Vald
Vald is a highly scalable distributed fast approximate nearest neighbor (ANN) dense vector search engine.
This notebook shows how to use functionality related to the Vald
database.
To run this notebook you need a running Vald cluster. Check Get Started for more information.
See the installation instructions.
%pip install --upgrade --quiet vald-client-python
Basic Example
from langchain_community.document_loaders import TextLoader
from langchain_community.embeddings import HuggingFaceEmbeddings
from langchain_community.vectorstores import Vald
from langchain_text_splitters import CharacterTextSplitter
raw_documents = TextLoader("state_of_the_union.txt").load()
text_splitter = CharacterTextSplitter(chunk_size=1000, chunk_overlap=0)
documents = text_splitter.split_documents(raw_documents)
embeddings = HuggingFaceEmbeddings()
db = Vald.from_documents(documents, embeddings, host="localhost", port=8080)
API Reference:
query = "What did the president say about Ketanji Brown Jackson"
docs = db.similarity_search(query)
docs[0].page_content
Similarity search by vector
embedding_vector = embeddings.embed_query(query)
docs = db.similarity_search_by_vector(embedding_vector)
docs[0].page_content
Similarity search with score
docs_and_scores = db.similarity_search_with_score(query)
docs_and_scores[0]
Maximal Marginal Relevance Search (MMR)
In addition to using similarity search in the retriever object, you can also use mmr
as retriever.
retriever = db.as_retriever(search_type="mmr")
retriever.invoke(query)
Or use max_marginal_relevance_search
directly:
db.max_marginal_relevance_search(query, k=2, fetch_k=10)
Example of using secure connection
In order to run this notebook, it is necessary to run a Vald cluster with secure connection.
Here is an example of a Vald cluster with the following configuration using Athenz authentication.
ingress(TLS) -> authorization-proxy(Check athenz-role-auth in grpc metadata) -> vald-lb-gateway
import grpc
with open("test_root_cacert.crt", "rb") as root:
credentials = grpc.ssl_channel_credentials(root_certificates=root.read())
# Refresh is required for server use
with open(".ztoken", "rb") as ztoken:
token = ztoken.read().strip()
metadata = [(b"athenz-role-auth", token)]
from langchain_community.document_loaders import TextLoader
from langchain_community.embeddings import HuggingFaceEmbeddings
from langchain_community.vectorstores import Vald
from langchain_text_splitters import CharacterTextSplitter
raw_documents = TextLoader("state_of_the_union.txt").load()
text_splitter = CharacterTextSplitter(chunk_size=1000, chunk_overlap=0)
documents = text_splitter.split_documents(raw_documents)
embeddings = HuggingFaceEmbeddings()
db = Vald.from_documents(
documents,
embeddings,
host="localhost",
port=443,
grpc_use_secure=True,
grpc_credentials=credentials,
grpc_metadata=metadata,
)
API Reference:
query = "What did the president say about Ketanji Brown Jackson"
docs = db.similarity_search(query, grpc_metadata=metadata)
docs[0].page_content
Similarity search by vector
embedding_vector = embeddings.embed_query(query)
docs = db.similarity_search_by_vector(embedding_vector, grpc_metadata=metadata)
docs[0].page_content
Similarity search with score
docs_and_scores = db.similarity_search_with_score(query, grpc_metadata=metadata)
docs_and_scores[0]
Maximal Marginal Relevance Search (MMR)
retriever = db.as_retriever(
search_kwargs={"search_type": "mmr", "grpc_metadata": metadata}
)
retriever.invoke(query, grpc_metadata=metadata)
Or:
db.max_marginal_relevance_search(query, k=2, fetch_k=10, grpc_metadata=metadata)