Source code for langchain_community.vectorstores.vikingdb

from __future__ import annotations

import logging
import uuid
from typing import Any, List, Optional, Tuple

import numpy as np
from langchain_core.documents import Document
from langchain_core.embeddings import Embeddings
from langchain_core.vectorstores import VectorStore

from langchain_community.vectorstores.utils import maximal_marginal_relevance

logger = logging.getLogger(__name__)


[docs] class VikingDBConfig(object): """vikingdb connection config See the following documentation for details: https://www.volcengine.com/docs/6459/1167770 Attribute: host(str):The access address of the vector database server that the client needs to connect to. region(str):"cn-shanghai" or "cn-beijing" ak(str):Access Key ID, security credentials for accessing Volcano Engine services. sk(str):Secret Access Key, security credentials for accessing Volcano Engine services. scheme(str):http or https, defaulting to http. """
[docs] def __init__(self, host="host", region="region", ak="ak", sk="sk", scheme="http"): # type: ignore[no-untyped-def] self.host = host self.region = region self.ak = ak self.sk = sk self.scheme = scheme
[docs] class VikingDB(VectorStore): """vikingdb as a vector store In order to use this you need to have a database instance. See the following documentation for details: https://www.volcengine.com/docs/6459/1167774 """
[docs] def __init__( self, embedding_function: Embeddings, collection_name: str = "LangChainCollection", connection_args: Optional[VikingDBConfig] = None, index_params: Optional[dict] = None, drop_old: Optional[bool] = False, **kwargs: Any, ): try: from volcengine.viking_db import Collection, VikingDBService except ImportError: raise ImportError( "Could not import volcengine python package. " "Please install it with `pip install --upgrade volcengine`." ) self.embedding_func = embedding_function self.collection_name = collection_name self.index_name = "LangChainIndex" self.connection_args = connection_args self.index_params = index_params self.drop_old = drop_old self.service = VikingDBService( connection_args.host, # type: ignore[union-attr] connection_args.region, # type: ignore[union-attr] connection_args.ak, # type: ignore[union-attr] connection_args.sk, # type: ignore[union-attr] connection_args.scheme, # type: ignore[union-attr] ) try: col = self.service.get_collection(collection_name) except Exception: col = None self.collection = col self.index = None if self.collection is not None: self.index = self.service.get_index(self.collection_name, self.index_name) if drop_old and isinstance(self.collection, Collection): indexes = self.service.list_indexes(collection_name) for index in indexes: self.service.drop_index(collection_name, index.index_name) self.service.drop_collection(collection_name) self.collection = None self.index = None
@property def embeddings(self) -> Embeddings: return self.embedding_func def _create_collection( self, embeddings: List, metadatas: Optional[List[dict]] = None ) -> None: try: from volcengine.viking_db import Field, FieldType except ImportError: raise ImportError( "Could not import volcengine python package. " "Please install it with `pip install --upgrade volcengine`." ) dim = len(embeddings[0]) fields = [] if metadatas: for key, value in metadatas[0].items(): # print(key, value) if isinstance(value, str): fields.append(Field(key, FieldType.String)) elif isinstance(value, int): fields.append(Field(key, FieldType.Int64)) elif isinstance(value, bool): fields.append(Field(key, FieldType.Bool)) elif isinstance(value, list) and all( isinstance(item, str) for item in value ): fields.append(Field(key, FieldType.List_String)) elif isinstance(value, list) and all( isinstance(item, int) for item in value ): fields.append(Field(key, FieldType.List_Int64)) elif isinstance(value, bytes): fields.append(Field(key, FieldType.Text)) else: raise ValueError( "metadatas value is invalid" "please change the type of metadatas." ) # fields.append(Field("text", FieldType.String)) fields.append(Field("text", FieldType.Text)) fields.append(Field("primary_key", FieldType.String, is_primary_key=True)) fields.append(Field("vector", FieldType.Vector, dim=dim)) self.collection = self.service.create_collection(self.collection_name, fields) def _create_index(self) -> None: try: from volcengine.viking_db import VectorIndexParams except ImportError: raise ImportError( "Could not import volcengine python package. " "Please install it with `pip install --upgrade volcengine`." ) cpu_quota = 2 vector_index = VectorIndexParams() partition_by = "" scalar_index = None if self.index_params is not None: if self.index_params.get("cpu_quota") is not None: cpu_quota = self.index_params["cpu_quota"] if self.index_params.get("vector_index") is not None: vector_index = self.index_params["vector_index"] if self.index_params.get("partition_by") is not None: partition_by = self.index_params["partition_by"] if self.index_params.get("scalar_index") is not None: scalar_index = self.index_params["scalar_index"] self.index = self.service.create_index( self.collection_name, self.index_name, vector_index=vector_index, cpu_quota=cpu_quota, partition_by=partition_by, scalar_index=scalar_index, )
[docs] def add_texts( # type: ignore[override] self, texts: List[str], metadatas: Optional[List[dict]] = None, batch_size: int = 1000, **kwargs: Any, ) -> List[str]: """Insert text data into VikingDB.""" try: from volcengine.viking_db import Data except ImportError: raise ImportError( "Could not import volcengine python package. " "Please install it with `pip install --upgrade volcengine`." ) 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 self.collection is None: self._create_collection(embeddings, metadatas) self._create_index() # insert data data = [] pks: List[str] = [] for index in range(len(embeddings)): primary_key = str(uuid.uuid4()) pks.append(primary_key) field = { "text": texts[index], "primary_key": primary_key, "vector": embeddings[index], } if metadatas is not None and index < len(metadatas): names = list(metadatas[index].keys()) for name in names: field[name] = metadatas[index].get(name) # type: ignore[assignment] data.append(Data(field)) total_count = len(data) for i in range(0, total_count, batch_size): end = min(i + batch_size, total_count) insert_data = data[i:end] # print(insert_data) self.collection.upsert_data(insert_data) # type: ignore[union-attr] return pks
[docs] def similarity_search_with_score( self, query: str, params: Optional[dict] = None, **kwargs: Any, ) -> List[Tuple[Document, float]]: """Perform a search on a query string and return results with score.""" embedding = self.embedding_func.embed_query(query) res = self.similarity_search_with_score_by_vector( embedding=embedding, params=params, **kwargs ) return res
[docs] def similarity_search_by_vector( # type: ignore[override] self, embedding: List[float], params: Optional[dict] = None, **kwargs: Any, ) -> List[Document]: """Perform a similarity search against the query string.""" res = self.similarity_search_with_score_by_vector( embedding=embedding, params=params, **kwargs ) return [doc for doc, _ in res]
[docs] def similarity_search_with_score_by_vector( self, embedding: List[float], params: Optional[dict] = None, **kwargs: Any, ) -> List[Tuple[Document, float]]: """Perform a search on a query string and return results with score.""" if self.collection is None: logger.debug("No existing collection to search.") return [] filter = None limit = 10 output_fields = None partition = "default" if params is not None: if params.get("filter") is not None: filter = params["filter"] if params.get("limit") is not None: limit = params["limit"] if params.get("output_fields") is not None: output_fields = params["output_fields"] if params.get("partition") is not None: partition = params["partition"] res = self.index.search_by_vector( # type: ignore[union-attr] embedding, filter=filter, limit=limit, output_fields=output_fields, partition=partition, ) ret = [] for item in res: if "primary_key" in item.fields: item.fields.pop("primary_key") if "vector" in item.fields: item.fields.pop("vector") page_content = "" if "text" in item.fields: page_content = item.fields.pop("text") doc = Document(page_content=page_content, metadata=item.fields) pair = (doc, item.score) ret.append(pair) return ret
[docs] def max_marginal_relevance_search_by_vector( # type: ignore[override] self, embedding: List[float], k: int = 4, lambda_mult: float = 0.5, params: Optional[dict] = None, **kwargs: Any, ) -> List[Document]: """Perform a search and return results that are reordered by MMR.""" if self.collection is None: logger.debug("No existing collection to search.") return [] filter = None limit = 10 output_fields = None partition = "default" if params is not None: if params.get("filter") is not None: filter = params["filter"] if params.get("limit") is not None: limit = params["limit"] if params.get("output_fields") is not None: output_fields = params["output_fields"] if params.get("partition") is not None: partition = params["partition"] res = self.index.search_by_vector( # type: ignore[union-attr] embedding, filter=filter, limit=limit, output_fields=output_fields, partition=partition, ) documents = [] ordered_result_embeddings = [] for item in res: if ( "vector" not in item.fields or "primary_key" not in item.fields or "text" not in item.fields ): continue ordered_result_embeddings.append(item.fields.pop("vector")) item.fields.pop("primary_key") page_content = item.fields.pop("text") doc = Document(page_content=page_content, metadata=item.fields) documents.append(doc) 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] def delete( self, ids: Optional[List[str]] = None, **kwargs: Any, ) -> None: if self.collection is None: logger.debug("No existing collection to search.") self.collection.delete_data(ids) # type: ignore[union-attr]
[docs] @classmethod def from_texts( # type: ignore[no-untyped-def, override] cls, texts: List[str], embedding: Embeddings, connection_args: Optional[VikingDBConfig] = None, metadatas: Optional[List[dict]] = None, collection_name: str = "LangChainCollection", index_params: Optional[dict] = None, drop_old: bool = False, **kwargs: Any, ): """Create a collection, indexes it and insert data.""" if connection_args is None: raise Exception("VikingDBConfig does not exists") vector_db = cls( embedding_function=embedding, collection_name=collection_name, connection_args=connection_args, index_params=index_params, drop_old=drop_old, **kwargs, ) vector_db.add_texts(texts=texts, metadatas=metadatas) return vector_db