Allow astream_log to be used inside atrace_as_chain_group (#12558)

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libs/langchain/langchain/callbacks/manager.py

@@ -1832,6 +1832,18 @@ class AsyncCallbackManagerForChainGroup(AsyncCallbackManager):
         self.parent_run_manager = parent_run_manager
         self.ended = False
 
+    def copy(self) -> AsyncCallbackManagerForChainGroup:
+        return self.__class__(
+            handlers=self.handlers,
+            inheritable_handlers=self.inheritable_handlers,
+            parent_run_id=self.parent_run_id,
+            tags=self.tags,
+            inheritable_tags=self.inheritable_tags,
+            metadata=self.metadata,
+            inheritable_metadata=self.inheritable_metadata,
+            parent_run_manager=self.parent_run_manager,
+        )
+
     async def on_chain_end(
         self, outputs: Union[Dict[str, Any], Any], **kwargs: Any
     ) -> None:

libs/langchain/langchain/callbacks/tracers/log_stream.py

@@ -157,12 +157,13 @@ class LogStreamCallbackHandler(BaseTracer):
         self.receive_stream = receive_stream
         self._key_map_by_run_id: Dict[UUID, str] = {}
         self._counter_map_by_name: Dict[str, int] = defaultdict(int)
+        self.root_id: Optional[UUID] = None
 
     def __aiter__(self) -> AsyncIterator[RunLogPatch]:
         return self.receive_stream.__aiter__()
 
     def include_run(self, run: Run) -> bool:
-        if run.parent_run_id is None:
+        if run.id == self.root_id:
             return False
 
         run_tags = run.tags or []
@@ -199,7 +200,8 @@ class LogStreamCallbackHandler(BaseTracer):
 
     def _on_run_create(self, run: Run) -> None:
         """Start a run."""
-        if run.parent_run_id is None:
+        if self.root_id is None:
+            self.root_id = run.id
             self.send_stream.send_nowait(
                 RunLogPatch(
                     {
@@ -273,7 +275,7 @@ class LogStreamCallbackHandler(BaseTracer):
                 )
             )
         finally:
-            if run.parent_run_id is None:
+            if run.id == self.root_id:
                 self.send_stream.send_nowait(
                     RunLogPatch(
                         {

libs/langchain/langchain/schema/runnable/base.py

@@ -463,7 +463,7 @@ class Runnable(Generic[Input, Output], ABC):
             config["callbacks"] = callbacks + [stream]
         elif isinstance(callbacks, BaseCallbackManager):
             callbacks = callbacks.copy()
-            callbacks.inheritable_handlers.append(stream)
+            callbacks.add_handler(stream, inherit=True)
             config["callbacks"] = callbacks
         else:
             raise ValueError(

libs/langchain/tests/unit_tests/schema/runnable/test_runnable.py

@@ -19,7 +19,7 @@ from freezegun import freeze_time
 from pytest_mock import MockerFixture
 from syrupy import SnapshotAssertion
 
-from langchain.callbacks.manager import Callbacks, collect_runs
+from langchain.callbacks.manager import Callbacks, atrace_as_chain_group, collect_runs
 from langchain.callbacks.tracers.base import BaseTracer
 from langchain.callbacks.tracers.log_stream import RunLog, RunLogPatch
 from langchain.callbacks.tracers.schemas import Run
@@ -1442,6 +1442,40 @@ async def test_prompt() -> None:
         },
     )
 
+    # nested inside trace_with_chain_group
+
+    async with atrace_as_chain_group("a_group") as manager:
+        stream_log_nested = [
+            part
+            async for part in prompt.astream_log(
+                {"question": "What is your name?"}, config={"callbacks": manager}
+            )
+        ]
+
+    assert len(stream_log_nested[0].ops) == 1
+    assert stream_log_nested[0].ops[0]["op"] == "replace"
+    assert stream_log_nested[0].ops[0]["path"] == ""
+    assert stream_log_nested[0].ops[0]["value"]["logs"] == {}
+    assert stream_log_nested[0].ops[0]["value"]["final_output"] is None
+    assert stream_log_nested[0].ops[0]["value"]["streamed_output"] == []
+    assert isinstance(stream_log_nested[0].ops[0]["value"]["id"], str)
+
+    assert stream_log_nested[1:] == [
+        RunLogPatch(
+            {
+                "op": "replace",
+                "path": "/final_output",
+                "value": ChatPromptValue(
+                    messages=[
+                        SystemMessage(content="You are a nice assistant."),
+                        HumanMessage(content="What is your name?"),
+                    ]
+                ),
+            }
+        ),
+        RunLogPatch({"op": "add", "path": "/streamed_output/-", "value": expected}),
+    ]
+
 
 def test_prompt_template_params() -> None:
     prompt = ChatPromptTemplate.from_template(