Ela279/langchain_docs huggingface dataset:
.rst
.pdf
API References
API References#
Full documentation on all methods, classes, and APIs in LangChain.
Models
Prompts
Indexes
Memory
Chains
Agents
Utilities
Experimental Modules

Installation

Models
By Harrison Chase
.rst
.pdf
Integrations
 Contents 
Integrations by Module
All Integrations
Integrations#
LangChain integrates with many LLMs, systems, and products.
Integrations by Module#
Integrations grouped by the core LangChain module they map to:
LLM Providers
Chat Model Providers
Text Embedding Model Providers
Document Loader Integrations
Text Splitter Integrations
Vectorstore Providers
Retriever Providers
Tool Providers
Toolkit Integrations
All Integrations#
A comprehensive list of LLMs, systems, and products integrated with LangChain:
AI21 Labs
Aim
AnalyticDB
Anyscale
Apify
AtlasDB
Banana
Beam
CerebriumAI
Chroma
ClearML Integration
Cohere
Comet
Databerry
Databricks
DeepInfra
Deep Lake
Docugami
Advantages vs Other Chunking Techniques
ForefrontAI
Google Search
Google Serper
GooseAI
GPT4All
Graphsignal
Hazy Research
Helicone
Hugging Face
Jina
LanceDB
Llama.cpp
Metal
Milvus
MLflow
Modal
MyScale
NLPCloud
OpenAI
OpenSearch
OpenWeatherMap API
Petals
PGVector
Pinecone
PipelineAI
Prediction Guard
PromptLayer
Psychic
Advantages vs Other Document Loaders
Qdrant
Rebuff: Prompt Injection Detection with LangChain
Redis
Replicate
Runhouse
RWKV-4
SearxNG Search API
SerpAPI
StochasticAI
Tair
Unstructured
Vectara
Weights & Biases
Weaviate
WhyLabs Integration
Wolfram Alpha Wrapper
Writer
Yeager.ai
Zilliz

Experimental Modules

AI21 Labs
 Contents
Zilliz

Experimental Modules

AI21 Labs
 Contents
  
Integrations by Module
All Integrations
By Harrison Chase
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By Harrison Chase
Locally Hosted Setup
 Contents 
Installation
Environment Setup
Locally Hosted Setup#
This page contains instructions for installing and then setting up the environment to use the locally hosted version of tracing.
Installation#
Ensure you have Docker installed (see Get Docker) and that it’s running.
Install the latest version of langchain: pip install langchain or pip install langchain -U to upgrade your
existing version.
Run langchain-server. This command was installed automatically when you ran the above command (pip install langchain).
This will spin up the server in the terminal, hosted on port 4137 by default.
Once you see the terminal
output langchain-langchain-frontend-1 | ➜ Local: [http://localhost:4173/](http://localhost:4173/), navigate
to http://localhost:4173/
You should see a page with your tracing sessions. See the overview page for a walkthrough of the UI.
Currently, trace data is not guaranteed to be persisted between runs of langchain-server. If you want to
persist your data, you can mount a volume to the Docker container. See the Docker docs for more info.
To stop the server, press Ctrl+C in the terminal where you ran langchain-server.
Environment Setup#
After installation, you must now set up your environment to use tracing.
This can be done by setting an environment variable in your terminal by running export LANGCHAIN_HANDLER=langchain.
You can also do this by adding the below snippet to the top of every script. IMPORTANT: this must go at the VERY TOP of your script, before you import anything from langchain.
import os
os.environ["LANGCHAIN_HANDLER"] = "langchain"
 Contents
  
Installation
Environment Setup
By Harrison Chase
By Harrison Chase
Cloud Hosted Setup
 Contents 
Installation
Environment Setup
Cloud Hosted Setup#
We offer a hosted version of tracing at langchainplus.vercel.app. You can use this to view traces from your run without having to run the server locally.
Note: we are currently only offering this to a limited number of users. The hosted platform is VERY alpha, in active development, and data might be dropped at any time. Don’t depend on data being persisted in the system long term and don’t log traces that may contain sensitive information. If you’re interested in using the hosted platform, please fill out the form here.
Installation#
Login to the system and click “API Key” in the top right corner. Generate a new key and keep it safe. You will need it to authenticate with the system.
Environment Setup#
After installation, you must now set up your environment to use tracing.
This can be done by setting an environment variable in your terminal by running export LANGCHAIN_HANDLER=langchain.
You can also do this by adding the below snippet to the top of every script. IMPORTANT: this must go at the VERY TOP of your script, before you import anything from langchain.
import os
os.environ["LANGCHAIN_HANDLER"] = "langchain"
You will also need to set an environment variable to specify the endpoint and your API key. This can be done with the following environment variables:
LANGCHAIN_ENDPOINT = “https://langchain-api-gateway-57eoxz8z.uc.gateway.dev”
LANGCHAIN_API_KEY - set this to the API key you generated during installation.
An example of adding all relevant environment variables is below:
import os
os.environ["LANGCHAIN_HANDLER"] = "langchain"
os.environ["LANGCHAIN_ENDPOINT"] = "https://langchain-api-gateway-57eoxz8z.uc.gateway.dev"
os.environ["LANGCHAIN_API_KEY"] = "my_api_key"  # Don't commit this to your repo! Better to set it in your terminal.
 Contents
  
Installation
Environment Setup
By Harrison Chase
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 __future__ import annotations
from typing import Any, Dict, Iterable, 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: Iterable[str],
        metadatas: Optional[Iterable[dict]] = None,
        tfidf_params: Optional[Dict[str, Any]] = None,
        **kwargs: Any,
    ) -> TFIDFRetriever:
        try:
            from sklearn.feature_extraction.text import TfidfVectorizer
        except ImportError:
            raise ImportError(
                "Could not import scikit-learn, please install with `pip install "
                "scikit-learn`."
            )
        tfidf_params = tfidf_params or {}
        vectorizer = TfidfVectorizer(**tfidf_params)
        tfidf_array = vectorizer.fit_transform(texts)
        metadatas = metadatas or ({} for _ in texts)
        docs = [Document(page_content=t, metadata=m) for t, m in zip(texts, metadatas)]
return cls(vectorizer=vectorizer, docs=docs, tfidf_array=tfidf_array, **kwargs)
[docs]    @classmethod
    def from_documents(
        cls,
        documents: Iterable[Document],
        *,
        tfidf_params: Optional[Dict[str, Any]] = None,
        **kwargs: Any,
    ) -> TFIDFRetriever:
        texts, metadatas = zip(*((d.page_content, d.metadata) for d in documents))
        return cls.from_texts(
            texts=texts, tfidf_params=tfidf_params, metadatas=metadatas, **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,)
        )  # 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
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(
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
Source code for langchain.retrievers.wikipedia
from typing import List
from langchain.schema import BaseRetriever, Document
from langchain.utilities.wikipedia import WikipediaAPIWrapper
[docs]class WikipediaRetriever(BaseRetriever, WikipediaAPIWrapper):
    """
    It is effectively a wrapper for WikipediaAPIWrapper.
    It wraps load() to get_relevant_documents().
    It uses all WikipediaAPIWrapper arguments without any change.
    """
[docs]    def get_relevant_documents(self, query: str) -> List[Document]:
        return self.load(query=query)
[docs]    async def aget_relevant_documents(self, query: str) -> List[Document]:
        raise NotImplementedError
By Harrison Chase
Source code for langchain.retrievers.knn
"""KNN 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 KNNRetriever(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
    ) -> KNNRetriever:
        index = create_index(texts, embeddings)
        return cls(embeddings=embeddings, index=index, texts=texts, **kwargs)
[docs]    def get_relevant_documents(self, query: str) -> List[Document]:
        query_embeds = np.array(self.embeddings.embed_query(query))
        # calc L2 norm
        index_embeds = self.index / np.sqrt((self.index**2).sum(1, keepdims=True))
        query_embeds = query_embeds / np.sqrt((query_embeds**2).sum())
        similarities = index_embeds.dot(query_embeds)
similarities = index_embeds.dot(query_embeds)
        sorted_ix = np.argsort(-similarities)
        denominator = np.max(similarities) - np.min(similarities) + 1e-6
        normalized_similarities = (similarities - np.min(similarities)) / denominator
        top_k_results = []
        for row in sorted_ix[0 : self.k]:
            if (
                self.relevancy_threshold is None
                or normalized_similarities[row] >= self.relevancy_threshold
            ):
                top_k_results.append(Document(page_content=self.texts[row]))
        return top_k_results
[docs]    async def aget_relevant_documents(self, query: str) -> List[Document]:
        raise NotImplementedError
By Harrison Chase
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
Source code for langchain.retrievers.zep
from __future__ import annotations
from typing import TYPE_CHECKING, List, Optional
from langchain.schema import BaseRetriever, Document
if TYPE_CHECKING:
    from zep_python import SearchResult
[docs]class ZepRetriever(BaseRetriever):
    """A Retriever implementation for the Zep long-term memory store. Search your
    user's long-term chat history with Zep.
    Note: You will need to provide the user's `session_id` to use this retriever.
    More on Zep:
    Zep provides long-term conversation storage for LLM apps. The server stores,
    summarizes, embeds, indexes, and enriches conversational AI chat
    histories, and exposes them via simple, low-latency APIs.
    For server installation instructions, see:
    https://getzep.github.io/deployment/quickstart/
    """
    def __init__(
        self,
        session_id: str,
        url: str,
        top_k: Optional[int] = None,
    ):
        try:
            from zep_python import ZepClient
        except ImportError:
            raise ValueError(
                "Could not import zep-python package. "
                "Please install it with `pip install zep-python`."
            )
        self.zep_client = ZepClient(base_url=url)
        self.session_id = session_id
        self.top_k = top_k
    def _search_result_to_doc(self, results: List[SearchResult]) -> List[Document]:
        return [
            Document(
                page_content=r.message.pop("content"),
                metadata={"score": r.dist, **r.message},
            )
            for r in results
            if r.message
        ]
)
            for r in results
            if r.message
        ]
[docs]    def get_relevant_documents(self, query: str) -> List[Document]:
        from zep_python import SearchPayload
        payload: SearchPayload = SearchPayload(text=query)
        results: List[SearchResult] = self.zep_client.search_memory(
            self.session_id, payload, limit=self.top_k
        )
        return self._search_result_to_doc(results)
[docs]    async def aget_relevant_documents(self, query: str) -> List[Document]:
        from zep_python import SearchPayload
        payload: SearchPayload = SearchPayload(text=query)
        results: List[SearchResult] = await self.zep_client.asearch_memory(
            self.session_id, payload, limit=self.top_k
        )
        return self._search_result_to_doc(results)
By Harrison Chase
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
return list(compressed_docs)
By Harrison Chase
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,
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
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")
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