26 lines
770 B
Python

from __future__ import annotations
from datetime import timedelta
from typing import Literal
from langgraph.types import TimeoutPolicy
_SYNC_TIMEOUT_PREFIX = (
"Node timeouts are only supported for async nodes because sync Python "
"execution cannot be safely cancelled in-process."
)
def coerce_timeout_policy(
value: float | timedelta | TimeoutPolicy | None,
) -> TimeoutPolicy | None:
"""Normalize a timeout value to positive-second policy fields."""
return TimeoutPolicy.coerce(value)
def sync_timeout_unsupported(
name: str, *, kind: Literal["Node", "Task"] = "Node"
) -> ValueError:
"""Build the canonical error for using `timeout` with a sync target."""
return ValueError(f"{_SYNC_TIMEOUT_PREFIX} {kind} {name!r} is sync.")