Upgraded to v0.3. Encountering Exception: RunnableSequence' object has no attribute 'get' when instatiating ReduceDocumentsChain

[dubbl-d]

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Example Code

python         reduce_prompt = PromptTemplate.from_template(template=topic_summary_reduce_prompt,
                                                     partial_variables={
                                                         "format_instructions": transcript_summary_parser.get_format_instructions()})

        combine_documents_chain = create_stuff_documents_chain(self.llm, reduce_prompt,
                                                               document_variable_name="topic_summaries")
        reduce_documents_chain = ReduceDocumentsChain(combine_documents_chain=combine_documents_chain,
                                                      collapse_documents_chain=combine_documents_chain,
                                                      token_max=4000, verbose=True
                                                      )

Description

I am trying to get rid of deprecation warnings and one of the things I have to do is replace the StuffDocumentsChain with the preferred create_stuff_documents_chain(...) method. In the code above, I am getting an exception in pydantic validation code that is looking for a get attribute on the RunnableSequence object. I have checked with the 0.3 langchain docs to make sure my dependencies are correct and I don't reference any Pydantic v1 objects anywhere. This exception happens in the ReduceDocumentsChain constructor/init method when it calls pydantic to validate attributes. It isn't clear where or why it is looking to validate a get attribute.

My dependencies and system info are in the section below. Here is the stack trace that I am getting from LangSmith traces:

AttributeError("'RunnableSequence' object has no attribute 'get'") Traceback (most recent call last): File "/Users/dubbled/eng/inference/llm/llm_inferences.py", line 108, in infer_transcript_topic_summary reduce_documents_chain = ReduceDocumentsChain(combine_documents_chain=combine_documents_chain, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/dubbled/.pyenv/versions/3.11.7/lib/python3.11/site-packages/langchain_core/load/serializable.py", line 112, in init super().init(*args, **kwargs) File "/Users/dubbled/.pyenv/versions/3.11.7/lib/python3.11/site-packages/pydantic/main.py", line 212, in init validated_self = self.pydantic_validator.validate_python(data, self_instance=self) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/dubbled/.pyenv/versions/3.11.7/lib/python3.11/site-packages/langchain/chains/base.py", line 236, in raise_callback_manager_deprecation if values.get("callback_manager") is not None: ^^^^^^^^^^ File "/Users/dubbled/.pyenv/versions/3.11.7/lib/python3.11/site-packages/langchain_core/runnables/base.py", line 5704, in getattr attr = getattr(self.bound, name) ^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/dubbled/.pyenv/versions/3.11.7/lib/python3.11/site-packages/pydantic/main.py", line 856, in getattr raise AttributeError(f'{type(self).name!r} object has no attribute {item!r}') AttributeError: 'RunnableSequence' object has no attribute 'get'

System Info

$ python -m langchain_core.sys_info

System Information

OS: Darwin
OS Version: Darwin Kernel Version 23.1.0: Mon Oct 9 21:32:11 PDT 2023; root:xnu-10002.41.9~7/RELEASE_ARM64_T6030
Python Version: 3.11.7 (main, Jan 10 2024, 14:29:12) [Clang 15.0.0 (clang-1500.1.0.2.5)]

Package Information

langchain_core: 0.3.1
langchain: 0.3.0
langsmith: 0.1.122
langchain_cli: 0.0.21
langchain_openai: 0.2.0
langchain_text_splitters: 0.3.0
langchainhub: 0.1.14
langserve: 0.0.41

Optional packages not installed

langgraph

Other Dependencies

aiohttp: 3.9.2
async-timeout: 4.0.3
fastapi: 0.109.2
gitpython: 3.1.43
httpx: 0.26.0
httpx-sse: 0.4.0
jsonpatch: 1.33
langserve[all]: Installed. No version info available.
numpy: 1.26.4
openai: 1.46.0
orjson: 3.9.14
packaging: 23.2
pydantic: 2.9.2
PyYAML: 6.0.1
requests: 2.32.3
SQLAlchemy: 2.0.27
sse-starlette: 1.8.2
tenacity: 8.2.3
tiktoken: 0.7.0
tomlkit: 0.12.4
typer[all]: Installed. No version info available.
types-requests: 2.31.0.20240125
typing-extensions: 4.12.2
uvicorn: 0.23.2

[dosubot[bot]]

The exception "RunnableSequence' object has no attribute 'get'" when instantiating ReduceDocumentsChain in LangChain v0.3 is likely due to the callbacks parameter being passed incorrectly. The callbacks parameter should be of type Callbacks, but it seems that an incorrect type is being passed, which does not have the get attribute.

In the provided code, the callbacks parameter is passed to the LLMChain and StuffDocumentsChain constructors. Ensure that the callbacks parameter is correctly instantiated as a Callbacks object.

Here is a snippet showing the correct usage:

from langchain_core.callbacks import Callbacks

# Assuming you have a valid Callbacks object
callbacks = Callbacks()

reduce_documents_chain = ReduceDocumentsChain(
    combine_documents_chain=combine_documents_chain,
    collapse_documents_chain=combine_documents_chain,
    token_max=4000,
    verbose=True,
    callbacks=callbacks,  # Ensure this is a Callbacks object
)

Make sure that the callbacks parameter is correctly instantiated and passed as shown above.

Additionally, ensure that the combine_documents_chain and collapse_documents_chain are correctly set up. The ReduceDocumentsChain expects these chains to be properly configured, as shown in the example from the LangChain documentation:

from langchain.chains import (
    StuffDocumentsChain,
    LLMChain,
    ReduceDocumentsChain,
    MapReduceDocumentsChain,
)
from langchain_core.prompts import PromptTemplate
from langchain_community.llms import OpenAI

document_prompt = PromptTemplate(
    input_variables=["page_content"],
    template="{page_content}"
)
document_variable_name = "context"
llm = OpenAI()
prompt = PromptTemplate.from_template(
    "Summarize this content: {context}"
)
llm_chain = LLMChain(llm=llm, prompt=prompt)
reduce_prompt = PromptTemplate.from_template(
    "Combine these summaries: {context}"
)
reduce_llm_chain = LLMChain(llm=llm, prompt=reduce_prompt)
combine_documents_chain = StuffDocumentsChain(
    llm_chain=reduce_llm_chain,
    document_prompt=document_prompt,
    document_variable_name=document_variable_name
)
reduce_documents_chain = ReduceDocumentsChain(
    combine_documents_chain=combine_documents_chain,
)
chain = MapReduceDocumentsChain(
    llm_chain=llm_chain,
    reduce_documents_chain=reduce_documents_chain,
)

Ensure that all components are correctly instantiated and passed to avoid attribute errors ^[1][2].

To continue talking to Dosu, mention @dosu.

[eyurtsev]

@dubbl-d please provide a minimal reproducible example. Feel free to open an issue if it's obviously not from user code