from langchain.vectorstores.weaviate import Weaviate
from langchain.llms import OpenAI
from langchain.chains import ChatVectorDBChain,ConversationalRetrievalChain,RetrievalQAWithSourcesChain,RetrievalQA
import weaviate
from langchain.prompts.prompt import PromptTemplate
# API Key needs to be passed in playground
OPEN_API_KEY="sk-"
# Connect to Weaviate server - API Key needs to be passed in playground
auth_config = weaviate.auth.AuthApiKey(
api_key="api_key")
client = weaviate.Client(
url="https://abc.weaviate.network",
auth_client_secret=auth_config,
additional_headers={
"X-OpenAI-Api-Key": OPEN_API_KEY
}
)
vectorstore = Weaviate(client, "Products", "description")
llm = OpenAI(model_name="text-davinci-003", temperature=0,
max_tokens=200, openai_api_key=OPEN_API_KEY)
template = """
Return product and price information
--------------------
{summaries}
"""
prompt = PromptTemplate(
input_variables=["summaries"],
template=template,
)
chain = RetrievalQAWithSourcesChain.from_chain_type(llm=llm, retriever=vectorstore.as_retriever(),
return_source_documents=False,
chain_type_kwargs = {"prompt": prompt}
)
result = chain("top rated watches", return_only_outputs=True)
print(result)
raise ValueError(f"Error during query: {result['errors']}")
ValueError: Error during query: [{'locations': [{'column': 24, 'line': 1}], 'message': 'Unknown argument "nearText" on field "Products" of type "GetObjectsObj". Did you mean "nearVector" or "nearObject"?', 'path': None}]
Tried various Chain Methods like
ChatVectorDBChain,ConversationalRetrievalChain,RetrievalQAWithSourcesChain,RetrievalQA
Update (May/2023)
If using weaviate with langchain, it is now not necessary to configure weaviate to use a vectorizer as langchain will take care of it.
Original answer below:
If you're getting this error - that means that Weaviate is getting a text input but it doesn't have a vectorizer set up to convert that input to a vector. So it can't perform a vector search.
ValueError: Error during query: [{'locations': [{'column': 24, 'line': 1}], 'message': 'Unknown argument "nearText" on field "Products" of type "GetObjectsObj". Did you mean "nearVector" or "nearObject"?', 'path': None}]
If you're using a WCS instance, it should have the text2vec-openai module enabled, but I would ask you to check if you've set it up as the vectorizer in the schema.
See, for example, how to do so here: https://weaviate.io/developers/weaviate/configuration/schema-configuration#specify-a-vectorizer