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batch.add_data_object(**params)
batch.flush()
return cls(client, index_name, text_key, embedding, attributes)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
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Source code for langchain.vectorstores.myscale
"""Wrapper around MyScale vector database."""
from __future__ import annotations
import json
import logging
from hashlib import sha1
from threading import Thread
from typing import Any, Dict, Iterable, List, Optional, Tuple
from pydantic import BaseSettings
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
logger = logging.getLogger()
def has_mul_sub_str(s: str, *args: Any) -> bool:
for a in args:
if a not in s:
return False
return True
[docs]class MyScaleSettings(BaseSettings):
"""MyScale Client Configuration
Attribute:
myscale_host (str) : An URL to connect to MyScale backend.
Defaults to 'localhost'.
myscale_port (int) : URL port to connect with HTTP. Defaults to 8443.
username (str) : Usernamed to login. Defaults to None.
password (str) : Password to login. Defaults to None.
index_type (str): index type string.
index_param (dict): index build parameter.
database (str) : Database name to find the table. Defaults to 'default'.
table (str) : Table name to operate on.
Defaults to 'vector_table'.
metric (str) : Metric to compute distance,
supported are ('l2', 'cosine', 'ip'). Defaults to 'cosine'.
column_map (Dict) : Column type map to project column name onto langchain
semantics. Must have keys: `text`, `id`, `vector`,
must be same size to number of columns. For example:
.. code-block:: python
{
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.. code-block:: python
{
'id': 'text_id',
'vector': 'text_embedding',
'text': 'text_plain',
'metadata': 'metadata_dictionary_in_json',
}
Defaults to identity map.
"""
host: str = "localhost"
port: int = 8443
username: Optional[str] = None
password: Optional[str] = None
index_type: str = "IVFFLAT"
index_param: Optional[Dict[str, str]] = None
column_map: Dict[str, str] = {
"id": "id",
"text": "text",
"vector": "vector",
"metadata": "metadata",
}
database: str = "default"
table: str = "langchain"
metric: str = "cosine"
def __getitem__(self, item: str) -> Any:
return getattr(self, item)
class Config:
env_file = ".env"
env_prefix = "myscale_"
env_file_encoding = "utf-8"
[docs]class MyScale(VectorStore):
"""Wrapper around MyScale vector database
You need a `clickhouse-connect` python package, and a valid account
to connect to MyScale.
MyScale can not only search with simple vector indexes,
it also supports complex query with multiple conditions,
constraints and even sub-queries.
For more information, please visit
[myscale official site](https://docs.myscale.com/en/overview/)
"""
def __init__(
self,
embedding: Embeddings,
config: Optional[MyScaleSettings] = None,
**kwargs: Any,
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config: Optional[MyScaleSettings] = None,
**kwargs: Any,
) -> None:
"""MyScale Wrapper to LangChain
embedding_function (Embeddings):
config (MyScaleSettings): Configuration to MyScale Client
Other keyword arguments will pass into
[clickhouse-connect](https://docs.myscale.com/)
"""
try:
from clickhouse_connect import get_client
except ImportError:
raise ValueError(
"Could not import clickhouse connect python package. "
"Please install it with `pip install clickhouse-connect`."
)
try:
from tqdm import tqdm
self.pgbar = tqdm
except ImportError:
# Just in case if tqdm is not installed
self.pgbar = lambda x: x
super().__init__()
if config is not None:
self.config = config
else:
self.config = MyScaleSettings()
assert self.config
assert self.config.host and self.config.port
assert (
self.config.column_map
and self.config.database
and self.config.table
and self.config.metric
)
for k in ["id", "vector", "text", "metadata"]:
assert k in self.config.column_map
assert self.config.metric in ["ip", "cosine", "l2"]
# initialize the schema
dim = len(embedding.embed_query("try this out"))
index_params = (
", " + ",".join([f"'{k}={v}'" for k, v in self.config.index_param.items()])
if self.config.index_param
else ""
)
schema_ = f"""
CREATE TABLE IF NOT EXISTS {self.config.database}.{self.config.table}(
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CREATE TABLE IF NOT EXISTS {self.config.database}.{self.config.table}(
{self.config.column_map['id']} String,
{self.config.column_map['text']} String,
{self.config.column_map['vector']} Array(Float32),
{self.config.column_map['metadata']} JSON,
CONSTRAINT cons_vec_len CHECK length(\
{self.config.column_map['vector']}) = {dim},
VECTOR INDEX vidx {self.config.column_map['vector']} \
TYPE {self.config.index_type}(\
'metric_type={self.config.metric}'{index_params})
) ENGINE = MergeTree ORDER BY {self.config.column_map['id']}
"""
self.dim = dim
self.BS = "\\"
self.must_escape = ("\\", "'")
self.embedding_function = embedding.embed_query
self.dist_order = "ASC" if self.config.metric in ["cosine", "l2"] else "DESC"
# Create a connection to myscale
self.client = get_client(
host=self.config.host,
port=self.config.port,
username=self.config.username,
password=self.config.password,
**kwargs,
)
self.client.command("SET allow_experimental_object_type=1")
self.client.command(schema_)
[docs] def escape_str(self, value: str) -> str:
return "".join(f"{self.BS}{c}" if c in self.must_escape else c for c in value)
def _build_istr(self, transac: Iterable, column_names: Iterable[str]) -> str:
ks = ",".join(column_names)
_data = []
for n in transac:
n = ",".join([f"'{self.escape_str(str(_n))}'" for _n in n])
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_data.append(f"({n})")
i_str = f"""
INSERT INTO TABLE
{self.config.database}.{self.config.table}({ks})
VALUES
{','.join(_data)}
"""
return i_str
def _insert(self, transac: Iterable, column_names: Iterable[str]) -> None:
_i_str = self._build_istr(transac, column_names)
self.client.command(_i_str)
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
batch_size: int = 32,
ids: Optional[Iterable[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.
ids: Optional list of ids to associate with the texts.
batch_size: Batch size of insertion
metadata: Optional column data to be inserted
Returns:
List of ids from adding the texts into the vectorstore.
"""
# Embed and create the documents
ids = ids or [sha1(t.encode("utf-8")).hexdigest() for t in texts]
colmap_ = self.config.column_map
transac = []
column_names = {
colmap_["id"]: ids,
colmap_["text"]: texts,
colmap_["vector"]: map(self.embedding_function, texts),
}
metadatas = metadatas or [{} for _ in texts]
column_names[colmap_["metadata"]] = map(json.dumps, metadatas)
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column_names[colmap_["metadata"]] = map(json.dumps, metadatas)
assert len(set(colmap_) - set(column_names)) >= 0
keys, values = zip(*column_names.items())
try:
t = None
for v in self.pgbar(
zip(*values), desc="Inserting data...", total=len(metadatas)
):
assert len(v[keys.index(self.config.column_map["vector"])]) == self.dim
transac.append(v)
if len(transac) == batch_size:
if t:
t.join()
t = Thread(target=self._insert, args=[transac, keys])
t.start()
transac = []
if len(transac) > 0:
if t:
t.join()
self._insert(transac, keys)
return [i for i in ids]
except Exception as e:
logger.error(f"\033[91m\033[1m{type(e)}\033[0m \033[95m{str(e)}\033[0m")
return []
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[Dict[Any, Any]]] = None,
config: Optional[MyScaleSettings] = None,
text_ids: Optional[Iterable[str]] = None,
batch_size: int = 32,
**kwargs: Any,
) -> MyScale:
"""Create Myscale wrapper with existing texts
Args:
embedding_function (Embeddings): Function to extract text embedding
texts (Iterable[str]): List or tuple of strings to be added
|
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texts (Iterable[str]): List or tuple of strings to be added
config (MyScaleSettings, Optional): Myscale configuration
text_ids (Optional[Iterable], optional): IDs for the texts.
Defaults to None.
batch_size (int, optional): Batchsize when transmitting data to MyScale.
Defaults to 32.
metadata (List[dict], optional): metadata to texts. Defaults to None.
Other keyword arguments will pass into
[clickhouse-connect](https://clickhouse.com/docs/en/integrations/python#clickhouse-connect-driver-api)
Returns:
MyScale Index
"""
ctx = cls(embedding, config, **kwargs)
ctx.add_texts(texts, ids=text_ids, batch_size=batch_size, metadatas=metadatas)
return ctx
def __repr__(self) -> str:
"""Text representation for myscale, prints backends, username and schemas.
Easy to use with `str(Myscale())`
Returns:
repr: string to show connection info and data schema
"""
_repr = f"\033[92m\033[1m{self.config.database}.{self.config.table} @ "
_repr += f"{self.config.host}:{self.config.port}\033[0m\n\n"
_repr += f"\033[1musername: {self.config.username}\033[0m\n\nTable Schema:\n"
_repr += "-" * 51 + "\n"
for r in self.client.query(
f"DESC {self.config.database}.{self.config.table}"
).named_results():
_repr += (
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|
).named_results():
_repr += (
f"|\033[94m{r['name']:24s}\033[0m|\033[96m{r['type']:24s}\033[0m|\n"
)
_repr += "-" * 51 + "\n"
return _repr
def _build_qstr(
self, q_emb: List[float], topk: int, where_str: Optional[str] = None
) -> str:
q_emb_str = ",".join(map(str, q_emb))
if where_str:
where_str = f"PREWHERE {where_str}"
else:
where_str = ""
q_str = f"""
SELECT {self.config.column_map['text']},
{self.config.column_map['metadata']}, dist
FROM {self.config.database}.{self.config.table}
{where_str}
ORDER BY distance({self.config.column_map['vector']}, [{q_emb_str}])
AS dist {self.dist_order}
LIMIT {topk}
"""
return q_str
[docs] def similarity_search(
self, query: str, k: int = 4, where_str: Optional[str] = None, **kwargs: Any
) -> List[Document]:
"""Perform a similarity search with MyScale
Args:
query (str): query string
k (int, optional): Top K neighbors to retrieve. Defaults to 4.
where_str (Optional[str], optional): where condition string.
Defaults to None.
NOTE: Please do not let end-user to fill this and always be aware
of SQL injection. When dealing with metadatas, remember to
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|
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|
of SQL injection. When dealing with metadatas, remember to
use `{self.metadata_column}.attribute` instead of `attribute`
alone. The default name for it is `metadata`.
Returns:
List[Document]: List of Documents
"""
return self.similarity_search_by_vector(
self.embedding_function(query), k, where_str, **kwargs
)
[docs] def similarity_search_by_vector(
self,
embedding: List[float],
k: int = 4,
where_str: Optional[str] = None,
**kwargs: Any,
) -> List[Document]:
"""Perform a similarity search with MyScale by vectors
Args:
query (str): query string
k (int, optional): Top K neighbors to retrieve. Defaults to 4.
where_str (Optional[str], optional): where condition string.
Defaults to None.
NOTE: Please do not let end-user to fill this and always be aware
of SQL injection. When dealing with metadatas, remember to
use `{self.metadata_column}.attribute` instead of `attribute`
alone. The default name for it is `metadata`.
Returns:
List[Document]: List of (Document, similarity)
"""
q_str = self._build_qstr(embedding, k, where_str)
try:
return [
Document(
page_content=r[self.config.column_map["text"]],
metadata=r[self.config.column_map["metadata"]],
)
for r in self.client.query(q_str).named_results()
]
except Exception as e:
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|
]
except Exception as e:
logger.error(f"\033[91m\033[1m{type(e)}\033[0m \033[95m{str(e)}\033[0m")
return []
[docs] def similarity_search_with_relevance_scores(
self, query: str, k: int = 4, where_str: Optional[str] = None, **kwargs: Any
) -> List[Tuple[Document, float]]:
"""Perform a similarity search with MyScale
Args:
query (str): query string
k (int, optional): Top K neighbors to retrieve. Defaults to 4.
where_str (Optional[str], optional): where condition string.
Defaults to None.
NOTE: Please do not let end-user to fill this and always be aware
of SQL injection. When dealing with metadatas, remember to
use `{self.metadata_column}.attribute` instead of `attribute`
alone. The default name for it is `metadata`.
Returns:
List[Document]: List of documents
"""
q_str = self._build_qstr(self.embedding_function(query), k, where_str)
try:
return [
(
Document(
page_content=r[self.config.column_map["text"]],
metadata=r[self.config.column_map["metadata"]],
),
r["dist"],
)
for r in self.client.query(q_str).named_results()
]
except Exception as e:
logger.error(f"\033[91m\033[1m{type(e)}\033[0m \033[95m{str(e)}\033[0m")
return []
[docs] def drop(self) -> None:
"""
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return []
[docs] def drop(self) -> None:
"""
Helper function: Drop data
"""
self.client.command(
f"DROP TABLE IF EXISTS {self.config.database}.{self.config.table}"
)
@property
def metadata_column(self) -> str:
return self.config.column_map["metadata"]
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
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|
Source code for langchain.vectorstores.base
"""Interface for vector stores."""
from __future__ import annotations
import asyncio
from abc import ABC, abstractmethod
from functools import partial
from typing import Any, Dict, Iterable, List, Optional, Tuple, Type, TypeVar
from pydantic import BaseModel, Field, root_validator
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.schema import BaseRetriever
VST = TypeVar("VST", bound="VectorStore")
[docs]class VectorStore(ABC):
"""Interface for vector stores."""
[docs] @abstractmethod
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.
kwargs: vectorstore specific parameters
Returns:
List of ids from adding the texts into the vectorstore.
"""
[docs] async def aadd_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."""
raise NotImplementedError
[docs] def add_documents(self, documents: List[Document], **kwargs: Any) -> List[str]:
"""Run more documents through the embeddings and add to the vectorstore.
Args:
documents (List[Document]: Documents to add to the vectorstore.
Returns:
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documents (List[Document]: Documents to add to the vectorstore.
Returns:
List[str]: List of IDs of the added texts.
"""
# TODO: Handle the case where the user doesn't provide ids on the Collection
texts = [doc.page_content for doc in documents]
metadatas = [doc.metadata for doc in documents]
return self.add_texts(texts, metadatas, **kwargs)
[docs] async def aadd_documents(
self, documents: List[Document], **kwargs: Any
) -> List[str]:
"""Run more documents through the embeddings and add to the vectorstore.
Args:
documents (List[Document]: Documents to add to the vectorstore.
Returns:
List[str]: List of IDs of the added texts.
"""
texts = [doc.page_content for doc in documents]
metadatas = [doc.metadata for doc in documents]
return await self.aadd_texts(texts, metadatas, **kwargs)
[docs] @abstractmethod
def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query."""
[docs] def similarity_search_with_relevance_scores(
self,
query: str,
k: int = 4,
**kwargs: Any,
) -> List[Tuple[Document, float]]:
"""Return docs and relevance scores in the range [0, 1].
0 is dissimilar, 1 is most similar.
"""
docs_and_similarities = self._similarity_search_with_relevance_scores(
query, k=k, **kwargs
)
if any(
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query, k=k, **kwargs
)
if any(
similarity < 0.0 or similarity > 1.0
for _, similarity in docs_and_similarities
):
raise ValueError(
"Relevance scores must be between"
f" 0 and 1, got {docs_and_similarities}"
)
return docs_and_similarities
def _similarity_search_with_relevance_scores(
self,
query: str,
k: int = 4,
**kwargs: Any,
) -> List[Tuple[Document, float]]:
"""Return docs and relevance scores, normalized on a scale from 0 to 1.
0 is dissimilar, 1 is most similar.
"""
raise NotImplementedError
[docs] async def asimilarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query."""
# This is a temporary workaround to make the similarity search
# asynchronous. The proper solution is to make the similarity search
# asynchronous in the vector store implementations.
func = partial(self.similarity_search, query, k, **kwargs)
return await asyncio.get_event_loop().run_in_executor(None, func)
[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 query vector.
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Returns:
List of Documents most similar to the query vector.
"""
raise NotImplementedError
[docs] async def asimilarity_search_by_vector(
self, embedding: List[float], k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to embedding vector."""
# This is a temporary workaround to make the similarity search
# asynchronous. The proper solution is to make the similarity search
# asynchronous in the vector store implementations.
func = partial(self.similarity_search_by_vector, embedding, k, **kwargs)
return await asyncio.get_event_loop().run_in_executor(None, func)
[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.
"""
raise NotImplementedError
[docs] async def amax_marginal_relevance_search(
self,
query: str,
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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."""
# This is a temporary workaround to make the similarity search
# asynchronous. The proper solution is to make the similarity search
# asynchronous in the vector store implementations.
func = partial(
self.max_marginal_relevance_search, query, k, fetch_k, lambda_mult, **kwargs
)
return await asyncio.get_event_loop().run_in_executor(None, func)
[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.
"""
raise NotImplementedError
[docs] async def amax_marginal_relevance_search_by_vector(
self,
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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."""
raise NotImplementedError
[docs] @classmethod
def from_documents(
cls: Type[VST],
documents: List[Document],
embedding: Embeddings,
**kwargs: Any,
) -> VST:
"""Return VectorStore initialized from documents and embeddings."""
texts = [d.page_content for d in documents]
metadatas = [d.metadata for d in documents]
return cls.from_texts(texts, embedding, metadatas=metadatas, **kwargs)
[docs] @classmethod
async def afrom_documents(
cls: Type[VST],
documents: List[Document],
embedding: Embeddings,
**kwargs: Any,
) -> VST:
"""Return VectorStore initialized from documents and embeddings."""
texts = [d.page_content for d in documents]
metadatas = [d.metadata for d in documents]
return await cls.afrom_texts(texts, embedding, metadatas=metadatas, **kwargs)
[docs] @classmethod
@abstractmethod
def from_texts(
cls: Type[VST],
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> VST:
"""Return VectorStore initialized from texts and embeddings."""
[docs] @classmethod
async def afrom_texts(
cls: Type[VST],
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async def afrom_texts(
cls: Type[VST],
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> VST:
"""Return VectorStore initialized from texts and embeddings."""
raise NotImplementedError
[docs] def as_retriever(self, **kwargs: Any) -> BaseRetriever:
return VectorStoreRetriever(vectorstore=self, **kwargs)
class VectorStoreRetriever(BaseRetriever, BaseModel):
vectorstore: VectorStore
search_type: str = "similarity"
search_kwargs: dict = Field(default_factory=dict)
class Config:
"""Configuration for this pydantic object."""
arbitrary_types_allowed = True
@root_validator()
def validate_search_type(cls, values: Dict) -> Dict:
"""Validate search type."""
if "search_type" in values:
search_type = values["search_type"]
if search_type not in ("similarity", "mmr"):
raise ValueError(f"search_type of {search_type} not allowed.")
return values
def get_relevant_documents(self, query: str) -> List[Document]:
if self.search_type == "similarity":
docs = self.vectorstore.similarity_search(query, **self.search_kwargs)
elif self.search_type == "mmr":
docs = self.vectorstore.max_marginal_relevance_search(
query, **self.search_kwargs
)
else:
raise ValueError(f"search_type of {self.search_type} not allowed.")
return docs
async def aget_relevant_documents(self, query: str) -> List[Document]:
if self.search_type == "similarity":
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if self.search_type == "similarity":
docs = await self.vectorstore.asimilarity_search(
query, **self.search_kwargs
)
elif self.search_type == "mmr":
docs = await self.vectorstore.amax_marginal_relevance_search(
query, **self.search_kwargs
)
else:
raise ValueError(f"search_type of {self.search_type} not allowed.")
return docs
def add_documents(self, documents: List[Document], **kwargs: Any) -> List[str]:
"""Add documents to vectorstore."""
return self.vectorstore.add_documents(documents, **kwargs)
async def aadd_documents(
self, documents: List[Document], **kwargs: Any
) -> List[str]:
"""Add documents to vectorstore."""
return await self.vectorstore.aadd_documents(documents, **kwargs)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
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Source code for langchain.vectorstores.elastic_vector_search
"""Wrapper around Elasticsearch vector database."""
from __future__ import annotations
import uuid
from abc import ABC
from typing import Any, Dict, Iterable, List, Optional, Tuple
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
def _default_text_mapping(dim: int) -> Dict:
return {
"properties": {
"text": {"type": "text"},
"vector": {"type": "dense_vector", "dims": dim},
}
}
def _default_script_query(query_vector: List[float], filter: Optional[dict]) -> Dict:
if filter:
((key, value),) = filter.items()
filter = {"match": {f"metadata.{key}.keyword": f"{value}"}}
else:
filter = {"match_all": {}}
return {
"script_score": {
"query": filter,
"script": {
"source": "cosineSimilarity(params.query_vector, 'vector') + 1.0",
"params": {"query_vector": query_vector},
},
}
}
# ElasticVectorSearch is a concrete implementation of the abstract base class
# VectorStore, which defines a common interface for all vector database
# implementations. By inheriting from the ABC class, ElasticVectorSearch can be
# defined as an abstract base class itself, allowing the creation of subclasses with
# their own specific implementations. If you plan to subclass ElasticVectorSearch,
# you can inherit from it and define your own implementation of the necessary methods
# and attributes.
[docs]class ElasticVectorSearch(VectorStore, ABC):
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# and attributes.
[docs]class ElasticVectorSearch(VectorStore, ABC):
"""Wrapper around Elasticsearch as a vector database.
To connect to an Elasticsearch instance that does not require
login credentials, pass the Elasticsearch URL and index name along with the
embedding object to the constructor.
Example:
.. code-block:: python
from langchain import ElasticVectorSearch
from langchain.embeddings import OpenAIEmbeddings
embedding = OpenAIEmbeddings()
elastic_vector_search = ElasticVectorSearch(
elasticsearch_url="http://localhost:9200",
index_name="test_index",
embedding=embedding
)
To connect to an Elasticsearch instance that requires login credentials,
including Elastic Cloud, use the Elasticsearch URL format
https://username:password@es_host:9243. For example, to connect to Elastic
Cloud, create the Elasticsearch URL with the required authentication details and
pass it to the ElasticVectorSearch constructor as the named parameter
elasticsearch_url.
You can obtain your Elastic Cloud URL and login credentials by logging in to the
Elastic Cloud console at https://cloud.elastic.co, selecting your deployment, and
navigating to the "Deployments" page.
To obtain your Elastic Cloud password for the default "elastic" user:
1. Log in to the Elastic Cloud console at https://cloud.elastic.co
2. Go to "Security" > "Users"
3. Locate the "elastic" user and click "Edit"
4. Click "Reset password"
5. Follow the prompts to reset the password
The format for Elastic Cloud URLs is
https://username:password@cluster_id.region_id.gcp.cloud.es.io:9243.
Example:
.. code-block:: python
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Example:
.. code-block:: python
from langchain import ElasticVectorSearch
from langchain.embeddings import OpenAIEmbeddings
embedding = OpenAIEmbeddings()
elastic_host = "cluster_id.region_id.gcp.cloud.es.io"
elasticsearch_url = f"https://username:password@{elastic_host}:9243"
elastic_vector_search = ElasticVectorSearch(
elasticsearch_url=elasticsearch_url,
index_name="test_index",
embedding=embedding
)
Args:
elasticsearch_url (str): The URL for the Elasticsearch instance.
index_name (str): The name of the Elasticsearch index for the embeddings.
embedding (Embeddings): An object that provides the ability to embed text.
It should be an instance of a class that subclasses the Embeddings
abstract base class, such as OpenAIEmbeddings()
Raises:
ValueError: If the elasticsearch python package is not installed.
"""
def __init__(self, elasticsearch_url: str, index_name: str, embedding: Embeddings):
"""Initialize with necessary components."""
try:
import elasticsearch
except ImportError:
raise ValueError(
"Could not import elasticsearch python package. "
"Please install it with `pip install elasticsearch`."
)
self.embedding = embedding
self.index_name = index_name
try:
es_client = elasticsearch.Elasticsearch(elasticsearch_url) # noqa
except ValueError as e:
raise ValueError(
f"Your elasticsearch client string is misformatted. Got error: {e} "
)
self.client = es_client
[docs] def add_texts(
self,
texts: Iterable[str],
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[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
refresh_indices: bool = True,
**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.
refresh_indices: bool to refresh ElasticSearch indices
Returns:
List of ids from adding the texts into the vectorstore.
"""
try:
from elasticsearch.exceptions import NotFoundError
from elasticsearch.helpers import bulk
except ImportError:
raise ValueError(
"Could not import elasticsearch python package. "
"Please install it with `pip install elasticsearch`."
)
requests = []
ids = []
embeddings = self.embedding.embed_documents(list(texts))
dim = len(embeddings[0])
mapping = _default_text_mapping(dim)
# check to see if the index already exists
try:
self.client.indices.get(index=self.index_name)
except NotFoundError:
# TODO would be nice to create index before embedding,
# just to save expensive steps for last
self.client.indices.create(index=self.index_name, mappings=mapping)
for i, text in enumerate(texts):
metadata = metadatas[i] if metadatas else {}
_id = str(uuid.uuid4())
request = {
"_op_type": "index",
"_index": self.index_name,
"vector": embeddings[i],
"text": text,
"metadata": metadata,
"_id": _id,
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"metadata": metadata,
"_id": _id,
}
ids.append(_id)
requests.append(request)
bulk(self.client, requests)
if refresh_indices:
self.client.indices.refresh(index=self.index_name)
return ids
[docs] def similarity_search(
self, query: str, k: int = 4, filter: Optional[dict] = None, **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.
"""
docs_and_scores = self.similarity_search_with_score(query, k, filter=filter)
documents = [d[0] for d in docs_and_scores]
return documents
[docs] def similarity_search_with_score(
self, query: str, k: int = 4, filter: Optional[dict] = None, **kwargs: Any
) -> 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.
"""
embedding = self.embedding.embed_query(query)
script_query = _default_script_query(embedding, filter)
response = self.client.search(index=self.index_name, query=script_query, size=k)
hits = [hit for hit in response["hits"]["hits"]]
docs_and_scores = [
(
Document(
page_content=hit["_source"]["text"],
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(
Document(
page_content=hit["_source"]["text"],
metadata=hit["_source"]["metadata"],
),
hit["_score"],
)
for hit in hits
]
return docs_and_scores
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> ElasticVectorSearch:
"""Construct ElasticVectorSearch wrapper from raw documents.
This is a user-friendly interface that:
1. Embeds documents.
2. Creates a new index for the embeddings in the Elasticsearch instance.
3. Adds the documents to the newly created Elasticsearch index.
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import ElasticVectorSearch
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
elastic_vector_search = ElasticVectorSearch.from_texts(
texts,
embeddings,
elasticsearch_url="http://localhost:9200"
)
"""
elasticsearch_url = get_from_dict_or_env(
kwargs, "elasticsearch_url", "ELASTICSEARCH_URL"
)
try:
import elasticsearch
from elasticsearch.exceptions import NotFoundError
from elasticsearch.helpers import bulk
except ImportError:
raise ValueError(
"Could not import elasticsearch python package. "
"Please install it with `pip install elasticsearch`."
)
try:
client = elasticsearch.Elasticsearch(elasticsearch_url)
except ValueError as e:
raise ValueError(
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except ValueError as e:
raise ValueError(
"Your elasticsearch client string is misformatted. " f"Got error: {e} "
)
index_name = kwargs.get("index_name", uuid.uuid4().hex)
embeddings = embedding.embed_documents(texts)
dim = len(embeddings[0])
mapping = _default_text_mapping(dim)
# check to see if the index already exists
try:
client.indices.get(index=index_name)
except NotFoundError:
# TODO would be nice to create index before embedding,
# just to save expensive steps for last
client.indices.create(index=index_name, mappings=mapping)
requests = []
for i, text in enumerate(texts):
metadata = metadatas[i] if metadatas else {}
request = {
"_op_type": "index",
"_index": index_name,
"vector": embeddings[i],
"text": text,
"metadata": metadata,
}
requests.append(request)
bulk(client, requests)
client.indices.refresh(index=index_name)
return cls(elasticsearch_url, index_name, embedding)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
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Source code for langchain.vectorstores.deeplake
"""Wrapper around Activeloop Deep Lake."""
from __future__ import annotations
import logging
import uuid
from functools import partial
from typing import Any, Callable, Dict, Iterable, List, Optional, Sequence, Tuple
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__)
distance_metric_map = {
"l2": lambda a, b: np.linalg.norm(a - b, axis=1, ord=2),
"l1": lambda a, b: np.linalg.norm(a - b, axis=1, ord=1),
"max": lambda a, b: np.linalg.norm(a - b, axis=1, ord=np.inf),
"cos": lambda a, b: np.dot(a, b.T)
/ (np.linalg.norm(a) * np.linalg.norm(b, axis=1)),
"dot": lambda a, b: np.dot(a, b.T),
}
def vector_search(
query_embedding: np.ndarray,
data_vectors: np.ndarray,
distance_metric: str = "L2",
k: Optional[int] = 4,
) -> Tuple[List, List]:
"""Naive search for nearest neighbors
args:
query_embedding: np.ndarray
data_vectors: np.ndarray
k (int): number of nearest neighbors
distance_metric: distance function 'L2' for Euclidean, 'L1' for Nuclear, 'Max'
l-infinity distnace, 'cos' for cosine similarity, 'dot' for dot product
returns:
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returns:
nearest_indices: List, indices of nearest neighbors
"""
if data_vectors.shape[0] == 0:
return [], []
# Calculate the distance between the query_vector and all data_vectors
distances = distance_metric_map[distance_metric](query_embedding, data_vectors)
nearest_indices = np.argsort(distances)
nearest_indices = (
nearest_indices[::-1][:k] if distance_metric in ["cos"] else nearest_indices[:k]
)
return nearest_indices.tolist(), distances[nearest_indices].tolist()
def dp_filter(x: dict, filter: Dict[str, str]) -> bool:
"""Filter helper function for Deep Lake"""
metadata = x["metadata"].data()["value"]
return all(k in metadata and v == metadata[k] for k, v in filter.items())
[docs]class DeepLake(VectorStore):
"""Wrapper around Deep Lake, a data lake for deep learning applications.
We implement naive similarity search and filtering for fast prototyping,
but it can be extended with Tensor Query Language (TQL) for production use cases
over billion rows.
Why Deep Lake?
- Not only stores embeddings, but also the original data with version control.
- Serverless, doesn't require another service and can be used with major
cloud providers (S3, GCS, etc.)
- More than just a multi-modal vector store. You can use the dataset
to fine-tune your own LLM models.
To use, you should have the ``deeplake`` python package installed.
Example:
.. code-block:: python
from langchain.vectorstores import DeepLake
from langchain.embeddings.openai import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
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embeddings = OpenAIEmbeddings()
vectorstore = DeepLake("langchain_store", embeddings.embed_query)
"""
_LANGCHAIN_DEFAULT_DEEPLAKE_PATH = "./deeplake/"
def __init__(
self,
dataset_path: str = _LANGCHAIN_DEFAULT_DEEPLAKE_PATH,
token: Optional[str] = None,
embedding_function: Optional[Embeddings] = None,
read_only: Optional[bool] = False,
ingestion_batch_size: int = 1024,
num_workers: int = 0,
**kwargs: Any,
) -> None:
"""Initialize with Deep Lake client."""
self.ingestion_batch_size = ingestion_batch_size
self.num_workers = num_workers
try:
import deeplake
from deeplake.constants import MB
except ImportError:
raise ValueError(
"Could not import deeplake python package. "
"Please install it with `pip install deeplake`."
)
self._deeplake = deeplake
self.dataset_path = dataset_path
creds_args = {"creds": kwargs["creds"]} if "creds" in kwargs else {}
if (
deeplake.exists(dataset_path, token=token, **creds_args)
and "overwrite" not in kwargs
):
self.ds = deeplake.load(
dataset_path, token=token, read_only=read_only, **kwargs
)
logger.warning(
f"Deep Lake Dataset in {dataset_path} already exists, "
f"loading from the storage"
)
self.ds.summary()
else:
if "overwrite" in kwargs:
del kwargs["overwrite"]
self.ds = deeplake.empty(
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del kwargs["overwrite"]
self.ds = deeplake.empty(
dataset_path, token=token, overwrite=True, **kwargs
)
with self.ds:
self.ds.create_tensor(
"text",
htype="text",
create_id_tensor=False,
create_sample_info_tensor=False,
create_shape_tensor=False,
chunk_compression="lz4",
)
self.ds.create_tensor(
"metadata",
htype="json",
create_id_tensor=False,
create_sample_info_tensor=False,
create_shape_tensor=False,
chunk_compression="lz4",
)
self.ds.create_tensor(
"embedding",
htype="generic",
dtype=np.float32,
create_id_tensor=False,
create_sample_info_tensor=False,
max_chunk_size=64 * MB,
create_shape_tensor=True,
)
self.ds.create_tensor(
"ids",
htype="text",
create_id_tensor=False,
create_sample_info_tensor=False,
create_shape_tensor=False,
chunk_compression="lz4",
)
self._embedding_function = embedding_function
[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.
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ids (Optional[List[str]], optional): Optional list of IDs.
Returns:
List[str]: List of IDs of the added texts.
"""
if ids is None:
ids = [str(uuid.uuid1()) for _ in texts]
text_list = list(texts)
if metadatas is None:
metadatas = [{}] * len(text_list)
elements = list(zip(text_list, metadatas, ids))
@self._deeplake.compute
def ingest(sample_in: list, sample_out: list) -> None:
text_list = [s[0] for s in sample_in]
embeds: Sequence[Optional[np.ndarray]] = []
if self._embedding_function is not None:
embeddings = self._embedding_function.embed_documents(text_list)
embeds = [np.array(e, dtype=np.float32) for e in embeddings]
else:
embeds = [None] * len(text_list)
for s, e in zip(sample_in, embeds):
sample_out.append(
{
"text": s[0],
"metadata": s[1],
"ids": s[2],
"embedding": e,
}
)
batch_size = min(self.ingestion_batch_size, len(elements))
if batch_size == 0:
return []
batched = [
elements[i : i + batch_size] for i in range(0, len(elements), batch_size)
]
ingest().eval(
batched,
self.ds,
num_workers=min(self.num_workers, len(batched) // max(self.num_workers, 1)),
**kwargs,
)
self.ds.commit(allow_empty=True)
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**kwargs,
)
self.ds.commit(allow_empty=True)
self.ds.summary()
return ids
[docs] def search(
self,
query: Any[str, None] = None,
embedding: Any[float, None] = None,
k: int = 4,
distance_metric: str = "L2",
use_maximal_marginal_relevance: Optional[bool] = False,
fetch_k: Optional[int] = 20,
filter: Optional[Any[Dict[str, str], Callable, str]] = None,
return_score: Optional[bool] = False,
**kwargs: Any,
) -> Any[List[Document], List[Tuple[Document, float]]]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
embedding: Embedding function to use. Defaults to None.
k: Number of Documents to return. Defaults to 4.
distance_metric: `L2` for Euclidean, `L1` for Nuclear,
`max` L-infinity distance, `cos` for cosine similarity,
'dot' for dot product. Defaults to `L2`.
filter: Attribute filter by metadata example {'key': 'value'}. It can also
take [Deep Lake filter]
(https://docs.deeplake.ai/en/latest/deeplake.core.dataset.html#deeplake.core.dataset.Dataset.filter)
Defaults to None.
maximal_marginal_relevance: Whether to use maximal marginal relevance.
Defaults to False.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
Defaults to 20.
return_score: Whether to return the score. Defaults to False.
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return_score: Whether to return the score. Defaults to False.
Returns:
List of Documents selected by the specified distance metric,
if return_score True, return a tuple of (Document, score)
"""
view = self.ds
# attribute based filtering
if filter is not None:
if isinstance(filter, dict):
filter = partial(dp_filter, filter=filter)
view = view.filter(filter)
if len(view) == 0:
return []
if self._embedding_function is None:
view = view.filter(lambda x: query in x["text"].data()["value"])
scores = [1.0] * len(view)
if use_maximal_marginal_relevance:
raise ValueError(
"For MMR search, you must specify an embedding function on"
"creation."
)
else:
emb = embedding or self._embedding_function.embed_query(
query
) # type: ignore
query_emb = np.array(emb, dtype=np.float32)
embeddings = view.embedding.numpy(fetch_chunks=True)
k_search = fetch_k if use_maximal_marginal_relevance else k
indices, scores = vector_search(
query_emb,
embeddings,
k=k_search,
distance_metric=distance_metric.lower(),
)
view = view[indices]
if use_maximal_marginal_relevance:
lambda_mult = kwargs.get("lambda_mult", 0.5)
indices = maximal_marginal_relevance(
query_emb,
embeddings[indices],
k=min(k, len(indices)),
lambda_mult=lambda_mult,
)
view = view[indices]
scores = [scores[i] for i in indices]
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view = view[indices]
scores = [scores[i] for i in indices]
docs = [
Document(
page_content=el["text"].data()["value"],
metadata=el["metadata"].data()["value"],
)
for el in view
]
if return_score:
return [(doc, score) for doc, score in zip(docs, scores)]
return docs
[docs] def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query.
Args:
query: text to embed and run the query on.
k: Number of Documents to return.
Defaults to 4.
query: Text to look up documents similar to.
embedding: Embedding function to use.
Defaults to None.
k: Number of Documents to return.
Defaults to 4.
distance_metric: `L2` for Euclidean, `L1` for Nuclear, `max`
L-infinity distance, `cos` for cosine similarity, 'dot' for dot product
Defaults to `L2`.
filter: Attribute filter by metadata example {'key': 'value'}.
Defaults to None.
maximal_marginal_relevance: Whether to use maximal marginal relevance.
Defaults to False.
fetch_k: Number of Documents to fetch to pass to MMR algorithm.
Defaults to 20.
return_score: Whether to return the score. Defaults to False.
Returns:
List of Documents most similar to the query vector.
"""
return self.search(query=query, k=k, **kwargs)
[docs] def similarity_search_by_vector(
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[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 query vector.
"""
return self.search(embedding=embedding, k=k, **kwargs)
[docs] def similarity_search_with_score(
self,
query: str,
distance_metric: str = "L2",
k: int = 4,
filter: Optional[Dict[str, str]] = None,
) -> List[Tuple[Document, float]]:
"""Run similarity search with Deep Lake with distance returned.
Args:
query (str): Query text to search for.
distance_metric: `L2` for Euclidean, `L1` for Nuclear, `max` L-infinity
distance, `cos` for cosine similarity, 'dot' for dot product.
Defaults to `L2`.
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.
"""
return self.search(
query=query,
k=k,
filter=filter,
return_score=True,
distance_metric=distance_metric,
)
[docs] def max_marginal_relevance_search_by_vector(
self,
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[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.
"""
return self.search(
embedding=embedding,
k=k,
fetch_k=fetch_k,
use_maximal_marginal_relevance=True,
lambda_mult=lambda_mult,
)
[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.
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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.
"""
if self._embedding_function is None:
raise ValueError(
"For MMR search, you must specify an embedding function on" "creation."
)
return self.search(
query=query,
k=k,
fetch_k=fetch_k,
use_maximal_marginal_relevance=True,
lambda_mult=lambda_mult,
)
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Optional[Embeddings] = None,
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
dataset_path: str = _LANGCHAIN_DEFAULT_DEEPLAKE_PATH,
**kwargs: Any,
) -> DeepLake:
"""Create a Deep Lake dataset from a raw documents.
If a dataset_path is specified, the dataset will be persisted in that location,
otherwise by default at `./deeplake`
Args:
path (str, pathlib.Path): - The full path to the dataset. Can be:
- Deep Lake cloud path of the form ``hub://username/dataset_name``.
To write to Deep Lake cloud datasets,
ensure that you are logged in to Deep Lake
(use 'activeloop login' from command line)
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(use 'activeloop login' from command line)
- AWS S3 path of the form ``s3://bucketname/path/to/dataset``.
Credentials are required in either the environment
- Google Cloud Storage path of the form
``gcs://bucketname/path/to/dataset``Credentials are required
in either the environment
- Local file system path of the form ``./path/to/dataset`` or
``~/path/to/dataset`` or ``path/to/dataset``.
- In-memory path of the form ``mem://path/to/dataset`` which doesn't
save the dataset, but keeps it in memory instead.
Should be used only for testing as it does not persist.
documents (List[Document]): List of documents to add.
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.
Returns:
DeepLake: Deep Lake dataset.
"""
deeplake_dataset = cls(
dataset_path=dataset_path, embedding_function=embedding, **kwargs
)
deeplake_dataset.add_texts(texts=texts, metadatas=metadatas, ids=ids)
return deeplake_dataset
[docs] def delete(
self,
ids: Any[List[str], None] = None,
filter: Any[Dict[str, str], None] = None,
delete_all: Any[bool, None] = None,
) -> bool:
"""Delete the entities in the dataset
Args:
ids (Optional[List[str]], optional): The document_ids to delete.
Defaults to None.
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Defaults to None.
filter (Optional[Dict[str, str]], optional): The filter to delete by.
Defaults to None.
delete_all (Optional[bool], optional): Whether to drop the dataset.
Defaults to None.
"""
if delete_all:
self.ds.delete(large_ok=True)
return True
view = None
if ids:
view = self.ds.filter(lambda x: x["ids"].data()["value"] in ids)
ids = list(view.sample_indices)
if filter:
if view is None:
view = self.ds
view = view.filter(partial(dp_filter, filter=filter))
ids = list(view.sample_indices)
with self.ds:
for id in sorted(ids)[::-1]:
self.ds.pop(id)
self.ds.commit(f"deleted {len(ids)} samples", allow_empty=True)
return True
[docs] @classmethod
def force_delete_by_path(cls, path: str) -> None:
"""Force delete dataset by path"""
try:
import deeplake
except ImportError:
raise ValueError(
"Could not import deeplake python package. "
"Please install it with `pip install deeplake`."
)
deeplake.delete(path, large_ok=True, force=True)
[docs] def delete_dataset(self) -> None:
"""Delete the collection."""
self.delete(delete_all=True)
[docs] def persist(self) -> None:
"""Persist the collection."""
self.ds.flush()
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/vectorstores/deeplake.html
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186f637cab59-0
|
Source code for langchain.memory.buffer
from typing import Any, Dict, List, Optional
from pydantic import root_validator
from langchain.memory.chat_memory import BaseChatMemory, BaseMemory
from langchain.memory.utils import get_prompt_input_key
from langchain.schema import get_buffer_string
[docs]class ConversationBufferMemory(BaseChatMemory):
"""Buffer for storing conversation memory."""
human_prefix: str = "Human"
ai_prefix: str = "AI"
memory_key: str = "history" #: :meta private:
@property
def buffer(self) -> Any:
"""String buffer of memory."""
if self.return_messages:
return self.chat_memory.messages
else:
return get_buffer_string(
self.chat_memory.messages,
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, Any]:
"""Return history buffer."""
return {self.memory_key: self.buffer}
[docs]class ConversationStringBufferMemory(BaseMemory):
"""Buffer for storing conversation memory."""
human_prefix: str = "Human"
ai_prefix: str = "AI"
"""Prefix to use for AI generated responses."""
buffer: str = ""
output_key: Optional[str] = None
input_key: Optional[str] = None
memory_key: str = "history" #: :meta private:
@root_validator()
def validate_chains(cls, values: Dict) -> Dict:
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@root_validator()
def validate_chains(cls, values: Dict) -> Dict:
"""Validate that return messages is not True."""
if values.get("return_messages", False):
raise ValueError(
"return_messages must be False for ConversationStringBufferMemory"
)
return values
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, str]:
"""Return history buffer."""
return {self.memory_key: self.buffer}
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer."""
if self.input_key is None:
prompt_input_key = get_prompt_input_key(inputs, self.memory_variables)
else:
prompt_input_key = self.input_key
if self.output_key is None:
if len(outputs) != 1:
raise ValueError(f"One output key expected, got {outputs.keys()}")
output_key = list(outputs.keys())[0]
else:
output_key = self.output_key
human = f"{self.human_prefix}: " + inputs[prompt_input_key]
ai = f"{self.ai_prefix}: " + outputs[output_key]
self.buffer += "\n" + "\n".join([human, ai])
[docs] def clear(self) -> None:
"""Clear memory contents."""
self.buffer = ""
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/buffer.html
|
1fbc8d2efe36-0
|
Source code for langchain.memory.token_buffer
from typing import Any, Dict, List
from langchain.memory.chat_memory import BaseChatMemory
from langchain.schema import BaseLanguageModel, BaseMessage, get_buffer_string
[docs]class ConversationTokenBufferMemory(BaseChatMemory):
"""Buffer for storing conversation memory."""
human_prefix: str = "Human"
ai_prefix: str = "AI"
llm: BaseLanguageModel
memory_key: str = "history"
max_token_limit: int = 2000
@property
def buffer(self) -> List[BaseMessage]:
"""String buffer of memory."""
return self.chat_memory.messages
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, Any]:
"""Return history buffer."""
buffer: Any = self.buffer
if self.return_messages:
final_buffer: Any = buffer
else:
final_buffer = get_buffer_string(
buffer,
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
return {self.memory_key: final_buffer}
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer. Pruned."""
super().save_context(inputs, outputs)
# Prune buffer if it exceeds max token limit
buffer = self.chat_memory.messages
curr_buffer_length = self.llm.get_num_tokens_from_messages(buffer)
if curr_buffer_length > self.max_token_limit:
pruned_memory = []
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if curr_buffer_length > self.max_token_limit:
pruned_memory = []
while curr_buffer_length > self.max_token_limit:
pruned_memory.append(buffer.pop(0))
curr_buffer_length = self.llm.get_num_tokens_from_messages(buffer)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/token_buffer.html
|
58ce1a3fba5d-0
|
Source code for langchain.memory.readonly
from typing import Any, Dict, List
from langchain.schema import BaseMemory
[docs]class ReadOnlySharedMemory(BaseMemory):
"""A memory wrapper that is read-only and cannot be changed."""
memory: BaseMemory
@property
def memory_variables(self) -> List[str]:
"""Return memory variables."""
return self.memory.memory_variables
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, str]:
"""Load memory variables from memory."""
return self.memory.load_memory_variables(inputs)
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Nothing should be saved or changed"""
pass
[docs] def clear(self) -> None:
"""Nothing to clear, got a memory like a vault."""
pass
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/readonly.html
|
ecb6b16e0b8d-0
|
Source code for langchain.memory.combined
from typing import Any, Dict, List
from langchain.schema import BaseMemory
[docs]class CombinedMemory(BaseMemory):
"""Class for combining multiple memories' data together."""
memories: List[BaseMemory]
"""For tracking all the memories that should be accessed."""
@property
def memory_variables(self) -> List[str]:
"""All the memory variables that this instance provides."""
"""Collected from the all the linked memories."""
memory_variables = []
for memory in self.memories:
memory_variables.extend(memory.memory_variables)
return memory_variables
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, str]:
"""Load all vars from sub-memories."""
memory_data: Dict[str, Any] = {}
# Collect vars from all sub-memories
for memory in self.memories:
data = memory.load_memory_variables(inputs)
memory_data = {
**memory_data,
**data,
}
return memory_data
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this session for every memory."""
# Save context for all sub-memories
for memory in self.memories:
memory.save_context(inputs, outputs)
[docs] def clear(self) -> None:
"""Clear context from this session for every memory."""
for memory in self.memories:
memory.clear()
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/combined.html
|
61b9687795b1-0
|
Source code for langchain.memory.buffer_window
from typing import Any, Dict, List
from langchain.memory.chat_memory import BaseChatMemory
from langchain.schema import BaseMessage, get_buffer_string
[docs]class ConversationBufferWindowMemory(BaseChatMemory):
"""Buffer for storing conversation memory."""
human_prefix: str = "Human"
ai_prefix: str = "AI"
memory_key: str = "history" #: :meta private:
k: int = 5
@property
def buffer(self) -> List[BaseMessage]:
"""String buffer of memory."""
return self.chat_memory.messages
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, str]:
"""Return history buffer."""
buffer: Any = self.buffer[-self.k * 2 :] if self.k > 0 else []
if not self.return_messages:
buffer = get_buffer_string(
buffer,
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
return {self.memory_key: buffer}
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/buffer_window.html
|
916d1ee07c37-0
|
Source code for langchain.memory.simple
from typing import Any, Dict, List
from langchain.schema import BaseMemory
[docs]class SimpleMemory(BaseMemory):
"""Simple memory for storing context or other bits of information that shouldn't
ever change between prompts.
"""
memories: Dict[str, Any] = dict()
@property
def memory_variables(self) -> List[str]:
return list(self.memories.keys())
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, str]:
return self.memories
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Nothing should be saved or changed, my memory is set in stone."""
pass
[docs] def clear(self) -> None:
"""Nothing to clear, got a memory like a vault."""
pass
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/simple.html
|
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|
Source code for langchain.memory.entity
import logging
from abc import ABC, abstractmethod
from itertools import islice
from typing import Any, Dict, Iterable, List, Optional
from pydantic import Field
from langchain.chains.llm import LLMChain
from langchain.memory.chat_memory import BaseChatMemory
from langchain.memory.prompt import (
ENTITY_EXTRACTION_PROMPT,
ENTITY_SUMMARIZATION_PROMPT,
)
from langchain.memory.utils import get_prompt_input_key
from langchain.prompts.base import BasePromptTemplate
from langchain.schema import BaseLanguageModel, BaseMessage, get_buffer_string
logger = logging.getLogger(__name__)
class BaseEntityStore(ABC):
@abstractmethod
def get(self, key: str, default: Optional[str] = None) -> Optional[str]:
"""Get entity value from store."""
pass
@abstractmethod
def set(self, key: str, value: Optional[str]) -> None:
"""Set entity value in store."""
pass
@abstractmethod
def delete(self, key: str) -> None:
"""Delete entity value from store."""
pass
@abstractmethod
def exists(self, key: str) -> bool:
"""Check if entity exists in store."""
pass
@abstractmethod
def clear(self) -> None:
"""Delete all entities from store."""
pass
[docs]class InMemoryEntityStore(BaseEntityStore):
"""Basic in-memory entity store."""
store: Dict[str, Optional[str]] = {}
[docs] def get(self, key: str, default: Optional[str] = None) -> Optional[str]:
return self.store.get(key, default)
[docs] def set(self, key: str, value: Optional[str]) -> None:
|
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|
[docs] def set(self, key: str, value: Optional[str]) -> None:
self.store[key] = value
[docs] def delete(self, key: str) -> None:
del self.store[key]
[docs] def exists(self, key: str) -> bool:
return key in self.store
[docs] def clear(self) -> None:
return self.store.clear()
[docs]class RedisEntityStore(BaseEntityStore):
"""Redis-backed Entity store. Entities get a TTL of 1 day by default, and
that TTL is extended by 3 days every time the entity is read back.
"""
redis_client: Any
session_id: str = "default"
key_prefix: str = "memory_store"
ttl: Optional[int] = 60 * 60 * 24
recall_ttl: Optional[int] = 60 * 60 * 24 * 3
def __init__(
self,
session_id: str = "default",
url: str = "redis://localhost:6379/0",
key_prefix: str = "memory_store",
ttl: Optional[int] = 60 * 60 * 24,
recall_ttl: Optional[int] = 60 * 60 * 24 * 3,
*args: Any,
**kwargs: Any,
):
try:
import redis
except ImportError:
raise ValueError(
"Could not import redis python package. "
"Please install it with `pip install redis`."
)
super().__init__(*args, **kwargs)
try:
self.redis_client = redis.Redis.from_url(url=url, decode_responses=True)
except redis.exceptions.ConnectionError as error:
|
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|
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|
except redis.exceptions.ConnectionError as error:
logger.error(error)
self.session_id = session_id
self.key_prefix = key_prefix
self.ttl = ttl
self.recall_ttl = recall_ttl or ttl
@property
def full_key_prefix(self) -> str:
return f"{self.key_prefix}:{self.session_id}"
[docs] def get(self, key: str, default: Optional[str] = None) -> Optional[str]:
res = (
self.redis_client.getex(f"{self.full_key_prefix}:{key}", ex=self.recall_ttl)
or default
or ""
)
logger.debug(f"REDIS MEM get '{self.full_key_prefix}:{key}': '{res}'")
return res
[docs] def set(self, key: str, value: Optional[str]) -> None:
if not value:
return self.delete(key)
self.redis_client.set(f"{self.full_key_prefix}:{key}", value, ex=self.ttl)
logger.debug(
f"REDIS MEM set '{self.full_key_prefix}:{key}': '{value}' EX {self.ttl}"
)
[docs] def delete(self, key: str) -> None:
self.redis_client.delete(f"{self.full_key_prefix}:{key}")
[docs] def exists(self, key: str) -> bool:
return self.redis_client.exists(f"{self.full_key_prefix}:{key}") == 1
[docs] def clear(self) -> None:
# iterate a list in batches of size batch_size
def batched(iterable: Iterable[Any], batch_size: int) -> Iterable[Any]:
iterator = iter(iterable)
while batch := list(islice(iterator, batch_size)):
yield batch
for keybatch in batched(
|
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|
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|
yield batch
for keybatch in batched(
self.redis_client.scan_iter(f"{self.full_key_prefix}:*"), 500
):
self.redis_client.delete(*keybatch)
[docs]class ConversationEntityMemory(BaseChatMemory):
"""Entity extractor & summarizer to memory."""
human_prefix: str = "Human"
ai_prefix: str = "AI"
llm: BaseLanguageModel
entity_extraction_prompt: BasePromptTemplate = ENTITY_EXTRACTION_PROMPT
entity_summarization_prompt: BasePromptTemplate = ENTITY_SUMMARIZATION_PROMPT
entity_cache: List[str] = []
k: int = 3
chat_history_key: str = "history"
entity_store: BaseEntityStore = Field(default_factory=InMemoryEntityStore)
@property
def buffer(self) -> List[BaseMessage]:
return self.chat_memory.messages
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return ["entities", self.chat_history_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, Any]:
"""Return history buffer."""
chain = LLMChain(llm=self.llm, prompt=self.entity_extraction_prompt)
if self.input_key is None:
prompt_input_key = get_prompt_input_key(inputs, self.memory_variables)
else:
prompt_input_key = self.input_key
buffer_string = get_buffer_string(
self.buffer[-self.k * 2 :],
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
output = chain.predict(
history=buffer_string,
input=inputs[prompt_input_key],
)
|
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|
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|
history=buffer_string,
input=inputs[prompt_input_key],
)
if output.strip() == "NONE":
entities = []
else:
entities = [w.strip() for w in output.split(",")]
entity_summaries = {}
for entity in entities:
entity_summaries[entity] = self.entity_store.get(entity, "")
self.entity_cache = entities
if self.return_messages:
buffer: Any = self.buffer[-self.k * 2 :]
else:
buffer = buffer_string
return {
self.chat_history_key: buffer,
"entities": entity_summaries,
}
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer."""
super().save_context(inputs, outputs)
if self.input_key is None:
prompt_input_key = get_prompt_input_key(inputs, self.memory_variables)
else:
prompt_input_key = self.input_key
buffer_string = get_buffer_string(
self.buffer[-self.k * 2 :],
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
input_data = inputs[prompt_input_key]
chain = LLMChain(llm=self.llm, prompt=self.entity_summarization_prompt)
for entity in self.entity_cache:
existing_summary = self.entity_store.get(entity, "")
output = chain.predict(
summary=existing_summary,
entity=entity,
history=buffer_string,
input=input_data,
)
self.entity_store.set(entity, output.strip())
[docs] def clear(self) -> None:
"""Clear memory contents."""
self.chat_memory.clear()
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"""Clear memory contents."""
self.chat_memory.clear()
self.entity_store.clear()
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/entity.html
|
d94026ab92e3-0
|
Source code for langchain.memory.summary_buffer
from typing import Any, Dict, List
from pydantic import root_validator
from langchain.memory.chat_memory import BaseChatMemory
from langchain.memory.summary import SummarizerMixin
from langchain.schema import BaseMessage, get_buffer_string
[docs]class ConversationSummaryBufferMemory(BaseChatMemory, SummarizerMixin):
"""Buffer with summarizer for storing conversation memory."""
max_token_limit: int = 2000
moving_summary_buffer: str = ""
memory_key: str = "history"
@property
def buffer(self) -> List[BaseMessage]:
return self.chat_memory.messages
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, Any]:
"""Return history buffer."""
buffer = self.buffer
if self.moving_summary_buffer != "":
first_messages: List[BaseMessage] = [
self.summary_message_cls(content=self.moving_summary_buffer)
]
buffer = first_messages + buffer
if self.return_messages:
final_buffer: Any = buffer
else:
final_buffer = get_buffer_string(
buffer, human_prefix=self.human_prefix, ai_prefix=self.ai_prefix
)
return {self.memory_key: final_buffer}
@root_validator()
def validate_prompt_input_variables(cls, values: Dict) -> Dict:
"""Validate that prompt input variables are consistent."""
prompt_variables = values["prompt"].input_variables
expected_keys = {"summary", "new_lines"}
if expected_keys != set(prompt_variables):
raise ValueError(
|
https://python.langchain.com/en/latest/_modules/langchain/memory/summary_buffer.html
|
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|
if expected_keys != set(prompt_variables):
raise ValueError(
"Got unexpected prompt input variables. The prompt expects "
f"{prompt_variables}, but it should have {expected_keys}."
)
return values
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer."""
super().save_context(inputs, outputs)
# Prune buffer if it exceeds max token limit
buffer = self.chat_memory.messages
curr_buffer_length = self.llm.get_num_tokens_from_messages(buffer)
if curr_buffer_length > self.max_token_limit:
pruned_memory = []
while curr_buffer_length > self.max_token_limit:
pruned_memory.append(buffer.pop(0))
curr_buffer_length = self.llm.get_num_tokens_from_messages(buffer)
self.moving_summary_buffer = self.predict_new_summary(
pruned_memory, self.moving_summary_buffer
)
[docs] def clear(self) -> None:
"""Clear memory contents."""
super().clear()
self.moving_summary_buffer = ""
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/summary_buffer.html
|
1be30a28a8d5-0
|
Source code for langchain.memory.kg
from typing import Any, Dict, List, Type, Union
from pydantic import Field
from langchain.chains.llm import LLMChain
from langchain.graphs import NetworkxEntityGraph
from langchain.graphs.networkx_graph import KnowledgeTriple, get_entities, parse_triples
from langchain.memory.chat_memory import BaseChatMemory
from langchain.memory.prompt import (
ENTITY_EXTRACTION_PROMPT,
KNOWLEDGE_TRIPLE_EXTRACTION_PROMPT,
)
from langchain.memory.utils import get_prompt_input_key
from langchain.prompts.base import BasePromptTemplate
from langchain.schema import (
BaseLanguageModel,
BaseMessage,
SystemMessage,
get_buffer_string,
)
[docs]class ConversationKGMemory(BaseChatMemory):
"""Knowledge graph memory for storing conversation memory.
Integrates with external knowledge graph to store and retrieve
information about knowledge triples in the conversation.
"""
k: int = 2
human_prefix: str = "Human"
ai_prefix: str = "AI"
kg: NetworkxEntityGraph = Field(default_factory=NetworkxEntityGraph)
knowledge_extraction_prompt: BasePromptTemplate = KNOWLEDGE_TRIPLE_EXTRACTION_PROMPT
entity_extraction_prompt: BasePromptTemplate = ENTITY_EXTRACTION_PROMPT
llm: BaseLanguageModel
summary_message_cls: Type[BaseMessage] = SystemMessage
"""Number of previous utterances to include in the context."""
memory_key: str = "history" #: :meta private:
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, Any]:
"""Return history buffer."""
entities = self._get_current_entities(inputs)
summary_strings = []
for entity in entities:
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|
summary_strings = []
for entity in entities:
knowledge = self.kg.get_entity_knowledge(entity)
if knowledge:
summary = f"On {entity}: {'. '.join(knowledge)}."
summary_strings.append(summary)
context: Union[str, List]
if not summary_strings:
context = [] if self.return_messages else ""
elif self.return_messages:
context = [
self.summary_message_cls(content=text) for text in summary_strings
]
else:
context = "\n".join(summary_strings)
return {self.memory_key: context}
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
def _get_prompt_input_key(self, inputs: Dict[str, Any]) -> str:
"""Get the input key for the prompt."""
if self.input_key is None:
return get_prompt_input_key(inputs, self.memory_variables)
return self.input_key
def _get_prompt_output_key(self, outputs: Dict[str, Any]) -> str:
"""Get the output key for the prompt."""
if self.output_key is None:
if len(outputs) != 1:
raise ValueError(f"One output key expected, got {outputs.keys()}")
return list(outputs.keys())[0]
return self.output_key
[docs] def get_current_entities(self, input_string: str) -> List[str]:
chain = LLMChain(llm=self.llm, prompt=self.entity_extraction_prompt)
buffer_string = get_buffer_string(
self.chat_memory.messages[-self.k * 2 :],
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
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|
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
output = chain.predict(
history=buffer_string,
input=input_string,
)
return get_entities(output)
def _get_current_entities(self, inputs: Dict[str, Any]) -> List[str]:
"""Get the current entities in the conversation."""
prompt_input_key = self._get_prompt_input_key(inputs)
return self.get_current_entities(inputs[prompt_input_key])
[docs] def get_knowledge_triplets(self, input_string: str) -> List[KnowledgeTriple]:
chain = LLMChain(llm=self.llm, prompt=self.knowledge_extraction_prompt)
buffer_string = get_buffer_string(
self.chat_memory.messages[-self.k * 2 :],
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
output = chain.predict(
history=buffer_string,
input=input_string,
verbose=True,
)
knowledge = parse_triples(output)
return knowledge
def _get_and_update_kg(self, inputs: Dict[str, Any]) -> None:
"""Get and update knowledge graph from the conversation history."""
prompt_input_key = self._get_prompt_input_key(inputs)
knowledge = self.get_knowledge_triplets(inputs[prompt_input_key])
for triple in knowledge:
self.kg.add_triple(triple)
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer."""
super().save_context(inputs, outputs)
self._get_and_update_kg(inputs)
[docs] def clear(self) -> None:
"""Clear memory contents."""
super().clear()
|
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|
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|
"""Clear memory contents."""
super().clear()
self.kg.clear()
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/kg.html
|
cb541ea77e95-0
|
Source code for langchain.memory.summary
from typing import Any, Dict, List, Type
from pydantic import BaseModel, root_validator
from langchain.chains.llm import LLMChain
from langchain.memory.chat_memory import BaseChatMemory
from langchain.memory.prompt import SUMMARY_PROMPT
from langchain.prompts.base import BasePromptTemplate
from langchain.schema import (
BaseLanguageModel,
BaseMessage,
SystemMessage,
get_buffer_string,
)
class SummarizerMixin(BaseModel):
human_prefix: str = "Human"
ai_prefix: str = "AI"
llm: BaseLanguageModel
prompt: BasePromptTemplate = SUMMARY_PROMPT
summary_message_cls: Type[BaseMessage] = SystemMessage
def predict_new_summary(
self, messages: List[BaseMessage], existing_summary: str
) -> str:
new_lines = get_buffer_string(
messages,
human_prefix=self.human_prefix,
ai_prefix=self.ai_prefix,
)
chain = LLMChain(llm=self.llm, prompt=self.prompt)
return chain.predict(summary=existing_summary, new_lines=new_lines)
[docs]class ConversationSummaryMemory(BaseChatMemory, SummarizerMixin):
"""Conversation summarizer to memory."""
buffer: str = ""
memory_key: str = "history" #: :meta private:
@property
def memory_variables(self) -> List[str]:
"""Will always return list of memory variables.
:meta private:
"""
return [self.memory_key]
[docs] def load_memory_variables(self, inputs: Dict[str, Any]) -> Dict[str, Any]:
"""Return history buffer."""
if self.return_messages:
|
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|
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|
"""Return history buffer."""
if self.return_messages:
buffer: Any = [self.summary_message_cls(content=self.buffer)]
else:
buffer = self.buffer
return {self.memory_key: buffer}
@root_validator()
def validate_prompt_input_variables(cls, values: Dict) -> Dict:
"""Validate that prompt input variables are consistent."""
prompt_variables = values["prompt"].input_variables
expected_keys = {"summary", "new_lines"}
if expected_keys != set(prompt_variables):
raise ValueError(
"Got unexpected prompt input variables. The prompt expects "
f"{prompt_variables}, but it should have {expected_keys}."
)
return values
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer."""
super().save_context(inputs, outputs)
self.buffer = self.predict_new_summary(
self.chat_memory.messages[-2:], self.buffer
)
[docs] def clear(self) -> None:
"""Clear memory contents."""
super().clear()
self.buffer = ""
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/summary.html
|
6ef83f9c1431-0
|
Source code for langchain.memory.vectorstore
"""Class for a VectorStore-backed memory object."""
from typing import Any, Dict, List, Optional, Union
from pydantic import Field
from langchain.memory.chat_memory import BaseMemory
from langchain.memory.utils import get_prompt_input_key
from langchain.schema import Document
from langchain.vectorstores.base import VectorStoreRetriever
[docs]class VectorStoreRetrieverMemory(BaseMemory):
"""Class for a VectorStore-backed memory object."""
retriever: VectorStoreRetriever = Field(exclude=True)
"""VectorStoreRetriever object to connect to."""
memory_key: str = "history" #: :meta private:
"""Key name to locate the memories in the result of load_memory_variables."""
input_key: Optional[str] = None
"""Key name to index the inputs to load_memory_variables."""
return_docs: bool = False
"""Whether or not to return the result of querying the database directly."""
@property
def memory_variables(self) -> List[str]:
"""The list of keys emitted from the load_memory_variables method."""
return [self.memory_key]
def _get_prompt_input_key(self, inputs: Dict[str, Any]) -> str:
"""Get the input key for the prompt."""
if self.input_key is None:
return get_prompt_input_key(inputs, self.memory_variables)
return self.input_key
[docs] def load_memory_variables(
self, inputs: Dict[str, Any]
) -> Dict[str, Union[List[Document], str]]:
"""Return history buffer."""
input_key = self._get_prompt_input_key(inputs)
query = inputs[input_key]
docs = self.retriever.get_relevant_documents(query)
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|
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|
docs = self.retriever.get_relevant_documents(query)
result: Union[List[Document], str]
if not self.return_docs:
result = "\n".join([doc.page_content for doc in docs])
else:
result = docs
return {self.memory_key: result}
def _form_documents(
self, inputs: Dict[str, Any], outputs: Dict[str, str]
) -> List[Document]:
"""Format context from this conversation to buffer."""
# Each document should only include the current turn, not the chat history
filtered_inputs = {k: v for k, v in inputs.items() if k != self.memory_key}
texts = [
f"{k}: {v}"
for k, v in list(filtered_inputs.items()) + list(outputs.items())
]
page_content = "\n".join(texts)
return [Document(page_content=page_content)]
[docs] def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
"""Save context from this conversation to buffer."""
documents = self._form_documents(inputs, outputs)
self.retriever.add_documents(documents)
[docs] def clear(self) -> None:
"""Nothing to clear."""
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/vectorstore.html
|
c3d65e25aae1-0
|
Source code for langchain.memory.chat_message_histories.in_memory
from typing import List
from pydantic import BaseModel
from langchain.schema import (
AIMessage,
BaseChatMessageHistory,
BaseMessage,
HumanMessage,
)
[docs]class ChatMessageHistory(BaseChatMessageHistory, BaseModel):
messages: List[BaseMessage] = []
[docs] def add_user_message(self, message: str) -> None:
self.messages.append(HumanMessage(content=message))
[docs] def add_ai_message(self, message: str) -> None:
self.messages.append(AIMessage(content=message))
[docs] def clear(self) -> None:
self.messages = []
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/in_memory.html
|
2d5e29de3350-0
|
Source code for langchain.memory.chat_message_histories.cosmos_db
"""Azure CosmosDB Memory History."""
from __future__ import annotations
import logging
from types import TracebackType
from typing import TYPE_CHECKING, Any, List, Optional, Type
from langchain.schema import (
AIMessage,
BaseChatMessageHistory,
BaseMessage,
HumanMessage,
messages_from_dict,
messages_to_dict,
)
logger = logging.getLogger(__name__)
if TYPE_CHECKING:
from azure.cosmos import ContainerProxy, CosmosClient
[docs]class CosmosDBChatMessageHistory(BaseChatMessageHistory):
"""Chat history backed by Azure CosmosDB."""
def __init__(
self,
cosmos_endpoint: str,
cosmos_database: str,
cosmos_container: str,
credential: Any,
session_id: str,
user_id: str,
ttl: Optional[int] = None,
):
"""
Initializes a new instance of the CosmosDBChatMessageHistory class.
:param cosmos_endpoint: The connection endpoint for the Azure Cosmos DB account.
:param cosmos_database: The name of the database to use.
:param cosmos_container: The name of the container to use.
:param credential: The credential to use to authenticate to Azure Cosmos DB.
:param session_id: The session ID to use, can be overwritten while loading.
:param user_id: The user ID to use, can be overwritten while loading.
:param ttl: The time to live (in seconds) to use for documents in the container.
"""
self.cosmos_endpoint = cosmos_endpoint
self.cosmos_database = cosmos_database
self.cosmos_container = cosmos_container
self.credential = credential
self.session_id = session_id
|
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|
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|
self.credential = credential
self.session_id = session_id
self.user_id = user_id
self.ttl = ttl
self._client: Optional[CosmosClient] = None
self._container: Optional[ContainerProxy] = None
self.messages: List[BaseMessage] = []
[docs] def prepare_cosmos(self) -> None:
"""Prepare the CosmosDB client.
Use this function or the context manager to make sure your database is ready.
"""
try:
from azure.cosmos import ( # pylint: disable=import-outside-toplevel # noqa: E501
CosmosClient,
PartitionKey,
)
except ImportError as exc:
raise ImportError(
"You must install the azure-cosmos package to use the CosmosDBChatMessageHistory." # noqa: E501
) from exc
self._client = CosmosClient(
url=self.cosmos_endpoint, credential=self.credential
)
database = self._client.create_database_if_not_exists(self.cosmos_database)
self._container = database.create_container_if_not_exists(
self.cosmos_container,
partition_key=PartitionKey("/user_id"),
default_ttl=self.ttl,
)
self.load_messages()
def __enter__(self) -> "CosmosDBChatMessageHistory":
"""Context manager entry point."""
if self._client:
self._client.__enter__()
self.prepare_cosmos()
return self
raise ValueError("Client not initialized")
def __exit__(
self,
exc_type: Optional[Type[BaseException]],
exc_val: Optional[BaseException],
traceback: Optional[TracebackType],
) -> None:
"""Context manager exit"""
|
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|
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|
) -> None:
"""Context manager exit"""
self.upsert_messages()
if self._client:
self._client.__exit__(exc_type, exc_val, traceback)
[docs] def load_messages(self) -> None:
"""Retrieve the messages from Cosmos"""
if not self._container:
raise ValueError("Container not initialized")
try:
from azure.cosmos.exceptions import ( # pylint: disable=import-outside-toplevel # noqa: E501
CosmosHttpResponseError,
)
except ImportError as exc:
raise ImportError(
"You must install the azure-cosmos package to use the CosmosDBChatMessageHistory." # noqa: E501
) from exc
try:
item = self._container.read_item(
item=self.session_id, partition_key=self.user_id
)
except CosmosHttpResponseError:
logger.info("no session found")
return
if (
"messages" in item
and len(item["messages"]) > 0
and isinstance(item["messages"][0], list)
):
self.messages = messages_from_dict(item["messages"])
[docs] def add_user_message(self, message: str) -> None:
"""Add a user message to the memory."""
self.upsert_messages(HumanMessage(content=message))
[docs] def add_ai_message(self, message: str) -> None:
"""Add a AI message to the memory."""
self.upsert_messages(AIMessage(content=message))
[docs] def upsert_messages(self, new_message: Optional[BaseMessage] = None) -> None:
"""Update the cosmosdb item."""
if new_message:
self.messages.append(new_message)
if not self._container:
|
https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/cosmos_db.html
|
2d5e29de3350-3
|
self.messages.append(new_message)
if not self._container:
raise ValueError("Container not initialized")
self._container.upsert_item(
body={
"id": self.session_id,
"user_id": self.user_id,
"messages": messages_to_dict(self.messages),
}
)
[docs] def clear(self) -> None:
"""Clear session memory from this memory and cosmos."""
self.messages = []
if self._container:
self._container.delete_item(
item=self.session_id, partition_key=self.user_id
)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/cosmos_db.html
|
5c9d5978bd68-0
|
Source code for langchain.memory.chat_message_histories.postgres
import json
import logging
from typing import List
from langchain.schema import (
AIMessage,
BaseChatMessageHistory,
BaseMessage,
HumanMessage,
_message_to_dict,
messages_from_dict,
)
logger = logging.getLogger(__name__)
DEFAULT_CONNECTION_STRING = "postgresql://postgres:mypassword@localhost/chat_history"
[docs]class PostgresChatMessageHistory(BaseChatMessageHistory):
def __init__(
self,
session_id: str,
connection_string: str = DEFAULT_CONNECTION_STRING,
table_name: str = "message_store",
):
import psycopg
from psycopg.rows import dict_row
try:
self.connection = psycopg.connect(connection_string)
self.cursor = self.connection.cursor(row_factory=dict_row)
except psycopg.OperationalError as error:
logger.error(error)
self.session_id = session_id
self.table_name = table_name
self._create_table_if_not_exists()
def _create_table_if_not_exists(self) -> None:
create_table_query = f"""CREATE TABLE IF NOT EXISTS {self.table_name} (
id SERIAL PRIMARY KEY,
session_id TEXT NOT NULL,
message JSONB NOT NULL
);"""
self.cursor.execute(create_table_query)
self.connection.commit()
@property
def messages(self) -> List[BaseMessage]: # type: ignore
"""Retrieve the messages from PostgreSQL"""
query = f"SELECT message FROM {self.table_name} WHERE session_id = %s;"
self.cursor.execute(query, (self.session_id,))
items = [record["message"] for record in self.cursor.fetchall()]
messages = messages_from_dict(items)
return messages
|
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|
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|
messages = messages_from_dict(items)
return messages
[docs] def add_user_message(self, message: str) -> None:
self.append(HumanMessage(content=message))
[docs] def add_ai_message(self, message: str) -> None:
self.append(AIMessage(content=message))
[docs] def append(self, message: BaseMessage) -> None:
"""Append the message to the record in PostgreSQL"""
from psycopg import sql
query = sql.SQL("INSERT INTO {} (session_id, message) VALUES (%s, %s);").format(
sql.Identifier(self.table_name)
)
self.cursor.execute(
query, (self.session_id, json.dumps(_message_to_dict(message)))
)
self.connection.commit()
[docs] def clear(self) -> None:
"""Clear session memory from PostgreSQL"""
query = f"DELETE FROM {self.table_name} WHERE session_id = %s;"
self.cursor.execute(query, (self.session_id,))
self.connection.commit()
def __del__(self) -> None:
if self.cursor:
self.cursor.close()
if self.connection:
self.connection.close()
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/postgres.html
|
4f3c2d50f665-0
|
Source code for langchain.memory.chat_message_histories.redis
import json
import logging
from typing import List, Optional
from langchain.schema import (
AIMessage,
BaseChatMessageHistory,
BaseMessage,
HumanMessage,
_message_to_dict,
messages_from_dict,
)
logger = logging.getLogger(__name__)
[docs]class RedisChatMessageHistory(BaseChatMessageHistory):
def __init__(
self,
session_id: str,
url: str = "redis://localhost:6379/0",
key_prefix: str = "message_store:",
ttl: Optional[int] = None,
):
try:
import redis
except ImportError:
raise ValueError(
"Could not import redis python package. "
"Please install it with `pip install redis`."
)
try:
self.redis_client = redis.Redis.from_url(url=url)
except redis.exceptions.ConnectionError as error:
logger.error(error)
self.session_id = session_id
self.key_prefix = key_prefix
self.ttl = ttl
@property
def key(self) -> str:
"""Construct the record key to use"""
return self.key_prefix + self.session_id
@property
def messages(self) -> List[BaseMessage]: # type: ignore
"""Retrieve the messages from Redis"""
_items = self.redis_client.lrange(self.key, 0, -1)
items = [json.loads(m.decode("utf-8")) for m in _items[::-1]]
messages = messages_from_dict(items)
return messages
[docs] def add_user_message(self, message: str) -> None:
self.append(HumanMessage(content=message))
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https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/redis.html
|
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self.append(HumanMessage(content=message))
[docs] def add_ai_message(self, message: str) -> None:
self.append(AIMessage(content=message))
[docs] def append(self, message: BaseMessage) -> None:
"""Append the message to the record in Redis"""
self.redis_client.lpush(self.key, json.dumps(_message_to_dict(message)))
if self.ttl:
self.redis_client.expire(self.key, self.ttl)
[docs] def clear(self) -> None:
"""Clear session memory from Redis"""
self.redis_client.delete(self.key)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/redis.html
|
e2ce08602ba0-0
|
Source code for langchain.memory.chat_message_histories.dynamodb
import logging
from typing import List
from langchain.schema import (
AIMessage,
BaseChatMessageHistory,
BaseMessage,
HumanMessage,
_message_to_dict,
messages_from_dict,
messages_to_dict,
)
logger = logging.getLogger(__name__)
[docs]class DynamoDBChatMessageHistory(BaseChatMessageHistory):
"""Chat message history that stores history in AWS DynamoDB.
This class expects that a DynamoDB table with name `table_name`
and a partition Key of `SessionId` is present.
Args:
table_name: name of the DynamoDB table
session_id: arbitrary key that is used to store the messages
of a single chat session.
"""
def __init__(self, table_name: str, session_id: str):
import boto3
client = boto3.resource("dynamodb")
self.table = client.Table(table_name)
self.session_id = session_id
@property
def messages(self) -> List[BaseMessage]: # type: ignore
"""Retrieve the messages from DynamoDB"""
from botocore.exceptions import ClientError
try:
response = self.table.get_item(Key={"SessionId": self.session_id})
except ClientError as error:
if error.response["Error"]["Code"] == "ResourceNotFoundException":
logger.warning("No record found with session id: %s", self.session_id)
else:
logger.error(error)
if response and "Item" in response:
items = response["Item"]["History"]
else:
items = []
messages = messages_from_dict(items)
return messages
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https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/dynamodb.html
|
e2ce08602ba0-1
|
items = []
messages = messages_from_dict(items)
return messages
[docs] def add_user_message(self, message: str) -> None:
self.append(HumanMessage(content=message))
[docs] def add_ai_message(self, message: str) -> None:
self.append(AIMessage(content=message))
[docs] def append(self, message: BaseMessage) -> None:
"""Append the message to the record in DynamoDB"""
from botocore.exceptions import ClientError
messages = messages_to_dict(self.messages)
_message = _message_to_dict(message)
messages.append(_message)
try:
self.table.put_item(
Item={"SessionId": self.session_id, "History": messages}
)
except ClientError as err:
logger.error(err)
[docs] def clear(self) -> None:
"""Clear session memory from DynamoDB"""
from botocore.exceptions import ClientError
try:
self.table.delete_item(Key={"SessionId": self.session_id})
except ClientError as err:
logger.error(err)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/memory/chat_message_histories/dynamodb.html
|
e50443a7435a-0
|
Source code for langchain.retrievers.remote_retriever
from typing import List, Optional
import aiohttp
import requests
from pydantic import BaseModel
from langchain.schema import BaseRetriever, Document
[docs]class RemoteLangChainRetriever(BaseRetriever, BaseModel):
url: str
headers: Optional[dict] = None
input_key: str = "message"
response_key: str = "response"
page_content_key: str = "page_content"
metadata_key: str = "metadata"
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
response = requests.post(
self.url, json={self.input_key: query}, headers=self.headers
)
result = response.json()
return [
Document(
page_content=r[self.page_content_key], metadata=r[self.metadata_key]
)
for r in result[self.response_key]
]
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
async with aiohttp.ClientSession() as session:
async with session.request(
"POST", self.url, headers=self.headers, json={self.input_key: query}
) as response:
result = await response.json()
return [
Document(
page_content=r[self.page_content_key], metadata=r[self.metadata_key]
)
for r in result[self.response_key]
]
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/remote_retriever.html
|
eddbf36f259d-0
|
Source code for langchain.retrievers.weaviate_hybrid_search
"""Wrapper around weaviate vector database."""
from __future__ import annotations
from typing import Any, Dict, List, Optional
from uuid import uuid4
from pydantic import Extra
from langchain.docstore.document import Document
from langchain.schema import BaseRetriever
[docs]class WeaviateHybridSearchRetriever(BaseRetriever):
def __init__(
self,
client: Any,
index_name: str,
text_key: str,
alpha: float = 0.5,
k: int = 4,
attributes: Optional[List[str]] = None,
):
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.k = k
self.alpha = alpha
self._index_name = index_name
self._text_key = text_key
self._query_attrs = [self._text_key]
if attributes is not None:
self._query_attrs.extend(attributes)
[docs] class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
# added text_key
[docs] def add_documents(self, docs: List[Document]) -> List[str]:
"""Upload documents to Weaviate."""
from weaviate.util import get_valid_uuid
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/weaviate_hybrid_search.html
|
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|
"""Upload documents to Weaviate."""
from weaviate.util import get_valid_uuid
with self._client.batch as batch:
ids = []
for i, doc in enumerate(docs):
metadata = doc.metadata or {}
data_properties = {self._text_key: doc.page_content, **metadata}
_id = get_valid_uuid(uuid4())
batch.add_data_object(data_properties, self._index_name, _id)
ids.append(_id)
return ids
[docs] def get_relevant_documents(
self, query: str, where_filter: Optional[Dict[str, object]] = None
) -> List[Document]:
"""Look up similar documents in Weaviate."""
query_obj = self._client.query.get(self._index_name, self._query_attrs)
if where_filter:
query_obj = query_obj.with_where(where_filter)
result = query_obj.with_hybrid(query, alpha=self.alpha).with_limit(self.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] async def aget_relevant_documents(
self, query: str, where_filter: Optional[Dict[str, object]] = None
) -> List[Document]:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/weaviate_hybrid_search.html
|
7cbf4e3d031f-0
|
Source code for langchain.retrievers.metal
from typing import Any, List, Optional
from langchain.schema import BaseRetriever, Document
[docs]class MetalRetriever(BaseRetriever):
def __init__(self, client: Any, params: Optional[dict] = None):
from metal_sdk.metal import Metal
if not isinstance(client, Metal):
raise ValueError(
"Got unexpected client, should be of type metal_sdk.metal.Metal. "
f"Instead, got {type(client)}"
)
self.client: Metal = client
self.params = params or {}
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
results = self.client.search({"text": query}, **self.params)
final_results = []
for r in results["data"]:
metadata = {k: v for k, v in r.items() if k != "text"}
final_results.append(Document(page_content=r["text"], metadata=metadata))
return final_results
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/metal.html
|
3e072665204c-0
|
Source code for langchain.retrievers.chatgpt_plugin_retriever
from __future__ import annotations
from typing import List, Optional
import aiohttp
import requests
from pydantic import BaseModel
from langchain.schema import BaseRetriever, Document
[docs]class ChatGPTPluginRetriever(BaseRetriever, BaseModel):
url: str
bearer_token: str
top_k: int = 3
filter: Optional[dict] = None
aiosession: Optional[aiohttp.ClientSession] = None
class Config:
"""Configuration for this pydantic object."""
arbitrary_types_allowed = True
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
url, json, headers = self._create_request(query)
response = requests.post(url, json=json, headers=headers)
results = response.json()["results"][0]["results"]
docs = []
for d in results:
content = d.pop("text")
docs.append(Document(page_content=content, metadata=d))
return docs
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
url, json, headers = self._create_request(query)
if not self.aiosession:
async with aiohttp.ClientSession() as session:
async with session.post(url, headers=headers, json=json) as response:
res = await response.json()
else:
async with self.aiosession.post(
url, headers=headers, json=json
) as response:
res = await response.json()
results = res["results"][0]["results"]
docs = []
for d in results:
content = d.pop("text")
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/chatgpt_plugin_retriever.html
|
3e072665204c-1
|
docs = []
for d in results:
content = d.pop("text")
docs.append(Document(page_content=content, metadata=d))
return docs
def _create_request(self, query: str) -> tuple[str, dict, dict]:
url = f"{self.url}/query"
json = {
"queries": [
{
"query": query,
"filter": self.filter,
"top_k": self.top_k,
}
]
}
headers = {
"Content-Type": "application/json",
"Authorization": f"Bearer {self.bearer_token}",
}
return url, json, headers
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/chatgpt_plugin_retriever.html
|
31a2187b2614-0
|
Source code for langchain.retrievers.svm
"""SMV Retriever.
Largely based on
https://github.com/karpathy/randomfun/blob/master/knn_vs_svm.ipynb"""
from __future__ import annotations
import concurrent.futures
from typing import Any, List, Optional
import numpy as np
from pydantic import BaseModel
from langchain.embeddings.base import Embeddings
from langchain.schema import BaseRetriever, Document
def create_index(contexts: List[str], embeddings: Embeddings) -> np.ndarray:
with concurrent.futures.ThreadPoolExecutor() as executor:
return np.array(list(executor.map(embeddings.embed_query, contexts)))
[docs]class SVMRetriever(BaseRetriever, BaseModel):
embeddings: Embeddings
index: Any
texts: List[str]
k: int = 4
relevancy_threshold: Optional[float] = None
class Config:
"""Configuration for this pydantic object."""
arbitrary_types_allowed = True
[docs] @classmethod
def from_texts(
cls, texts: List[str], embeddings: Embeddings, **kwargs: Any
) -> SVMRetriever:
index = create_index(texts, embeddings)
return cls(embeddings=embeddings, index=index, texts=texts, **kwargs)
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
from sklearn import svm
query_embeds = np.array(self.embeddings.embed_query(query))
x = np.concatenate([query_embeds[None, ...], self.index])
y = np.zeros(x.shape[0])
y[0] = 1
clf = svm.LinearSVC(
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/svm.html
|
31a2187b2614-1
|
y[0] = 1
clf = svm.LinearSVC(
class_weight="balanced", verbose=False, max_iter=10000, tol=1e-6, C=0.1
)
clf.fit(x, y)
similarities = clf.decision_function(x)
sorted_ix = np.argsort(-similarities)
# svm.LinearSVC in scikit-learn is non-deterministic.
# if a text is the same as a query, there is no guarantee
# the query will be in the first index.
# this performs a simple swap, this works because anything
# left of the 0 should be equivalent.
zero_index = np.where(sorted_ix == 0)[0][0]
if zero_index != 0:
sorted_ix[0], sorted_ix[zero_index] = sorted_ix[zero_index], sorted_ix[0]
denominator = np.max(similarities) - np.min(similarities) + 1e-6
normalized_similarities = (similarities - np.min(similarities)) / denominator
top_k_results = []
for row in sorted_ix[1 : self.k + 1]:
if (
self.relevancy_threshold is None
or normalized_similarities[row] >= self.relevancy_threshold
):
top_k_results.append(Document(page_content=self.texts[row - 1]))
return top_k_results
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/svm.html
|
01df99248c0b-0
|
Source code for langchain.retrievers.tfidf
"""TF-IDF Retriever.
Largely based on
https://github.com/asvskartheek/Text-Retrieval/blob/master/TF-IDF%20Search%20Engine%20(SKLEARN).ipynb"""
from typing import Any, Dict, List, Optional
from pydantic import BaseModel
from langchain.schema import BaseRetriever, Document
[docs]class TFIDFRetriever(BaseRetriever, BaseModel):
vectorizer: Any
docs: List[Document]
tfidf_array: Any
k: int = 4
class Config:
"""Configuration for this pydantic object."""
arbitrary_types_allowed = True
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
tfidf_params: Optional[Dict[str, Any]] = None,
**kwargs: Any
) -> "TFIDFRetriever":
from sklearn.feature_extraction.text import TfidfVectorizer
tfidf_params = tfidf_params or {}
vectorizer = TfidfVectorizer(**tfidf_params)
tfidf_array = vectorizer.fit_transform(texts)
docs = [Document(page_content=t) for t in texts]
return cls(vectorizer=vectorizer, docs=docs, tfidf_array=tfidf_array, **kwargs)
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
from sklearn.metrics.pairwise import cosine_similarity
query_vec = self.vectorizer.transform(
[query]
) # Ip -- (n_docs,x), Op -- (n_docs,n_Feats)
results = cosine_similarity(self.tfidf_array, query_vec).reshape(
(-1,)
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/tfidf.html
|
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|
results = cosine_similarity(self.tfidf_array, query_vec).reshape(
(-1,)
) # Op -- (n_docs,1) -- Cosine Sim with each doc
return_docs = []
for i in results.argsort()[-self.k :][::-1]:
return_docs.append(self.docs[i])
return return_docs
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/tfidf.html
|
ec8e600ec048-0
|
Source code for langchain.retrievers.pinecone_hybrid_search
"""Taken from: https://docs.pinecone.io/docs/hybrid-search"""
import hashlib
from typing import Any, Dict, List, Optional
from pydantic import BaseModel, Extra, root_validator
from langchain.embeddings.base import Embeddings
from langchain.schema import BaseRetriever, Document
def hash_text(text: str) -> str:
return str(hashlib.sha256(text.encode("utf-8")).hexdigest())
def create_index(
contexts: List[str],
index: Any,
embeddings: Embeddings,
sparse_encoder: Any,
ids: Optional[List[str]] = None,
) -> None:
batch_size = 32
_iterator = range(0, len(contexts), batch_size)
try:
from tqdm.auto import tqdm
_iterator = tqdm(_iterator)
except ImportError:
pass
if ids is None:
# create unique ids using hash of the text
ids = [hash_text(context) for context in contexts]
for i in _iterator:
# find end of batch
i_end = min(i + batch_size, len(contexts))
# extract batch
context_batch = contexts[i:i_end]
batch_ids = ids[i:i_end]
# add context passages as metadata
meta = [{"context": context} for context in context_batch]
# create dense vectors
dense_embeds = embeddings.embed_documents(context_batch)
# create sparse vectors
sparse_embeds = sparse_encoder.encode_documents(context_batch)
for s in sparse_embeds:
s["values"] = [float(s1) for s1 in s["values"]]
vectors = []
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/pinecone_hybrid_search.html
|
ec8e600ec048-1
|
vectors = []
# loop through the data and create dictionaries for upserts
for doc_id, sparse, dense, metadata in zip(
batch_ids, sparse_embeds, dense_embeds, meta
):
vectors.append(
{
"id": doc_id,
"sparse_values": sparse,
"values": dense,
"metadata": metadata,
}
)
# upload the documents to the new hybrid index
index.upsert(vectors)
[docs]class PineconeHybridSearchRetriever(BaseRetriever, BaseModel):
embeddings: Embeddings
sparse_encoder: Any
index: Any
top_k: int = 4
alpha: float = 0.5
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
[docs] def add_texts(self, texts: List[str], ids: Optional[List[str]] = None) -> None:
create_index(texts, self.index, self.embeddings, self.sparse_encoder, ids=ids)
@root_validator()
def validate_environment(cls, values: Dict) -> Dict:
"""Validate that api key and python package exists in environment."""
try:
from pinecone_text.hybrid import hybrid_convex_scale # noqa:F401
from pinecone_text.sparse.base_sparse_encoder import (
BaseSparseEncoder, # noqa:F401
)
except ImportError:
raise ValueError(
"Could not import pinecone_text python package. "
"Please install it with `pip install pinecone_text`."
)
return values
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/pinecone_hybrid_search.html
|
ec8e600ec048-2
|
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
from pinecone_text.hybrid import hybrid_convex_scale
sparse_vec = self.sparse_encoder.encode_queries(query)
# convert the question into a dense vector
dense_vec = self.embeddings.embed_query(query)
# scale alpha with hybrid_scale
dense_vec, sparse_vec = hybrid_convex_scale(dense_vec, sparse_vec, self.alpha)
sparse_vec["values"] = [float(s1) for s1 in sparse_vec["values"]]
# query pinecone with the query parameters
result = self.index.query(
vector=dense_vec,
sparse_vector=sparse_vec,
top_k=self.top_k,
include_metadata=True,
)
final_result = []
for res in result["matches"]:
final_result.append(Document(page_content=res["metadata"]["context"]))
# return search results as json
return final_result
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/pinecone_hybrid_search.html
|
45debe33d6ae-0
|
Source code for langchain.retrievers.time_weighted_retriever
"""Retriever that combines embedding similarity with recency in retrieving values."""
from copy import deepcopy
from datetime import datetime
from typing import Any, Dict, List, Optional, Tuple
from pydantic import BaseModel, Field
from langchain.schema import BaseRetriever, Document
from langchain.vectorstores.base import VectorStore
def _get_hours_passed(time: datetime, ref_time: datetime) -> float:
"""Get the hours passed between two datetime objects."""
return (time - ref_time).total_seconds() / 3600
[docs]class TimeWeightedVectorStoreRetriever(BaseRetriever, BaseModel):
"""Retriever combining embededing similarity with recency."""
vectorstore: VectorStore
"""The vectorstore to store documents and determine salience."""
search_kwargs: dict = Field(default_factory=lambda: dict(k=100))
"""Keyword arguments to pass to the vectorstore similarity search."""
# TODO: abstract as a queue
memory_stream: List[Document] = Field(default_factory=list)
"""The memory_stream of documents to search through."""
decay_rate: float = Field(default=0.01)
"""The exponential decay factor used as (1.0-decay_rate)**(hrs_passed)."""
k: int = 4
"""The maximum number of documents to retrieve in a given call."""
other_score_keys: List[str] = []
"""Other keys in the metadata to factor into the score, e.g. 'importance'."""
default_salience: Optional[float] = None
"""The salience to assign memories not retrieved from the vector store.
None assigns no salience to documents not fetched from the vector store.
"""
class Config:
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/time_weighted_retriever.html
|
45debe33d6ae-1
|
"""
class Config:
"""Configuration for this pydantic object."""
arbitrary_types_allowed = True
def _get_combined_score(
self,
document: Document,
vector_relevance: Optional[float],
current_time: datetime,
) -> float:
"""Return the combined score for a document."""
hours_passed = _get_hours_passed(
current_time,
document.metadata["last_accessed_at"],
)
score = (1.0 - self.decay_rate) ** hours_passed
for key in self.other_score_keys:
if key in document.metadata:
score += document.metadata[key]
if vector_relevance is not None:
score += vector_relevance
return score
[docs] def get_salient_docs(self, query: str) -> Dict[int, Tuple[Document, float]]:
"""Return documents that are salient to the query."""
docs_and_scores: List[Tuple[Document, float]]
docs_and_scores = self.vectorstore.similarity_search_with_relevance_scores(
query, **self.search_kwargs
)
results = {}
for fetched_doc, relevance in docs_and_scores:
buffer_idx = fetched_doc.metadata["buffer_idx"]
doc = self.memory_stream[buffer_idx]
results[buffer_idx] = (doc, relevance)
return results
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
"""Return documents that are relevant to the query."""
current_time = datetime.now()
docs_and_scores = {
doc.metadata["buffer_idx"]: (doc, self.default_salience)
for doc in self.memory_stream[-self.k :]
}
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/time_weighted_retriever.html
|
45debe33d6ae-2
|
for doc in self.memory_stream[-self.k :]
}
# If a doc is considered salient, update the salience score
docs_and_scores.update(self.get_salient_docs(query))
rescored_docs = [
(doc, self._get_combined_score(doc, relevance, current_time))
for doc, relevance in docs_and_scores.values()
]
rescored_docs.sort(key=lambda x: x[1], reverse=True)
result = []
# Ensure frequently accessed memories aren't forgotten
current_time = datetime.now()
for doc, _ in rescored_docs[: self.k]:
# TODO: Update vector store doc once `update` method is exposed.
buffered_doc = self.memory_stream[doc.metadata["buffer_idx"]]
buffered_doc.metadata["last_accessed_at"] = current_time
result.append(buffered_doc)
return result
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
"""Return documents that are relevant to the query."""
raise NotImplementedError
[docs] def add_documents(self, documents: List[Document], **kwargs: Any) -> List[str]:
"""Add documents to vectorstore."""
current_time = kwargs.get("current_time", datetime.now())
# Avoid mutating input documents
dup_docs = [deepcopy(d) for d in documents]
for i, doc in enumerate(dup_docs):
if "last_accessed_at" not in doc.metadata:
doc.metadata["last_accessed_at"] = current_time
if "created_at" not in doc.metadata:
doc.metadata["created_at"] = current_time
doc.metadata["buffer_idx"] = len(self.memory_stream) + i
self.memory_stream.extend(dup_docs)
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/time_weighted_retriever.html
|
45debe33d6ae-3
|
self.memory_stream.extend(dup_docs)
return self.vectorstore.add_documents(dup_docs, **kwargs)
[docs] async def aadd_documents(
self, documents: List[Document], **kwargs: Any
) -> List[str]:
"""Add documents to vectorstore."""
current_time = kwargs.get("current_time", datetime.now())
# Avoid mutating input documents
dup_docs = [deepcopy(d) for d in documents]
for i, doc in enumerate(dup_docs):
if "last_accessed_at" not in doc.metadata:
doc.metadata["last_accessed_at"] = current_time
if "created_at" not in doc.metadata:
doc.metadata["created_at"] = current_time
doc.metadata["buffer_idx"] = len(self.memory_stream) + i
self.memory_stream.extend(dup_docs)
return await self.vectorstore.aadd_documents(dup_docs, **kwargs)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/time_weighted_retriever.html
|
85128ab5707b-0
|
Source code for langchain.retrievers.contextual_compression
"""Retriever that wraps a base retriever and filters the results."""
from typing import List
from pydantic import BaseModel, Extra
from langchain.retrievers.document_compressors.base import (
BaseDocumentCompressor,
)
from langchain.schema import BaseRetriever, Document
[docs]class ContextualCompressionRetriever(BaseRetriever, BaseModel):
"""Retriever that wraps a base retriever and compresses the results."""
base_compressor: BaseDocumentCompressor
"""Compressor for compressing retrieved documents."""
base_retriever: BaseRetriever
"""Base Retriever to use for getting relevant documents."""
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
"""Get documents relevant for a query.
Args:
query: string to find relevant documents for
Returns:
Sequence of relevant documents
"""
docs = self.base_retriever.get_relevant_documents(query)
compressed_docs = self.base_compressor.compress_documents(docs, query)
return list(compressed_docs)
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
"""Get documents relevant for a query.
Args:
query: string to find relevant documents for
Returns:
List of relevant documents
"""
docs = await self.base_retriever.aget_relevant_documents(query)
compressed_docs = await self.base_compressor.acompress_documents(docs, query)
return list(compressed_docs)
By Harrison Chase
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/contextual_compression.html
|
85128ab5707b-1
|
return list(compressed_docs)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/contextual_compression.html
|
3ee5ec632d2d-0
|
Source code for langchain.retrievers.elastic_search_bm25
"""Wrapper around Elasticsearch vector database."""
from __future__ import annotations
import uuid
from typing import Any, Iterable, List
from langchain.docstore.document import Document
from langchain.schema import BaseRetriever
[docs]class ElasticSearchBM25Retriever(BaseRetriever):
"""Wrapper around Elasticsearch using BM25 as a retrieval method.
To connect to an Elasticsearch instance that requires login credentials,
including Elastic Cloud, use the Elasticsearch URL format
https://username:password@es_host:9243. For example, to connect to Elastic
Cloud, create the Elasticsearch URL with the required authentication details and
pass it to the ElasticVectorSearch constructor as the named parameter
elasticsearch_url.
You can obtain your Elastic Cloud URL and login credentials by logging in to the
Elastic Cloud console at https://cloud.elastic.co, selecting your deployment, and
navigating to the "Deployments" page.
To obtain your Elastic Cloud password for the default "elastic" user:
1. Log in to the Elastic Cloud console at https://cloud.elastic.co
2. Go to "Security" > "Users"
3. Locate the "elastic" user and click "Edit"
4. Click "Reset password"
5. Follow the prompts to reset the password
The format for Elastic Cloud URLs is
https://username:password@cluster_id.region_id.gcp.cloud.es.io:9243.
"""
def __init__(self, client: Any, index_name: str):
self.client = client
self.index_name = index_name
[docs] @classmethod
def create(
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/elastic_search_bm25.html
|
3ee5ec632d2d-1
|
self.index_name = index_name
[docs] @classmethod
def create(
cls, elasticsearch_url: str, index_name: str, k1: float = 2.0, b: float = 0.75
) -> ElasticSearchBM25Retriever:
from elasticsearch import Elasticsearch
# Create an Elasticsearch client instance
es = Elasticsearch(elasticsearch_url)
# Define the index settings and mappings
settings = {
"analysis": {"analyzer": {"default": {"type": "standard"}}},
"similarity": {
"custom_bm25": {
"type": "BM25",
"k1": k1,
"b": b,
}
},
}
mappings = {
"properties": {
"content": {
"type": "text",
"similarity": "custom_bm25", # Use the custom BM25 similarity
}
}
}
# Create the index with the specified settings and mappings
es.indices.create(index=index_name, mappings=mappings, settings=settings)
return cls(es, index_name)
[docs] def add_texts(
self,
texts: Iterable[str],
refresh_indices: bool = True,
) -> List[str]:
"""Run more texts through the embeddings and add to the retriver.
Args:
texts: Iterable of strings to add to the retriever.
refresh_indices: bool to refresh ElasticSearch indices
Returns:
List of ids from adding the texts into the retriever.
"""
try:
from elasticsearch.helpers import bulk
except ImportError:
raise ValueError(
"Could not import elasticsearch python package. "
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/elastic_search_bm25.html
|
3ee5ec632d2d-2
|
raise ValueError(
"Could not import elasticsearch python package. "
"Please install it with `pip install elasticsearch`."
)
requests = []
ids = []
for i, text in enumerate(texts):
_id = str(uuid.uuid4())
request = {
"_op_type": "index",
"_index": self.index_name,
"content": text,
"_id": _id,
}
ids.append(_id)
requests.append(request)
bulk(self.client, requests)
if refresh_indices:
self.client.indices.refresh(index=self.index_name)
return ids
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
query_dict = {"query": {"match": {"content": query}}}
res = self.client.search(index=self.index_name, body=query_dict)
docs = []
for r in res["hits"]["hits"]:
docs.append(Document(page_content=r["_source"]["content"]))
return docs
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/elastic_search_bm25.html
|
7dd6aeca35a3-0
|
Source code for langchain.retrievers.databerry
from typing import List, Optional
import aiohttp
import requests
from langchain.schema import BaseRetriever, Document
[docs]class DataberryRetriever(BaseRetriever):
datastore_url: str
top_k: Optional[int]
api_key: Optional[str]
def __init__(
self,
datastore_url: str,
top_k: Optional[int] = None,
api_key: Optional[str] = None,
):
self.datastore_url = datastore_url
self.api_key = api_key
self.top_k = top_k
[docs] def get_relevant_documents(self, query: str) -> List[Document]:
response = requests.post(
self.datastore_url,
json={
"query": query,
**({"topK": self.top_k} if self.top_k is not None else {}),
},
headers={
"Content-Type": "application/json",
**(
{"Authorization": f"Bearer {self.api_key}"}
if self.api_key is not None
else {}
),
},
)
data = response.json()
return [
Document(
page_content=r["text"],
metadata={"source": r["source"], "score": r["score"]},
)
for r in data["results"]
]
[docs] async def aget_relevant_documents(self, query: str) -> List[Document]:
async with aiohttp.ClientSession() as session:
async with session.request(
"POST",
self.datastore_url,
json={
"query": query,
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/databerry.html
|
7dd6aeca35a3-1
|
self.datastore_url,
json={
"query": query,
**({"topK": self.top_k} if self.top_k is not None else {}),
},
headers={
"Content-Type": "application/json",
**(
{"Authorization": f"Bearer {self.api_key}"}
if self.api_key is not None
else {}
),
},
) as response:
data = await response.json()
return [
Document(
page_content=r["text"],
metadata={"source": r["source"], "score": r["score"]},
)
for r in data["results"]
]
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 25, 2023.
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/databerry.html
|
4fb06da970d2-0
|
Source code for langchain.retrievers.document_compressors.embeddings_filter
"""Document compressor that uses embeddings to drop documents unrelated to the query."""
from typing import Callable, Dict, Optional, Sequence
import numpy as np
from pydantic import root_validator
from langchain.document_transformers import (
_get_embeddings_from_stateful_docs,
get_stateful_documents,
)
from langchain.embeddings.base import Embeddings
from langchain.math_utils import cosine_similarity
from langchain.retrievers.document_compressors.base import (
BaseDocumentCompressor,
)
from langchain.schema import Document
[docs]class EmbeddingsFilter(BaseDocumentCompressor):
embeddings: Embeddings
"""Embeddings to use for embedding document contents and queries."""
similarity_fn: Callable = cosine_similarity
"""Similarity function for comparing documents. Function expected to take as input
two matrices (List[List[float]]) and return a matrix of scores where higher values
indicate greater similarity."""
k: Optional[int] = 20
"""The number of relevant documents to return. Can be set to None, in which case
`similarity_threshold` must be specified. Defaults to 20."""
similarity_threshold: Optional[float]
"""Threshold for determining when two documents are similar enough
to be considered redundant. Defaults to None, must be specified if `k` is set
to None."""
class Config:
"""Configuration for this pydantic object."""
arbitrary_types_allowed = True
@root_validator()
def validate_params(cls, values: Dict) -> Dict:
"""Validate similarity parameters."""
if values["k"] is None and values["similarity_threshold"] is None:
raise ValueError("Must specify one of `k` or `similarity_threshold`.")
return values
|
https://python.langchain.com/en/latest/_modules/langchain/retrievers/document_compressors/embeddings_filter.html
|
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