viruPVS/langchain-docs huggingface dataset:
Source code for langchain_community.vectorstores.milvus
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_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__)
DEFAULT_MILVUS_CONNECTION = {
    "host": "localhost",
    "port": "19530",
    "user": "",
    "password": "",
    "secure": False,
}
[docs]class Milvus(VectorStore):
    """`Milvus` vector store.
    You need to install `pymilvus` and run Milvus.
    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 look at this documentation:
    https://zilliz.com/cloud and make use of the Zilliz vectorstore found in
    this project.
    IF USING L2/IP metric, IT IS HIGHLY SUGGESTED TO NORMALIZE YOUR DATA.
    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 connection args used for
            this class comes in the form of a dict.
        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
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.
        primary_field (str): Name of the primary key field. Defaults to "pk".
        text_field (str): Name of the text field. Defaults to "text".
        vector_field (str): Name of the vector field. Defaults to "vector".
    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.
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.
    Example:
        .. code-block:: python
        from langchain_community.vectorstores import Milvus
        from langchain_community.embeddings import OpenAIEmbeddings
        embedding = OpenAIEmbeddings()
        # Connect to a milvus instance on localhost
        milvus_store = Milvus(
            embedding_function = Embeddings,
            collection_name = "LangChainCollection",
            drop_old = True,
        )
    Raises:
        ValueError: If the pymilvus python package is not installed.
    """
[docs]    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,
        *,
        primary_field: str = "pk",
        text_field: str = "text",
        vector_field: str = "vector",
    ):
vector_field: str = "vector",
    ):
        """Initialize the Milvus vector store."""
        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}},
            "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.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 = primary_field
        # In order for compatibility, the text field will need to be called "text"
        self._text_field = text_field
        # In order for compatibility, the vector field needs to be called "vector"
        self._vector_field = vector_field
        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 collection 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):
            self.col.drop()
            self.col = None
        # Initialize the vector store
        self._init()
    @property
    def embeddings(self) -> Embeddings:
        return self.embedding_func
    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)
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 attempt")
        # 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)
                ):
                    logger.debug("Using previous connection: %s", con[0])
                    return con[0]
        # Generate a new connection if one doesn't 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(
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 isn't 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(
# 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:
                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
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(
                    "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:
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.
        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.
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 hasn't 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:
                        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
# 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.
            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]
)
        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(
            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.
"""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 to 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)
        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