core[patch]: Fix "argument of type 'NoneType' is not iterable" error in LangChainTracer (#26576)

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---------

Co-authored-by: Erick Friis <erick@langchain.dev>

libs/community/langchain_community/agents/openai_assistant/base.py

@@ -301,7 +301,7 @@ class OpenAIAssistantV2Runnable(OpenAIAssistantRunnable):
             inheritable_metadata=config.get("metadata"),
         )
         run_manager = callback_manager.on_chain_start(
-            dumpd(self), input, name=config.get("run_name")
+            dumpd(self), input, name=config.get("run_name") or self.get_name()
         )
 
         files = _convert_file_ids_into_attachments(kwargs.get("file_ids", []))
@@ -437,7 +437,7 @@ class OpenAIAssistantV2Runnable(OpenAIAssistantRunnable):
             inheritable_metadata=config.get("metadata"),
         )
         run_manager = callback_manager.on_chain_start(
-            dumpd(self), input, name=config.get("run_name")
+            dumpd(self), input, name=config.get("run_name") or self.get_name()
         )
 
         files = _convert_file_ids_into_attachments(kwargs.get("file_ids", []))

libs/community/tests/unit_tests/callbacks/test_callback_manager.py

@@ -121,4 +121,4 @@ def test_callback_manager_configure_context_vars(
                     assert cb.completion_tokens == 1
                     assert cb.total_cost > 0
             wait_for_all_tracers()
-            assert LangChainTracer._persist_run_single.call_count == 1  # type: ignore
+            assert LangChainTracer._persist_run_single.call_count == 4  # type: ignore

libs/core/langchain_core/tracers/schemas.py

@@ -135,11 +135,13 @@ class Run(BaseRunV2):
     @root_validator(pre=True)
     def assign_name(cls, values: dict) -> dict:
         """Assign name to the run."""
-        if values.get("name") is None:
+        if values.get("name") is None and values["serialized"] is not None:
             if "name" in values["serialized"]:
                 values["name"] = values["serialized"]["name"]
             elif "id" in values["serialized"]:
                 values["name"] = values["serialized"]["id"][-1]
+        if values.get("name") is None:
+            values["name"] = "Unnamed"
         if values.get("events") is None:
             values["events"] = []
         return values

libs/langchain/langchain/agents/openai_assistant/base.py

@@ -310,7 +310,7 @@ class OpenAIAssistantRunnable(RunnableSerializable[Dict, OutputType]):
             inheritable_metadata=config.get("metadata"),
         )
         run_manager = callback_manager.on_chain_start(
-            dumpd(self), input, name=config.get("run_name")
+            dumpd(self), input, name=config.get("run_name") or self.get_name()
         )
         try:
             # Being run within AgentExecutor and there are tool outputs to submit.
@@ -429,7 +429,7 @@ class OpenAIAssistantRunnable(RunnableSerializable[Dict, OutputType]):
             inheritable_metadata=config.get("metadata"),
         )
         run_manager = callback_manager.on_chain_start(
-            dumpd(self), input, name=config.get("run_name")
+            dumpd(self), input, name=config.get("run_name") or self.get_name()
         )
         try:
             # Being run within AgentExecutor and there are tool outputs to submit.

libs/langchain/langchain/chains/llm.py

@@ -242,6 +242,7 @@ class LLMChain(Chain):
         run_manager = callback_manager.on_chain_start(
             None,
             {"input_list": input_list},
+            name=self.get_name(),
         )
         try:
             response = self.generate(input_list, run_manager=run_manager)
@@ -262,6 +263,7 @@ class LLMChain(Chain):
         run_manager = await callback_manager.on_chain_start(
             None,
             {"input_list": input_list},
+            name=self.get_name(),
         )
         try:
             response = await self.agenerate(input_list, run_manager=run_manager)