langchain/templates/intel-rag-xeon/intel_rag_xeon/chain.py

73 lines
1.9 KiB
Python

from langchain.callbacks import streaming_stdout
from langchain_chroma import Chroma
from langchain_community.embeddings import HuggingFaceEmbeddings
from langchain_community.llms import HuggingFaceEndpoint
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 RunnableParallel, RunnablePassthrough
from langchain_core.vectorstores import VectorStoreRetriever
# Make this look better in the docs.
class Question(BaseModel):
__root__: str
# Init Embeddings
embedder = HuggingFaceEmbeddings(model_name="sentence-transformers/all-MiniLM-L6-v2")
knowledge_base = Chroma(
persist_directory="/tmp/xeon_rag_db",
embedding_function=embedder,
collection_name="xeon-rag",
)
query = "What was Nike's revenue in 2023?"
docs = knowledge_base.similarity_search(query)
print(docs[0].page_content)
retriever = VectorStoreRetriever(
vectorstore=knowledge_base, search_type="mmr", search_kwargs={"k": 1, "fetch_k": 5}
)
# Define our prompt
template = """
Use the following pieces of context from retrieved
dataset to answer the question. Do not make up an answer if there is no
context provided to help answer it.
Context:
---------
{context}
---------
Question: {question}
---------
Answer:
"""
prompt = ChatPromptTemplate.from_template(template)
ENDPOINT_URL = "http://localhost:8080"
callbacks = [streaming_stdout.StreamingStdOutCallbackHandler()]
model = HuggingFaceEndpoint(
endpoint_url=ENDPOINT_URL,
max_new_tokens=512,
top_k=10,
top_p=0.95,
typical_p=0.95,
temperature=0.01,
repetition_penalty=1.03,
streaming=True,
)
# RAG Chain
chain = (
RunnableParallel({"context": retriever, "question": RunnablePassthrough()})
| prompt
| model
| StrOutputParser()
).with_types(input_type=Question)