fix: switch langchain imports to core

Author: jan-kubica

langfuse/callback/langchain.py

@@ -5,8 +5,8 @@
 
 import pydantic
 
-try:  # Test that langchain is installed before proceeding
-    import langchain  # noqa
+try:  # Test that langchain core is installed before proceeding
+    import langchain_core  # noqa
 except ImportError as e:
     log = logging.getLogger("langfuse")
     log.error(
@@ -24,11 +24,11 @@
 from langfuse.utils.base_callback_handler import LangfuseBaseCallbackHandler
 
 try:
-    from langchain.callbacks.base import (
+    from langchain_core.callbacks.base import (
         BaseCallbackHandler as LangchainBaseCallbackHandler,
     )
-    from langchain.schema.agent import AgentAction, AgentFinish
-    from langchain.schema.document import Document
+    from langchain_core.agents import AgentAction, AgentFinish
+    from langchain_core.documents import Document
     from langchain_core.outputs import (
         ChatGeneration,
         LLMResult,
@@ -44,7 +44,8 @@
     )
 except ImportError:
     raise ModuleNotFoundError(
-        "Please install langchain to use the Langfuse langchain integration: 'pip install langchain'"
+        "Please install 'langchain core' to use the Langfuse langchain integration:"
+        " 'pip install langchain-core'"
     )
 
 

langfuse/serializer.py

@@ -15,7 +15,7 @@
 
 # Attempt to import Serializable
 try:
-    from langchain.load.serializable import Serializable
+    from langchain_core.load.serializable import Serializable
 except ImportError:
     # If Serializable is not available, set it to NoneType
     Serializable = type(None)

poetry.lock

@@ -13,7 +13,7 @@ pydantic = ">=1.10.7, <3.0"
 backoff = ">=1.10.0"
 openai = { version = ">=0.27.8", optional = true }
 wrapt = "^1.14"
-langchain = { version = ">=0.0.309", optional = true }
+langchain-core = { version = ">=0.2.0", optional = true }
 llama-index = {version = ">=0.10.12, <2.0.0", optional = true}
 packaging = "^23.2"
 idna = "^3.7"
@@ -48,13 +48,16 @@ bson = "^0.5.10"
 langchain-anthropic = "^0.1.4"
 langchain-groq = "^0.1.3"
 langchain-aws = "^0.1.3"
+langchain = "^0.2.9"
+langchain-cohere = "^0.1.9"
+langchain-community = "^0.2.7"
 
 [tool.poetry.group.docs.dependencies]
 pdoc = "^14.4.0"
 
 [tool.poetry.extras]
 openai = ["openai"]
-langchain = ["langchain"]
+langchain = ["langchain-core"]
 llama-index = ["llama-index"]
 
 [build-system]
@@ -67,4 +70,4 @@ log_cli = true
 [tool.poetry_bumpversion.file."langfuse/version.py"]
 
 [tool.poetry.scripts]
-release = "scripts.release:main"
+release = "scripts.release:main"

pyproject.toml

@@ -4,7 +4,7 @@
 from concurrent.futures import ThreadPoolExecutor
 import pytest
 
-from langchain_community.chat_models import ChatOpenAI
+from langchain_openai import ChatOpenAI
 from langchain.prompts import ChatPromptTemplate
 from langfuse.openai import AsyncOpenAI
 from langfuse.decorators import langfuse_context, observe

tests/test_decorators.py

@@ -1401,7 +1401,7 @@ def test_aws_bedrock_chain():
     import os
 
     import boto3
-    from langchain.llms.bedrock import Bedrock
+    from langchain_aws import Bedrock
 
     api_wrapper = LangfuseAPI()
     handler = CallbackHandler(debug=False)

tests/test_langchain.py

@@ -1,6 +1,6 @@
 from langchain_openai import ChatOpenAI, OpenAI
-from langchain.prompts import ChatPromptTemplate, PromptTemplate
-from langchain.schema import StrOutputParser
+from langchain_core.prompts import ChatPromptTemplate, PromptTemplate
+from langchain_core.output_parsers import StrOutputParser
 import pytest
 import types
 from langfuse.callback import CallbackHandler