id
stringlengths 14
16
| text
stringlengths 44
2.73k
| source
stringlengths 49
114
|
|---|---|---|
1ae7f74e8fd6-6
|
2. Initializes the Qdrant database as an in-memory docstore by default
(and overridable to a remote docstore)
3. Adds the text embeddings to the Qdrant database
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import Qdrant
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
qdrant = Qdrant.from_texts(texts, embeddings, "localhost")
"""
try:
import qdrant_client
except ImportError:
raise ValueError(
"Could not import qdrant-client python package. "
"Please install it with `pip install qdrant-client`."
)
from qdrant_client.http import models as rest
# Just do a single quick embedding to get vector size
partial_embeddings = embedding.embed_documents(texts[:1])
vector_size = len(partial_embeddings[0])
collection_name = collection_name or uuid.uuid4().hex
distance_func = distance_func.upper()
client = qdrant_client.QdrantClient(
location=location,
url=url,
port=port,
grpc_port=grpc_port,
prefer_grpc=prefer_grpc,
https=https,
api_key=api_key,
prefix=prefix,
timeout=timeout,
host=host,
path=path,
**kwargs,
)
client.recreate_collection(
collection_name=collection_name,
vectors_config=rest.VectorParams(
size=vector_size,
distance=rest.Distance[distance_func],
),
)
# Now generate the embeddings for all the texts
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/qdrant.html
|
1ae7f74e8fd6-7
|
),
)
# Now generate the embeddings for all the texts
embeddings = embedding.embed_documents(texts)
client.upsert(
collection_name=collection_name,
points=rest.Batch.construct(
ids=[md5(text.encode("utf-8")).hexdigest() for text in texts],
vectors=embeddings,
payloads=cls._build_payloads(
texts, metadatas, content_payload_key, metadata_payload_key
),
),
)
return cls(
client=client,
collection_name=collection_name,
embedding_function=embedding.embed_query,
content_payload_key=content_payload_key,
metadata_payload_key=metadata_payload_key,
)
@classmethod
def _build_payloads(
cls,
texts: Iterable[str],
metadatas: Optional[List[dict]],
content_payload_key: str,
metadata_payload_key: str,
) -> List[dict]:
payloads = []
for i, text in enumerate(texts):
if text is None:
raise ValueError(
"At least one of the texts is None. Please remove it before "
"calling .from_texts or .add_texts on Qdrant instance."
)
metadata = metadatas[i] if metadatas is not None else None
payloads.append(
{
content_payload_key: text,
metadata_payload_key: metadata,
}
)
return payloads
@classmethod
def _document_from_scored_point(
cls,
scored_point: Any,
content_payload_key: str,
metadata_payload_key: str,
) -> Document:
return Document(
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/qdrant.html
|
1ae7f74e8fd6-8
|
metadata_payload_key: str,
) -> Document:
return Document(
page_content=scored_point.payload.get(content_payload_key),
metadata=scored_point.payload.get(metadata_payload_key) or {},
)
def _qdrant_filter_from_dict(self, filter: Optional[MetadataFilter]) -> Any:
if filter is None or 0 == len(filter):
return None
from qdrant_client.http import models as rest
return rest.Filter(
must=[
rest.FieldCondition(
key=f"{self.metadata_payload_key}.{key}",
match=rest.MatchValue(value=value),
)
for key, value in filter.items()
]
)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/qdrant.html
|
95f2afed514f-0
|
Source code for langchain.vectorstores.supabase
from __future__ import annotations
from itertools import repeat
from typing import (
TYPE_CHECKING,
Any,
Iterable,
List,
Optional,
Tuple,
Type,
Union,
)
import numpy as np
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
from langchain.vectorstores.utils import maximal_marginal_relevance
if TYPE_CHECKING:
import supabase
[docs]class SupabaseVectorStore(VectorStore):
"""VectorStore for a Supabase postgres database. Assumes you have the `pgvector`
extension installed and a `match_documents` (or similar) function. For more details:
https://js.langchain.com/docs/modules/indexes/vector_stores/integrations/supabase
You can implement your own `match_documents` function in order to limit the search
space to a subset of documents based on your own authorization or business logic.
Note that the Supabase Python client does not yet support async operations.
If you'd like to use `max_marginal_relevance_search`, please review the instructions
below on modifying the `match_documents` function to return matched embeddings.
"""
_client: supabase.client.Client
# This is the embedding function. Don't confuse with the embedding vectors.
# We should perhaps rename the underlying Embedding base class to EmbeddingFunction
# or something
_embedding: Embeddings
table_name: str
query_name: str
def __init__(
self,
client: supabase.client.Client,
embedding: Embeddings,
table_name: str,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-1
|
embedding: Embeddings,
table_name: str,
query_name: Union[str, None] = None,
) -> None:
"""Initialize with supabase client."""
try:
import supabase # noqa: F401
except ImportError:
raise ValueError(
"Could not import supabase python package. "
"Please install it with `pip install supabase`."
)
self._client = client
self._embedding: Embeddings = embedding
self.table_name = table_name or "documents"
self.query_name = query_name or "match_documents"
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict[Any, Any]]] = None,
**kwargs: Any,
) -> List[str]:
docs = self._texts_to_documents(texts, metadatas)
vectors = self._embedding.embed_documents(list(texts))
return self.add_vectors(vectors, docs)
[docs] @classmethod
def from_texts(
cls: Type["SupabaseVectorStore"],
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
client: Optional[supabase.client.Client] = None,
table_name: Optional[str] = "documents",
query_name: Union[str, None] = "match_documents",
**kwargs: Any,
) -> "SupabaseVectorStore":
"""Return VectorStore initialized from texts and embeddings."""
if not client:
raise ValueError("Supabase client is required.")
if not table_name:
raise ValueError("Supabase document table_name is required.")
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-2
|
if not table_name:
raise ValueError("Supabase document table_name is required.")
embeddings = embedding.embed_documents(texts)
docs = cls._texts_to_documents(texts, metadatas)
_ids = cls._add_vectors(client, table_name, embeddings, docs)
return cls(
client=client,
embedding=embedding,
table_name=table_name,
query_name=query_name,
)
[docs] def add_vectors(
self, vectors: List[List[float]], documents: List[Document]
) -> List[str]:
return self._add_vectors(self._client, self.table_name, vectors, documents)
[docs] def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
vectors = self._embedding.embed_documents([query])
return self.similarity_search_by_vector(vectors[0], k)
[docs] def similarity_search_by_vector(
self, embedding: List[float], k: int = 4, **kwargs: Any
) -> List[Document]:
result = self.similarity_search_by_vector_with_relevance_scores(embedding, k)
documents = [doc for doc, _ in result]
return documents
[docs] def similarity_search_with_relevance_scores(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Tuple[Document, float]]:
vectors = self._embedding.embed_documents([query])
return self.similarity_search_by_vector_with_relevance_scores(vectors[0], k)
[docs] def similarity_search_by_vector_with_relevance_scores(
self, query: List[float], k: int
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-3
|
self, query: List[float], k: int
) -> List[Tuple[Document, float]]:
match_documents_params = dict(query_embedding=query, match_count=k)
res = self._client.rpc(self.query_name, match_documents_params).execute()
match_result = [
(
Document(
metadata=search.get("metadata", {}), # type: ignore
page_content=search.get("content", ""),
),
search.get("similarity", 0.0),
)
for search in res.data
if search.get("content")
]
return match_result
[docs] def similarity_search_by_vector_returning_embeddings(
self, query: List[float], k: int
) -> List[Tuple[Document, float, np.ndarray[np.float32, Any]]]:
match_documents_params = dict(query_embedding=query, match_count=k)
res = self._client.rpc(self.query_name, match_documents_params).execute()
match_result = [
(
Document(
metadata=search.get("metadata", {}), # type: ignore
page_content=search.get("content", ""),
),
search.get("similarity", 0.0),
# Supabase returns a vector type as its string represation (!).
# This is a hack to convert the string to numpy array.
np.fromstring(
search.get("embedding", "").strip("[]"), np.float32, sep=","
),
)
for search in res.data
if search.get("content")
]
return match_result
@staticmethod
def _texts_to_documents(
texts: Iterable[str],
metadatas: Optional[Iterable[dict[Any, Any]]] = None,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-4
|
metadatas: Optional[Iterable[dict[Any, Any]]] = None,
) -> List[Document]:
"""Return list of Documents from list of texts and metadatas."""
if metadatas is None:
metadatas = repeat({})
docs = [
Document(page_content=text, metadata=metadata)
for text, metadata in zip(texts, metadatas)
]
return docs
@staticmethod
def _add_vectors(
client: supabase.client.Client,
table_name: str,
vectors: List[List[float]],
documents: List[Document],
) -> List[str]:
"""Add vectors to Supabase table."""
rows: List[dict[str, Any]] = [
{
"content": documents[idx].page_content,
"embedding": embedding,
"metadata": documents[idx].metadata, # type: ignore
}
for idx, embedding in enumerate(vectors)
]
# According to the SupabaseVectorStore JS implementation, the best chunk size
# is 500
chunk_size = 500
id_list: List[str] = []
for i in range(0, len(rows), chunk_size):
chunk = rows[i : i + chunk_size]
result = client.from_(table_name).insert(chunk).execute() # type: ignore
if len(result.data) == 0:
raise Exception("Error inserting: No rows added")
# VectorStore.add_vectors returns ids as strings
ids = [str(i.get("id")) for i in result.data if i.get("id")]
id_list.extend(ids)
return id_list
[docs] def max_marginal_relevance_search_by_vector(
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-5
|
return id_list
[docs] def max_marginal_relevance_search_by_vector(
self,
embedding: List[float],
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
result = self.similarity_search_by_vector_returning_embeddings(
embedding, fetch_k
)
matched_documents = [doc_tuple[0] for doc_tuple in result]
matched_embeddings = [doc_tuple[2] for doc_tuple in result]
mmr_selected = maximal_marginal_relevance(
np.array([embedding], dtype=np.float32),
matched_embeddings,
k=k,
lambda_mult=lambda_mult,
)
filtered_documents = [matched_documents[i] for i in mmr_selected]
return filtered_documents
[docs] def max_marginal_relevance_search(
self,
query: str,
k: int = 4,
fetch_k: int = 20,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-6
|
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
`max_marginal_relevance_search` requires that `query_name` returns matched
embeddings alongside the match documents. The following function function
demonstrates how to do this:
```sql
CREATE FUNCTION match_documents_embeddings(query_embedding vector(1536),
match_count int)
RETURNS TABLE(
id bigint,
content text,
metadata jsonb,
embedding vector(1536),
similarity float)
LANGUAGE plpgsql
AS $$
# variable_conflict use_column
BEGIN
RETURN query
SELECT
id,
content,
metadata,
embedding,
1 -(docstore.embedding <=> query_embedding) AS similarity
FROM
docstore
ORDER BY
docstore.embedding <=> query_embedding
LIMIT match_count;
END;
$$;```
"""
embedding = self._embedding.embed_documents([query])
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
95f2afed514f-7
|
$$;```
"""
embedding = self._embedding.embed_documents([query])
docs = self.max_marginal_relevance_search_by_vector(
embedding[0], k, fetch_k, lambda_mult=lambda_mult
)
return docs
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/supabase.html
|
a2713e9c0aa0-0
|
Source code for langchain.vectorstores.chroma
"""Wrapper around ChromaDB embeddings platform."""
from __future__ import annotations
import logging
import uuid
from typing import TYPE_CHECKING, Any, Dict, Iterable, List, Optional, Tuple, Type
import numpy as np
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.utils import xor_args
from langchain.vectorstores.base import VectorStore
from langchain.vectorstores.utils import maximal_marginal_relevance
if TYPE_CHECKING:
import chromadb
import chromadb.config
logger = logging.getLogger(__name__)
def _results_to_docs(results: Any) -> List[Document]:
return [doc for doc, _ in _results_to_docs_and_scores(results)]
def _results_to_docs_and_scores(results: Any) -> List[Tuple[Document, float]]:
return [
# TODO: Chroma can do batch querying,
# we shouldn't hard code to the 1st result
(Document(page_content=result[0], metadata=result[1] or {}), result[2])
for result in zip(
results["documents"][0],
results["metadatas"][0],
results["distances"][0],
)
]
[docs]class Chroma(VectorStore):
"""Wrapper around ChromaDB embeddings platform.
To use, you should have the ``chromadb`` python package installed.
Example:
.. code-block:: python
from langchain.vectorstores import Chroma
from langchain.embeddings.openai import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
vectorstore = Chroma("langchain_store", embeddings.embed_query)
"""
_LANGCHAIN_DEFAULT_COLLECTION_NAME = "langchain"
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-1
|
"""
_LANGCHAIN_DEFAULT_COLLECTION_NAME = "langchain"
def __init__(
self,
collection_name: str = _LANGCHAIN_DEFAULT_COLLECTION_NAME,
embedding_function: Optional[Embeddings] = None,
persist_directory: Optional[str] = None,
client_settings: Optional[chromadb.config.Settings] = None,
collection_metadata: Optional[Dict] = None,
client: Optional[chromadb.Client] = None,
) -> None:
"""Initialize with Chroma client."""
try:
import chromadb
import chromadb.config
except ImportError:
raise ValueError(
"Could not import chromadb python package. "
"Please install it with `pip install chromadb`."
)
if client is not None:
self._client = client
else:
if client_settings:
self._client_settings = client_settings
else:
self._client_settings = chromadb.config.Settings()
if persist_directory is not None:
self._client_settings = chromadb.config.Settings(
chroma_db_impl="duckdb+parquet",
persist_directory=persist_directory,
)
self._client = chromadb.Client(self._client_settings)
self._embedding_function = embedding_function
self._persist_directory = persist_directory
self._collection = self._client.get_or_create_collection(
name=collection_name,
embedding_function=self._embedding_function.embed_documents
if self._embedding_function is not None
else None,
metadata=collection_metadata,
)
@xor_args(("query_texts", "query_embeddings"))
def __query_collection(
self,
query_texts: Optional[List[str]] = None,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-2
|
self,
query_texts: Optional[List[str]] = None,
query_embeddings: Optional[List[List[float]]] = None,
n_results: int = 4,
where: Optional[Dict[str, str]] = None,
) -> List[Document]:
"""Query the chroma collection."""
for i in range(n_results, 0, -1):
try:
return self._collection.query(
query_texts=query_texts,
query_embeddings=query_embeddings,
n_results=n_results,
where=where,
)
except chromadb.errors.NotEnoughElementsException:
logger.error(
f"Chroma collection {self._collection.name} "
f"contains fewer than {i} elements."
)
raise chromadb.errors.NotEnoughElementsException(
f"No documents found for Chroma collection {self._collection.name}"
)
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
**kwargs: Any,
) -> List[str]:
"""Run more texts through the embeddings and add to the vectorstore.
Args:
texts (Iterable[str]): Texts to add to the vectorstore.
metadatas (Optional[List[dict]], optional): Optional list of metadatas.
ids (Optional[List[str]], optional): Optional list of IDs.
Returns:
List[str]: List of IDs of the added texts.
"""
# TODO: Handle the case where the user doesn't provide ids on the Collection
if ids is None:
ids = [str(uuid.uuid1()) for _ in texts]
embeddings = None
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-3
|
ids = [str(uuid.uuid1()) for _ in texts]
embeddings = None
if self._embedding_function is not None:
embeddings = self._embedding_function.embed_documents(list(texts))
self._collection.add(
metadatas=metadatas, embeddings=embeddings, documents=texts, ids=ids
)
return ids
[docs] def similarity_search(
self,
query: str,
k: int = 4,
filter: Optional[Dict[str, str]] = None,
**kwargs: Any,
) -> List[Document]:
"""Run similarity search with Chroma.
Args:
query (str): Query text to search for.
k (int): Number of results to return. Defaults to 4.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List[Document]: List of documents most similar to the query text.
"""
docs_and_scores = self.similarity_search_with_score(query, k, filter=filter)
return [doc for doc, _ in docs_and_scores]
[docs] def similarity_search_by_vector(
self,
embedding: List[float],
k: int = 4,
filter: Optional[Dict[str, str]] = None,
**kwargs: Any,
) -> List[Document]:
"""Return docs most similar to embedding vector.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query vector.
"""
results = self.__query_collection(
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-4
|
"""
results = self.__query_collection(
query_embeddings=embedding, n_results=k, where=filter
)
return _results_to_docs(results)
[docs] def similarity_search_with_score(
self,
query: str,
k: int = 4,
filter: Optional[Dict[str, str]] = None,
**kwargs: Any,
) -> List[Tuple[Document, float]]:
"""Run similarity search with Chroma with distance.
Args:
query (str): Query text to search for.
k (int): Number of results to return. Defaults to 4.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List[Tuple[Document, float]]: List of documents most similar to the query
text with distance in float.
"""
if self._embedding_function is None:
results = self.__query_collection(
query_texts=[query], n_results=k, where=filter
)
else:
query_embedding = self._embedding_function.embed_query(query)
results = self.__query_collection(
query_embeddings=[query_embedding], n_results=k, where=filter
)
return _results_to_docs_and_scores(results)
[docs] def max_marginal_relevance_search_by_vector(
self,
embedding: List[float],
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
filter: Optional[Dict[str, str]] = None,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-5
|
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List of Documents selected by maximal marginal relevance.
"""
results = self.__query_collection(
query_embeddings=embedding,
n_results=fetch_k,
where=filter,
include=["metadatas", "documents", "distances", "embeddings"],
)
mmr_selected = maximal_marginal_relevance(
np.array(embedding, dtype=np.float32),
results["embeddings"][0],
k=k,
lambda_mult=lambda_mult,
)
candidates = _results_to_docs(results)
selected_results = [r for i, r in enumerate(candidates) if i in mmr_selected]
return selected_results
[docs] def max_marginal_relevance_search(
self,
query: str,
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
filter: Optional[Dict[str, str]] = None,
**kwargs: Any,
) -> List[Document]:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-6
|
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List of Documents selected by maximal marginal relevance.
"""
if self._embedding_function is None:
raise ValueError(
"For MMR search, you must specify an embedding function on" "creation."
)
embedding = self._embedding_function.embed_query(query)
docs = self.max_marginal_relevance_search_by_vector(
embedding, k, fetch_k, lambda_mul=lambda_mult, filter=filter
)
return docs
[docs] def delete_collection(self) -> None:
"""Delete the collection."""
self._client.delete_collection(self._collection.name)
[docs] def persist(self) -> None:
"""Persist the collection.
This can be used to explicitly persist the data to disk.
It will also be called automatically when the object is destroyed.
"""
if self._persist_directory is None:
raise ValueError(
"You must specify a persist_directory on"
"creation to persist the collection."
)
self._client.persist()
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-7
|
"creation to persist the collection."
)
self._client.persist()
[docs] def update_document(self, document_id: str, document: Document) -> None:
"""Update a document in the collection.
Args:
document_id (str): ID of the document to update.
document (Document): Document to update.
"""
text = document.page_content
metadata = document.metadata
self._collection.update_document(document_id, text, metadata)
[docs] @classmethod
def from_texts(
cls: Type[Chroma],
texts: List[str],
embedding: Optional[Embeddings] = None,
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
collection_name: str = _LANGCHAIN_DEFAULT_COLLECTION_NAME,
persist_directory: Optional[str] = None,
client_settings: Optional[chromadb.config.Settings] = None,
client: Optional[chromadb.Client] = None,
**kwargs: Any,
) -> Chroma:
"""Create a Chroma vectorstore from a raw documents.
If a persist_directory is specified, the collection will be persisted there.
Otherwise, the data will be ephemeral in-memory.
Args:
texts (List[str]): List of texts to add to the collection.
collection_name (str): Name of the collection to create.
persist_directory (Optional[str]): Directory to persist the collection.
embedding (Optional[Embeddings]): Embedding function. Defaults to None.
metadatas (Optional[List[dict]]): List of metadatas. Defaults to None.
ids (Optional[List[str]]): List of document IDs. Defaults to None.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-8
|
ids (Optional[List[str]]): List of document IDs. Defaults to None.
client_settings (Optional[chromadb.config.Settings]): Chroma client settings
Returns:
Chroma: Chroma vectorstore.
"""
chroma_collection = cls(
collection_name=collection_name,
embedding_function=embedding,
persist_directory=persist_directory,
client_settings=client_settings,
client=client,
)
chroma_collection.add_texts(texts=texts, metadatas=metadatas, ids=ids)
return chroma_collection
[docs] @classmethod
def from_documents(
cls: Type[Chroma],
documents: List[Document],
embedding: Optional[Embeddings] = None,
ids: Optional[List[str]] = None,
collection_name: str = _LANGCHAIN_DEFAULT_COLLECTION_NAME,
persist_directory: Optional[str] = None,
client_settings: Optional[chromadb.config.Settings] = None,
client: Optional[chromadb.Client] = None, # Add this line
**kwargs: Any,
) -> Chroma:
"""Create a Chroma vectorstore from a list of documents.
If a persist_directory is specified, the collection will be persisted there.
Otherwise, the data will be ephemeral in-memory.
Args:
collection_name (str): Name of the collection to create.
persist_directory (Optional[str]): Directory to persist the collection.
ids (Optional[List[str]]): List of document IDs. Defaults to None.
documents (List[Document]): List of documents to add to the vectorstore.
embedding (Optional[Embeddings]): Embedding function. Defaults to None.
client_settings (Optional[chromadb.config.Settings]): Chroma client settings
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
a2713e9c0aa0-9
|
client_settings (Optional[chromadb.config.Settings]): Chroma client settings
Returns:
Chroma: Chroma vectorstore.
"""
texts = [doc.page_content for doc in documents]
metadatas = [doc.metadata for doc in documents]
return cls.from_texts(
texts=texts,
embedding=embedding,
metadatas=metadatas,
ids=ids,
collection_name=collection_name,
persist_directory=persist_directory,
client_settings=client_settings,
client=client,
)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/chroma.html
|
2af6a0e52863-0
|
Source code for langchain.vectorstores.atlas
"""Wrapper around Atlas by Nomic."""
from __future__ import annotations
import logging
import uuid
from typing import Any, Iterable, List, Optional, Type
import numpy as np
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
logger = logging.getLogger(__name__)
[docs]class AtlasDB(VectorStore):
"""Wrapper around Atlas: Nomic's neural database and rhizomatic instrument.
To use, you should have the ``nomic`` python package installed.
Example:
.. code-block:: python
from langchain.vectorstores import AtlasDB
from langchain.embeddings.openai import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
vectorstore = AtlasDB("my_project", embeddings.embed_query)
"""
_ATLAS_DEFAULT_ID_FIELD = "atlas_id"
def __init__(
self,
name: str,
embedding_function: Optional[Embeddings] = None,
api_key: Optional[str] = None,
description: str = "A description for your project",
is_public: bool = True,
reset_project_if_exists: bool = False,
) -> None:
"""
Initialize the Atlas Client
Args:
name (str): The name of your project. If the project already exists,
it will be loaded.
embedding_function (Optional[Callable]): An optional function used for
embedding your data. If None, data will be embedded with
Nomic's embed model.
api_key (str): Your nomic API key
description (str): A description for your project.
is_public (bool): Whether your project is publicly accessible.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-1
|
is_public (bool): Whether your project is publicly accessible.
True by default.
reset_project_if_exists (bool): Whether to reset this project if it
already exists. Default False.
Generally userful during development and testing.
"""
try:
import nomic
from nomic import AtlasProject
except ImportError:
raise ValueError(
"Could not import nomic python package. "
"Please install it with `pip install nomic`."
)
if api_key is None:
raise ValueError("No API key provided. Sign up at atlas.nomic.ai!")
nomic.login(api_key)
self._embedding_function = embedding_function
modality = "text"
if self._embedding_function is not None:
modality = "embedding"
# Check if the project exists, create it if not
self.project = AtlasProject(
name=name,
description=description,
modality=modality,
is_public=is_public,
reset_project_if_exists=reset_project_if_exists,
unique_id_field=AtlasDB._ATLAS_DEFAULT_ID_FIELD,
)
self.project._latest_project_state()
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
refresh: bool = True,
**kwargs: Any,
) -> List[str]:
"""Run more texts through the embeddings and add to the vectorstore.
Args:
texts (Iterable[str]): Texts to add to the vectorstore.
metadatas (Optional[List[dict]], optional): Optional list of metadatas.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-2
|
metadatas (Optional[List[dict]], optional): Optional list of metadatas.
ids (Optional[List[str]]): An optional list of ids.
refresh(bool): Whether or not to refresh indices with the updated data.
Default True.
Returns:
List[str]: List of IDs of the added texts.
"""
if (
metadatas is not None
and len(metadatas) > 0
and "text" in metadatas[0].keys()
):
raise ValueError("Cannot accept key text in metadata!")
texts = list(texts)
if ids is None:
ids = [str(uuid.uuid1()) for _ in texts]
# Embedding upload case
if self._embedding_function is not None:
_embeddings = self._embedding_function.embed_documents(texts)
embeddings = np.stack(_embeddings)
if metadatas is None:
data = [
{AtlasDB._ATLAS_DEFAULT_ID_FIELD: ids[i], "text": texts[i]}
for i, _ in enumerate(texts)
]
else:
for i in range(len(metadatas)):
metadatas[i][AtlasDB._ATLAS_DEFAULT_ID_FIELD] = ids[i]
metadatas[i]["text"] = texts[i]
data = metadatas
self.project._validate_map_data_inputs(
[], id_field=AtlasDB._ATLAS_DEFAULT_ID_FIELD, data=data
)
with self.project.wait_for_project_lock():
self.project.add_embeddings(embeddings=embeddings, data=data)
# Text upload case
else:
if metadatas is None:
data = [
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-3
|
else:
if metadatas is None:
data = [
{"text": text, AtlasDB._ATLAS_DEFAULT_ID_FIELD: ids[i]}
for i, text in enumerate(texts)
]
else:
for i, text in enumerate(texts):
metadatas[i]["text"] = texts
metadatas[i][AtlasDB._ATLAS_DEFAULT_ID_FIELD] = ids[i]
data = metadatas
self.project._validate_map_data_inputs(
[], id_field=AtlasDB._ATLAS_DEFAULT_ID_FIELD, data=data
)
with self.project.wait_for_project_lock():
self.project.add_text(data)
if refresh:
if len(self.project.indices) > 0:
with self.project.wait_for_project_lock():
self.project.rebuild_maps()
return ids
[docs] def create_index(self, **kwargs: Any) -> Any:
"""Creates an index in your project.
See
https://docs.nomic.ai/atlas_api.html#nomic.project.AtlasProject.create_index
for full detail.
"""
with self.project.wait_for_project_lock():
return self.project.create_index(**kwargs)
[docs] def similarity_search(
self,
query: str,
k: int = 4,
**kwargs: Any,
) -> List[Document]:
"""Run similarity search with AtlasDB
Args:
query (str): Query text to search for.
k (int): Number of results to return. Defaults to 4.
Returns:
List[Document]: List of documents most similar to the query text.
"""
if self._embedding_function is None:
raise NotImplementedError(
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-4
|
"""
if self._embedding_function is None:
raise NotImplementedError(
"AtlasDB requires an embedding_function for text similarity search!"
)
_embedding = self._embedding_function.embed_documents([query])[0]
embedding = np.array(_embedding).reshape(1, -1)
with self.project.wait_for_project_lock():
neighbors, _ = self.project.projections[0].vector_search(
queries=embedding, k=k
)
datas = self.project.get_data(ids=neighbors[0])
docs = [
Document(page_content=datas[i]["text"], metadata=datas[i])
for i, neighbor in enumerate(neighbors)
]
return docs
[docs] @classmethod
def from_texts(
cls: Type[AtlasDB],
texts: List[str],
embedding: Optional[Embeddings] = None,
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
name: Optional[str] = None,
api_key: Optional[str] = None,
description: str = "A description for your project",
is_public: bool = True,
reset_project_if_exists: bool = False,
index_kwargs: Optional[dict] = None,
**kwargs: Any,
) -> AtlasDB:
"""Create an AtlasDB vectorstore from a raw documents.
Args:
texts (List[str]): The list of texts to ingest.
name (str): Name of the project to create.
api_key (str): Your nomic API key,
embedding (Optional[Embeddings]): Embedding function. Defaults to None.
metadatas (Optional[List[dict]]): List of metadatas. Defaults to None.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-5
|
ids (Optional[List[str]]): Optional list of document IDs. If None,
ids will be auto created
description (str): A description for your project.
is_public (bool): Whether your project is publicly accessible.
True by default.
reset_project_if_exists (bool): Whether to reset this project if it
already exists. Default False.
Generally userful during development and testing.
index_kwargs (Optional[dict]): Dict of kwargs for index creation.
See https://docs.nomic.ai/atlas_api.html
Returns:
AtlasDB: Nomic's neural database and finest rhizomatic instrument
"""
if name is None or api_key is None:
raise ValueError("`name` and `api_key` cannot be None.")
# Inject relevant kwargs
all_index_kwargs = {"name": name + "_index", "indexed_field": "text"}
if index_kwargs is not None:
for k, v in index_kwargs.items():
all_index_kwargs[k] = v
# Build project
atlasDB = cls(
name,
embedding_function=embedding,
api_key=api_key,
description="A description for your project",
is_public=is_public,
reset_project_if_exists=reset_project_if_exists,
)
with atlasDB.project.wait_for_project_lock():
atlasDB.add_texts(texts=texts, metadatas=metadatas, ids=ids)
atlasDB.create_index(**all_index_kwargs)
return atlasDB
[docs] @classmethod
def from_documents(
cls: Type[AtlasDB],
documents: List[Document],
embedding: Optional[Embeddings] = None,
ids: Optional[List[str]] = None,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-6
|
ids: Optional[List[str]] = None,
name: Optional[str] = None,
api_key: Optional[str] = None,
persist_directory: Optional[str] = None,
description: str = "A description for your project",
is_public: bool = True,
reset_project_if_exists: bool = False,
index_kwargs: Optional[dict] = None,
**kwargs: Any,
) -> AtlasDB:
"""Create an AtlasDB vectorstore from a list of documents.
Args:
name (str): Name of the collection to create.
api_key (str): Your nomic API key,
documents (List[Document]): List of documents to add to the vectorstore.
embedding (Optional[Embeddings]): Embedding function. Defaults to None.
ids (Optional[List[str]]): Optional list of document IDs. If None,
ids will be auto created
description (str): A description for your project.
is_public (bool): Whether your project is publicly accessible.
True by default.
reset_project_if_exists (bool): Whether to reset this project if
it already exists. Default False.
Generally userful during development and testing.
index_kwargs (Optional[dict]): Dict of kwargs for index creation.
See https://docs.nomic.ai/atlas_api.html
Returns:
AtlasDB: Nomic's neural database and finest rhizomatic instrument
"""
if name is None or api_key is None:
raise ValueError("`name` and `api_key` cannot be None.")
texts = [doc.page_content for doc in documents]
metadatas = [doc.metadata for doc in documents]
return cls.from_texts(
name=name,
api_key=api_key,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
2af6a0e52863-7
|
return cls.from_texts(
name=name,
api_key=api_key,
texts=texts,
embedding=embedding,
metadatas=metadatas,
ids=ids,
description=description,
is_public=is_public,
reset_project_if_exists=reset_project_if_exists,
index_kwargs=index_kwargs,
)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/atlas.html
|
d9df88db7060-0
|
Source code for langchain.vectorstores.opensearch_vector_search
"""Wrapper around OpenSearch vector database."""
from __future__ import annotations
import uuid
from typing import Any, Dict, Iterable, List, Optional
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.utils import get_from_dict_or_env
from langchain.vectorstores.base import VectorStore
IMPORT_OPENSEARCH_PY_ERROR = (
"Could not import OpenSearch. Please install it with `pip install opensearch-py`."
)
SCRIPT_SCORING_SEARCH = "script_scoring"
PAINLESS_SCRIPTING_SEARCH = "painless_scripting"
MATCH_ALL_QUERY = {"match_all": {}} # type: Dict
def _import_opensearch() -> Any:
"""Import OpenSearch if available, otherwise raise error."""
try:
from opensearchpy import OpenSearch
except ImportError:
raise ValueError(IMPORT_OPENSEARCH_PY_ERROR)
return OpenSearch
def _import_bulk() -> Any:
"""Import bulk if available, otherwise raise error."""
try:
from opensearchpy.helpers import bulk
except ImportError:
raise ValueError(IMPORT_OPENSEARCH_PY_ERROR)
return bulk
def _get_opensearch_client(opensearch_url: str, **kwargs: Any) -> Any:
"""Get OpenSearch client from the opensearch_url, otherwise raise error."""
try:
opensearch = _import_opensearch()
client = opensearch(opensearch_url, **kwargs)
except ValueError as e:
raise ValueError(
f"OpenSearch client string provided is not in proper format. "
f"Got error: {e} "
)
return client
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-1
|
f"Got error: {e} "
)
return client
def _validate_embeddings_and_bulk_size(embeddings_length: int, bulk_size: int) -> None:
"""Validate Embeddings Length and Bulk Size."""
if embeddings_length == 0:
raise RuntimeError("Embeddings size is zero")
if bulk_size < embeddings_length:
raise RuntimeError(
f"The embeddings count, {embeddings_length} is more than the "
f"[bulk_size], {bulk_size}. Increase the value of [bulk_size]."
)
def _bulk_ingest_embeddings(
client: Any,
index_name: str,
embeddings: List[List[float]],
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
vector_field: str = "vector_field",
text_field: str = "text",
) -> List[str]:
"""Bulk Ingest Embeddings into given index."""
bulk = _import_bulk()
requests = []
ids = []
for i, text in enumerate(texts):
metadata = metadatas[i] if metadatas else {}
_id = str(uuid.uuid4())
request = {
"_op_type": "index",
"_index": index_name,
vector_field: embeddings[i],
text_field: text,
"metadata": metadata,
"_id": _id,
}
requests.append(request)
ids.append(_id)
bulk(client, requests)
client.indices.refresh(index=index_name)
return ids
def _default_scripting_text_mapping(
dim: int,
vector_field: str = "vector_field",
) -> Dict:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-2
|
vector_field: str = "vector_field",
) -> Dict:
"""For Painless Scripting or Script Scoring,the default mapping to create index."""
return {
"mappings": {
"properties": {
vector_field: {"type": "knn_vector", "dimension": dim},
}
}
}
def _default_text_mapping(
dim: int,
engine: str = "nmslib",
space_type: str = "l2",
ef_search: int = 512,
ef_construction: int = 512,
m: int = 16,
vector_field: str = "vector_field",
) -> Dict:
"""For Approximate k-NN Search, this is the default mapping to create index."""
return {
"settings": {"index": {"knn": True, "knn.algo_param.ef_search": ef_search}},
"mappings": {
"properties": {
vector_field: {
"type": "knn_vector",
"dimension": dim,
"method": {
"name": "hnsw",
"space_type": space_type,
"engine": engine,
"parameters": {"ef_construction": ef_construction, "m": m},
},
}
}
},
}
def _default_approximate_search_query(
query_vector: List[float],
size: int = 4,
k: int = 4,
vector_field: str = "vector_field",
) -> Dict:
"""For Approximate k-NN Search, this is the default query."""
return {
"size": size,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-3
|
return {
"size": size,
"query": {"knn": {vector_field: {"vector": query_vector, "k": k}}},
}
def _approximate_search_query_with_boolean_filter(
query_vector: List[float],
boolean_filter: Dict,
size: int = 4,
k: int = 4,
vector_field: str = "vector_field",
subquery_clause: str = "must",
) -> Dict:
"""For Approximate k-NN Search, with Boolean Filter."""
return {
"size": size,
"query": {
"bool": {
"filter": boolean_filter,
subquery_clause: [
{"knn": {vector_field: {"vector": query_vector, "k": k}}}
],
}
},
}
def _approximate_search_query_with_lucene_filter(
query_vector: List[float],
lucene_filter: Dict,
size: int = 4,
k: int = 4,
vector_field: str = "vector_field",
) -> Dict:
"""For Approximate k-NN Search, with Lucene Filter."""
search_query = _default_approximate_search_query(
query_vector, size, k, vector_field
)
search_query["query"]["knn"][vector_field]["filter"] = lucene_filter
return search_query
def _default_script_query(
query_vector: List[float],
space_type: str = "l2",
pre_filter: Dict = MATCH_ALL_QUERY,
vector_field: str = "vector_field",
) -> Dict:
"""For Script Scoring Search, this is the default query."""
return {
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-4
|
"""For Script Scoring Search, this is the default query."""
return {
"query": {
"script_score": {
"query": pre_filter,
"script": {
"source": "knn_score",
"lang": "knn",
"params": {
"field": vector_field,
"query_value": query_vector,
"space_type": space_type,
},
},
}
}
}
def __get_painless_scripting_source(
space_type: str, query_vector: List[float], vector_field: str = "vector_field"
) -> str:
"""For Painless Scripting, it returns the script source based on space type."""
source_value = (
"(1.0 + "
+ space_type
+ "("
+ str(query_vector)
+ ", doc['"
+ vector_field
+ "']))"
)
if space_type == "cosineSimilarity":
return source_value
else:
return "1/" + source_value
def _default_painless_scripting_query(
query_vector: List[float],
space_type: str = "l2Squared",
pre_filter: Dict = MATCH_ALL_QUERY,
vector_field: str = "vector_field",
) -> Dict:
"""For Painless Scripting Search, this is the default query."""
source = __get_painless_scripting_source(space_type, query_vector)
return {
"query": {
"script_score": {
"query": pre_filter,
"script": {
"source": source,
"params": {
"field": vector_field,
"query_value": query_vector,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-5
|
"field": vector_field,
"query_value": query_vector,
},
},
}
}
}
def _get_kwargs_value(kwargs: Any, key: str, default_value: Any) -> Any:
"""Get the value of the key if present. Else get the default_value."""
if key in kwargs:
return kwargs.get(key)
return default_value
[docs]class OpenSearchVectorSearch(VectorStore):
"""Wrapper around OpenSearch as a vector database.
Example:
.. code-block:: python
from langchain import OpenSearchVectorSearch
opensearch_vector_search = OpenSearchVectorSearch(
"http://localhost:9200",
"embeddings",
embedding_function
)
"""
def __init__(
self,
opensearch_url: str,
index_name: str,
embedding_function: Embeddings,
**kwargs: Any,
):
"""Initialize with necessary components."""
self.embedding_function = embedding_function
self.index_name = index_name
self.client = _get_opensearch_client(opensearch_url, **kwargs)
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
bulk_size: int = 500,
**kwargs: Any,
) -> List[str]:
"""Run more texts through the embeddings and add to the vectorstore.
Args:
texts: Iterable of strings to add to the vectorstore.
metadatas: Optional list of metadatas associated with the texts.
bulk_size: Bulk API request count; Default: 500
Returns:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-6
|
bulk_size: Bulk API request count; Default: 500
Returns:
List of ids from adding the texts into the vectorstore.
Optional Args:
vector_field: Document field embeddings are stored in. Defaults to
"vector_field".
text_field: Document field the text of the document is stored in. Defaults
to "text".
"""
embeddings = self.embedding_function.embed_documents(list(texts))
_validate_embeddings_and_bulk_size(len(embeddings), bulk_size)
vector_field = _get_kwargs_value(kwargs, "vector_field", "vector_field")
text_field = _get_kwargs_value(kwargs, "text_field", "text")
return _bulk_ingest_embeddings(
self.client,
self.index_name,
embeddings,
texts,
metadatas,
vector_field,
text_field,
)
[docs] def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query.
By default supports Approximate Search.
Also supports Script Scoring and Painless Scripting.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query.
Optional Args:
vector_field: Document field embeddings are stored in. Defaults to
"vector_field".
text_field: Document field the text of the document is stored in. Defaults
to "text".
metadata_field: Document field that metadata is stored in. Defaults to
"metadata".
Can be set to a special value "*" to include the entire document.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-7
|
"metadata".
Can be set to a special value "*" to include the entire document.
Optional Args for Approximate Search:
search_type: "approximate_search"; default: "approximate_search"
size: number of results the query actually returns; default: 4
boolean_filter: A Boolean filter consists of a Boolean query that
contains a k-NN query and a filter.
subquery_clause: Query clause on the knn vector field; default: "must"
lucene_filter: the Lucene algorithm decides whether to perform an exact
k-NN search with pre-filtering or an approximate search with modified
post-filtering.
Optional Args for Script Scoring Search:
search_type: "script_scoring"; default: "approximate_search"
space_type: "l2", "l1", "linf", "cosinesimil", "innerproduct",
"hammingbit"; default: "l2"
pre_filter: script_score query to pre-filter documents before identifying
nearest neighbors; default: {"match_all": {}}
Optional Args for Painless Scripting Search:
search_type: "painless_scripting"; default: "approximate_search"
space_type: "l2Squared", "l1Norm", "cosineSimilarity"; default: "l2Squared"
pre_filter: script_score query to pre-filter documents before identifying
nearest neighbors; default: {"match_all": {}}
"""
embedding = self.embedding_function.embed_query(query)
search_type = _get_kwargs_value(kwargs, "search_type", "approximate_search")
text_field = _get_kwargs_value(kwargs, "text_field", "text")
metadata_field = _get_kwargs_value(kwargs, "metadata_field", "metadata")
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-8
|
metadata_field = _get_kwargs_value(kwargs, "metadata_field", "metadata")
vector_field = _get_kwargs_value(kwargs, "vector_field", "vector_field")
if search_type == "approximate_search":
size = _get_kwargs_value(kwargs, "size", 4)
boolean_filter = _get_kwargs_value(kwargs, "boolean_filter", {})
subquery_clause = _get_kwargs_value(kwargs, "subquery_clause", "must")
lucene_filter = _get_kwargs_value(kwargs, "lucene_filter", {})
if boolean_filter != {} and lucene_filter != {}:
raise ValueError(
"Both `boolean_filter` and `lucene_filter` are provided which "
"is invalid"
)
if boolean_filter != {}:
search_query = _approximate_search_query_with_boolean_filter(
embedding, boolean_filter, size, k, vector_field, subquery_clause
)
elif lucene_filter != {}:
search_query = _approximate_search_query_with_lucene_filter(
embedding, lucene_filter, size, k, vector_field
)
else:
search_query = _default_approximate_search_query(
embedding, size, k, vector_field
)
elif search_type == SCRIPT_SCORING_SEARCH:
space_type = _get_kwargs_value(kwargs, "space_type", "l2")
pre_filter = _get_kwargs_value(kwargs, "pre_filter", MATCH_ALL_QUERY)
search_query = _default_script_query(
embedding, space_type, pre_filter, vector_field
)
elif search_type == PAINLESS_SCRIPTING_SEARCH:
space_type = _get_kwargs_value(kwargs, "space_type", "l2Squared")
pre_filter = _get_kwargs_value(kwargs, "pre_filter", MATCH_ALL_QUERY)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-9
|
pre_filter = _get_kwargs_value(kwargs, "pre_filter", MATCH_ALL_QUERY)
search_query = _default_painless_scripting_query(
embedding, space_type, pre_filter, vector_field
)
else:
raise ValueError("Invalid `search_type` provided as an argument")
response = self.client.search(index=self.index_name, body=search_query)
hits = [hit["_source"] for hit in response["hits"]["hits"][:k]]
documents = [
Document(
page_content=hit[text_field],
metadata=hit
if metadata_field == "*" or metadata_field not in hit
else hit[metadata_field],
)
for hit in hits
]
return documents
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
bulk_size: int = 500,
**kwargs: Any,
) -> OpenSearchVectorSearch:
"""Construct OpenSearchVectorSearch wrapper from raw documents.
Example:
.. code-block:: python
from langchain import OpenSearchVectorSearch
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
opensearch_vector_search = OpenSearchVectorSearch.from_texts(
texts,
embeddings,
opensearch_url="http://localhost:9200"
)
OpenSearch by default supports Approximate Search powered by nmslib, faiss
and lucene engines recommended for large datasets. Also supports brute force
search through Script Scoring and Painless Scripting.
Optional Args:
vector_field: Document field embeddings are stored in. Defaults to
"vector_field".
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-10
|
vector_field: Document field embeddings are stored in. Defaults to
"vector_field".
text_field: Document field the text of the document is stored in. Defaults
to "text".
Optional Keyword Args for Approximate Search:
engine: "nmslib", "faiss", "lucene"; default: "nmslib"
space_type: "l2", "l1", "cosinesimil", "linf", "innerproduct"; default: "l2"
ef_search: Size of the dynamic list used during k-NN searches. Higher values
lead to more accurate but slower searches; default: 512
ef_construction: Size of the dynamic list used during k-NN graph creation.
Higher values lead to more accurate graph but slower indexing speed;
default: 512
m: Number of bidirectional links created for each new element. Large impact
on memory consumption. Between 2 and 100; default: 16
Keyword Args for Script Scoring or Painless Scripting:
is_appx_search: False
"""
opensearch_url = get_from_dict_or_env(
kwargs, "opensearch_url", "OPENSEARCH_URL"
)
# List of arguments that needs to be removed from kwargs
# before passing kwargs to get opensearch client
keys_list = [
"opensearch_url",
"index_name",
"is_appx_search",
"vector_field",
"text_field",
"engine",
"space_type",
"ef_search",
"ef_construction",
"m",
]
embeddings = embedding.embed_documents(texts)
_validate_embeddings_and_bulk_size(len(embeddings), bulk_size)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-11
|
_validate_embeddings_and_bulk_size(len(embeddings), bulk_size)
dim = len(embeddings[0])
# Get the index name from either from kwargs or ENV Variable
# before falling back to random generation
index_name = get_from_dict_or_env(
kwargs, "index_name", "OPENSEARCH_INDEX_NAME", default=uuid.uuid4().hex
)
is_appx_search = _get_kwargs_value(kwargs, "is_appx_search", True)
vector_field = _get_kwargs_value(kwargs, "vector_field", "vector_field")
text_field = _get_kwargs_value(kwargs, "text_field", "text")
if is_appx_search:
engine = _get_kwargs_value(kwargs, "engine", "nmslib")
space_type = _get_kwargs_value(kwargs, "space_type", "l2")
ef_search = _get_kwargs_value(kwargs, "ef_search", 512)
ef_construction = _get_kwargs_value(kwargs, "ef_construction", 512)
m = _get_kwargs_value(kwargs, "m", 16)
mapping = _default_text_mapping(
dim, engine, space_type, ef_search, ef_construction, m, vector_field
)
else:
mapping = _default_scripting_text_mapping(dim)
[kwargs.pop(key, None) for key in keys_list]
client = _get_opensearch_client(opensearch_url, **kwargs)
client.indices.create(index=index_name, body=mapping)
_bulk_ingest_embeddings(
client, index_name, embeddings, texts, metadatas, vector_field, text_field
)
return cls(opensearch_url, index_name, embedding, **kwargs)
By Harrison Chase
© Copyright 2023, Harrison Chase.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
d9df88db7060-12
|
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/opensearch_vector_search.html
|
90d5a42111da-0
|
Source code for langchain.vectorstores.analyticdb
"""VectorStore wrapper around a Postgres/PGVector database."""
from __future__ import annotations
import logging
import uuid
from typing import Any, Dict, Iterable, List, Optional, Tuple
import sqlalchemy
from sqlalchemy import REAL, Index
from sqlalchemy.dialects.postgresql import ARRAY, JSON, UUID
from sqlalchemy.orm import Mapped, Session, declarative_base, relationship
from sqlalchemy.sql.expression import func
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.utils import get_from_dict_or_env
from langchain.vectorstores.base import VectorStore
Base = declarative_base() # type: Any
ADA_TOKEN_COUNT = 1536
_LANGCHAIN_DEFAULT_COLLECTION_NAME = "langchain"
class BaseModel(Base):
__abstract__ = True
uuid = sqlalchemy.Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
class CollectionStore(BaseModel):
__tablename__ = "langchain_pg_collection"
name = sqlalchemy.Column(sqlalchemy.String)
cmetadata = sqlalchemy.Column(JSON)
embeddings = relationship(
"EmbeddingStore",
back_populates="collection",
passive_deletes=True,
)
@classmethod
def get_by_name(cls, session: Session, name: str) -> Optional["CollectionStore"]:
return session.query(cls).filter(cls.name == name).first()
@classmethod
def get_or_create(
cls,
session: Session,
name: str,
cmetadata: Optional[dict] = None,
) -> Tuple["CollectionStore", bool]:
"""
Get or create a collection.
Returns [Collection, bool] where the bool is True if the collection was created.
"""
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-1
|
"""
created = False
collection = cls.get_by_name(session, name)
if collection:
return collection, created
collection = cls(name=name, cmetadata=cmetadata)
session.add(collection)
session.commit()
created = True
return collection, created
class EmbeddingStore(BaseModel):
__tablename__ = "langchain_pg_embedding"
collection_id: Mapped[UUID] = sqlalchemy.Column(
UUID(as_uuid=True),
sqlalchemy.ForeignKey(
f"{CollectionStore.__tablename__}.uuid",
ondelete="CASCADE",
),
)
collection = relationship(CollectionStore, back_populates="embeddings")
embedding = sqlalchemy.Column(ARRAY(REAL))
document = sqlalchemy.Column(sqlalchemy.String, nullable=True)
cmetadata = sqlalchemy.Column(JSON, nullable=True)
# custom_id : any user defined id
custom_id = sqlalchemy.Column(sqlalchemy.String, nullable=True)
# The following line creates an index named 'langchain_pg_embedding_vector_idx'
langchain_pg_embedding_vector_idx = Index(
"langchain_pg_embedding_vector_idx",
embedding,
postgresql_using="ann",
postgresql_with={
"distancemeasure": "L2",
"dim": 1536,
"pq_segments": 64,
"hnsw_m": 100,
"pq_centers": 2048,
},
)
class QueryResult:
EmbeddingStore: EmbeddingStore
distance: float
[docs]class AnalyticDB(VectorStore):
"""
VectorStore implementation using AnalyticDB.
AnalyticDB is a distributed full PostgresSQL syntax cloud-native database.
- `connection_string` is a postgres connection string.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-2
|
- `connection_string` is a postgres connection string.
- `embedding_function` any embedding function implementing
`langchain.embeddings.base.Embeddings` interface.
- `collection_name` is the name of the collection to use. (default: langchain)
- NOTE: This is not the name of the table, but the name of the collection.
The tables will be created when initializing the store (if not exists)
So, make sure the user has the right permissions to create tables.
- `pre_delete_collection` if True, will delete the collection if it exists.
(default: False)
- Useful for testing.
"""
def __init__(
self,
connection_string: str,
embedding_function: Embeddings,
collection_name: str = _LANGCHAIN_DEFAULT_COLLECTION_NAME,
collection_metadata: Optional[dict] = None,
pre_delete_collection: bool = False,
logger: Optional[logging.Logger] = None,
) -> None:
self.connection_string = connection_string
self.embedding_function = embedding_function
self.collection_name = collection_name
self.collection_metadata = collection_metadata
self.pre_delete_collection = pre_delete_collection
self.logger = logger or logging.getLogger(__name__)
self.__post_init__()
def __post_init__(
self,
) -> None:
"""
Initialize the store.
"""
self._conn = self.connect()
self.create_tables_if_not_exists()
self.create_collection()
[docs] def connect(self) -> sqlalchemy.engine.Connection:
engine = sqlalchemy.create_engine(self.connection_string)
conn = engine.connect()
return conn
[docs] def create_tables_if_not_exists(self) -> None:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-3
|
return conn
[docs] def create_tables_if_not_exists(self) -> None:
Base.metadata.create_all(self._conn)
[docs] def drop_tables(self) -> None:
Base.metadata.drop_all(self._conn)
[docs] def create_collection(self) -> None:
if self.pre_delete_collection:
self.delete_collection()
with Session(self._conn) as session:
CollectionStore.get_or_create(
session, self.collection_name, cmetadata=self.collection_metadata
)
[docs] def delete_collection(self) -> None:
self.logger.debug("Trying to delete collection")
with Session(self._conn) as session:
collection = self.get_collection(session)
if not collection:
self.logger.error("Collection not found")
return
session.delete(collection)
session.commit()
[docs] def get_collection(self, session: Session) -> Optional["CollectionStore"]:
return CollectionStore.get_by_name(session, self.collection_name)
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
**kwargs: Any,
) -> List[str]:
"""Run more texts through the embeddings and add to the vectorstore.
Args:
texts: Iterable of strings to add to the vectorstore.
metadatas: Optional list of metadatas associated with the texts.
kwargs: vectorstore specific parameters
Returns:
List of ids from adding the texts into the vectorstore.
"""
if ids is None:
ids = [str(uuid.uuid1()) for _ in texts]
embeddings = self.embedding_function.embed_documents(list(texts))
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-4
|
embeddings = self.embedding_function.embed_documents(list(texts))
if not metadatas:
metadatas = [{} for _ in texts]
with Session(self._conn) as session:
collection = self.get_collection(session)
if not collection:
raise ValueError("Collection not found")
for text, metadata, embedding, id in zip(texts, metadatas, embeddings, ids):
embedding_store = EmbeddingStore(
embedding=embedding,
document=text,
cmetadata=metadata,
custom_id=id,
)
collection.embeddings.append(embedding_store)
session.add(embedding_store)
session.commit()
return ids
[docs] def similarity_search(
self,
query: str,
k: int = 4,
filter: Optional[dict] = None,
**kwargs: Any,
) -> List[Document]:
"""Run similarity search with AnalyticDB with distance.
Args:
query (str): Query text to search for.
k (int): Number of results to return. Defaults to 4.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List of Documents most similar to the query.
"""
embedding = self.embedding_function.embed_query(text=query)
return self.similarity_search_by_vector(
embedding=embedding,
k=k,
filter=filter,
)
[docs] def similarity_search_with_score(
self,
query: str,
k: int = 4,
filter: Optional[dict] = None,
) -> List[Tuple[Document, float]]:
"""Return docs most similar to query.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-5
|
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List of Documents most similar to the query and score for each
"""
embedding = self.embedding_function.embed_query(query)
docs = self.similarity_search_with_score_by_vector(
embedding=embedding, k=k, filter=filter
)
return docs
[docs] def similarity_search_with_score_by_vector(
self,
embedding: List[float],
k: int = 4,
filter: Optional[dict] = None,
) -> List[Tuple[Document, float]]:
with Session(self._conn) as session:
collection = self.get_collection(session)
if not collection:
raise ValueError("Collection not found")
filter_by = EmbeddingStore.collection_id == collection.uuid
if filter is not None:
filter_clauses = []
for key, value in filter.items():
filter_by_metadata = EmbeddingStore.cmetadata[key].astext == str(value)
filter_clauses.append(filter_by_metadata)
filter_by = sqlalchemy.and_(filter_by, *filter_clauses)
results: List[QueryResult] = (
session.query(
EmbeddingStore,
func.l2_distance(EmbeddingStore.embedding, embedding).label("distance"),
)
.filter(filter_by)
.order_by(EmbeddingStore.embedding.op("<->")(embedding))
.join(
CollectionStore,
EmbeddingStore.collection_id == CollectionStore.uuid,
)
.limit(k)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-6
|
EmbeddingStore.collection_id == CollectionStore.uuid,
)
.limit(k)
.all()
)
docs = [
(
Document(
page_content=result.EmbeddingStore.document,
metadata=result.EmbeddingStore.cmetadata,
),
result.distance if self.embedding_function is not None else None,
)
for result in results
]
return docs
[docs] def similarity_search_by_vector(
self,
embedding: List[float],
k: int = 4,
filter: Optional[dict] = None,
**kwargs: Any,
) -> List[Document]:
"""Return docs most similar to embedding vector.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
filter (Optional[Dict[str, str]]): Filter by metadata. Defaults to None.
Returns:
List of Documents most similar to the query vector.
"""
docs_and_scores = self.similarity_search_with_score_by_vector(
embedding=embedding, k=k, filter=filter
)
return [doc for doc, _ in docs_and_scores]
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
collection_name: str = _LANGCHAIN_DEFAULT_COLLECTION_NAME,
ids: Optional[List[str]] = None,
pre_delete_collection: bool = False,
**kwargs: Any,
) -> AnalyticDB:
"""
Return VectorStore initialized from texts and embeddings.
Postgres connection string is required
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-7
|
Return VectorStore initialized from texts and embeddings.
Postgres connection string is required
Either pass it as a parameter
or set the PGVECTOR_CONNECTION_STRING environment variable.
"""
connection_string = cls.get_connection_string(kwargs)
store = cls(
connection_string=connection_string,
collection_name=collection_name,
embedding_function=embedding,
pre_delete_collection=pre_delete_collection,
)
store.add_texts(texts=texts, metadatas=metadatas, ids=ids, **kwargs)
return store
[docs] @classmethod
def get_connection_string(cls, kwargs: Dict[str, Any]) -> str:
connection_string: str = get_from_dict_or_env(
data=kwargs,
key="connection_string",
env_key="PGVECTOR_CONNECTION_STRING",
)
if not connection_string:
raise ValueError(
"Postgres connection string is required"
"Either pass it as a parameter"
"or set the PGVECTOR_CONNECTION_STRING environment variable."
)
return connection_string
[docs] @classmethod
def from_documents(
cls,
documents: List[Document],
embedding: Embeddings,
collection_name: str = _LANGCHAIN_DEFAULT_COLLECTION_NAME,
ids: Optional[List[str]] = None,
pre_delete_collection: bool = False,
**kwargs: Any,
) -> AnalyticDB:
"""
Return VectorStore initialized from documents and embeddings.
Postgres connection string is required
Either pass it as a parameter
or set the PGVECTOR_CONNECTION_STRING environment variable.
"""
texts = [d.page_content for d in documents]
metadatas = [d.metadata for d in documents]
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
90d5a42111da-8
|
metadatas = [d.metadata for d in documents]
connection_string = cls.get_connection_string(kwargs)
kwargs["connection_string"] = connection_string
return cls.from_texts(
texts=texts,
pre_delete_collection=pre_delete_collection,
embedding=embedding,
metadatas=metadatas,
ids=ids,
collection_name=collection_name,
**kwargs,
)
[docs] @classmethod
def connection_string_from_db_params(
cls,
driver: str,
host: str,
port: int,
database: str,
user: str,
password: str,
) -> str:
"""Return connection string from database parameters."""
return f"postgresql+{driver}://{user}:{password}@{host}:{port}/{database}"
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/analyticdb.html
|
2b9cea1aac04-0
|
Source code for langchain.vectorstores.faiss
"""Wrapper around FAISS vector database."""
from __future__ import annotations
import math
import pickle
import uuid
from pathlib import Path
from typing import Any, Callable, Dict, Iterable, List, Optional, Tuple
import numpy as np
from langchain.docstore.base import AddableMixin, Docstore
from langchain.docstore.document import Document
from langchain.docstore.in_memory import InMemoryDocstore
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
from langchain.vectorstores.utils import maximal_marginal_relevance
def dependable_faiss_import() -> Any:
"""Import faiss if available, otherwise raise error."""
try:
import faiss
except ImportError:
raise ValueError(
"Could not import faiss python package. "
"Please install it with `pip install faiss` "
"or `pip install faiss-cpu` (depending on Python version)."
)
return faiss
def _default_relevance_score_fn(score: float) -> float:
"""Return a similarity score on a scale [0, 1]."""
# The 'correct' relevance function
# may differ depending on a few things, including:
# - the distance / similarity metric used by the VectorStore
# - the scale of your embeddings (OpenAI's are unit normed. Many others are not!)
# - embedding dimensionality
# - etc.
# This function converts the euclidean norm of normalized embeddings
# (0 is most similar, sqrt(2) most dissimilar)
# to a similarity function (0 to 1)
return 1.0 - score / math.sqrt(2)
[docs]class FAISS(VectorStore):
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-1
|
[docs]class FAISS(VectorStore):
"""Wrapper around FAISS vector database.
To use, you should have the ``faiss`` python package installed.
Example:
.. code-block:: python
from langchain import FAISS
faiss = FAISS(embedding_function, index, docstore, index_to_docstore_id)
"""
def __init__(
self,
embedding_function: Callable,
index: Any,
docstore: Docstore,
index_to_docstore_id: Dict[int, str],
relevance_score_fn: Optional[
Callable[[float], float]
] = _default_relevance_score_fn,
):
"""Initialize with necessary components."""
self.embedding_function = embedding_function
self.index = index
self.docstore = docstore
self.index_to_docstore_id = index_to_docstore_id
self.relevance_score_fn = relevance_score_fn
def __add(
self,
texts: Iterable[str],
embeddings: Iterable[List[float]],
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> List[str]:
if not isinstance(self.docstore, AddableMixin):
raise ValueError(
"If trying to add texts, the underlying docstore should support "
f"adding items, which {self.docstore} does not"
)
documents = []
for i, text in enumerate(texts):
metadata = metadatas[i] if metadatas else {}
documents.append(Document(page_content=text, metadata=metadata))
# Add to the index, the index_to_id mapping, and the docstore.
starting_len = len(self.index_to_docstore_id)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-2
|
starting_len = len(self.index_to_docstore_id)
self.index.add(np.array(embeddings, dtype=np.float32))
# Get list of index, id, and docs.
full_info = [
(starting_len + i, str(uuid.uuid4()), doc)
for i, doc in enumerate(documents)
]
# Add information to docstore and index.
self.docstore.add({_id: doc for _, _id, doc in full_info})
index_to_id = {index: _id for index, _id, _ in full_info}
self.index_to_docstore_id.update(index_to_id)
return [_id for _, _id, _ in full_info]
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> List[str]:
"""Run more texts through the embeddings and add to the vectorstore.
Args:
texts: Iterable of strings to add to the vectorstore.
metadatas: Optional list of metadatas associated with the texts.
Returns:
List of ids from adding the texts into the vectorstore.
"""
if not isinstance(self.docstore, AddableMixin):
raise ValueError(
"If trying to add texts, the underlying docstore should support "
f"adding items, which {self.docstore} does not"
)
# Embed and create the documents.
embeddings = [self.embedding_function(text) for text in texts]
return self.__add(texts, embeddings, metadatas, **kwargs)
[docs] def add_embeddings(
self,
text_embeddings: Iterable[Tuple[str, List[float]]],
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-3
|
self,
text_embeddings: Iterable[Tuple[str, List[float]]],
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> List[str]:
"""Run more texts through the embeddings and add to the vectorstore.
Args:
text_embeddings: Iterable pairs of string and embedding to
add to the vectorstore.
metadatas: Optional list of metadatas associated with the texts.
Returns:
List of ids from adding the texts into the vectorstore.
"""
if not isinstance(self.docstore, AddableMixin):
raise ValueError(
"If trying to add texts, the underlying docstore should support "
f"adding items, which {self.docstore} does not"
)
# Embed and create the documents.
texts = [te[0] for te in text_embeddings]
embeddings = [te[1] for te in text_embeddings]
return self.__add(texts, embeddings, metadatas, **kwargs)
[docs] def similarity_search_with_score_by_vector(
self, embedding: List[float], k: int = 4
) -> List[Tuple[Document, float]]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query and score for each
"""
scores, indices = self.index.search(np.array([embedding], dtype=np.float32), k)
docs = []
for j, i in enumerate(indices[0]):
if i == -1:
# This happens when not enough docs are returned.
continue
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-4
|
# This happens when not enough docs are returned.
continue
_id = self.index_to_docstore_id[i]
doc = self.docstore.search(_id)
if not isinstance(doc, Document):
raise ValueError(f"Could not find document for id {_id}, got {doc}")
docs.append((doc, scores[0][j]))
return docs
[docs] def similarity_search_with_score(
self, query: str, k: int = 4
) -> List[Tuple[Document, float]]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query and score for each
"""
embedding = self.embedding_function(query)
docs = self.similarity_search_with_score_by_vector(embedding, k)
return docs
[docs] def similarity_search_by_vector(
self, embedding: List[float], k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to embedding vector.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the embedding.
"""
docs_and_scores = self.similarity_search_with_score_by_vector(embedding, k)
return [doc for doc, _ in docs_and_scores]
[docs] def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query.
Args:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-5
|
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query.
"""
docs_and_scores = self.similarity_search_with_score(query, k)
return [doc for doc, _ in docs_and_scores]
[docs] def max_marginal_relevance_search_by_vector(
self,
embedding: List[float],
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
_, indices = self.index.search(np.array([embedding], dtype=np.float32), fetch_k)
# -1 happens when not enough docs are returned.
embeddings = [self.index.reconstruct(int(i)) for i in indices[0] if i != -1]
mmr_selected = maximal_marginal_relevance(
np.array([embedding], dtype=np.float32),
embeddings,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-6
|
np.array([embedding], dtype=np.float32),
embeddings,
k=k,
lambda_mult=lambda_mult,
)
selected_indices = [indices[0][i] for i in mmr_selected]
docs = []
for i in selected_indices:
if i == -1:
# This happens when not enough docs are returned.
continue
_id = self.index_to_docstore_id[i]
doc = self.docstore.search(_id)
if not isinstance(doc, Document):
raise ValueError(f"Could not find document for id {_id}, got {doc}")
docs.append(doc)
return docs
[docs] def max_marginal_relevance_search(
self,
query: str,
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
embedding = self.embedding_function(query)
docs = self.max_marginal_relevance_search_by_vector(
embedding, k, fetch_k, lambda_mult=lambda_mult
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-7
|
embedding, k, fetch_k, lambda_mult=lambda_mult
)
return docs
[docs] def merge_from(self, target: FAISS) -> None:
"""Merge another FAISS object with the current one.
Add the target FAISS to the current one.
Args:
target: FAISS object you wish to merge into the current one
Returns:
None.
"""
if not isinstance(self.docstore, AddableMixin):
raise ValueError("Cannot merge with this type of docstore")
# Numerical index for target docs are incremental on existing ones
starting_len = len(self.index_to_docstore_id)
# Merge two IndexFlatL2
self.index.merge_from(target.index)
# Create new id for docs from target FAISS object
full_info = []
for i in target.index_to_docstore_id:
doc = target.docstore.search(target.index_to_docstore_id[i])
if not isinstance(doc, Document):
raise ValueError("Document should be returned")
full_info.append((starting_len + i, str(uuid.uuid4()), doc))
# Add information to docstore and index_to_docstore_id.
self.docstore.add({_id: doc for _, _id, doc in full_info})
index_to_id = {index: _id for index, _id, _ in full_info}
self.index_to_docstore_id.update(index_to_id)
@classmethod
def __from(
cls,
texts: List[str],
embeddings: List[List[float]],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> FAISS:
faiss = dependable_faiss_import()
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-8
|
) -> FAISS:
faiss = dependable_faiss_import()
index = faiss.IndexFlatL2(len(embeddings[0]))
index.add(np.array(embeddings, dtype=np.float32))
documents = []
for i, text in enumerate(texts):
metadata = metadatas[i] if metadatas else {}
documents.append(Document(page_content=text, metadata=metadata))
index_to_id = {i: str(uuid.uuid4()) for i in range(len(documents))}
docstore = InMemoryDocstore(
{index_to_id[i]: doc for i, doc in enumerate(documents)}
)
return cls(embedding.embed_query, index, docstore, index_to_id, **kwargs)
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> FAISS:
"""Construct FAISS wrapper from raw documents.
This is a user friendly interface that:
1. Embeds documents.
2. Creates an in memory docstore
3. Initializes the FAISS database
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import FAISS
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
faiss = FAISS.from_texts(texts, embeddings)
"""
embeddings = embedding.embed_documents(texts)
return cls.__from(
texts,
embeddings,
embedding,
metadatas,
**kwargs,
)
[docs] @classmethod
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-9
|
metadatas,
**kwargs,
)
[docs] @classmethod
def from_embeddings(
cls,
text_embeddings: List[Tuple[str, List[float]]],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> FAISS:
"""Construct FAISS wrapper from raw documents.
This is a user friendly interface that:
1. Embeds documents.
2. Creates an in memory docstore
3. Initializes the FAISS database
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import FAISS
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
text_embeddings = embeddings.embed_documents(texts)
text_embedding_pairs = list(zip(texts, text_embeddings))
faiss = FAISS.from_embeddings(text_embedding_pairs, embeddings)
"""
texts = [t[0] for t in text_embeddings]
embeddings = [t[1] for t in text_embeddings]
return cls.__from(
texts,
embeddings,
embedding,
metadatas,
**kwargs,
)
[docs] def save_local(self, folder_path: str, index_name: str = "index") -> None:
"""Save FAISS index, docstore, and index_to_docstore_id to disk.
Args:
folder_path: folder path to save index, docstore,
and index_to_docstore_id to.
index_name: for saving with a specific index file name
"""
path = Path(folder_path)
path.mkdir(exist_ok=True, parents=True)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-10
|
path = Path(folder_path)
path.mkdir(exist_ok=True, parents=True)
# save index separately since it is not picklable
faiss = dependable_faiss_import()
faiss.write_index(
self.index, str(path / "{index_name}.faiss".format(index_name=index_name))
)
# save docstore and index_to_docstore_id
with open(path / "{index_name}.pkl".format(index_name=index_name), "wb") as f:
pickle.dump((self.docstore, self.index_to_docstore_id), f)
[docs] @classmethod
def load_local(
cls, folder_path: str, embeddings: Embeddings, index_name: str = "index"
) -> FAISS:
"""Load FAISS index, docstore, and index_to_docstore_id to disk.
Args:
folder_path: folder path to load index, docstore,
and index_to_docstore_id from.
embeddings: Embeddings to use when generating queries
index_name: for saving with a specific index file name
"""
path = Path(folder_path)
# load index separately since it is not picklable
faiss = dependable_faiss_import()
index = faiss.read_index(
str(path / "{index_name}.faiss".format(index_name=index_name))
)
# load docstore and index_to_docstore_id
with open(path / "{index_name}.pkl".format(index_name=index_name), "rb") as f:
docstore, index_to_docstore_id = pickle.load(f)
return cls(embeddings.embed_query, index, docstore, index_to_docstore_id)
def _similarity_search_with_relevance_scores(
self,
query: str,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
2b9cea1aac04-11
|
self,
query: str,
k: int = 4,
**kwargs: Any,
) -> List[Tuple[Document, float]]:
"""Return docs and their similarity scores on a scale from 0 to 1."""
if self.relevance_score_fn is None:
raise ValueError(
"normalize_score_fn must be provided to"
" FAISS constructor to normalize scores"
)
docs_and_scores = self.similarity_search_with_score(query, k=k)
return [(doc, self.relevance_score_fn(score)) for doc, score in docs_and_scores]
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/faiss.html
|
46ec4d20b726-0
|
Source code for langchain.vectorstores.milvus
"""Wrapper around the Milvus vector database."""
from __future__ import annotations
import logging
from typing import Any, Iterable, List, Optional, Tuple, Union
from uuid import uuid4
import numpy as np
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
from langchain.vectorstores.utils import maximal_marginal_relevance
logger = logging.getLogger(__name__)
DEFAULT_MILVUS_CONNECTION = {
"host": "localhost",
"port": "19530",
"user": "",
"password": "",
"secure": False,
}
[docs]class Milvus(VectorStore):
"""Wrapper around the Milvus vector database."""
def __init__(
self,
embedding_function: Embeddings,
collection_name: str = "LangChainCollection",
connection_args: Optional[dict[str, Any]] = None,
consistency_level: str = "Session",
index_params: Optional[dict] = None,
search_params: Optional[dict] = None,
drop_old: Optional[bool] = False,
):
"""Initialize wrapper around the milvus vector database.
In order to use this you need to have `pymilvus` installed and a
running Milvus/Zilliz Cloud instance.
See the following documentation for how to run a Milvus instance:
https://milvus.io/docs/install_standalone-docker.md
If looking for a hosted Milvus, take a looka this documentation:
https://zilliz.com/cloud
IF USING L2/IP metric IT IS HIGHLY SUGGESTED TO NORMALIZE YOUR DATA.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-1
|
The connection args used for this class comes in the form of a dict,
here are a few of the options:
address (str): The actual address of Milvus
instance. Example address: "localhost:19530"
uri (str): The uri of Milvus instance. Example uri:
"http://randomwebsite:19530",
"tcp:foobarsite:19530",
"https://ok.s3.south.com:19530".
host (str): The host of Milvus instance. Default at "localhost",
PyMilvus will fill in the default host if only port is provided.
port (str/int): The port of Milvus instance. Default at 19530, PyMilvus
will fill in the default port if only host is provided.
user (str): Use which user to connect to Milvus instance. If user and
password are provided, we will add related header in every RPC call.
password (str): Required when user is provided. The password
corresponding to the user.
secure (bool): Default is false. If set to true, tls will be enabled.
client_key_path (str): If use tls two-way authentication, need to
write the client.key path.
client_pem_path (str): If use tls two-way authentication, need to
write the client.pem path.
ca_pem_path (str): If use tls two-way authentication, need to write
the ca.pem path.
server_pem_path (str): If use tls one-way authentication, need to
write the server.pem path.
server_name (str): If use tls, need to write the common name.
Args:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-2
|
Args:
embedding_function (Embeddings): Function used to embed the text.
collection_name (str): Which Milvus collection to use. Defaults to
"LangChainCollection".
connection_args (Optional[dict[str, any]]): The arguments for connection to
Milvus/Zilliz instance. Defaults to DEFAULT_MILVUS_CONNECTION.
consistency_level (str): The consistency level to use for a collection.
Defaults to "Session".
index_params (Optional[dict]): Which index params to use. Defaults to
HNSW/AUTOINDEX depending on service.
search_params (Optional[dict]): Which search params to use. Defaults to
default of index.
drop_old (Optional[bool]): Whether to drop the current collection. Defaults
to False.
"""
try:
from pymilvus import Collection, utility
except ImportError:
raise ValueError(
"Could not import pymilvus python package. "
"Please install it with `pip install pymilvus`."
)
# Default search params when one is not provided.
self.default_search_params = {
"IVF_FLAT": {"metric_type": "L2", "params": {"nprobe": 10}},
"IVF_SQ8": {"metric_type": "L2", "params": {"nprobe": 10}},
"IVF_PQ": {"metric_type": "L2", "params": {"nprobe": 10}},
"HNSW": {"metric_type": "L2", "params": {"ef": 10}},
"RHNSW_FLAT": {"metric_type": "L2", "params": {"ef": 10}},
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-3
|
"RHNSW_SQ": {"metric_type": "L2", "params": {"ef": 10}},
"RHNSW_PQ": {"metric_type": "L2", "params": {"ef": 10}},
"IVF_HNSW": {"metric_type": "L2", "params": {"nprobe": 10, "ef": 10}},
"ANNOY": {"metric_type": "L2", "params": {"search_k": 10}},
"AUTOINDEX": {"metric_type": "L2", "params": {}},
}
self.embedding_func = embedding_function
self.collection_name = collection_name
self.index_params = index_params
self.search_params = search_params
self.consistency_level = consistency_level
# In order for a collection to be compatible, pk needs to be auto'id and int
self._primary_field = "pk"
# In order for compatiblility, the text field will need to be called "text"
self._text_field = "text"
# In order for compatbility, the vector field needs to be called "vector"
self._vector_field = "vector"
self.fields: list[str] = []
# Create the connection to the server
if connection_args is None:
connection_args = DEFAULT_MILVUS_CONNECTION
self.alias = self._create_connection_alias(connection_args)
self.col: Optional[Collection] = None
# Grab the existing colection if it exists
if utility.has_collection(self.collection_name, using=self.alias):
self.col = Collection(
self.collection_name,
using=self.alias,
)
# If need to drop old, drop it
if drop_old and isinstance(self.col, Collection):
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-4
|
if drop_old and isinstance(self.col, Collection):
self.col.drop()
self.col = None
# Initialize the vector store
self._init()
def _create_connection_alias(self, connection_args: dict) -> str:
"""Create the connection to the Milvus server."""
from pymilvus import MilvusException, connections
# Grab the connection arguments that are used for checking existing connection
host: str = connection_args.get("host", None)
port: Union[str, int] = connection_args.get("port", None)
address: str = connection_args.get("address", None)
uri: str = connection_args.get("uri", None)
user = connection_args.get("user", None)
# Order of use is host/port, uri, address
if host is not None and port is not None:
given_address = str(host) + ":" + str(port)
elif uri is not None:
given_address = uri.split("https://")[1]
elif address is not None:
given_address = address
else:
given_address = None
logger.debug("Missing standard address type for reuse atttempt")
# User defaults to empty string when getting connection info
if user is not None:
tmp_user = user
else:
tmp_user = ""
# If a valid address was given, then check if a connection exists
if given_address is not None:
for con in connections.list_connections():
addr = connections.get_connection_addr(con[0])
if (
con[1]
and ("address" in addr)
and (addr["address"] == given_address)
and ("user" in addr)
and (addr["user"] == tmp_user)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-5
|
and ("user" in addr)
and (addr["user"] == tmp_user)
):
logger.debug("Using previous connection: %s", con[0])
return con[0]
# Generate a new connection if one doesnt exist
alias = uuid4().hex
try:
connections.connect(alias=alias, **connection_args)
logger.debug("Created new connection using: %s", alias)
return alias
except MilvusException as e:
logger.error("Failed to create new connection using: %s", alias)
raise e
def _init(
self, embeddings: Optional[list] = None, metadatas: Optional[list[dict]] = None
) -> None:
if embeddings is not None:
self._create_collection(embeddings, metadatas)
self._extract_fields()
self._create_index()
self._create_search_params()
self._load()
def _create_collection(
self, embeddings: list, metadatas: Optional[list[dict]] = None
) -> None:
from pymilvus import (
Collection,
CollectionSchema,
DataType,
FieldSchema,
MilvusException,
)
from pymilvus.orm.types import infer_dtype_bydata
# Determine embedding dim
dim = len(embeddings[0])
fields = []
# Determine metadata schema
if metadatas:
# Create FieldSchema for each entry in metadata.
for key, value in metadatas[0].items():
# Infer the corresponding datatype of the metadata
dtype = infer_dtype_bydata(value)
# Datatype isnt compatible
if dtype == DataType.UNKNOWN or dtype == DataType.NONE:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-6
|
# Datatype isnt compatible
if dtype == DataType.UNKNOWN or dtype == DataType.NONE:
logger.error(
"Failure to create collection, unrecognized dtype for key: %s",
key,
)
raise ValueError(f"Unrecognized datatype for {key}.")
# Dataype is a string/varchar equivalent
elif dtype == DataType.VARCHAR:
fields.append(FieldSchema(key, DataType.VARCHAR, max_length=65_535))
else:
fields.append(FieldSchema(key, dtype))
# Create the text field
fields.append(
FieldSchema(self._text_field, DataType.VARCHAR, max_length=65_535)
)
# Create the primary key field
fields.append(
FieldSchema(
self._primary_field, DataType.INT64, is_primary=True, auto_id=True
)
)
# Create the vector field, supports binary or float vectors
fields.append(
FieldSchema(self._vector_field, infer_dtype_bydata(embeddings[0]), dim=dim)
)
# Create the schema for the collection
schema = CollectionSchema(fields)
# Create the collection
try:
self.col = Collection(
name=self.collection_name,
schema=schema,
consistency_level=self.consistency_level,
using=self.alias,
)
except MilvusException as e:
logger.error(
"Failed to create collection: %s error: %s", self.collection_name, e
)
raise e
def _extract_fields(self) -> None:
"""Grab the existing fields from the Collection"""
from pymilvus import Collection
if isinstance(self.col, Collection):
schema = self.col.schema
for x in schema.fields:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-7
|
schema = self.col.schema
for x in schema.fields:
self.fields.append(x.name)
# Since primary field is auto-id, no need to track it
self.fields.remove(self._primary_field)
def _get_index(self) -> Optional[dict[str, Any]]:
"""Return the vector index information if it exists"""
from pymilvus import Collection
if isinstance(self.col, Collection):
for x in self.col.indexes:
if x.field_name == self._vector_field:
return x.to_dict()
return None
def _create_index(self) -> None:
"""Create a index on the collection"""
from pymilvus import Collection, MilvusException
if isinstance(self.col, Collection) and self._get_index() is None:
try:
# If no index params, use a default HNSW based one
if self.index_params is None:
self.index_params = {
"metric_type": "L2",
"index_type": "HNSW",
"params": {"M": 8, "efConstruction": 64},
}
try:
self.col.create_index(
self._vector_field,
index_params=self.index_params,
using=self.alias,
)
# If default did not work, most likely on Zilliz Cloud
except MilvusException:
# Use AUTOINDEX based index
self.index_params = {
"metric_type": "L2",
"index_type": "AUTOINDEX",
"params": {},
}
self.col.create_index(
self._vector_field,
index_params=self.index_params,
using=self.alias,
)
logger.debug(
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-8
|
using=self.alias,
)
logger.debug(
"Successfully created an index on collection: %s",
self.collection_name,
)
except MilvusException as e:
logger.error(
"Failed to create an index on collection: %s", self.collection_name
)
raise e
def _create_search_params(self) -> None:
"""Generate search params based on the current index type"""
from pymilvus import Collection
if isinstance(self.col, Collection) and self.search_params is None:
index = self._get_index()
if index is not None:
index_type: str = index["index_param"]["index_type"]
metric_type: str = index["index_param"]["metric_type"]
self.search_params = self.default_search_params[index_type]
self.search_params["metric_type"] = metric_type
def _load(self) -> None:
"""Load the collection if available."""
from pymilvus import Collection
if isinstance(self.col, Collection) and self._get_index() is not None:
self.col.load()
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
timeout: Optional[int] = None,
batch_size: int = 1000,
**kwargs: Any,
) -> List[str]:
"""Insert text data into Milvus.
Inserting data when the collection has not be made yet will result
in creating a new Collection. The data of the first entity decides
the schema of the new collection, the dim is extracted from the first
embedding and the columns are decided by the first metadata dict.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-9
|
embedding and the columns are decided by the first metadata dict.
Metada keys will need to be present for all inserted values. At
the moment there is no None equivalent in Milvus.
Args:
texts (Iterable[str]): The texts to embed, it is assumed
that they all fit in memory.
metadatas (Optional[List[dict]]): Metadata dicts attached to each of
the texts. Defaults to None.
timeout (Optional[int]): Timeout for each batch insert. Defaults
to None.
batch_size (int, optional): Batch size to use for insertion.
Defaults to 1000.
Raises:
MilvusException: Failure to add texts
Returns:
List[str]: The resulting keys for each inserted element.
"""
from pymilvus import Collection, MilvusException
texts = list(texts)
try:
embeddings = self.embedding_func.embed_documents(texts)
except NotImplementedError:
embeddings = [self.embedding_func.embed_query(x) for x in texts]
if len(embeddings) == 0:
logger.debug("Nothing to insert, skipping.")
return []
# If the collection hasnt been initialized yet, perform all steps to do so
if not isinstance(self.col, Collection):
self._init(embeddings, metadatas)
# Dict to hold all insert columns
insert_dict: dict[str, list] = {
self._text_field: texts,
self._vector_field: embeddings,
}
# Collect the metadata into the insert dict.
if metadatas is not None:
for d in metadatas:
for key, value in d.items():
if key in self.fields:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-10
|
for key, value in d.items():
if key in self.fields:
insert_dict.setdefault(key, []).append(value)
# Total insert count
vectors: list = insert_dict[self._vector_field]
total_count = len(vectors)
pks: list[str] = []
assert isinstance(self.col, Collection)
for i in range(0, total_count, batch_size):
# Grab end index
end = min(i + batch_size, total_count)
# Convert dict to list of lists batch for insertion
insert_list = [insert_dict[x][i:end] for x in self.fields]
# Insert into the collection.
try:
res: Collection
res = self.col.insert(insert_list, timeout=timeout, **kwargs)
pks.extend(res.primary_keys)
except MilvusException as e:
logger.error(
"Failed to insert batch starting at entity: %s/%s", i, total_count
)
raise e
return pks
[docs] def similarity_search(
self,
query: str,
k: int = 4,
param: Optional[dict] = None,
expr: Optional[str] = None,
timeout: Optional[int] = None,
**kwargs: Any,
) -> List[Document]:
"""Perform a similarity search against the query string.
Args:
query (str): The text to search.
k (int, optional): How many results to return. Defaults to 4.
param (dict, optional): The search params for the index type.
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-11
|
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
timeout (int, optional): How long to wait before timeout error.
Defaults to None.
kwargs: Collection.search() keyword arguments.
Returns:
List[Document]: Document results for search.
"""
if self.col is None:
logger.debug("No existing collection to search.")
return []
res = self.similarity_search_with_score(
query=query, k=k, param=param, expr=expr, timeout=timeout, **kwargs
)
return [doc for doc, _ in res]
[docs] def similarity_search_by_vector(
self,
embedding: List[float],
k: int = 4,
param: Optional[dict] = None,
expr: Optional[str] = None,
timeout: Optional[int] = None,
**kwargs: Any,
) -> List[Document]:
"""Perform a similarity search against the query string.
Args:
embedding (List[float]): The embedding vector to search.
k (int, optional): How many results to return. Defaults to 4.
param (dict, optional): The search params for the index type.
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
timeout (int, optional): How long to wait before timeout error.
Defaults to None.
kwargs: Collection.search() keyword arguments.
Returns:
List[Document]: Document results for search.
"""
if self.col is None:
logger.debug("No existing collection to search.")
return []
res = self.similarity_search_with_score_by_vector(
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-12
|
return []
res = self.similarity_search_with_score_by_vector(
embedding=embedding, k=k, param=param, expr=expr, timeout=timeout, **kwargs
)
return [doc for doc, _ in res]
[docs] def similarity_search_with_score(
self,
query: str,
k: int = 4,
param: Optional[dict] = None,
expr: Optional[str] = None,
timeout: Optional[int] = None,
**kwargs: Any,
) -> List[Tuple[Document, float]]:
"""Perform a search on a query string and return results with score.
For more information about the search parameters, take a look at the pymilvus
documentation found here:
https://milvus.io/api-reference/pymilvus/v2.2.6/Collection/search().md
Args:
query (str): The text being searched.
k (int, optional): The amount of results ot return. Defaults to 4.
param (dict): The search params for the specified index.
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
timeout (int, optional): How long to wait before timeout error.
Defaults to None.
kwargs: Collection.search() keyword arguments.
Returns:
List[float], List[Tuple[Document, any, any]]:
"""
if self.col is None:
logger.debug("No existing collection to search.")
return []
# Embed the query text.
embedding = self.embedding_func.embed_query(query)
# Determine result metadata fields.
output_fields = self.fields[:]
output_fields.remove(self._vector_field)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-13
|
output_fields = self.fields[:]
output_fields.remove(self._vector_field)
res = self.similarity_search_with_score_by_vector(
embedding=embedding, k=k, param=param, expr=expr, timeout=timeout, **kwargs
)
return res
[docs] def similarity_search_with_score_by_vector(
self,
embedding: List[float],
k: int = 4,
param: Optional[dict] = None,
expr: Optional[str] = None,
timeout: Optional[int] = None,
**kwargs: Any,
) -> List[Tuple[Document, float]]:
"""Perform a search on a query string and return results with score.
For more information about the search parameters, take a look at the pymilvus
documentation found here:
https://milvus.io/api-reference/pymilvus/v2.2.6/Collection/search().md
Args:
embedding (List[float]): The embedding vector being searched.
k (int, optional): The amount of results ot return. Defaults to 4.
param (dict): The search params for the specified index.
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
timeout (int, optional): How long to wait before timeout error.
Defaults to None.
kwargs: Collection.search() keyword arguments.
Returns:
List[Tuple[Document, float]]: Result doc and score.
"""
if self.col is None:
logger.debug("No existing collection to search.")
return []
if param is None:
param = self.search_params
# Determine result metadata fields.
output_fields = self.fields[:]
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-14
|
# Determine result metadata fields.
output_fields = self.fields[:]
output_fields.remove(self._vector_field)
# Perform the search.
res = self.col.search(
data=[embedding],
anns_field=self._vector_field,
param=param,
limit=k,
expr=expr,
output_fields=output_fields,
timeout=timeout,
**kwargs,
)
# Organize results.
ret = []
for result in res[0]:
meta = {x: result.entity.get(x) for x in output_fields}
doc = Document(page_content=meta.pop(self._text_field), metadata=meta)
pair = (doc, result.score)
ret.append(pair)
return ret
[docs] def max_marginal_relevance_search(
self,
query: str,
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
param: Optional[dict] = None,
expr: Optional[str] = None,
timeout: Optional[int] = None,
**kwargs: Any,
) -> List[Document]:
"""Perform a search and return results that are reordered by MMR.
Args:
query (str): The text being searched.
k (int, optional): How many results to give. Defaults to 4.
fetch_k (int, optional): Total results to select k from.
Defaults to 20.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-15
|
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5
param (dict, optional): The search params for the specified index.
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
timeout (int, optional): How long to wait before timeout error.
Defaults to None.
kwargs: Collection.search() keyword arguments.
Returns:
List[Document]: Document results for search.
"""
if self.col is None:
logger.debug("No existing collection to search.")
return []
embedding = self.embedding_func.embed_query(query)
return self.max_marginal_relevance_search_by_vector(
embedding=embedding,
k=k,
fetch_k=fetch_k,
lambda_mult=lambda_mult,
param=param,
expr=expr,
timeout=timeout,
**kwargs,
)
[docs] def max_marginal_relevance_search_by_vector(
self,
embedding: list[float],
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
param: Optional[dict] = None,
expr: Optional[str] = None,
timeout: Optional[int] = None,
**kwargs: Any,
) -> List[Document]:
"""Perform a search and return results that are reordered by MMR.
Args:
embedding (str): The embedding vector being searched.
k (int, optional): How many results to give. Defaults to 4.
fetch_k (int, optional): Total results to select k from.
Defaults to 20.
lambda_mult: Number between 0 and 1 that determines the degree
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-16
|
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5
param (dict, optional): The search params for the specified index.
Defaults to None.
expr (str, optional): Filtering expression. Defaults to None.
timeout (int, optional): How long to wait before timeout error.
Defaults to None.
kwargs: Collection.search() keyword arguments.
Returns:
List[Document]: Document results for search.
"""
if self.col is None:
logger.debug("No existing collection to search.")
return []
if param is None:
param = self.search_params
# Determine result metadata fields.
output_fields = self.fields[:]
output_fields.remove(self._vector_field)
# Perform the search.
res = self.col.search(
data=[embedding],
anns_field=self._vector_field,
param=param,
limit=fetch_k,
expr=expr,
output_fields=output_fields,
timeout=timeout,
**kwargs,
)
# Organize results.
ids = []
documents = []
scores = []
for result in res[0]:
meta = {x: result.entity.get(x) for x in output_fields}
doc = Document(page_content=meta.pop(self._text_field), metadata=meta)
documents.append(doc)
scores.append(result.score)
ids.append(result.id)
vectors = self.col.query(
expr=f"{self._primary_field} in {ids}",
output_fields=[self._primary_field, self._vector_field],
timeout=timeout,
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-17
|
output_fields=[self._primary_field, self._vector_field],
timeout=timeout,
)
# Reorganize the results from query to match search order.
vectors = {x[self._primary_field]: x[self._vector_field] for x in vectors}
ordered_result_embeddings = [vectors[x] for x in ids]
# Get the new order of results.
new_ordering = maximal_marginal_relevance(
np.array(embedding), ordered_result_embeddings, k=k, lambda_mult=lambda_mult
)
# Reorder the values and return.
ret = []
for x in new_ordering:
# Function can return -1 index
if x == -1:
break
else:
ret.append(documents[x])
return ret
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
collection_name: str = "LangChainCollection",
connection_args: dict[str, Any] = DEFAULT_MILVUS_CONNECTION,
consistency_level: str = "Session",
index_params: Optional[dict] = None,
search_params: Optional[dict] = None,
drop_old: bool = False,
**kwargs: Any,
) -> Milvus:
"""Create a Milvus collection, indexes it with HNSW, and insert data.
Args:
texts (List[str]): Text data.
embedding (Embeddings): Embedding function.
metadatas (Optional[List[dict]]): Metadata for each text if it exists.
Defaults to None.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
46ec4d20b726-18
|
Defaults to None.
collection_name (str, optional): Collection name to use. Defaults to
"LangChainCollection".
connection_args (dict[str, Any], optional): Connection args to use. Defaults
to DEFAULT_MILVUS_CONNECTION.
consistency_level (str, optional): Which consistency level to use. Defaults
to "Session".
index_params (Optional[dict], optional): Which index_params to use. Defaults
to None.
search_params (Optional[dict], optional): Which search params to use.
Defaults to None.
drop_old (Optional[bool], optional): Whether to drop the collection with
that name if it exists. Defaults to False.
Returns:
Milvus: Milvus Vector Store
"""
vector_db = cls(
embedding_function=embedding,
collection_name=collection_name,
connection_args=connection_args,
consistency_level=consistency_level,
index_params=index_params,
search_params=search_params,
drop_old=drop_old,
**kwargs,
)
vector_db.add_texts(texts=texts, metadatas=metadatas)
return vector_db
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/milvus.html
|
39ecc05c1952-0
|
Source code for langchain.vectorstores.annoy
"""Wrapper around Annoy vector database."""
from __future__ import annotations
import os
import pickle
import uuid
from configparser import ConfigParser
from pathlib import Path
from typing import Any, Callable, Dict, Iterable, List, Optional, Tuple
import numpy as np
from langchain.docstore.base import Docstore
from langchain.docstore.document import Document
from langchain.docstore.in_memory import InMemoryDocstore
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
from langchain.vectorstores.utils import maximal_marginal_relevance
INDEX_METRICS = frozenset(["angular", "euclidean", "manhattan", "hamming", "dot"])
DEFAULT_METRIC = "angular"
def dependable_annoy_import() -> Any:
"""Import annoy if available, otherwise raise error."""
try:
import annoy
except ImportError:
raise ValueError(
"Could not import annoy python package. "
"Please install it with `pip install --user annoy` "
)
return annoy
[docs]class Annoy(VectorStore):
"""Wrapper around Annoy vector database.
To use, you should have the ``annoy`` python package installed.
Example:
.. code-block:: python
from langchain import Annoy
db = Annoy(embedding_function, index, docstore, index_to_docstore_id)
"""
def __init__(
self,
embedding_function: Callable,
index: Any,
metric: str,
docstore: Docstore,
index_to_docstore_id: Dict[int, str],
):
"""Initialize with necessary components."""
self.embedding_function = embedding_function
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-1
|
):
"""Initialize with necessary components."""
self.embedding_function = embedding_function
self.index = index
self.metric = metric
self.docstore = docstore
self.index_to_docstore_id = index_to_docstore_id
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> List[str]:
raise NotImplementedError(
"Annoy does not allow to add new data once the index is build."
)
[docs] def process_index_results(
self, idxs: List[int], dists: List[float]
) -> List[Tuple[Document, float]]:
"""Turns annoy results into a list of documents and scores.
Args:
idxs: List of indices of the documents in the index.
dists: List of distances of the documents in the index.
Returns:
List of Documents and scores.
"""
docs = []
for idx, dist in zip(idxs, dists):
_id = self.index_to_docstore_id[idx]
doc = self.docstore.search(_id)
if not isinstance(doc, Document):
raise ValueError(f"Could not find document for id {_id}, got {doc}")
docs.append((doc, dist))
return docs
[docs] def similarity_search_with_score_by_vector(
self, embedding: List[float], k: int = 4, search_k: int = -1
) -> List[Tuple[Document, float]]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-2
|
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
search_k: inspect up to search_k nodes which defaults
to n_trees * n if not provided
Returns:
List of Documents most similar to the query and score for each
"""
idxs, dists = self.index.get_nns_by_vector(
embedding, k, search_k=search_k, include_distances=True
)
return self.process_index_results(idxs, dists)
[docs] def similarity_search_with_score_by_index(
self, docstore_index: int, k: int = 4, search_k: int = -1
) -> List[Tuple[Document, float]]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
search_k: inspect up to search_k nodes which defaults
to n_trees * n if not provided
Returns:
List of Documents most similar to the query and score for each
"""
idxs, dists = self.index.get_nns_by_item(
docstore_index, k, search_k=search_k, include_distances=True
)
return self.process_index_results(idxs, dists)
[docs] def similarity_search_with_score(
self, query: str, k: int = 4, search_k: int = -1
) -> List[Tuple[Document, float]]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-3
|
k: Number of Documents to return. Defaults to 4.
search_k: inspect up to search_k nodes which defaults
to n_trees * n if not provided
Returns:
List of Documents most similar to the query and score for each
"""
embedding = self.embedding_function(query)
docs = self.similarity_search_with_score_by_vector(embedding, k, search_k)
return docs
[docs] def similarity_search_by_vector(
self, embedding: List[float], k: int = 4, search_k: int = -1, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to embedding vector.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
search_k: inspect up to search_k nodes which defaults
to n_trees * n if not provided
Returns:
List of Documents most similar to the embedding.
"""
docs_and_scores = self.similarity_search_with_score_by_vector(
embedding, k, search_k
)
return [doc for doc, _ in docs_and_scores]
[docs] def similarity_search_by_index(
self, docstore_index: int, k: int = 4, search_k: int = -1, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to docstore_index.
Args:
docstore_index: Index of document in docstore
k: Number of Documents to return. Defaults to 4.
search_k: inspect up to search_k nodes which defaults
to n_trees * n if not provided
Returns:
List of Documents most similar to the embedding.
"""
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-4
|
Returns:
List of Documents most similar to the embedding.
"""
docs_and_scores = self.similarity_search_with_score_by_index(
docstore_index, k, search_k
)
return [doc for doc, _ in docs_and_scores]
[docs] def similarity_search(
self, query: str, k: int = 4, search_k: int = -1, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
search_k: inspect up to search_k nodes which defaults
to n_trees * n if not provided
Returns:
List of Documents most similar to the query.
"""
docs_and_scores = self.similarity_search_with_score(query, k, search_k)
return [doc for doc, _ in docs_and_scores]
[docs] def max_marginal_relevance_search_by_vector(
self,
embedding: List[float],
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
embedding: Embedding to look up documents similar to.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
k: Number of Documents to return. Defaults to 4.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-5
|
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
idxs = self.index.get_nns_by_vector(
embedding, fetch_k, search_k=-1, include_distances=False
)
embeddings = [self.index.get_item_vector(i) for i in idxs]
mmr_selected = maximal_marginal_relevance(
np.array([embedding], dtype=np.float32),
embeddings,
k=k,
lambda_mult=lambda_mult,
)
# ignore the -1's if not enough docs are returned/indexed
selected_indices = [idxs[i] for i in mmr_selected if i != -1]
docs = []
for i in selected_indices:
_id = self.index_to_docstore_id[i]
doc = self.docstore.search(_id)
if not isinstance(doc, Document):
raise ValueError(f"Could not find document for id {_id}, got {doc}")
docs.append(doc)
return docs
[docs] def max_marginal_relevance_search(
self,
query: str,
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-6
|
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
embedding = self.embedding_function(query)
docs = self.max_marginal_relevance_search_by_vector(
embedding, k, fetch_k, lambda_mult=lambda_mult
)
return docs
@classmethod
def __from(
cls,
texts: List[str],
embeddings: List[List[float]],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
metric: str = DEFAULT_METRIC,
trees: int = 100,
n_jobs: int = -1,
**kwargs: Any,
) -> Annoy:
if metric not in INDEX_METRICS:
raise ValueError(
(
f"Unsupported distance metric: {metric}. "
f"Expected one of {list(INDEX_METRICS)}"
)
)
annoy = dependable_annoy_import()
if not embeddings:
raise ValueError("embeddings must be provided to build AnnoyIndex")
f = len(embeddings[0])
index = annoy.AnnoyIndex(f, metric=metric)
for i, emb in enumerate(embeddings):
index.add_item(i, emb)
index.build(trees, n_jobs=n_jobs)
documents = []
for i, text in enumerate(texts):
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-7
|
documents = []
for i, text in enumerate(texts):
metadata = metadatas[i] if metadatas else {}
documents.append(Document(page_content=text, metadata=metadata))
index_to_id = {i: str(uuid.uuid4()) for i in range(len(documents))}
docstore = InMemoryDocstore(
{index_to_id[i]: doc for i, doc in enumerate(documents)}
)
return cls(embedding.embed_query, index, metric, docstore, index_to_id)
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
metric: str = DEFAULT_METRIC,
trees: int = 100,
n_jobs: int = -1,
**kwargs: Any,
) -> Annoy:
"""Construct Annoy wrapper from raw documents.
Args:
texts: List of documents to index.
embedding: Embedding function to use.
metadatas: List of metadata dictionaries to associate with documents.
metric: Metric to use for indexing. Defaults to "angular".
trees: Number of trees to use for indexing. Defaults to 100.
n_jobs: Number of jobs to use for indexing. Defaults to -1.
This is a user friendly interface that:
1. Embeds documents.
2. Creates an in memory docstore
3. Initializes the Annoy database
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import Annoy
from langchain.embeddings import OpenAIEmbeddings
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-8
|
from langchain import Annoy
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
index = Annoy.from_texts(texts, embeddings)
"""
embeddings = embedding.embed_documents(texts)
return cls.__from(
texts, embeddings, embedding, metadatas, metric, trees, n_jobs, **kwargs
)
[docs] @classmethod
def from_embeddings(
cls,
text_embeddings: List[Tuple[str, List[float]]],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
metric: str = DEFAULT_METRIC,
trees: int = 100,
n_jobs: int = -1,
**kwargs: Any,
) -> Annoy:
"""Construct Annoy wrapper from embeddings.
Args:
text_embeddings: List of tuples of (text, embedding)
embedding: Embedding function to use.
metadatas: List of metadata dictionaries to associate with documents.
metric: Metric to use for indexing. Defaults to "angular".
trees: Number of trees to use for indexing. Defaults to 100.
n_jobs: Number of jobs to use for indexing. Defaults to -1
This is a user friendly interface that:
1. Creates an in memory docstore with provided embeddings
2. Initializes the Annoy database
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import Annoy
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
text_embeddings = embeddings.embed_documents(texts)
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-9
|
embeddings = OpenAIEmbeddings()
text_embeddings = embeddings.embed_documents(texts)
text_embedding_pairs = list(zip(texts, text_embeddings))
db = Annoy.from_embeddings(text_embedding_pairs, embeddings)
"""
texts = [t[0] for t in text_embeddings]
embeddings = [t[1] for t in text_embeddings]
return cls.__from(
texts, embeddings, embedding, metadatas, metric, trees, n_jobs, **kwargs
)
[docs] def save_local(self, folder_path: str, prefault: bool = False) -> None:
"""Save Annoy index, docstore, and index_to_docstore_id to disk.
Args:
folder_path: folder path to save index, docstore,
and index_to_docstore_id to.
prefault: Whether to pre-load the index into memory.
"""
path = Path(folder_path)
os.makedirs(path, exist_ok=True)
# save index, index config, docstore and index_to_docstore_id
config_object = ConfigParser()
config_object["ANNOY"] = {
"f": self.index.f,
"metric": self.metric,
}
self.index.save(str(path / "index.annoy"), prefault=prefault)
with open(path / "index.pkl", "wb") as file:
pickle.dump((self.docstore, self.index_to_docstore_id, config_object), file)
[docs] @classmethod
def load_local(
cls,
folder_path: str,
embeddings: Embeddings,
) -> Annoy:
"""Load Annoy index, docstore, and index_to_docstore_id to disk.
Args:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
39ecc05c1952-10
|
Args:
folder_path: folder path to load index, docstore,
and index_to_docstore_id from.
embeddings: Embeddings to use when generating queries.
"""
path = Path(folder_path)
# load index separately since it is not picklable
annoy = dependable_annoy_import()
# load docstore and index_to_docstore_id
with open(path / "index.pkl", "rb") as file:
docstore, index_to_docstore_id, config_object = pickle.load(file)
f = int(config_object["ANNOY"]["f"])
metric = config_object["ANNOY"]["metric"]
index = annoy.AnnoyIndex(f, metric=metric)
index.load(str(path / "index.annoy"))
return cls(
embeddings.embed_query, index, metric, docstore, index_to_docstore_id
)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/annoy.html
|
bde48b47f63a-0
|
Source code for langchain.vectorstores.weaviate
"""Wrapper around weaviate vector database."""
from __future__ import annotations
from typing import Any, Dict, Iterable, List, Optional, Type
from uuid import uuid4
import numpy as np
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.utils import get_from_dict_or_env
from langchain.vectorstores.base import VectorStore
from langchain.vectorstores.utils import maximal_marginal_relevance
def _default_schema(index_name: str) -> Dict:
return {
"class": index_name,
"properties": [
{
"name": "text",
"dataType": ["text"],
}
],
}
def _create_weaviate_client(**kwargs: Any) -> Any:
client = kwargs.get("client")
if client is not None:
return client
weaviate_url = get_from_dict_or_env(kwargs, "weaviate_url", "WEAVIATE_URL")
weaviate_api_key = get_from_dict_or_env(
kwargs, "weaviate_api_key", "WEAVIATE_API_KEY", None
)
try:
import weaviate
except ImportError:
raise ValueError(
"Could not import weaviate python package. "
"Please install it with `pip instal weaviate-client`"
)
auth = (
weaviate.auth.AuthApiKey(api_key=weaviate_api_key)
if weaviate_api_key is not None
else None
)
client = weaviate.Client(weaviate_url, auth_client_secret=auth)
return client
[docs]class Weaviate(VectorStore):
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
bde48b47f63a-1
|
return client
[docs]class Weaviate(VectorStore):
"""Wrapper around Weaviate vector database.
To use, you should have the ``weaviate-client`` python package installed.
Example:
.. code-block:: python
import weaviate
from langchain.vectorstores import Weaviate
client = weaviate.Client(url=os.environ["WEAVIATE_URL"], ...)
weaviate = Weaviate(client, index_name, text_key)
"""
def __init__(
self,
client: Any,
index_name: str,
text_key: str,
embedding: Optional[Embeddings] = None,
attributes: Optional[List[str]] = None,
):
"""Initialize with Weaviate client."""
try:
import weaviate
except ImportError:
raise ValueError(
"Could not import weaviate python package. "
"Please install it with `pip install weaviate-client`."
)
if not isinstance(client, weaviate.Client):
raise ValueError(
f"client should be an instance of weaviate.Client, got {type(client)}"
)
self._client = client
self._index_name = index_name
self._embedding = embedding
self._text_key = text_key
self._query_attrs = [self._text_key]
if attributes is not None:
self._query_attrs.extend(attributes)
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> List[str]:
"""Upload texts with metadata (properties) to Weaviate."""
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
bde48b47f63a-2
|
"""Upload texts with metadata (properties) to Weaviate."""
from weaviate.util import get_valid_uuid
with self._client.batch as batch:
ids = []
for i, doc in enumerate(texts):
data_properties = {
self._text_key: doc,
}
if metadatas is not None:
for key in metadatas[i].keys():
data_properties[key] = metadatas[i][key]
_id = get_valid_uuid(uuid4())
batch.add_data_object(
data_object=data_properties, class_name=self._index_name, uuid=_id
)
ids.append(_id)
return ids
[docs] def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query.
"""
content: Dict[str, Any] = {"concepts": [query]}
if kwargs.get("search_distance"):
content["certainty"] = kwargs.get("search_distance")
query_obj = self._client.query.get(self._index_name, self._query_attrs)
if kwargs.get("where_filter"):
query_obj = query_obj.with_where(kwargs.get("where_filter"))
result = query_obj.with_near_text(content).with_limit(k).do()
if "errors" in result:
raise ValueError(f"Error during query: {result['errors']}")
docs = []
for res in result["data"]["Get"][self._index_name]:
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
bde48b47f63a-3
|
docs = []
for res in result["data"]["Get"][self._index_name]:
text = res.pop(self._text_key)
docs.append(Document(page_content=text, metadata=res))
return docs
[docs] def similarity_search_by_vector(
self, embedding: List[float], k: int = 4, **kwargs: Any
) -> List[Document]:
"""Look up similar documents by embedding vector in Weaviate."""
vector = {"vector": embedding}
query_obj = self._client.query.get(self._index_name, self._query_attrs)
if kwargs.get("where_filter"):
query_obj = query_obj.with_where(kwargs.get("where_filter"))
result = query_obj.with_near_vector(vector).with_limit(k).do()
if "errors" in result:
raise ValueError(f"Error during query: {result['errors']}")
docs = []
for res in result["data"]["Get"][self._index_name]:
text = res.pop(self._text_key)
docs.append(Document(page_content=text, metadata=res))
return docs
[docs] def max_marginal_relevance_search(
self,
query: str,
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
bde48b47f63a-4
|
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
if self._embedding is not None:
embedding = self._embedding.embed_query(query)
else:
raise ValueError(
"max_marginal_relevance_search requires a suitable Embeddings object"
)
return self.max_marginal_relevance_search_by_vector(
embedding, k=k, fetch_k=fetch_k, lambda_mult=lambda_mult, **kwargs
)
[docs] def max_marginal_relevance_search_by_vector(
self,
embedding: List[float],
k: int = 4,
fetch_k: int = 20,
lambda_mult: float = 0.5,
**kwargs: Any,
) -> List[Document]:
"""Return docs selected using the maximal marginal relevance.
Maximal marginal relevance optimizes for similarity to query AND diversity
among selected documents.
Args:
embedding: Embedding to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
lambda_mult: Number between 0 and 1 that determines the degree
of diversity among the results with 0 corresponding
to maximum diversity and 1 to minimum diversity.
Defaults to 0.5.
Returns:
List of Documents selected by maximal marginal relevance.
"""
vector = {"vector": embedding}
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
bde48b47f63a-5
|
"""
vector = {"vector": embedding}
query_obj = self._client.query.get(self._index_name, self._query_attrs)
if kwargs.get("where_filter"):
query_obj = query_obj.with_where(kwargs.get("where_filter"))
results = (
query_obj.with_additional("vector")
.with_near_vector(vector)
.with_limit(fetch_k)
.do()
)
payload = results["data"]["Get"][self._index_name]
embeddings = [result["_additional"]["vector"] for result in payload]
mmr_selected = maximal_marginal_relevance(
np.array(embedding), embeddings, k=k, lambda_mult=lambda_mult
)
docs = []
for idx in mmr_selected:
text = payload[idx].pop(self._text_key)
payload[idx].pop("_additional")
meta = payload[idx]
docs.append(Document(page_content=text, metadata=meta))
return docs
[docs] @classmethod
def from_texts(
cls: Type[Weaviate],
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> Weaviate:
"""Construct Weaviate wrapper from raw documents.
This is a user-friendly interface that:
1. Embeds documents.
2. Creates a new index for the embeddings in the Weaviate instance.
3. Adds the documents to the newly created Weaviate index.
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain.vectorstores.weaviate import Weaviate
from langchain.embeddings import OpenAIEmbeddings
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
bde48b47f63a-6
|
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
weaviate = Weaviate.from_texts(
texts,
embeddings,
weaviate_url="http://localhost:8080"
)
"""
client = _create_weaviate_client(**kwargs)
from weaviate.util import get_valid_uuid
index_name = kwargs.get("index_name", f"LangChain_{uuid4().hex}")
embeddings = embedding.embed_documents(texts) if embedding else None
text_key = "text"
schema = _default_schema(index_name)
attributes = list(metadatas[0].keys()) if metadatas else None
# check whether the index already exists
if not client.schema.contains(schema):
client.schema.create_class(schema)
with client.batch as batch:
for i, text in enumerate(texts):
data_properties = {
text_key: text,
}
if metadatas is not None:
for key in metadatas[i].keys():
data_properties[key] = metadatas[i][key]
_id = get_valid_uuid(uuid4())
# if an embedding strategy is not provided, we let
# weaviate create the embedding. Note that this will only
# work if weaviate has been installed with a vectorizer module
# like text2vec-contextionary for example
params = {
"uuid": _id,
"data_object": data_properties,
"class_name": index_name,
}
if embeddings is not None:
params["vector"] = embeddings[i]
batch.add_data_object(**params)
batch.flush()
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/weaviate.html
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.