Copy core context in RunnableCallable (#973)

libs/langgraph/langgraph/utils.py

@@ -22,6 +22,14 @@ from langchain_core.runnables.graph import Edge, Graph, Node, is_uuid
 from langchain_core.runnables.utils import accepts_config
 from typing_extensions import TypeGuard
 
+try:
+    from langchain_core.runnables.config import _set_config_context
+except ImportError:
+    # For forwards compatibility
+    def _set_config_context(context: RunnableConfig) -> None:  # type: ignore
+        """Set the context for the current thread."""
+        var_child_runnable_config.set(context)
+
 
 # Before Python 3.11 native StrEnum is not available
 class StrEnum(str, enum.Enum):
@@ -89,7 +97,7 @@ class RunnableCallable(Runnable):
         else:
             config = merge_configs(self.config, config)
             context = copy_context()
-            context.run(var_child_runnable_config.set, config)
+            context.run(_set_config_context, config)
             if accepts_config(self.func):
                 kwargs["config"] = config
             ret = context.run(self.func, input, **kwargs)
@@ -110,7 +118,7 @@ class RunnableCallable(Runnable):
         else:
             config = merge_configs(self.config, config)
             context = copy_context()
-            context.run(var_child_runnable_config.set, config)
+            context.run(_set_config_context, config)
             if accepts_config(self.afunc):
                 kwargs["config"] = config
             if sys.version_info >= (3, 11):

libs/langgraph/tests/test_utils.py

@@ -1,5 +1,14 @@
 import functools
+import sys
+import uuid
+from typing import TypedDict
+from unittest.mock import patch
 
+import langsmith
+import pytest
+
+from langgraph.graph import END, StateGraph
+from langgraph.graph.graph import CompiledGraph
 from langgraph.utils import is_async_callable, is_async_generator
 
 
@@ -70,3 +79,43 @@ def test_is_generator() -> None:
     assert not is_async_generator(sync_runnable)
     wrapped_sync_runnable = functools.wraps(sync_runnable)(sync_runnable)
     assert not is_async_generator(wrapped_sync_runnable)
+
+
+@pytest.fixture
+def rt_graph() -> CompiledGraph:
+    class State(TypedDict):
+        foo: int
+        node_run_id: int
+
+    def node(_: State):
+        from langsmith import get_current_run_tree  # type: ignore
+
+        return {"node_run_id": get_current_run_tree().id}  # type: ignore
+
+    graph = StateGraph(State)
+    graph.add_node(node)
+    graph.set_entry_point("node")
+    graph.add_edge("node", END)
+    return graph.compile()
+
+
+def test_runnable_callable_tracing_nested(rt_graph: CompiledGraph) -> None:
+    with patch("langsmith.client.Client", spec=langsmith.Client) as mock_client:
+        with patch("langchain_core.tracers.langchain.get_client") as mock_get_client:
+            mock_get_client.return_value = mock_client
+            with langsmith.tracing_context(enabled=True):
+                res = rt_graph.invoke({"foo": 1})
+    assert isinstance(res["node_run_id"], uuid.UUID)
+
+
+@pytest.mark.skipif(
+    sys.version_info < (3, 11),
+    reason="Python 3.11+ is required for async contextvars support",
+)
+async def test_runnable_callable_tracing_nested_async(rt_graph: CompiledGraph) -> None:
+    with patch("langsmith.client.Client", spec=langsmith.Client) as mock_client:
+        with patch("langchain_core.tracers.langchain.get_client") as mock_get_client:
+            mock_get_client.return_value = mock_client
+            with langsmith.tracing_context(enabled=True):
+                res = await rt_graph.ainvoke({"foo": 1})
+    assert isinstance(res["node_run_id"], uuid.UUID)