register_configure_hook() — langchain Function Reference

Architecture documentation for the register_configure_hook() function in context.py from the langchain codebase.

Function python Observability Tracers

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Observability→ Tracers→ register_configure_hook() — langchain Function Reference

Dependency Diagram

graph TD
  fa70a195_3653_2b1c_77c7_0a133d4c63ea["register_configure_hook()"]
  b631c948_af4b_1ae8_be2d_c334ff40ecef["context.py"]
  fa70a195_3653_2b1c_77c7_0a133d4c63ea -->|defined in| b631c948_af4b_1ae8_be2d_c334ff40ecef
  style fa70a195_3653_2b1c_77c7_0a133d4c63ea fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/core/langchain_core/tracers/context.py lines 171–202

def register_configure_hook(
    context_var: ContextVar[Any | None],
    inheritable: bool,  # noqa: FBT001
    handle_class: type[BaseCallbackHandler] | None = None,
    env_var: str | None = None,
) -> None:
    """Register a configure hook.

    Args:
        context_var: The context variable.
        inheritable: Whether the context variable is inheritable.
        handle_class: The callback handler class.
        env_var: The environment variable.

    Raises:
        ValueError: If `env_var` is set, `handle_class` must also be set to a non-`None`
            value.
    """
    if env_var is not None and handle_class is None:
        msg = "If env_var is set, handle_class must also be set to a non-None value."
        raise ValueError(msg)

    _configure_hooks.append(
        (
            # the typings of ContextVar do not have the generic arg set as covariant
            # so we have to cast it
            cast("ContextVar[BaseCallbackHandler | None]", context_var),
            inheritable,
            handle_class,
            env_var,
        )
    )