ConfigError: field "client" not yet prepared so type is still a ForwardRef-FlashrankRerank

[mdeniz1]

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Example Code

from langchain.retrievers import ContextualCompressionRetriever
from langchain.retrievers.document_compressors import FlashrankRerank
compressor = FlashrankRerank()

compression_retriever = ContextualCompressionRetriever(
    base_compressor=compressor, base_retriever=retriever, top_n=4
)

Description

Hi,

I am trying to use FlashrankRerank and I get the following error:

ConfigError: field "client" not yet prepared so type is still a ForwardRef, you might need to call FlashrankRerank.update_forward_refs().

I added this line FlashrankRerank.update_forward_refs() but I still get the error.

System Info

System Information

OS: Darwin
OS Version: Darwin Kernel Version 23.4.0: Fri Mar 15 00:12:49 PDT 2024; root:xnu-10063.101.17~1/RELEASE_ARM64_T6020
Python Version: 3.10.11 (v3.10.11:7d4cc5aa85, Apr 4 2023, 19:05:19) [Clang 13.0.0 (clang-1300.0.29.30)]

Package Information

langchain_core: 0.2.4
langchain: 0.2.2
langchain_community: 0.2.2
langsmith: 0.1.71
langchain_chroma: 0.1.1
langchain_openai: 0.1.8
langchain_text_splitters: 0.2.1

[dosubot[bot]]

Hello, @mdeniz1! I'm here to assist you with your issue. I'm a bot designed to help you solve bugs, answer questions, and become a contributor. Let's work together to resolve the issue you're facing.

To resolve the ConfigError: field "client" not yet prepared so type is still a ForwardRef error when using the FlashrankRerank class, you need to call the update_forward_refs method on the FlashrankRerank class. This method resolves any forward references in the type annotations.

Here is how you can do it:

from langchain.retrievers.document_compressors import FlashrankRerank

# Call update_forward_refs to resolve forward references
FlashrankRerank.update_forward_refs()

Ensure that you call this method after the class definition and before you instantiate or use the FlashrankRerank class. Additionally, make sure that the flashrank package is installed in your environment:

pip install flashrank

Here is an example of how to integrate it into your code:

from langchain.retrievers import ContextualCompressionRetriever
from langchain.retrievers.document_compressors import FlashrankRerank

# Call update_forward_refs to resolve forward references
FlashrankRerank.update_forward_refs()

compressor = FlashrankRerank()
compression_retriever = ContextualCompressionRetriever(
    base_compressor=compressor, base_retriever=retriever, top_n=4
)

This should resolve the ConfigError by ensuring that all forward references are properly updated ^[1][2].

To continue talking to Dosu, mention @dosu.

[dosubot[bot]]

To resolve the NameError: name 'Ranker' is not defined error, ensure that the flashrank package is installed in your environment. The Ranker class is imported from the flashrank package, and if this package is not installed, the import will fail, leading to the NameError.

You can install the flashrank package using pip:

pip install flashrank

Additionally, ensure that the import statements for Ranker and RerankRequest are correctly handled. Here is an example of how to handle the imports and call update_forward_refs:

from langchain.retrievers import ContextualCompressionRetriever
from langchain.retrievers.document_compressors import FlashrankRerank

# Ensure flashrank is installed
try:
    from flashrank import Ranker, RerankRequest
except ImportError:
    raise ImportError(
        "Could not import flashrank python package. "
        "Please install it with `pip install flashrank`."
    )

# Call update_forward_refs to resolve forward references
FlashrankRerank.update_forward_refs()

compressor = FlashrankRerank()
compression_retriever = ContextualCompressionRetriever(
    base_compressor=compressor, base_retriever=retriever, top_n=4
)

This should resolve the NameError by ensuring that the flashrank package is installed and the imports are correctly handled ^[1][2].

To continue talking to Dosu, mention @dosu.

[edsml-nb1623]

Hey, I have the same issue and couldn't get it resolved yet. Did this or any other approach work for you?

[mdeniz1]

no. it did not. I started using cohere rerank. I believe there is a bug in the source code

[edsml-nb1623]

I'm sure you already tried this but for me just restarting the kernel actually did the job

[KiranAkram]

restarting kernel worked for me as well!