Use serialized format for messages in tracer (#6827)

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langchain/callbacks/tracers/base.py

@@ -4,12 +4,14 @@ from __future__ import annotations
 import logging
 from abc import ABC, abstractmethod
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Sequence, Union
+from typing import Any, Dict, List, Optional, Sequence, Union, cast
 from uuid import UUID
 
 from langchain.callbacks.base import BaseCallbackHandler
 from langchain.callbacks.tracers.schemas import Run, RunTypeEnum
-from langchain.schema import Document, LLMResult
+from langchain.load.dump import dumpd
+from langchain.schema.document import Document
+from langchain.schema.output import ChatGeneration, LLMResult
 
 logger = logging.getLogger(__name__)
 
@@ -143,6 +145,13 @@ class BaseTracer(BaseCallbackHandler, ABC):
         if llm_run is None or llm_run.run_type != RunTypeEnum.llm:
             raise TracerException("No LLM Run found to be traced")
         llm_run.outputs = response.dict()
+        for i, generations in enumerate(response.generations):
+            for j, generation in enumerate(generations):
+                output_generation = llm_run.outputs["generations"][i][j]
+                if "message" in output_generation:
+                    output_generation["message"] = dumpd(
+                        cast(ChatGeneration, generation).message
+                    )
         llm_run.end_time = datetime.utcnow()
         llm_run.events.append({"name": "end", "time": llm_run.end_time})
         self._end_trace(llm_run)

langchain/callbacks/tracers/langchain.py

@@ -11,13 +11,10 @@ from uuid import UUID
 from langchainplus_sdk import LangChainPlusClient
 
 from langchain.callbacks.tracers.base import BaseTracer
-from langchain.callbacks.tracers.schemas import (
+from langchain.callbacks.tracers.schemas import Run, RunTypeEnum, TracerSession
-    Run,
-    RunTypeEnum,
-    TracerSession,
-)
 from langchain.env import get_runtime_environment
-from langchain.schema.messages import BaseMessage, messages_to_dict
+from langchain.load.dump import dumpd
+from langchain.schema.messages import BaseMessage
 
 logger = logging.getLogger(__name__)
 _LOGGED = set()
@@ -83,7 +80,7 @@ class LangChainTracer(BaseTracer):
             id=run_id,
             parent_run_id=parent_run_id,
             serialized=serialized,
-            inputs={"messages": [messages_to_dict(batch) for batch in messages]},
+            inputs={"messages": [[dumpd(msg) for msg in batch] for batch in messages]},
             extra=kwargs,
             events=[{"name": "start", "time": start_time}],
             start_time=start_time,

tests/integration_tests/llms/test_openai.py

@@ -15,8 +15,8 @@ from tests.unit_tests.callbacks.fake_callback_handler import FakeCallbackHandler
 
 def test_openai_call() -> None:
     """Test valid call to openai."""
-    llm = OpenAI(max_tokens=10)
+    llm = OpenAI(max_tokens=10, n=3)
-    output = llm("Say foo:")
+    output = llm("Say something nice:")
     assert isinstance(output, str)