception as e: langfuse_logger.exception(e)