_get_trace_callbacks() — langchain Function Reference

Source Code

libs/core/langchain_core/tracers/context.py lines 105–129

def _get_trace_callbacks(
    project_name: str | None = None,
    example_id: str | UUID | None = None,
    callback_manager: CallbackManager | AsyncCallbackManager | None = None,
) -> Callbacks:
    if _tracing_v2_is_enabled():
        project_name_ = project_name or _get_tracer_project()
        tracer = tracing_v2_callback_var.get() or LangChainTracer(
            project_name=project_name_,
            example_id=example_id,
        )
        if callback_manager is None:
            cb = cast("Callbacks", [tracer])
        else:
            if not any(
                isinstance(handler, LangChainTracer)
                for handler in callback_manager.handlers
            ):
                callback_manager.add_handler(tracer)
                # If it already has a LangChainTracer, we don't need to add another one.
                # this would likely mess up the trace hierarchy.
            cb = callback_manager
    else:
        cb = None
    return cb