mirror of
https://github.com/hwchase17/langchain
synced 2024-10-29 17:07:25 +00:00
8b8d2a6535
updated unit test with a test for score threshold Updated demo notebook
426 lines
14 KiB
Plaintext
426 lines
14 KiB
Plaintext
{
|
||
"cells": [
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "683953b3",
|
||
"metadata": {},
|
||
"source": [
|
||
"# Vectara\n",
|
||
"\n",
|
||
">[Vectara](https://vectara.com/) is a API platform for building GenAI applications. It provides an easy-to-use API for document indexing and querying that is managed by Vectara and is optimized for performance and accuracy. \n",
|
||
"See the [Vectara API documentation ](https://docs.vectara.com/docs/) for more information on how to use the API.\n",
|
||
"\n",
|
||
"This notebook shows how to use functionality related to the `Vectara`'s integration with langchain.\n",
|
||
"Note that unlike many other integrations in this category, Vectara provides an end-to-end managed service for [Grounded Generation](https://vectara.com/grounded-generation/) (aka retrieval agumented generation), which includes:\n",
|
||
"1. A way to extract text from document files and chunk them into sentences.\n",
|
||
"2. Its own embeddings model and vector store - each text segment is encoded into a vector embedding and stored in the Vectara internal vector store\n",
|
||
"3. A query service that automatically encodes the query into embedding, and retrieves the most relevant text segments (including support for [Hybrid Search](https://docs.vectara.com/docs/api-reference/search-apis/lexical-matching))\n",
|
||
"\n",
|
||
"All of these are supported in this LangChain integration."
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "dc0f4344",
|
||
"metadata": {},
|
||
"source": [
|
||
"# Setup\n",
|
||
"\n",
|
||
"You will need a Vectara account to use Vectara with LangChain. To get started, use the following steps:\n",
|
||
"1. [Sign up](https://console.vectara.com/signup) for a Vectara account if you don't already have one. Once you have completed your sign up you will have a Vectara customer ID. You can find your customer ID by clicking on your name, on the top-right of the Vectara console window.\n",
|
||
"2. Within your account you can create one or more corpora. Each corpus represents an area that stores text data upon ingest from input documents. To create a corpus, use the **\"Create Corpus\"** button. You then provide a name to your corpus as well as a description. Optionally you can define filtering attributes and apply some advanced options. If you click on your created corpus, you can see its name and corpus ID right on the top.\n",
|
||
"3. Next you'll need to create API keys to access the corpus. Click on the **\"Authorization\"** tab in the corpus view and then the **\"Create API Key\"** button. Give your key a name, and choose whether you want query only or query+index for your key. Click \"Create\" and you now have an active API key. Keep this key confidential. \n",
|
||
"\n",
|
||
"To use LangChain with Vectara, you'll need to have these three values: customer ID, corpus ID and api_key.\n",
|
||
"You can provide those to LangChain in two ways:\n",
|
||
"\n",
|
||
"1. Include in your environment these three variables: `VECTARA_CUSTOMER_ID`, `VECTARA_CORPUS_ID` and `VECTARA_API_KEY`.\n",
|
||
"\n",
|
||
"> For example, you can set these variables using os.environ and getpass as follows:\n",
|
||
"\n",
|
||
"```python\n",
|
||
"import os\n",
|
||
"import getpass\n",
|
||
"\n",
|
||
"os.environ[\"VECTARA_CUSTOMER_ID\"] = getpass.getpass(\"Vectara Customer ID:\")\n",
|
||
"os.environ[\"VECTARA_CORPUS_ID\"] = getpass.getpass(\"Vectara Corpus ID:\")\n",
|
||
"os.environ[\"VECTARA_API_KEY\"] = getpass.getpass(\"Vectara API Key:\")\n",
|
||
"```\n",
|
||
"\n",
|
||
"2. Add them to the Vectara vectorstore constructor:\n",
|
||
"\n",
|
||
"```python\n",
|
||
"vectorstore = Vectara(\n",
|
||
" vectara_customer_id=vectara_customer_id,\n",
|
||
" vectara_corpus_id=vectara_corpus_id,\n",
|
||
" vectara_api_key=vectara_api_key\n",
|
||
" )\n",
|
||
"```"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "eeead681",
|
||
"metadata": {},
|
||
"source": [
|
||
"## Connecting to Vectara from LangChain\n",
|
||
"\n",
|
||
"To get started, let's ingest the documents using the from_documents() method.\n",
|
||
"We assume here that you've added your VECTARA_CUSTOMER_ID, VECTARA_CORPUS_ID and query+indexing VECTARA_API_KEY as environment variables."
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 1,
|
||
"id": "04a1f1a0",
|
||
"metadata": {},
|
||
"outputs": [],
|
||
"source": [
|
||
"from langchain.embeddings import FakeEmbeddings\n",
|
||
"from langchain.text_splitter import CharacterTextSplitter\n",
|
||
"from langchain.vectorstores import Vectara\n",
|
||
"from langchain.document_loaders import TextLoader"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 2,
|
||
"id": "be0a4973",
|
||
"metadata": {},
|
||
"outputs": [],
|
||
"source": [
|
||
"loader = TextLoader(\"../../modules/state_of_the_union.txt\")\n",
|
||
"documents = loader.load()\n",
|
||
"text_splitter = CharacterTextSplitter(chunk_size=1000, chunk_overlap=0)\n",
|
||
"docs = text_splitter.split_documents(documents)"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 3,
|
||
"id": "8429667e",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:22.525091Z",
|
||
"start_time": "2023-04-04T10:51:22.522015Z"
|
||
},
|
||
"tags": []
|
||
},
|
||
"outputs": [],
|
||
"source": [
|
||
"vectara = Vectara.from_documents(\n",
|
||
" docs,\n",
|
||
" embedding=FakeEmbeddings(size=768),\n",
|
||
" doc_metadata={\"speech\": \"state-of-the-union\"},\n",
|
||
")"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "90dbf3e7",
|
||
"metadata": {},
|
||
"source": [
|
||
"Vectara's indexing API provides a file upload API where the file is handled directly by Vectara - pre-processed, chunked optimally and added to the Vectara vector store.\n",
|
||
"To use this, we added the add_files() method (as well as from_files()). \n",
|
||
"\n",
|
||
"Let's see this in action. We pick two PDF documents to upload: \n",
|
||
"1. The \"I have a dream\" speech by Dr. King\n",
|
||
"2. Churchill's \"We Shall Fight on the Beaches\" speech"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 4,
|
||
"id": "85ef3468",
|
||
"metadata": {},
|
||
"outputs": [],
|
||
"source": [
|
||
"import tempfile\n",
|
||
"import urllib.request\n",
|
||
"\n",
|
||
"urls = [\n",
|
||
" [\n",
|
||
" \"https://www.gilderlehrman.org/sites/default/files/inline-pdfs/king.dreamspeech.excerpts.pdf\",\n",
|
||
" \"I-have-a-dream\",\n",
|
||
" ],\n",
|
||
" [\n",
|
||
" \"https://www.parkwayschools.net/cms/lib/MO01931486/Centricity/Domain/1578/Churchill_Beaches_Speech.pdf\",\n",
|
||
" \"we shall fight on the beaches\",\n",
|
||
" ],\n",
|
||
"]\n",
|
||
"files_list = []\n",
|
||
"for url, _ in urls:\n",
|
||
" name = tempfile.NamedTemporaryFile().name\n",
|
||
" urllib.request.urlretrieve(url, name)\n",
|
||
" files_list.append(name)\n",
|
||
"\n",
|
||
"docsearch: Vectara = Vectara.from_files(\n",
|
||
" files=files_list,\n",
|
||
" embedding=FakeEmbeddings(size=768),\n",
|
||
" metadatas=[{\"url\": url, \"speech\": title} for url, title in urls],\n",
|
||
")"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "1f9215c8",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T09:27:29.920258Z",
|
||
"start_time": "2023-04-04T09:27:29.913714Z"
|
||
}
|
||
},
|
||
"source": [
|
||
"## Similarity search\n",
|
||
"\n",
|
||
"The simplest scenario for using Vectara is to perform a similarity search. "
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 5,
|
||
"id": "a8c513ab",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:25.204469Z",
|
||
"start_time": "2023-04-04T10:51:24.855618Z"
|
||
},
|
||
"tags": []
|
||
},
|
||
"outputs": [],
|
||
"source": [
|
||
"query = \"What did the president say about Ketanji Brown Jackson\"\n",
|
||
"found_docs = vectara.similarity_search(\n",
|
||
" query, n_sentence_context=0, filter=\"doc.speech = 'state-of-the-union'\"\n",
|
||
")"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 6,
|
||
"id": "fc516993",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:25.220984Z",
|
||
"start_time": "2023-04-04T10:51:25.213943Z"
|
||
},
|
||
"tags": []
|
||
},
|
||
"outputs": [
|
||
{
|
||
"name": "stdout",
|
||
"output_type": "stream",
|
||
"text": [
|
||
"And I did that 4 days ago, when I nominated Circuit Court of Appeals Judge Ketanji Brown Jackson.\n"
|
||
]
|
||
}
|
||
],
|
||
"source": [
|
||
"print(found_docs[0].page_content)"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "1bda9bf5",
|
||
"metadata": {},
|
||
"source": [
|
||
"## Similarity search with score\n",
|
||
"\n",
|
||
"Sometimes we might want to perform the search, but also obtain a relevancy score to know how good is a particular result."
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 7,
|
||
"id": "8804a21d",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:25.631585Z",
|
||
"start_time": "2023-04-04T10:51:25.227384Z"
|
||
}
|
||
},
|
||
"outputs": [],
|
||
"source": [
|
||
"query = \"What did the president say about Ketanji Brown Jackson\"\n",
|
||
"found_docs = vectara.similarity_search_with_score(\n",
|
||
" query, filter=\"doc.speech = 'state-of-the-union'\", score_threshold=0.2,\n",
|
||
")"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 8,
|
||
"id": "756a6887",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:25.642282Z",
|
||
"start_time": "2023-04-04T10:51:25.635947Z"
|
||
}
|
||
},
|
||
"outputs": [
|
||
{
|
||
"name": "stdout",
|
||
"output_type": "stream",
|
||
"text": [
|
||
"Justice Breyer, thank you for your service. One of the most serious constitutional responsibilities a President has is nominating someone to serve on the United States Supreme Court. And I did that 4 days ago, when I nominated Circuit Court of Appeals Judge Ketanji Brown Jackson. One of our nation’s top legal minds, who will continue Justice Breyer’s legacy of excellence. A former top litigator in private practice.\n",
|
||
"\n",
|
||
"Score: 0.786569\n"
|
||
]
|
||
}
|
||
],
|
||
"source": [
|
||
"document, score = found_docs[0]\n",
|
||
"print(document.page_content)\n",
|
||
"print(f\"\\nScore: {score}\")"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "1f9876a8",
|
||
"metadata": {},
|
||
"source": [
|
||
"Now let's do similar search for content in the files we uploaded"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 9,
|
||
"id": "47784de5",
|
||
"metadata": {},
|
||
"outputs": [
|
||
{
|
||
"name": "stdout",
|
||
"output_type": "stream",
|
||
"text": [
|
||
"With this threshold of 1.2 we have 0 documents\n"
|
||
]
|
||
}
|
||
],
|
||
"source": [
|
||
"query = \"We must forever conduct our struggle\"\n",
|
||
"min_score = 1.2\n",
|
||
"found_docs = vectara.similarity_search_with_score(\n",
|
||
" query, filter=\"doc.speech = 'I-have-a-dream'\", score_threshold=min_score,\n",
|
||
")\n",
|
||
"print(f\"With this threshold of {min_score} we have {len(found_docs)} documents\")"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 10,
|
||
"id": "3e22949f",
|
||
"metadata": {},
|
||
"outputs": [
|
||
{
|
||
"name": "stdout",
|
||
"output_type": "stream",
|
||
"text": [
|
||
"With this threshold of 0.2 we have 3 documents\n"
|
||
]
|
||
}
|
||
],
|
||
"source": [
|
||
"query = \"We must forever conduct our struggle\"\n",
|
||
"min_score = 0.2\n",
|
||
"found_docs = vectara.similarity_search_with_score(\n",
|
||
" query, filter=\"doc.speech = 'I-have-a-dream'\", score_threshold=min_score,\n",
|
||
")\n",
|
||
"print(f\"With this threshold of {min_score} we have {len(found_docs)} documents\")\n"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "markdown",
|
||
"id": "691a82d6",
|
||
"metadata": {},
|
||
"source": [
|
||
"## Vectara as a Retriever\n",
|
||
"\n",
|
||
"Vectara, as all the other LangChain vectorstores, is most often used as a LangChain Retriever:"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 11,
|
||
"id": "9427195f",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:26.031451Z",
|
||
"start_time": "2023-04-04T10:51:26.018763Z"
|
||
}
|
||
},
|
||
"outputs": [
|
||
{
|
||
"data": {
|
||
"text/plain": [
|
||
"VectaraRetriever(tags=['Vectara'], metadata=None, vectorstore=<langchain.vectorstores.vectara.Vectara object at 0x1586bd330>, search_type='similarity', search_kwargs={'lambda_val': 0.025, 'k': 5, 'filter': '', 'n_sentence_context': '2'})"
|
||
]
|
||
},
|
||
"execution_count": 11,
|
||
"metadata": {},
|
||
"output_type": "execute_result"
|
||
}
|
||
],
|
||
"source": [
|
||
"retriever = vectara.as_retriever()\n",
|
||
"retriever"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": 12,
|
||
"id": "f3c70c31",
|
||
"metadata": {
|
||
"ExecuteTime": {
|
||
"end_time": "2023-04-04T10:51:26.495652Z",
|
||
"start_time": "2023-04-04T10:51:26.046407Z"
|
||
}
|
||
},
|
||
"outputs": [
|
||
{
|
||
"data": {
|
||
"text/plain": [
|
||
"Document(page_content='Justice Breyer, thank you for your service. One of the most serious constitutional responsibilities a President has is nominating someone to serve on the United States Supreme Court. And I did that 4 days ago, when I nominated Circuit Court of Appeals Judge Ketanji Brown Jackson. One of our nation’s top legal minds, who will continue Justice Breyer’s legacy of excellence. A former top litigator in private practice.', metadata={'source': 'langchain', 'lang': 'eng', 'offset': '596', 'len': '97', 'speech': 'state-of-the-union'})"
|
||
]
|
||
},
|
||
"execution_count": 12,
|
||
"metadata": {},
|
||
"output_type": "execute_result"
|
||
}
|
||
],
|
||
"source": [
|
||
"query = \"What did the president say about Ketanji Brown Jackson\"\n",
|
||
"retriever.get_relevant_documents(query)[0]"
|
||
]
|
||
},
|
||
{
|
||
"cell_type": "code",
|
||
"execution_count": null,
|
||
"id": "2300e785",
|
||
"metadata": {},
|
||
"outputs": [],
|
||
"source": []
|
||
}
|
||
],
|
||
"metadata": {
|
||
"kernelspec": {
|
||
"display_name": "Python 3 (ipykernel)",
|
||
"language": "python",
|
||
"name": "python3"
|
||
},
|
||
"language_info": {
|
||
"codemirror_mode": {
|
||
"name": "ipython",
|
||
"version": 3
|
||
},
|
||
"file_extension": ".py",
|
||
"mimetype": "text/x-python",
|
||
"name": "python",
|
||
"nbconvert_exporter": "python",
|
||
"pygments_lexer": "ipython3",
|
||
"version": "3.10.9"
|
||
}
|
||
},
|
||
"nbformat": 4,
|
||
"nbformat_minor": 5
|
||
}
|