langchain/templates/propositional-retrieval/propositional_retrieval/chain.py
William FH 65091ebe50
Update propositional-retrieval template (#14766)
More descriptive name. Add parser in ingest. Update image link
2023-12-15 07:57:45 -08:00

68 lines
1.8 KiB
Python

from langchain_community.chat_models import ChatOpenAI
from langchain_core.load import load
from langchain_core.output_parsers import StrOutputParser
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.pydantic_v1 import BaseModel
from langchain_core.runnables import RunnablePassthrough
from propositional_retrieval.constants import DOCSTORE_ID_KEY
from propositional_retrieval.storage import get_multi_vector_retriever
def format_docs(docs: list) -> str:
loaded_docs = [load(doc) for doc in docs]
return "\n".join(
[
f"<Document id={i}>\n{doc.page_content}\n</Document>"
for i, doc in enumerate(loaded_docs)
]
)
def rag_chain(retriever):
"""
The RAG chain
:param retriever: A function that retrieves the necessary context for the model.
:return: A chain of functions representing the multi-modal RAG process.
"""
model = ChatOpenAI(temperature=0, model="gpt-4-1106-preview", max_tokens=1024)
prompt = ChatPromptTemplate.from_messages(
[
(
"system",
"You are an AI assistant. Answer based on the retrieved documents:"
"\n<Documents>\n{context}\n</Documents>",
),
("user", "{question}?"),
]
)
# Define the RAG pipeline
chain = (
{
"context": retriever | format_docs,
"question": RunnablePassthrough(),
}
| prompt
| model
| StrOutputParser()
)
return chain
# Create the multi-vector retriever
retriever = get_multi_vector_retriever(DOCSTORE_ID_KEY)
# Create RAG chain
chain = rag_chain(retriever)
# Add typing for input
class Question(BaseModel):
__root__: str
chain = chain.with_types(input_type=Question)