ModuleNotFoundError: No module named 'langchain.docstore'

[Yugsolanki]

Description:
I encountered a ModuleNotFoundError while working with the BaseRetriever class in the base.py file. The error message indicates that the module langchain.docstore cannot be found, which is causing issues when trying to import necessary components for vector retrieval.

Steps to Reproduce:

1. Attempt to run the code in base.py.
2. Observe the error message: ModuleNotFoundError: No module named 'langchain.docstore'.

Expected Behavior:
The code should run without import errors, allowing for the proper functionality of the BaseRetriever class.

Actual Behavior:
The code fails to execute due to the missing module, preventing any further operations that depend on this class.

Proposed Solution:
Review and update the import statements in base.py to ensure compatibility with the current structure of the langchain library. This may involve checking the latest documentation for langchain and adjusting the imports accordingly.

Additional Information:

• The issue seems to be related to recent changes in the langchain library structure.
• Please let me know if further information is needed to assist in resolving this issue.

[Yugsolanki]

Please add the label: bug

[karanataryn]

+1 facing the same issue

[Yugsolanki]

@changdazhou I have already submitted pull request.

[changdazhou]

Thank you for your submission. Please ensure your code is submitted to the develop branch, and after the code is merged, we will synchronize it to the release branch. Additionally, please confirm whether your changes are forward-compatible. Since PaddleX has locked the version of langchain, if your changes support the latest version, further consideration may be needed regarding compatibility with other dependencies.

[YouLei0106]

“”“
LangChain compatibility patch for paddlex 3.3.12.

This module provides compatibility shims for paddlex 3.3.12 which depends on
old langchain module paths that have been removed in langchain 1.0+.
”“”
import sys
import logging
import types
from typing import Any

logger = logging.getLogger(name)

“”“Try to import the new location first”“”
try:
from langchain_core.documents import Document
_Document = Document
except ImportError:
try:
“”“ Fallback to langchain.schema if langchain_core is not available”“”
from langchain.schema import Document
_Document = Document
except ImportError:
logger.warning(
"Could not import Document from langchain_core.documents or langchain.schema. "
"Compatibility patch may not work correctly."
)
_Document = None

“”“Try to import RecursiveCharacterTextSplitter from new location”“”
try:
from langchain_text_splitters.character import RecursiveCharacterTextSplitter
_RecursiveCharacterTextSplitter = RecursiveCharacterTextSplitter
except ImportError:
try:
“”“ Fallback to langchain.text_splitter if langchain_text_splitters is not available”“”
from langchain.text_splitter import RecursiveCharacterTextSplitter
_RecursiveCharacterTextSplitter = RecursiveCharacterTextSplitter
except ImportError:
logger.warning(
"Could not import RecursiveCharacterTextSplitter from langchain_text_splitters or langchain.text_splitter. "
"Compatibility patch may not work correctly."
)
_RecursiveCharacterTextSplitter = None

def _create_compat_module():
"""Create fake langchain modules for compatibility."""
“”“ Check if already patched”“”
if "langchain.docstore.document" in sys.modules and "langchain.text_splitter" in sys.modules:
logger.debug("Compatibility patch already applied")
return

“”“ Create a fake langchain package if it doesn't exist”“”
if "langchain" not in sys.modules:
    langchain_module = types.ModuleType("langchain")
    sys.modules["langchain"] = langchain_module
else:
    langchain_module = sys.modules["langchain"]

“”“ Create langchain.docstore.document module if Document is available”“”
if _Document is not None:
    if "langchain.docstore.document" not in sys.modules:
        document_module = types.ModuleType("langchain.docstore.document")
        document_module.Document = _Document
        document_module.__all__ = ["Document"]
        sys.modules["langchain.docstore.document"] = document_module

        “”“ Create a fake langchain.docstore package”“” 
        if "langchain.docstore" not in sys.modules:
            docstore_module = types.ModuleType("langchain.docstore")
            docstore_module.document = document_module
            sys.modules["langchain.docstore"] = docstore_module

        “”“ Add docstore to langchain”“” 
        if not hasattr(langchain_module, "docstore"):
            langchain_module.docstore = docstore_module
else:
    logger.warning("Document class not available, skipping docstore patch")

“”“ Create langchain.text_splitter module if RecursiveCharacterTextSplitter is available”“”
if _RecursiveCharacterTextSplitter is not None:
    if "langchain.text_splitter" not in sys.modules:
        text_splitter_module = types.ModuleType("langchain.text_splitter")
        text_splitter_module.RecursiveCharacterTextSplitter = _RecursiveCharacterTextSplitter
        text_splitter_module.__all__ = ["RecursiveCharacterTextSplitter"]
        sys.modules["langchain.text_splitter"] = text_splitter_module

        “”“ Add text_splitter to langchain”“”
        if not hasattr(langchain_module, "text_splitter"):
            langchain_module.text_splitter = text_splitter_module
else:
    logger.warning("RecursiveCharacterTextSplitter not available, skipping text_splitter patch")

logger.info("LangChain compatibility patch applied for paddlex 3.3.12")

def apply_patch():
"""Apply the compatibility patch.

Call this function before importing paddlex to ensure compatibility.
"""
try:
    _create_compat_module()
except Exception as e:
    logger.warning(f"Failed to apply LangChain compatibility patch: {e}")

“”“ Automatically apply the patch when this module is imported”“”

try:
apply_patch()
print("✓ Patch module imported")
except Exception as e:
print(f"✗ Failed to import patch: {e}")

import paddlex