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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
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|
ac7d4cf5ea34-15
|
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, embedding: List[float], k: int = 4, fetch_k: int = 20
) -> 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.
Returns:
List of Documents selected by maximal marginal relevance.
"""
return self.search(
embedding=embedding,
k=k,
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|
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|
k=k,
fetch_k=fetch_k,
use_maximal_marginal_relevance=True,
)
[docs] def max_marginal_relevance_search(
self, query: str, k: int = 4, fetch_k: int = 20
) -> 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.
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
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|
use_maximal_marginal_relevance=True
)
[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 there.
Otherwise, the data will be ephemeral in-memory.
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)
- AWS S3 path of the form ``s3://bucketname/path/to/dataset``.
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|
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|
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.
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|
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|
(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,
)
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.
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.
"""
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|
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|
Defaults to None.
"""
if delete_all:
self.ds.delete()
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] 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
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|
ac7d4cf5ea34-21
|
Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
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|
d45648f47994-0
|
Source code for langchain.vectorstores.weaviate
"""Wrapper around weaviate vector database."""
from __future__ import annotations
from typing import Any, Dict, Iterable, List, Optional, Type
from uuid import uuid4
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_schema(index_name: str) -> Dict:
return {
"class": index_name,
"properties": [
{
"name": "text",
"dataType": ["text"],
}
],
}
[docs]class Weaviate(VectorStore):
"""Wrapper around Weaviate vector database.
To use, you should have the ``weaviate-client`` python package installed.
Example:
.. code-block:: python
import weaviate
from langchain.vectorstores import Weaviate
client = weaviate.Client(url=os.environ["WEAVIATE_URL"], ...)
weaviate = Weaviate(client, index_name, text_key)
"""
def __init__(
self,
client: Any,
index_name:
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|
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|
client: Any,
index_name: str,
text_key: str,
attributes: Optional[List[str]] = None,
):
"""Initialize with Weaviate client."""
try:
import weaviate
except ImportError:
raise ValueError(
"Could not import weaviate python package. "
"Please install it with `pip install weaviate-client`."
)
if not isinstance(client, weaviate.Client):
raise ValueError(
f"client should be an instance of weaviate.Client, got {type(client)}"
)
self._client = client
self._index_name = index_name
self._text_key = text_key
self._query_attrs = [self._text_key]
if attributes is not None:
self._query_attrs.extend(attributes)
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]]
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|
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|
Iterable[str],
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> List[str]:
"""Upload texts with metadata (properties) to Weaviate."""
from weaviate.util import get_valid_uuid
with self._client.batch as batch:
ids = []
for i, doc in enumerate(texts):
data_properties = {
self._text_key: doc,
}
if metadatas is not None:
for key in metadatas[i].keys():
data_properties[key] = metadatas[i][key]
_id = get_valid_uuid(uuid4())
batch.add_data_object(
data_object=data_properties, class_name=self._index_name, uuid=_id
)
ids.append(_id)
return
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|
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|
ids.append(_id)
return ids
[docs] def similarity_search(
self, query: str, k: int = 4, **kwargs: Any
) -> List[Document]:
"""Return docs most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
Returns:
List of Documents most similar to the query.
"""
content: Dict[str, Any] = {"concepts": [query]}
if kwargs.get("search_distance"):
content["certainty"] = kwargs.get("search_distance")
query_obj = self._client.query.get(self._index_name, self._query_attrs)
result = query_obj.with_near_text(content).with_limit(k).do()
if "errors" in result:
raise ValueError(f"Error during query: {result['errors']}")
docs = []
for res in result["data"]["Get"][self._index_name]:
text = res.pop(self._text_key)
docs.append(Document(page_content=text, metadata=res))
return
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|
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|
docs.append(Document(page_content=text, metadata=res))
return docs
[docs] def similarity_search_by_vector(
self, embedding: List[float], k: int = 4, **kwargs: Any
) -> List[Document]:
"""Look up similar documents by embedding vector in Weaviate."""
vector = {"vector": embedding}
query_obj = self._client.query.get(self._index_name, self._query_attrs)
result = query_obj.with_near_vector(vector).with_limit(k).do()
if "errors" in result:
raise ValueError(f"Error during query: {result['errors']}")
docs = []
for res in result["data"]["Get"][self._index_name]:
text = res.pop(self._text_key)
docs.append(Document(page_content=text, metadata=res))
return docs
[docs] @classmethod
def from_texts(
cls: Type[Weaviate],
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
**kwargs: Any,
) -> Weaviate:
"""Construct Weaviate wrapper from raw documents.
This is a user-friendly interface that:
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|
d45648f47994-5
|
raw documents.
This is a user-friendly interface that:
1. Embeds documents.
2. Creates a new index for the embeddings in the Weaviate instance.
3. Adds the documents to the newly created Weaviate index.
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain.vectorstores.weaviate import Weaviate
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
weaviate = Weaviate.from_texts(
texts,
embeddings,
weaviate_url="http://localhost:8080"
)
"""
weaviate_url = get_from_dict_or_env(kwargs, "weaviate_url", "WEAVIATE_URL")
try:
from weaviate import Client
|
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|
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|
from weaviate import Client
from weaviate.util import get_valid_uuid
except ImportError:
raise ValueError(
"Could not import weaviate python package. "
"Please install it with `pip instal weaviate-client`"
)
client = Client(weaviate_url)
index_name = kwargs.get("index_name", f"LangChain_{uuid4().hex}")
embeddings = embedding.embed_documents(texts) if embedding else None
text_key = "text"
schema = _default_schema(index_name)
attributes = list(metadatas[0].keys()) if metadatas else None
# check whether the index already exists
if not client.schema.contains(schema):
client.schema.create_class(schema)
with client.batch as batch:
for i, text in enumerate(texts):
data_properties = {
text_key: text,
}
if metadatas is not
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|
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|
if metadatas is not None:
for key in metadatas[i].keys():
data_properties[key] = metadatas[i][key]
_id = get_valid_uuid(uuid4())
# if an embedding strategy is not provided, we let
# weaviate create the embedding. Note that this will only
# work if weaviate has been installed with a vectorizer module
# like text2vec-contextionary for example
params = {
"uuid": _id,
"data_object": data_properties,
"class_name": index_name,
}
if embeddings is not None:
params["vector"] = (embeddings[i],)
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|
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|
batch.add_data_object(**params)
batch.flush()
return cls(client, index_name, text_key, attributes)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
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|
c8b187b2f221-0
|
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
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]) -> Dict:
return {
"script_score": {
"query": {"match_all": {}},
"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
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|
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|
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):
"""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
|
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|
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|
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
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
)
|
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|
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|
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:
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|
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|
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],
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
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|
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|
"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],
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"vector": embeddings[i],
"text": text,
"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, **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.
"""
embedding = self.embedding.embed_query(query)
script_query = _default_script_query(embedding)
response = self.client.search(index=self.index_name, query=script_query, size=k)
hits = [hit["_source"] for hit in response["hits"]["hits"]]
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hits = [hit["_source"] for hit in response["hits"]["hits"]]
documents = [
Document(page_content=hit["text"], metadata=hit["metadata"]) for hit in hits
]
return documents
[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()
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|
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|
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(
"Your
|
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|
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|
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,
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|
c8b187b2f221-10
|
"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 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/vectorstores/elastic_vector_search.html
|
b1d9b023c5c3-0
|
Source code for langchain.vectorstores.pinecone
"""Wrapper around Pinecone vector database."""
from __future__ import annotations
import uuid
from typing import Any, Callable, Iterable, List, Optional, Tuple
from langchain.docstore.document import Document
from langchain.embeddings.base import Embeddings
from langchain.vectorstores.base import VectorStore
[docs]class Pinecone(VectorStore):
"""Wrapper around Pinecone vector database.
To use, you should have the ``pinecone-client`` python package installed.
Example:
.. code-block:: python
from langchain.vectorstores import Pinecone
from langchain.embeddings.openai import OpenAIEmbeddings
import pinecone
# The environment should be the one specified next to the API key
# in your Pinecone console
pinecone.init(api_key="***", environment="...")
index = pinecone.Index("langchain-demo")
embeddings = OpenAIEmbeddings()
vectorstore = Pinecone(index, embeddings.embed_query, "text")
"""
def __init__(
self,
index: Any,
embedding_function: Callable,
text_key: str,
namespace: Optional[str] = None,
):
|
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|
b1d9b023c5c3-1
|
namespace: Optional[str] = None,
):
"""Initialize with Pinecone client."""
try:
import pinecone
except ImportError:
raise ValueError(
"Could not import pinecone python package. "
"Please install it with `pip install pinecone-client`."
)
if not isinstance(index, pinecone.index.Index):
raise ValueError(
f"client should be an instance of pinecone.index.Index, "
f"got {type(index)}"
)
self._index = index
self._embedding_function = embedding_function
self._text_key = text_key
self._namespace = namespace
[docs] def add_texts(
self,
texts: Iterable[str],
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
namespace: Optional[str] = None,
batch_size: int = 32,
**kwargs: Any,
|
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|
b1d9b023c5c3-2
|
int = 32,
**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.
ids: Optional list of ids to associate with the texts.
namespace: Optional pinecone namespace to add the texts to.
Returns:
List of ids from adding the texts into the vectorstore.
"""
if namespace is None:
namespace = self._namespace
# Embed and create the documents
docs = []
ids = ids or [str(uuid.uuid4()) for _ in texts]
for i, text in enumerate(texts):
embedding = self._embedding_function(text)
metadata = metadatas[i] if metadatas else {}
metadata[self._text_key] = text
docs.append((ids[i], embedding, metadata))
# upsert to Pinecone
self._index.upsert(vectors=docs, namespace=namespace,
|
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|
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|
self._index.upsert(vectors=docs, namespace=namespace, batch_size=batch_size)
return ids
[docs] def similarity_search_with_score(
self,
query: str,
k: int = 4,
filter: Optional[dict] = None,
namespace: Optional[str] = None,
) -> List[Tuple[Document, float]]:
"""Return pinecone documents most similar to query, along with scores.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
filter: Dictionary of argument(s) to filter on metadata
namespace: Namespace to search in. Default will search in '' namespace.
Returns:
List of Documents most similar to the query and score for each
"""
if namespace is None:
namespace = self._namespace
query_obj = self._embedding_function(query)
docs = []
results = self._index.query(
[query_obj],
top_k=k,
|
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|
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|
top_k=k,
include_metadata=True,
namespace=namespace,
filter=filter,
)
for res in results["matches"]:
metadata = res["metadata"]
text = metadata.pop(self._text_key)
docs.append((Document(page_content=text, metadata=metadata), res["score"]))
return docs
[docs] def similarity_search(
self,
query: str,
k: int = 4,
filter: Optional[dict] = None,
namespace: Optional[str] = None,
**kwargs: Any,
) -> List[Document]:
"""Return pinecone documents most similar to query.
Args:
query: Text to look up documents similar to.
k: Number of Documents to return. Defaults to 4.
filter: Dictionary of argument(s) to filter on metadata
namespace: Namespace to search in. Default will search in '' namespace.
Returns:
List of Documents most similar to the query and score for each
|
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|
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|
List of Documents most similar to the query and score for each
"""
if namespace is None:
namespace = self._namespace
query_obj = self._embedding_function(query)
docs = []
results = self._index.query(
[query_obj],
top_k=k,
include_metadata=True,
namespace=namespace,
filter=filter,
)
for res in results["matches"]:
metadata = res["metadata"]
text = metadata.pop(self._text_key)
docs.append(Document(page_content=text, metadata=metadata))
return docs
[docs] @classmethod
def from_texts(
cls,
texts: List[str],
embedding: Embeddings,
metadatas: Optional[List[dict]] = None,
ids: Optional[List[str]] = None,
batch_size: int = 32,
text_key: str = "text",
index_name: Optional[str] = None,
namespace:
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/vectorstores/pinecone.html
|
b1d9b023c5c3-6
|
index_name: Optional[str] = None,
namespace: Optional[str] = None,
**kwargs: Any,
) -> Pinecone:
"""Construct Pinecone wrapper from raw documents.
This is a user friendly interface that:
1. Embeds documents.
2. Adds the documents to a provided Pinecone index
This is intended to be a quick way to get started.
Example:
.. code-block:: python
from langchain import Pinecone
from langchain.embeddings import OpenAIEmbeddings
import pinecone
# The environment should be the one specified next to the API key
# in your Pinecone console
pinecone.init(api_key="***", environment="...")
embeddings = OpenAIEmbeddings()
pinecone = Pinecone.from_texts(
texts,
embeddings,
|
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|
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|
embeddings,
index_name="langchain-demo"
)
"""
try:
import pinecone
except ImportError:
raise ValueError(
"Could not import pinecone python package. "
"Please install it with `pip install pinecone-client`."
)
indexes = pinecone.list_indexes() # checks if provided index exists
if index_name in indexes:
index = pinecone.Index(index_name)
elif len(indexes) == 0:
raise ValueError(
"No active indexes found in your Pinecone project, "
"are you sure you're using the right API key and environment?"
)
else:
raise ValueError(
f"Index '{index_name}' not found in your Pinecone project. "
|
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|
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|
Pinecone project. "
"Did you mean one of the following indexes: {', '.join(indexes)}"
)
for i in range(0, len(texts), batch_size):
# set end position of batch
i_end = min(i + batch_size, len(texts))
# get batch of texts and ids
lines_batch = texts[i:i_end]
# create ids if not provided
if ids:
ids_batch = ids[i:i_end]
else:
ids_batch = [str(uuid.uuid4()) for n in range(i, i_end)]
# create embeddings
embeds = embedding.embed_documents(lines_batch)
# prep metadata and upsert batch
if metadatas:
metadata = metadatas[i:i_end]
else:
metadata = [{} for _ in range(i, i_end)]
for j,
|
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|
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|
range(i, i_end)]
for j, line in enumerate(lines_batch):
metadata[j][text_key] = line
to_upsert = zip(ids_batch, embeds, metadata)
# upsert to Pinecone
index.upsert(vectors=list(to_upsert), namespace=namespace)
return cls(index, embedding.embed_query, text_key, namespace)
[docs] @classmethod
def from_existing_index(
cls,
index_name: str,
embedding: Embeddings,
text_key: str = "text",
namespace: Optional[str] = None,
) -> Pinecone:
"""Load pinecone vectorstore from index name."""
try:
import pinecone
except ImportError:
raise ValueError(
"Could not import pinecone python package. "
"Please install it with `pip install pinecone-client`."
)
return cls(
pinecone.Index(index_name), embedding.embed_query, text_key, namespace
)
By
|
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|
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|
embedding.embed_query, text_key, namespace
)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/vectorstores/pinecone.html
|
956523bb813c-0
|
Source code for langchain.docstore.wikipedia
"""Wrapper around wikipedia API."""
from typing import Union
from langchain.docstore.base import Docstore
from langchain.docstore.document import Document
[docs]class Wikipedia(Docstore):
"""Wrapper around wikipedia API."""
def __init__(self) -> None:
"""Check that wikipedia package is installed."""
try:
import wikipedia # noqa: F401
except ImportError:
raise ValueError(
"Could not import wikipedia python package. "
"Please install it with `pip install wikipedia`."
)
[docs] def search(self, search: str) -> Union[str, Document]:
"""Try to search for wiki page.
If page exists, return the page summary, and a PageWithLookups object.
If page does not exist, return similar entries.
"""
import wikipedia
try:
page_content = wikipedia.page(search).content
url = wikipedia.page(search).url
result: Union[str, Document] = Document(
page_content=page_content, metadata={"page": url}
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/docstore/wikipedia.html
|
956523bb813c-1
|
metadata={"page": url}
)
except wikipedia.PageError:
result = f"Could not find [{search}]. Similar: {wikipedia.search(search)}"
except wikipedia.DisambiguationError:
result = f"Could not find [{search}]. Similar: {wikipedia.search(search)}"
return result
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/docstore/wikipedia.html
|
410d582cd4b7-0
|
Source code for langchain.docstore.in_memory
"""Simple in memory docstore in the form of a dict."""
from typing import Dict, Union
from langchain.docstore.base import AddableMixin, Docstore
from langchain.docstore.document import Document
[docs]class InMemoryDocstore(Docstore, AddableMixin):
"""Simple in memory docstore in the form of a dict."""
def __init__(self, _dict: Dict[str, Document]):
"""Initialize with dict."""
self._dict = _dict
[docs] def add(self, texts: Dict[str, Document]) -> None:
"""Add texts to in memory dictionary."""
overlapping = set(texts).intersection(self._dict)
if overlapping:
raise ValueError(f"Tried to add ids that already exist: {overlapping}")
self._dict = dict(self._dict, **texts)
[docs] def search(self, search: str) -> Union[str, Document]:
"""Search via direct lookup."""
if search not in self._dict:
return f"ID {search} not found."
else:
return self._dict[search]
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/docstore/in_memory.html
|
47ced89fa216-0
|
Source code for langchain.prompts.base
"""BasePrompt schema definition."""
from __future__ import annotations
import json
from abc import ABC, abstractmethod
from pathlib import Path
from typing import Any, Callable, Dict, List, Mapping, Optional, Union
import yaml
from pydantic import BaseModel, Extra, Field, root_validator
from langchain.formatting import formatter
from langchain.schema import BaseMessage, BaseOutputParser, HumanMessage, PromptValue
def jinja2_formatter(template: str, **kwargs: Any) -> str:
"""Format a template using jinja2."""
try:
from jinja2 import Template
except ImportError:
raise ValueError(
"jinja2 not installed, which is needed to use the jinja2_formatter. "
"Please install it with `pip install jinja2`."
)
return Template(template).render(**kwargs)
DEFAULT_FORMATTER_MAPPING: Dict[str, Callable] = {
"f-string": formatter.format,
"jinja2": jinja2_formatter,
}
def check_valid_template(
template: str, template_format: str, input_variables: List[str]
) -> None:
"""Check that template string is valid."""
if template_format not in DEFAULT_FORMATTER_MAPPING:
valid_formats = list(DEFAULT_FORMATTER_MAPPING)
raise ValueError(
f"Invalid template format. Got `{template_format}`;"
f" should be one of {valid_formats}"
)
|
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|
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|
f" should be one of {valid_formats}"
)
dummy_inputs = {input_variable: "foo" for input_variable in input_variables}
try:
formatter_func = DEFAULT_FORMATTER_MAPPING[template_format]
formatter_func(template, **dummy_inputs)
except KeyError as e:
raise ValueError(
"Invalid prompt schema; check for mismatched or missing input parameters. "
+ str(e)
)
class StringPromptValue(PromptValue):
text: str
def to_string(self) -> str:
"""Return prompt as string."""
return self.text
def to_messages(self) -> List[BaseMessage]:
"""Return prompt as messages."""
return [HumanMessage(content=self.text)]
[docs]class BasePromptTemplate(BaseModel, ABC):
"""Base class for all prompt templates, returning a prompt."""
input_variables: List[str]
"""A list of the names of the variables the prompt template expects."""
output_parser: Optional[BaseOutputParser] = None
"""How to parse the output of calling an LLM on this formatted prompt."""
partial_variables: Mapping[str, Union[str, Callable[[], str]]] = Field(
default_factory=dict
)
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
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|
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|
object."""
extra = Extra.forbid
arbitrary_types_allowed = True
[docs] @abstractmethod
def format_prompt(self, **kwargs: Any) -> PromptValue:
"""Create Chat Messages."""
@root_validator()
def validate_variable_names(cls, values: Dict) -> Dict:
"""Validate variable names do not include restricted names."""
if "stop" in values["input_variables"]:
raise ValueError(
"Cannot have an input variable named 'stop', as it is used internally,"
" please rename."
)
if "stop" in values["partial_variables"]:
raise ValueError(
"Cannot have an partial variable named 'stop', as it is used "
"internally, please rename."
)
overall = set(values["input_variables"]).intersection(
values["partial_variables"]
)
if overall:
raise ValueError(
f"Found overlapping input and partial variables: {overall}"
)
|
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|
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|
partial variables: {overall}"
)
return values
[docs] def partial(self, **kwargs: Union[str, Callable[[], str]]) -> BasePromptTemplate:
"""Return a partial of the prompt template."""
prompt_dict = self.__dict__.copy()
prompt_dict["input_variables"] = list(
set(self.input_variables).difference(kwargs)
)
prompt_dict["partial_variables"] = {**self.partial_variables, **kwargs}
return type(self)(**prompt_dict)
def _merge_partial_and_user_variables(self, **kwargs: Any) -> Dict[str, Any]:
# Get partial params:
partial_kwargs = {
k: v if isinstance(v, str) else v()
for k, v in self.partial_variables.items()
}
return {**partial_kwargs, **kwargs}
[docs] @abstractmethod
def format(self, **kwargs: Any) -> str:
"""Format the prompt with the inputs.
Args:
kwargs: Any arguments to be passed to the prompt template.
Returns:
A formatted string.
Example:
.. code-block:: python
|
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|
47ced89fa216-4
|
Example:
.. code-block:: python
prompt.format(variable1="foo")
"""
@property
def _prompt_type(self) -> str:
"""Return the prompt type key."""
raise NotImplementedError
[docs] def dict(self, **kwargs: Any) -> Dict:
"""Return dictionary representation of prompt."""
prompt_dict = super().dict(**kwargs)
prompt_dict["_type"] = self._prompt_type
return prompt_dict
[docs] def save(self, file_path: Union[Path, str]) -> None:
"""Save the prompt.
Args:
file_path: Path to directory to save prompt to.
Example:
.. code-block:: python
prompt.save(file_path="path/prompt.yaml")
"""
if self.partial_variables:
raise ValueError("Cannot save prompt with partial variables.")
# Convert file to Path object.
if isinstance(file_path, str):
save_path = Path(file_path)
else:
save_path = file_path
directory_path = save_path.parent
|
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|
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|
= file_path
directory_path = save_path.parent
directory_path.mkdir(parents=True, exist_ok=True)
# Fetch dictionary to save
prompt_dict = self.dict()
if save_path.suffix == ".json":
with open(file_path, "w") as f:
json.dump(prompt_dict, f, indent=4)
elif save_path.suffix == ".yaml":
with open(file_path, "w") as f:
yaml.dump(prompt_dict, f, default_flow_style=False)
else:
raise ValueError(f"{save_path} must be json or yaml")
[docs]class StringPromptTemplate(BasePromptTemplate, ABC):
"""String prompt should expose the format method, returning a prompt."""
[docs] def format_prompt(self, **kwargs: Any) -> PromptValue:
"""Create Chat Messages."""
return StringPromptValue(text=self.format(**kwargs))
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/base.html
|
d056f9d89ff6-0
|
Source code for langchain.prompts.few_shot
"""Prompt template that contains few shot examples."""
from typing import Any, Dict, List, Optional
from pydantic import Extra, root_validator
from langchain.prompts.base import (
DEFAULT_FORMATTER_MAPPING,
StringPromptTemplate,
check_valid_template,
)
from langchain.prompts.example_selector.base import BaseExampleSelector
from langchain.prompts.prompt import PromptTemplate
[docs]class FewShotPromptTemplate(StringPromptTemplate):
"""Prompt template that contains few shot examples."""
examples: Optional[List[dict]] = None
"""Examples to format into the prompt.
Either this or example_selector should be provided."""
example_selector: Optional[BaseExampleSelector] = None
"""ExampleSelector to choose the examples to format into the prompt.
Either this or examples should be provided."""
example_prompt: PromptTemplate
"""PromptTemplate used to format an individual example."""
suffix: str
"""A prompt template string to put after the examples."""
input_variables: List[str]
"""A list of the names of the variables the prompt template expects."""
example_separator: str = "\n\n"
"""String separator used to join the prefix, the examples, and suffix."""
prefix: str = ""
"""A prompt template string to put before the examples."""
template_format: str = "f-string"
"""The format of the prompt template. Options are: 'f-string', 'jinja2'."""
validate_template: bool = True
"""Whether or not to try validating the template."""
@root_validator(pre=True)
def check_examples_and_selector(cls, values: Dict)
|
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|
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|
@root_validator(pre=True)
def check_examples_and_selector(cls, values: Dict) -> Dict:
"""Check that one and only one of examples/example_selector are provided."""
examples = values.get("examples", None)
example_selector = values.get("example_selector", None)
if examples and example_selector:
raise ValueError(
"Only one of 'examples' and 'example_selector' should be provided"
)
if examples is None and example_selector is None:
raise ValueError(
"One of 'examples' and 'example_selector' should be provided"
)
return values
@root_validator()
def template_is_valid(cls, values: Dict) -> Dict:
"""Check that prefix, suffix and input variables are consistent."""
if values["validate_template"]:
check_valid_template(
values["prefix"] + values["suffix"],
values["template_format"],
values["input_variables"] + list(values["partial_variables"]),
)
return values
class Config:
|
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|
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|
)
return values
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
def _get_examples(self, **kwargs: Any) -> List[dict]:
if self.examples is not None:
return self.examples
elif self.example_selector is not None:
return self.example_selector.select_examples(kwargs)
else:
raise ValueError
[docs] def format(self, **kwargs: Any) -> str:
"""Format the prompt with the inputs.
Args:
kwargs: Any arguments to be passed to the prompt template.
Returns:
A formatted string.
Example:
.. code-block:: python
prompt.format(variable1="foo")
"""
kwargs = self._merge_partial_and_user_variables(**kwargs)
# Get the examples to use.
examples = self._get_examples(**kwargs)
# Format the examples.
example_strings = [
self.example_prompt.format(**example) for example in examples
|
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|
d056f9d89ff6-3
|
self.example_prompt.format(**example) for example in examples
]
# Create the overall template.
pieces = [self.prefix, *example_strings, self.suffix]
template = self.example_separator.join([piece for piece in pieces if piece])
# Format the template with the input variables.
return DEFAULT_FORMATTER_MAPPING[self.template_format](template, **kwargs)
@property
def _prompt_type(self) -> str:
"""Return the prompt type key."""
return "few_shot"
[docs] def dict(self, **kwargs: Any) -> Dict:
"""Return a dictionary of the prompt."""
if self.example_selector:
raise ValueError("Saving an example selector is not currently supported")
return super().dict(**kwargs)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/few_shot.html
|
884ba17801a5-0
|
Source code for langchain.prompts.prompt
"""Prompt schema definition."""
from __future__ import annotations
from pathlib import Path
from string import Formatter
from typing import Any, Dict, List, Union
from pydantic import Extra, root_validator
from langchain.prompts.base import (
DEFAULT_FORMATTER_MAPPING,
StringPromptTemplate,
check_valid_template,
)
[docs]class PromptTemplate(StringPromptTemplate):
"""Schema to represent a prompt for an LLM.
Example:
.. code-block:: python
from langchain import PromptTemplate
prompt = PromptTemplate(input_variables=["foo"], template="Say {foo}")
"""
input_variables: List[str]
"""A list of the names of the variables the prompt template expects."""
template: str
"""The prompt template."""
template_format: str = "f-string"
"""The format of the prompt template. Options are: 'f-string', 'jinja2'."""
validate_template: bool = True
"""Whether or not to try validating the template."""
@property
def _prompt_type(self) -> str:
"""Return the prompt type key."""
return "prompt"
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
[docs] def format(self, **kwargs: Any) -> str:
"""Format the prompt with the inputs.
Args:
|
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with the inputs.
Args:
kwargs: Any arguments to be passed to the prompt template.
Returns:
A formatted string.
Example:
.. code-block:: python
prompt.format(variable1="foo")
"""
kwargs = self._merge_partial_and_user_variables(**kwargs)
return DEFAULT_FORMATTER_MAPPING[self.template_format](self.template, **kwargs)
@root_validator()
def template_is_valid(cls, values: Dict) -> Dict:
"""Check that template and input variables are consistent."""
if values["validate_template"]:
all_inputs = values["input_variables"] + list(values["partial_variables"])
check_valid_template(
values["template"], values["template_format"], all_inputs
)
return values
[docs] @classmethod
def from_examples(
cls,
examples: List[str],
suffix: str,
input_variables: List[str],
example_separator: str = "\n\n",
prefix: str = "",
**kwargs: Any,
) ->
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str = "",
**kwargs: Any,
) -> PromptTemplate:
"""Take examples in list format with prefix and suffix to create a prompt.
Intended to be used as a way to dynamically create a prompt from examples.
Args:
examples: List of examples to use in the prompt.
suffix: String to go after the list of examples. Should generally
set up the user's input.
input_variables: A list of variable names the final prompt template
will expect.
example_separator: The separator to use in between examples. Defaults
to two new line characters.
prefix: String that should go before any examples. Generally includes
examples. Default to an empty string.
Returns:
The final prompt generated.
"""
template = example_separator.join([prefix, *examples, suffix])
return cls(input_variables=input_variables, template=template, **kwargs)
[docs] @classmethod
def from_file(
cls, template_file: Union[str, Path], input_variables: List[str], **kwargs: Any
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Union[str, Path], input_variables: List[str], **kwargs: Any
) -> PromptTemplate:
"""Load a prompt from a file.
Args:
template_file: The path to the file containing the prompt template.
input_variables: A list of variable names the final prompt template
will expect.
Returns:
The prompt loaded from the file.
"""
with open(str(template_file), "r") as f:
template = f.read()
return cls(input_variables=input_variables, template=template, **kwargs)
[docs] @classmethod
def from_template(cls, template: str, **kwargs: Any) -> PromptTemplate:
"""Load a prompt template from a template."""
input_variables = {
v for _, v, _, _ in Formatter().parse(template) if v is not None
}
return cls(
input_variables=list(sorted(input_variables)), template=template, **kwargs
)
# For backwards compatibility.
Prompt = PromptTemplate
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
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Source code for langchain.prompts.loading
"""Load prompts from disk."""
import importlib
import json
import logging
from pathlib import Path
from typing import Union
import yaml
from langchain.output_parsers.regex import RegexParser
from langchain.prompts.base import BasePromptTemplate
from langchain.prompts.few_shot import FewShotPromptTemplate
from langchain.prompts.prompt import PromptTemplate
from langchain.utilities.loading import try_load_from_hub
URL_BASE = "https://raw.githubusercontent.com/hwchase17/langchain-hub/master/prompts/"
logger = logging.getLogger(__file__)
def load_prompt_from_config(config: dict) -> BasePromptTemplate:
"""Load prompt from Config Dict."""
if "_type" not in config:
logger.warning("No `_type` key found, defaulting to `prompt`.")
config_type = config.pop("_type", "prompt")
if config_type not in type_to_loader_dict:
raise ValueError(f"Loading {config_type} prompt not supported")
prompt_loader = type_to_loader_dict[config_type]
return prompt_loader(config)
def _load_template(var_name: str, config: dict) -> dict:
"""Load template from disk if applicable."""
# Check if template_path exists in config.
if f"{var_name}_path" in config:
# If it does, make sure template variable doesn't also exist.
if var_name in config:
raise ValueError(
f"Both `{var_name}_path` and `{var_name}` cannot be provided."
)
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cannot be provided."
)
# Pop the template path from the config.
template_path = Path(config.pop(f"{var_name}_path"))
# Load the template.
if template_path.suffix == ".txt":
with open(template_path) as f:
template = f.read()
else:
raise ValueError
# Set the template variable to the extracted variable.
config[var_name] = template
return config
def _load_examples(config: dict) -> dict:
"""Load examples if necessary."""
if isinstance(config["examples"], list):
pass
elif isinstance(config["examples"], str):
with open(config["examples"]) as f:
if config["examples"].endswith(".json"):
examples = json.load(f)
elif config["examples"].endswith((".yaml", ".yml")):
examples = yaml.safe_load(f)
else:
raise ValueError(
"Invalid file format. Only json or yaml formats are supported."
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"Invalid file format. Only json or yaml formats are supported."
)
config["examples"] = examples
else:
raise ValueError("Invalid examples format. Only list or string are supported.")
return config
def _load_output_parser(config: dict) -> dict:
"""Load output parser."""
if "output_parsers" in config:
if config["output_parsers"] is not None:
_config = config["output_parsers"]
output_parser_type = _config["_type"]
if output_parser_type == "regex_parser":
output_parser = RegexParser(**_config)
else:
raise ValueError(f"Unsupported output parser {output_parser_type}")
config["output_parsers"] = output_parser
return config
def _load_few_shot_prompt(config: dict) -> FewShotPromptTemplate:
"""Load the few shot prompt from the config."""
# Load the suffix and prefix templates.
config = _load_template("suffix", config)
config = _load_template("prefix", config)
# Load the example prompt.
if "example_prompt_path" in config:
if "example_prompt" in config:
raise ValueError(
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in config:
raise ValueError(
"Only one of example_prompt and example_prompt_path should "
"be specified."
)
config["example_prompt"] = load_prompt(config.pop("example_prompt_path"))
else:
config["example_prompt"] = load_prompt_from_config(config["example_prompt"])
# Load the examples.
config = _load_examples(config)
config = _load_output_parser(config)
return FewShotPromptTemplate(**config)
def _load_prompt(config: dict) -> PromptTemplate:
"""Load the prompt template from config."""
# Load the template from disk if necessary.
config = _load_template("template", config)
config = _load_output_parser(config)
return PromptTemplate(**config)
[docs]def load_prompt(path: Union[str, Path]) -> BasePromptTemplate:
"""Unified method for loading a prompt from LangChainHub or local fs."""
if hub_result := try_load_from_hub(
path, _load_prompt_from_file, "prompts", {"py", "json", "yaml"}
):
return hub_result
else:
return _load_prompt_from_file(path)
def _load_prompt_from_file(file: Union[str, Path]) -> BasePromptTemplate:
"""Load prompt from file."""
# Convert file to Path object.
if isinstance(file, str):
file_path =
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if isinstance(file, str):
file_path = Path(file)
else:
file_path = file
# Load from either json or yaml.
if file_path.suffix == ".json":
with open(file_path) as f:
config = json.load(f)
elif file_path.suffix == ".yaml":
with open(file_path, "r") as f:
config = yaml.safe_load(f)
elif file_path.suffix == ".py":
spec = importlib.util.spec_from_loader(
"prompt", loader=None, origin=str(file_path)
)
if spec is None:
raise ValueError("could not load spec")
helper = importlib.util.module_from_spec(spec)
with open(file_path, "rb") as f:
exec(f.read(), helper.__dict__)
if not isinstance(helper.PROMPT, BasePromptTemplate):
raise ValueError("Did not get object of type BasePromptTemplate.")
return helper.PROMPT
else:
raise ValueError(f"Got unsupported file type {file_path.suffix}")
# Load the prompt from the config now.
return load_prompt_from_config(config)
type_to_loader_dict = {
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return load_prompt_from_config(config)
type_to_loader_dict = {
"prompt": _load_prompt,
"few_shot": _load_few_shot_prompt,
# "few_shot_with_templates": _load_few_shot_with_templates_prompt,
}
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
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Source code for langchain.prompts.few_shot_with_templates
"""Prompt template that contains few shot examples."""
from typing import Any, Dict, List, Optional
from pydantic import Extra, root_validator
from langchain.prompts.base import DEFAULT_FORMATTER_MAPPING, StringPromptTemplate
from langchain.prompts.example_selector.base import BaseExampleSelector
from langchain.prompts.prompt import PromptTemplate
[docs]class FewShotPromptWithTemplates(StringPromptTemplate):
"""Prompt template that contains few shot examples."""
examples: Optional[List[dict]] = None
"""Examples to format into the prompt.
Either this or example_selector should be provided."""
example_selector: Optional[BaseExampleSelector] = None
"""ExampleSelector to choose the examples to format into the prompt.
Either this or examples should be provided."""
example_prompt: PromptTemplate
"""PromptTemplate used to format an individual example."""
suffix: StringPromptTemplate
"""A PromptTemplate to put after the examples."""
input_variables: List[str]
"""A list of the names of the variables the prompt template expects."""
example_separator: str = "\n\n"
"""String separator used to join the prefix, the examples, and suffix."""
prefix: Optional[StringPromptTemplate] = None
"""A PromptTemplate to put before the examples."""
template_format: str = "f-string"
"""The format of the prompt template. Options are: 'f-string', 'jinja2'."""
validate_template: bool = True
"""Whether or not to try validating the template."""
@root_validator(pre=True)
def check_examples_and_selector(cls, values: Dict) -> Dict:
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def check_examples_and_selector(cls, values: Dict) -> Dict:
"""Check that one and only one of examples/example_selector are provided."""
examples = values.get("examples", None)
example_selector = values.get("example_selector", None)
if examples and example_selector:
raise ValueError(
"Only one of 'examples' and 'example_selector' should be provided"
)
if examples is None and example_selector is None:
raise ValueError(
"One of 'examples' and 'example_selector' should be provided"
)
return values
@root_validator()
def template_is_valid(cls, values: Dict) -> Dict:
"""Check that prefix, suffix and input variables are consistent."""
if values["validate_template"]:
input_variables = values["input_variables"]
expected_input_variables = set(values["suffix"].input_variables)
expected_input_variables |= set(values["partial_variables"])
if values["prefix"] is not None:
expected_input_variables |= set(values["prefix"].input_variables)
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|= set(values["prefix"].input_variables)
missing_vars = expected_input_variables.difference(input_variables)
if missing_vars:
raise ValueError(
f"Got input_variables={input_variables}, but based on "
f"prefix/suffix expected {expected_input_variables}"
)
return values
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
def _get_examples(self, **kwargs: Any) -> List[dict]:
if self.examples is not None:
return self.examples
elif self.example_selector is not None:
return self.example_selector.select_examples(kwargs)
else:
raise ValueError
[docs] def format(self, **kwargs: Any) -> str:
"""Format the prompt with the inputs.
Args:
kwargs: Any arguments to be passed to the prompt template.
Returns:
A formatted string.
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A formatted string.
Example:
.. code-block:: python
prompt.format(variable1="foo")
"""
kwargs = self._merge_partial_and_user_variables(**kwargs)
# Get the examples to use.
examples = self._get_examples(**kwargs)
# Format the examples.
example_strings = [
self.example_prompt.format(**example) for example in examples
]
# Create the overall prefix.
if self.prefix is None:
prefix = ""
else:
prefix_kwargs = {
k: v for k, v in kwargs.items() if k in self.prefix.input_variables
}
for k in prefix_kwargs.keys():
kwargs.pop(k)
prefix = self.prefix.format(**prefix_kwargs)
# Create the overall suffix
suffix_kwargs = {
k: v for k, v in kwargs.items() if k in self.suffix.input_variables
}
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in self.suffix.input_variables
}
for k in suffix_kwargs.keys():
kwargs.pop(k)
suffix = self.suffix.format(
**suffix_kwargs,
)
pieces = [prefix, *example_strings, suffix]
template = self.example_separator.join([piece for piece in pieces if piece])
# Format the template with the input variables.
return DEFAULT_FORMATTER_MAPPING[self.template_format](template, **kwargs)
@property
def _prompt_type(self) -> str:
"""Return the prompt type key."""
return "few_shot_with_templates"
[docs] def dict(self, **kwargs: Any) -> Dict:
"""Return a dictionary of the prompt."""
if self.example_selector:
raise ValueError("Saving an example selector is not currently supported")
return super().dict(**kwargs)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
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Source code for langchain.prompts.chat
"""Chat prompt template."""
from __future__ import annotations
from abc import ABC, abstractmethod
from pathlib import Path
from typing import Any, Callable, List, Sequence, Tuple, Type, Union
from pydantic import BaseModel, Field
from langchain.memory.buffer import get_buffer_string
from langchain.prompts.base import BasePromptTemplate, StringPromptTemplate
from langchain.prompts.prompt import PromptTemplate
from langchain.schema import (
AIMessage,
BaseMessage,
ChatMessage,
HumanMessage,
PromptValue,
SystemMessage,
)
class BaseMessagePromptTemplate(BaseModel, ABC):
@abstractmethod
def format_messages(self, **kwargs: Any) -> List[BaseMessage]:
"""To messages."""
@property
@abstractmethod
def input_variables(self) -> List[str]:
"""Input variables for this prompt template."""
[docs]class MessagesPlaceholder(BaseMessagePromptTemplate):
"""Prompt template that assumes variable is already list of messages."""
variable_name: str
[docs] def format_messages(self, **kwargs: Any) -> List[BaseMessage]:
"""To a BaseMessage."""
value = kwargs[self.variable_name]
if not isinstance(value, list):
raise ValueError(
f"variable {self.variable_name} should be a list of base messages, "
f"got {value}"
)
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f"got {value}"
)
for v in value:
if not isinstance(v, BaseMessage):
raise ValueError(
f"variable {self.variable_name} should be a list of base messages,"
f" got {value}"
)
return value
@property
def input_variables(self) -> List[str]:
"""Input variables for this prompt template."""
return [self.variable_name]
class BaseStringMessagePromptTemplate(BaseMessagePromptTemplate, ABC):
prompt: StringPromptTemplate
additional_kwargs: dict = Field(default_factory=dict)
@classmethod
def from_template(cls, template: str, **kwargs: Any) -> BaseMessagePromptTemplate:
prompt = PromptTemplate.from_template(template)
return cls(prompt=prompt, **kwargs)
@abstractmethod
def format(self, **kwargs: Any) -> BaseMessage:
"""To a BaseMessage."""
def format_messages(self, **kwargs: Any) -> List[BaseMessage]:
return [self.format(**kwargs)]
@property
def input_variables(self) -> List[str]:
return self.prompt.input_variables
class
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|
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|
-> List[str]:
return self.prompt.input_variables
class ChatMessagePromptTemplate(BaseStringMessagePromptTemplate):
role: str
def format(self, **kwargs: Any) -> BaseMessage:
text = self.prompt.format(**kwargs)
return ChatMessage(
content=text, role=self.role, additional_kwargs=self.additional_kwargs
)
class HumanMessagePromptTemplate(BaseStringMessagePromptTemplate):
def format(self, **kwargs: Any) -> BaseMessage:
text = self.prompt.format(**kwargs)
return HumanMessage(content=text, additional_kwargs=self.additional_kwargs)
class AIMessagePromptTemplate(BaseStringMessagePromptTemplate):
def format(self, **kwargs: Any) -> BaseMessage:
text = self.prompt.format(**kwargs)
return AIMessage(content=text, additional_kwargs=self.additional_kwargs)
class SystemMessagePromptTemplate(BaseStringMessagePromptTemplate):
def format(self, **kwargs: Any) -> BaseMessage:
text = self.prompt.format(**kwargs)
return SystemMessage(content=text, additional_kwargs=self.additional_kwargs)
class ChatPromptValue(PromptValue):
messages: List[BaseMessage]
def to_string(self) -> str:
"""Return prompt as string."""
return get_buffer_string(self.messages)
def to_messages(self) -> List[BaseMessage]:
"""Return prompt as messages."""
return self.messages
[docs]class BaseChatPromptTemplate(BasePromptTemplate,
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return self.messages
[docs]class BaseChatPromptTemplate(BasePromptTemplate, ABC):
[docs] def format(self, **kwargs: Any) -> str:
return self.format_prompt(**kwargs).to_string()
[docs] def format_prompt(self, **kwargs: Any) -> PromptValue:
messages = self.format_messages(**kwargs)
return ChatPromptValue(messages=messages)
[docs] @abstractmethod
def format_messages(self, **kwargs: Any) -> List[BaseMessage]:
"""Format kwargs into a list of messages."""
[docs]class ChatPromptTemplate(BaseChatPromptTemplate, ABC):
input_variables: List[str]
messages: List[Union[BaseMessagePromptTemplate, BaseMessage]]
@classmethod
def from_role_strings(
cls, string_messages: List[Tuple[str, str]]
) -> ChatPromptTemplate:
messages = [
ChatMessagePromptTemplate(
content=PromptTemplate.from_template(template), role=role
)
for role, template in string_messages
]
return cls.from_messages(messages)
@classmethod
def from_strings(
cls, string_messages: List[Tuple[Type[BaseMessagePromptTemplate], str]]
) -> ChatPromptTemplate:
messages = [
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-> ChatPromptTemplate:
messages = [
role(content=PromptTemplate.from_template(template))
for role, template in string_messages
]
return cls.from_messages(messages)
@classmethod
def from_messages(
cls, messages: Sequence[Union[BaseMessagePromptTemplate, BaseMessage]]
) -> ChatPromptTemplate:
input_vars = set()
for message in messages:
if isinstance(message, BaseMessagePromptTemplate):
input_vars.update(message.input_variables)
return cls(input_variables=list(input_vars), messages=messages)
[docs] def format(self, **kwargs: Any) -> str:
return self.format_prompt(**kwargs).to_string()
[docs] def format_messages(self, **kwargs: Any) -> List[BaseMessage]:
kwargs = self._merge_partial_and_user_variables(**kwargs)
result = []
for message_template in self.messages:
if isinstance(message_template, BaseMessage):
result.extend([message_template])
elif isinstance(message_template, BaseMessagePromptTemplate):
rel_params = {
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rel_params = {
k: v
for k, v in kwargs.items()
if k in message_template.input_variables
}
message = message_template.format_messages(**rel_params)
result.extend(message)
else:
raise ValueError(f"Unexpected input: {message_template}")
return result
[docs] def partial(self, **kwargs: Union[str, Callable[[], str]]) -> BasePromptTemplate:
raise NotImplementedError
@property
def _prompt_type(self) -> str:
raise NotImplementedError
[docs] def save(self, file_path: Union[Path, str]) -> None:
raise NotImplementedError
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
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aad32298d3ae-0
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Source code for langchain.prompts.example_selector.semantic_similarity
"""Example selector that selects examples based on SemanticSimilarity."""
from __future__ import annotations
from typing import Any, Dict, List, Optional, Type
from pydantic import BaseModel, Extra
from langchain.embeddings.base import Embeddings
from langchain.prompts.example_selector.base import BaseExampleSelector
from langchain.vectorstores.base import VectorStore
def sorted_values(values: Dict[str, str]) -> List[Any]:
"""Return a list of values in dict sorted by key."""
return [values[val] for val in sorted(values)]
[docs]class SemanticSimilarityExampleSelector(BaseExampleSelector, BaseModel):
"""Example selector that selects examples based on SemanticSimilarity."""
vectorstore: VectorStore
"""VectorStore than contains information about examples."""
k: int = 4
"""Number of examples to select."""
example_keys: Optional[List[str]] = None
"""Optional keys to filter examples to."""
input_keys: Optional[List[str]] = None
"""Optional keys to filter input to. If provided, the search is based on
the input variables instead of all variables."""
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
[docs] def add_example(self, example: Dict[str, str]) -> str:
"""Add new example to vectorstore."""
if self.input_keys:
string_example = " ".join(
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= " ".join(
sorted_values({key: example[key] for key in self.input_keys})
)
else:
string_example = " ".join(sorted_values(example))
ids = self.vectorstore.add_texts([string_example], metadatas=[example])
return ids[0]
[docs] def select_examples(self, input_variables: Dict[str, str]) -> List[dict]:
"""Select which examples to use based on semantic similarity."""
# Get the docs with the highest similarity.
if self.input_keys:
input_variables = {key: input_variables[key] for key in self.input_keys}
query = " ".join(sorted_values(input_variables))
example_docs = self.vectorstore.similarity_search(query, k=self.k)
# Get the examples from the metadata.
# This assumes that examples are stored in metadata.
examples = [dict(e.metadata) for e in example_docs]
# If example keys are provided, filter examples to those keys.
if self.example_keys:
examples = [{k: eg[k] for k in self.example_keys} for eg in examples]
return examples
[docs] @classmethod
def from_examples(
cls,
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@classmethod
def from_examples(
cls,
examples: List[dict],
embeddings: Embeddings,
vectorstore_cls: Type[VectorStore],
k: int = 4,
input_keys: Optional[List[str]] = None,
**vectorstore_cls_kwargs: Any,
) -> SemanticSimilarityExampleSelector:
"""Create k-shot example selector using example list and embeddings.
Reshuffles examples dynamically based on query similarity.
Args:
examples: List of examples to use in the prompt.
embeddings: An initialized embedding API interface, e.g. OpenAIEmbeddings().
vectorstore_cls: A vector store DB interface class, e.g. FAISS.
k: Number of examples to select
input_keys: If provided, the search is based on the input variables
instead of all variables.
vectorstore_cls_kwargs: optional kwargs containing url for vector store
Returns:
The ExampleSelector instantiated, backed by a vector store.
"""
if input_keys:
string_examples = [
|
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|
aad32298d3ae-3
|
string_examples = [
" ".join(sorted_values({k: eg[k] for k in input_keys}))
for eg in examples
]
else:
string_examples = [" ".join(sorted_values(eg)) for eg in examples]
vectorstore = vectorstore_cls.from_texts(
string_examples, embeddings, metadatas=examples, **vectorstore_cls_kwargs
)
return cls(vectorstore=vectorstore, k=k, input_keys=input_keys)
[docs]class MaxMarginalRelevanceExampleSelector(SemanticSimilarityExampleSelector):
"""ExampleSelector that selects examples based on Max Marginal Relevance.
This was shown to improve performance in this paper:
https://arxiv.org/pdf/2211.13892.pdf
"""
fetch_k: int = 20
"""Number of examples to fetch to rerank."""
[docs] def select_examples(self, input_variables: Dict[str, str]) -> List[dict]:
"""Select which examples to use based on semantic similarity."""
# Get the docs with the highest similarity.
if self.input_keys:
input_variables = {key: input_variables[key] for key in self.input_keys}
query = " ".join(sorted_values(input_variables))
|
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|
aad32298d3ae-4
|
query = " ".join(sorted_values(input_variables))
example_docs = self.vectorstore.max_marginal_relevance_search(
query, k=self.k, fetch_k=self.fetch_k
)
# Get the examples from the metadata.
# This assumes that examples are stored in metadata.
examples = [dict(e.metadata) for e in example_docs]
# If example keys are provided, filter examples to those keys.
if self.example_keys:
examples = [{k: eg[k] for k in self.example_keys} for eg in examples]
return examples
[docs] @classmethod
def from_examples(
cls,
examples: List[dict],
embeddings: Embeddings,
vectorstore_cls: Type[VectorStore],
k: int = 4,
input_keys: Optional[List[str]] = None,
fetch_k: int = 20,
**vectorstore_cls_kwargs: Any,
) -> MaxMarginalRelevanceExampleSelector:
"""Create k-shot example selector using example list and embeddings.
Reshuffles examples dynamically based on query similarity.
Args:
examples: List of examples to use in the
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/example_selector/semantic_similarity.html
|
aad32298d3ae-5
|
examples: List of examples to use in the prompt.
embeddings: An iniialized embedding API interface, e.g. OpenAIEmbeddings().
vectorstore_cls: A vector store DB interface class, e.g. FAISS.
k: Number of examples to select
input_keys: If provided, the search is based on the input variables
instead of all variables.
vectorstore_cls_kwargs: optional kwargs containing url for vector store
Returns:
The ExampleSelector instantiated, backed by a vector store.
"""
if input_keys:
string_examples = [
" ".join(sorted_values({k: eg[k] for k in input_keys}))
for eg in examples
]
else:
string_examples = [" ".join(sorted_values(eg)) for eg in examples]
vectorstore = vectorstore_cls.from_texts(
string_examples, embeddings, metadatas=examples, **vectorstore_cls_kwargs
)
return cls(vectorstore=vectorstore,
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/example_selector/semantic_similarity.html
|
aad32298d3ae-6
|
)
return cls(vectorstore=vectorstore, k=k, fetch_k=fetch_k, input_keys=input_keys)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/example_selector/semantic_similarity.html
|
920447d5187b-0
|
Source code for langchain.prompts.example_selector.length_based
"""Select examples based on length."""
import re
from typing import Callable, Dict, List
from pydantic import BaseModel, validator
from langchain.prompts.example_selector.base import BaseExampleSelector
from langchain.prompts.prompt import PromptTemplate
def _get_length_based(text: str) -> int:
return len(re.split("\n| ", text))
[docs]class LengthBasedExampleSelector(BaseExampleSelector, BaseModel):
"""Select examples based on length."""
examples: List[dict]
"""A list of the examples that the prompt template expects."""
example_prompt: PromptTemplate
"""Prompt template used to format the examples."""
get_text_length: Callable[[str], int] = _get_length_based
"""Function to measure prompt length. Defaults to word count."""
max_length: int = 2048
"""Max length for the prompt, beyond which examples are cut."""
example_text_lengths: List[int] = [] #: :meta private:
[docs] def add_example(self, example: Dict[str, str]) -> None:
"""Add new example to list."""
self.examples.append(example)
string_example = self.example_prompt.format(**example)
self.example_text_lengths.append(self.get_text_length(string_example))
@validator("example_text_lengths", always=True)
def calculate_example_text_lengths(cls, v: List[int], values: Dict) -> List[int]:
"""Calculate text lengths if they don't exist."""
# Check if text lengths were passed in
if v:
|
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|
920447d5187b-1
|
# Check if text lengths were passed in
if v:
return v
# If they were not, calculate them
example_prompt = values["example_prompt"]
get_text_length = values["get_text_length"]
string_examples = [example_prompt.format(**eg) for eg in values["examples"]]
return [get_text_length(eg) for eg in string_examples]
[docs] def select_examples(self, input_variables: Dict[str, str]) -> List[dict]:
"""Select which examples to use based on the input lengths."""
inputs = " ".join(input_variables.values())
remaining_length = self.max_length - self.get_text_length(inputs)
i = 0
examples = []
while remaining_length > 0 and i < len(self.examples):
new_length = remaining_length - self.example_text_lengths[i]
if new_length < 0:
break
else:
examples.append(self.examples[i])
remaining_length = new_length
i += 1
return examples
By Harrison Chase
©
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/example_selector/length_based.html
|
920447d5187b-2
|
return examples
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/prompts/example_selector/length_based.html
|
bf6839f96c41-0
|
Source code for langchain.llms.huggingface_hub
"""Wrapper around HuggingFace APIs."""
from typing import Any, Dict, List, Mapping, Optional
from pydantic import Extra, root_validator
from langchain.llms.base import LLM
from langchain.llms.utils import enforce_stop_tokens
from langchain.utils import get_from_dict_or_env
DEFAULT_REPO_ID = "gpt2"
VALID_TASKS = ("text2text-generation", "text-generation")
[docs]class HuggingFaceHub(LLM):
"""Wrapper around HuggingFaceHub models.
To use, you should have the ``huggingface_hub`` python package installed, and the
environment variable ``HUGGINGFACEHUB_API_TOKEN`` set with your API token, or pass
it as a named parameter to the constructor.
Only supports `text-generation` and `text2text-generation` for now.
Example:
.. code-block:: python
from langchain.llms import HuggingFaceHub
hf = HuggingFaceHub(repo_id="gpt2", huggingfacehub_api_token="my-api-key")
"""
client: Any #: :meta private:
repo_id: str = DEFAULT_REPO_ID
"""Model name to use."""
task: Optional[str] = None
"""Task to call the model with. Should be a task that returns `generated_text`."""
model_kwargs: Optional[dict] = None
"""Key word arguments to pass to the model."""
huggingfacehub_api_token: Optional[str] = None
class Config:
|
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|
bf6839f96c41-1
|
Optional[str] = None
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
@root_validator()
def validate_environment(cls, values: Dict) -> Dict:
"""Validate that api key and python package exists in environment."""
huggingfacehub_api_token = get_from_dict_or_env(
values, "huggingfacehub_api_token", "HUGGINGFACEHUB_API_TOKEN"
)
try:
from huggingface_hub.inference_api import InferenceApi
repo_id = values["repo_id"]
client = InferenceApi(
repo_id=repo_id,
token=huggingfacehub_api_token,
task=values.get("task"),
)
if client.task not in VALID_TASKS:
raise ValueError(
f"Got invalid task {client.task}, "
f"currently only {VALID_TASKS} are supported"
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/huggingface_hub.html
|
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|
are supported"
)
values["client"] = client
except ImportError:
raise ValueError(
"Could not import huggingface_hub python package. "
"Please install it with `pip install huggingface_hub`."
)
return values
@property
def _identifying_params(self) -> Mapping[str, Any]:
"""Get the identifying parameters."""
_model_kwargs = self.model_kwargs or {}
return {
**{"repo_id": self.repo_id, "task": self.task},
**{"model_kwargs": _model_kwargs},
}
@property
def _llm_type(self) -> str:
"""Return type of llm."""
return "huggingface_hub"
def _call(self, prompt: str, stop: Optional[List[str]] = None) -> str:
"""Call out to HuggingFace Hub's inference endpoint.
Args:
prompt: The prompt to pass into the model.
stop: Optional list of stop words to use when generating.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/huggingface_hub.html
|
bf6839f96c41-3
|
stop: Optional list of stop words to use when generating.
Returns:
The string generated by the model.
Example:
.. code-block:: python
response = hf("Tell me a joke.")
"""
_model_kwargs = self.model_kwargs or {}
response = self.client(inputs=prompt, params=_model_kwargs)
if "error" in response:
raise ValueError(f"Error raised by inference API: {response['error']}")
if self.client.task == "text-generation":
# Text generation return includes the starter text.
text = response[0]["generated_text"][len(prompt) :]
elif self.client.task == "text2text-generation":
text = response[0]["generated_text"]
else:
raise ValueError(
f"Got invalid task {self.client.task}, "
f"currently only {VALID_TASKS} are supported"
)
if stop is not None:
# This is a bit hacky, but I can't
|
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|
bf6839f96c41-4
|
# This is a bit hacky, but I can't figure out a better way to enforce
# stop tokens when making calls to huggingface_hub.
text = enforce_stop_tokens(text, stop)
return text
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/huggingface_hub.html
|
c604897a2b76-0
|
Source code for langchain.llms.self_hosted
"""Run model inference on self-hosted remote hardware."""
import importlib.util
import logging
import pickle
from typing import Any, Callable, List, Mapping, Optional
from pydantic import Extra
from langchain.llms.base import LLM
from langchain.llms.utils import enforce_stop_tokens
logger = logging.getLogger()
def _generate_text(
pipeline: Any,
prompt: str,
*args: Any,
stop: Optional[List[str]] = None,
**kwargs: Any,
) -> str:
"""Inference function to send to the remote hardware.
Accepts a pipeline callable (or, more likely,
a key pointing to the model on the cluster's object store)
and returns text predictions for each document
in the batch.
"""
text = pipeline(prompt, *args, **kwargs)
if stop is not None:
text = enforce_stop_tokens(text, stop)
return text
def _send_pipeline_to_device(pipeline: Any, device: int) -> Any:
"""Send a pipeline to a device on the cluster."""
if isinstance(pipeline, str):
with open(pipeline, "rb") as f:
pipeline = pickle.load(f)
if importlib.util.find_spec("torch") is not None:
import torch
cuda_device_count = torch.cuda.device_count()
if device < -1 or (device >= cuda_device_count):
raise ValueError(
|
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|
c604897a2b76-1
|
raise ValueError(
f"Got device=={device}, "
f"device is required to be within [-1, {cuda_device_count})"
)
if device < 0 and cuda_device_count > 0:
logger.warning(
"Device has %d GPUs available. "
"Provide device={deviceId} to `from_model_id` to use available"
"GPUs for execution. deviceId is -1 for CPU and "
"can be a positive integer associated with CUDA device id.",
cuda_device_count,
)
pipeline.device = torch.device(device)
pipeline.model = pipeline.model.to(pipeline.device)
return pipeline
[docs]class SelfHostedPipeline(LLM):
"""Run model inference on self-hosted remote hardware.
Supported hardware includes auto-launched instances on AWS, GCP, Azure,
and Lambda, as well as servers specified
by IP address and SSH credentials (such as on-prem, or another
cloud like Paperspace, Coreweave, etc.).
To use, you should have the ``runhouse`` python package
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/self_hosted.html
|
c604897a2b76-2
|
etc.).
To use, you should have the ``runhouse`` python package installed.
Example for custom pipeline and inference functions:
.. code-block:: python
from langchain.llms import SelfHostedPipeline
from transformers import AutoModelForCausalLM, AutoTokenizer, pipeline
import runhouse as rh
def load_pipeline():
tokenizer = AutoTokenizer.from_pretrained("gpt2")
model = AutoModelForCausalLM.from_pretrained("gpt2")
return pipeline(
"text-generation", model=model, tokenizer=tokenizer,
max_new_tokens=10
)
def inference_fn(pipeline, prompt, stop = None):
return pipeline(prompt)[0]["generated_text"]
gpu = rh.cluster(name="rh-a10x", instance_type="A100:1")
llm = SelfHostedPipeline(
model_load_fn=load_pipeline,
|
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|
c604897a2b76-3
|
model_load_fn=load_pipeline,
hardware=gpu,
model_reqs=model_reqs, inference_fn=inference_fn
)
Example for <2GB model (can be serialized and sent directly to the server):
.. code-block:: python
from langchain.llms import SelfHostedPipeline
import runhouse as rh
gpu = rh.cluster(name="rh-a10x", instance_type="A100:1")
my_model = ...
llm = SelfHostedPipeline.from_pipeline(
pipeline=my_model,
hardware=gpu,
model_reqs=["./", "torch", "transformers"],
)
Example passing model path for larger models:
.. code-block:: python
from langchain.llms import SelfHostedPipeline
import runhouse as rh
import pickle
from transformers import pipeline
generator = pipeline(model="gpt2")
|
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|
c604897a2b76-4
|
generator = pipeline(model="gpt2")
rh.blob(pickle.dumps(generator), path="models/pipeline.pkl"
).save().to(gpu, path="models")
llm = SelfHostedPipeline.from_pipeline(
pipeline="models/pipeline.pkl",
hardware=gpu,
model_reqs=["./", "torch", "transformers"],
)
"""
pipeline_ref: Any #: :meta private:
client: Any #: :meta private:
inference_fn: Callable = _generate_text #: :meta private:
"""Inference function to send to the remote hardware."""
hardware: Any
"""Remote hardware to send the inference function to."""
model_load_fn: Callable
"""Function to load the model remotely on the server."""
load_fn_kwargs: Optional[dict] = None
"""Key word arguments to pass to the model load function."""
model_reqs: List[str] = ["./", "torch"]
"""Requirements to install on hardware to inference the model."""
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
def __init__(self, **kwargs: Any):
"""Init the pipeline with an auxiliary function.
|
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|
c604897a2b76-5
|
Any):
"""Init the pipeline with an auxiliary function.
The load function must be in global scope to be imported
and run on the server, i.e. in a module and not a REPL or closure.
Then, initialize the remote inference function.
"""
super().__init__(**kwargs)
try:
import runhouse as rh
except ImportError:
raise ValueError(
"Could not import runhouse python package. "
"Please install it with `pip install runhouse`."
)
remote_load_fn = rh.function(fn=self.model_load_fn).to(
self.hardware, reqs=self.model_reqs
)
_load_fn_kwargs = self.load_fn_kwargs or {}
self.pipeline_ref = remote_load_fn.remote(**_load_fn_kwargs)
self.client = rh.function(fn=self.inference_fn).to(
self.hardware, reqs=self.model_reqs
)
[docs] @classmethod
def from_pipeline(
cls,
pipeline: Any,
hardware: Any,
|
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|
c604897a2b76-6
|
pipeline: Any,
hardware: Any,
model_reqs: Optional[List[str]] = None,
device: int = 0,
**kwargs: Any,
) -> LLM:
"""Init the SelfHostedPipeline from a pipeline object or string."""
if not isinstance(pipeline, str):
logger.warning(
"Serializing pipeline to send to remote hardware. "
"Note, it can be quite slow"
"to serialize and send large models with each execution. "
"Consider sending the pipeline"
"to the cluster and passing the path to the pipeline instead."
)
load_fn_kwargs = {"pipeline": pipeline, "device": device}
return cls(
load_fn_kwargs=load_fn_kwargs,
model_load_fn=_send_pipeline_to_device,
hardware=hardware,
model_reqs=["transformers", "torch"] + (model_reqs or []),
**kwargs,
)
@property
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/self_hosted.html
|
c604897a2b76-7
|
**kwargs,
)
@property
def _identifying_params(self) -> Mapping[str, Any]:
"""Get the identifying parameters."""
return {
**{"hardware": self.hardware},
}
@property
def _llm_type(self) -> str:
return "self_hosted_llm"
def _call(self, prompt: str, stop: Optional[List[str]] = None) -> str:
return self.client(pipeline=self.pipeline_ref, prompt=prompt, stop=stop)
By Harrison Chase
© Copyright 2023, Harrison Chase.
Last updated on Apr 18, 2023.
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/self_hosted.html
|
4449501757a2-0
|
Source code for langchain.llms.writer
"""Wrapper around Writer APIs."""
from typing import Any, Dict, List, Mapping, Optional
import requests
from pydantic import Extra, root_validator
from langchain.llms.base import LLM
from langchain.llms.utils import enforce_stop_tokens
from langchain.utils import get_from_dict_or_env
[docs]class Writer(LLM):
"""Wrapper around Writer large language models.
To use, you should have the environment variable ``WRITER_API_KEY``
set with your API key.
Example:
.. code-block:: python
from langchain import Writer
writer = Writer(model_id="palmyra-base")
"""
model_id: str = "palmyra-base"
"""Model name to use."""
tokens_to_generate: int = 24
"""Max number of tokens to generate."""
logprobs: bool = False
"""Whether to return log probabilities."""
temperature: float = 1.0
"""What sampling temperature to use."""
length: int = 256
"""The maximum number of tokens to generate in the completion."""
top_p: float = 1.0
"""Total probability mass of tokens to consider at each step."""
top_k: int = 1
"""The number of highest probability vocabulary tokens to
keep for top-k-filtering."""
repetition_penalty: float = 1.0
"""Penalizes repeated tokens according to frequency."""
random_seed: int = 0
"""The model generates
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/writer.html
|
4449501757a2-1
|
frequency."""
random_seed: int = 0
"""The model generates random results.
Changing the random seed alone will produce a different response
with similar characteristics. It is possible to reproduce results
by fixing the random seed (assuming all other hyperparameters
are also fixed)"""
beam_search_diversity_rate: float = 1.0
"""Only applies to beam search, i.e. when the beam width is >1.
A higher value encourages beam search to return a more diverse
set of candidates"""
beam_width: Optional[int] = None
"""The number of concurrent candidates to keep track of during
beam search"""
length_pentaly: float = 1.0
"""Only applies to beam search, i.e. when the beam width is >1.
Larger values penalize long candidates more heavily, thus preferring
shorter candidates"""
writer_api_key: Optional[str] = None
stop: Optional[List[str]] = None
"""Sequences when completion generation will stop"""
base_url: Optional[str] = None
"""Base url to use, if None decides based on model name."""
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
@root_validator()
def validate_environment(cls, values: Dict) -> Dict:
"""Validate that api key exists in environment."""
writer_api_key = get_from_dict_or_env(
values, "writer_api_key",
|
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|
4449501757a2-2
|
values, "writer_api_key", "WRITER_API_KEY"
)
values["writer_api_key"] = writer_api_key
return values
@property
def _default_params(self) -> Mapping[str, Any]:
"""Get the default parameters for calling Writer API."""
return {
"tokens_to_generate": self.tokens_to_generate,
"stop": self.stop,
"logprobs": self.logprobs,
"temperature": self.temperature,
"top_p": self.top_p,
"top_k": self.top_k,
"repetition_penalty": self.repetition_penalty,
"random_seed": self.random_seed,
"beam_search_diversity_rate": self.beam_search_diversity_rate,
"beam_width": self.beam_width,
"length_pentaly": self.length_pentaly,
}
@property
def _identifying_params(self) -> Mapping[str, Any]:
"""Get the identifying parameters."""
return {**{"model_id": self.model_id}, **self._default_params}
|
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|
4449501757a2-3
|
return {**{"model_id": self.model_id}, **self._default_params}
@property
def _llm_type(self) -> str:
"""Return type of llm."""
return "writer"
def _call(self, prompt: str, stop: Optional[List[str]] = None) -> str:
"""Call out to Writer's complete endpoint.
Args:
prompt: The prompt to pass into the model.
stop: Optional list of stop words to use when generating.
Returns:
The string generated by the model.
Example:
.. code-block:: python
response = Writer("Tell me a joke.")
"""
if self.base_url is not None:
base_url = self.base_url
else:
base_url = (
"https://api.llm.writer.com/v1/models/{self.model_id}/completions"
)
response = requests.post(
url=base_url,
headers={
|
https:///langchain-cn.readthedocs.io/en/latest/_modules/langchain/llms/writer.html
|
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