Get Started with the Haystack Integration
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You can integrate Atlas Vector Search with Haystack to build custom applications with LLMs and implement retrieval-augmented generation (RAG). This tutorial demonstrates how to start using Atlas Vector Search with Haystack to perform semantic search on your data and build a RAG implementation. Specifically, you perform the following actions:
Set up the environment.
Create an Atlas Vector Search index.
Store custom data on Atlas.
Implement RAG by using Atlas Vector Search to answer questions on your data.
Background
Haystack is a framework for building custom applications with LLMs, embedding models, and vector search. By integrating Atlas Vector Search with Haystack, you can use Atlas as a vector database and use Atlas Vector Search to implement RAG by retrieving semantically similar documents from your data. To learn more about RAG, see Retrieval-Augmented Generation (RAG) with Atlas Vector Search.
Prerequisites
To complete this tutorial, you must have the following:
An Atlas cluster running MongoDB version 6.0.11, 7.0.2, or later (including RCs).
An OpenAI API Key. You must have a paid OpenAI account with credits available for API requests.
A notebook to run your Python project such as Colab.
Note
If you're using Colab, ensure that your notebook session's IP address is included in your Atlas project's access list.
Set Up the Environment
You must first set up the environment for this tutorial.
Create an interactive Python notebook by saving a file
with the .ipynb
extension, and then run the
following code snippets in the notebook:
Install and import dependencies.
Run the following command:
pip --quiet install mongodb-atlas-haystack pymongo Run the following code to import the required packages:
import getpass, os from haystack import Pipeline, Document from haystack.document_stores.types import DuplicatePolicy from haystack.components.writers import DocumentWriter from haystack.components.generators import OpenAIGenerator from haystack.components.builders.prompt_builder import PromptBuilder from haystack.components.embedders import OpenAITextEmbedder, OpenAIDocumentEmbedder from haystack_integrations.document_stores.mongodb_atlas import MongoDBAtlasDocumentStore from haystack_integrations.components.retrievers.mongodb_atlas import MongoDBAtlasEmbeddingRetriever from pymongo import MongoClient from pymongo.operations import SearchIndexModel
Define environmental variables.
Run the following code and provide the following when prompted:
Your OpenAI API Key.
Your Atlas cluster's SRV connection string.
os.environ["OPENAI_API_KEY"] = getpass.getpass("OpenAI API Key:") os.environ["MONGO_CONNECTION_STRING"]=getpass.getpass("MongoDB Atlas Connection String:")
Note
Your connection string should use the following format:
mongodb+srv://<db_username>:<db_password>@<clusterName>.<hostname>.mongodb.net
Create the Atlas Vector Search Index
Note
To create an Atlas Vector Search index, you must have Project Data Access Admin
or higher access to the Atlas project.
In this section, you create the haystack_db
database
and test
collection to store your custom data.
Then, to enable vector search queries on your data, you
create an Atlas Vector Search index.
Create the haystack_db.test
collection.
Run the following code to create your haystack_db
database and test
collection.
# Create your database and collection db_name = "haystack_db" collection_name = "test" database = client[db_name] database.create_collection(collection_name) # Define collection collection = client[db_name][collection_name]
Define the Atlas Vector Search index.
Run the following code to create an index of the vectorSearch type. The embedding
field
contains the embeddings that you'll create using OpenAI's
text-embedding-ada-002
embedding model. The index
definition specifies 1536
vector dimensions and
measures similarity using cosine
.
# Create your index model, then create the search index search_index_model = SearchIndexModel( definition={ "fields": [ { "type": "vector", "path": "embedding", "numDimensions": 1536, "similarity": "cosine" } ] }, name="vector_index", type="vectorSearch" ) collection.create_search_index(model=search_index_model)
The index should take about one minute to build. While it builds, the index is in an initial sync state. When it finishes building, you can start querying the data in your collection.
Store Custom Data in Atlas
In this section, you instantiate Atlas as a vector database, also called a document store. Then, you create vector embeddings from custom data and store these documents in a collection in Atlas. Paste and run the following code snippets in your notebook.
Instantiate Atlas as a document store.
Run the following code to instantiate Atlas as a document store. This code establishes a connection to your Atlas cluster and specifies the following:
haystack_db
andtest
as the Atlas database and collection used to store the documents.vector_index
as the index used to run semantic search queries.
document_store = MongoDBAtlasDocumentStore( database_name="haystack_db", collection_name="test", vector_search_index="vector_index", )
Load sample data on your Atlas cluster.
This code defines a few sample documents and runs a pipeline with the following components:
An embedder from OpenAI to convert your document into vector embeddings.
A document writer to populate your document store with the sample documents and their embeddings.
# Create some example documents documents = [ Document(content="My name is Jean and I live in Paris."), Document(content="My name is Mark and I live in Berlin."), Document(content="My name is Giorgio and I live in Rome."), ] # Initializing a document embedder to convert text content into vectorized form. doc_embedder = OpenAIDocumentEmbedder() # Setting up a document writer to handle the insertion of documents into the MongoDB collection. doc_writer = DocumentWriter(document_store=document_store, policy=DuplicatePolicy.SKIP) # Creating a pipeline for indexing documents. The pipeline includes embedding and writing documents. indexing_pipe = Pipeline() indexing_pipe.add_component(instance=doc_embedder, name="doc_embedder") indexing_pipe.add_component(instance=doc_writer, name="doc_writer") # Connecting the components of the pipeline for document flow. indexing_pipe.connect("doc_embedder.documents", "doc_writer.documents") # Running the pipeline with the list of documents to index them in MongoDB. indexing_pipe.run({"doc_embedder": {"documents": documents}})
Calculating embeddings: 100%|██████████| 1/1 [00:00<00:00, 4.16it/s] {'doc_embedder': {'meta': {'model': 'text-embedding-ada-002', 'usage': {'prompt_tokens': 32, 'total_tokens': 32}}}, 'doc_writer': {'documents_written': 3}}
Tip
After running the sample code, you can
view your vector embeddings in the Atlas UI
by navigating to the haystack_db.test
collection in your cluster.
Answer Questions on Your Data
This section demonstrates how to implement RAG in your application with Atlas Vector Search and Haystack.
The following code defines and runs a pipeline with the follow components:
The OpenAITextEmbedder embedder to create embeddings from your query.
The MongoDBAtlasEmbeddingRetriever retriever to retrieve embeddings from your document store that are similar to the query embedding.
A PromptBuilder that passes a prompt template to instruct the LLM to use the retrieved document as context for your prompt.
The OpenAIGenerator generator to generate a context-aware response using an LLM from OpenAI.
In this example, you prompt the LLM with the sample query
Where does Mark live?
. The LLM generates an accurate,
context-aware response from the custom data you stored
in Atlas.
# Template for generating prompts for a movie recommendation engine. prompt_template = """ You are an assistant allowed to use the following context documents.\nDocuments: {% for doc in documents %} {{ doc.content }} {% endfor %} \nQuery: {{query}} \nAnswer: """ # Setting up a retrieval-augmented generation (RAG) pipeline for generating responses. rag_pipeline = Pipeline() rag_pipeline.add_component("text_embedder", OpenAITextEmbedder()) # Adding a component for retrieving related documents from MongoDB based on the query embedding. rag_pipeline.add_component(instance=MongoDBAtlasEmbeddingRetriever(document_store=document_store,top_k=15), name="retriever") # Building prompts based on retrieved documents to be used for generating responses. rag_pipeline.add_component(instance=PromptBuilder(template=prompt_template), name="prompt_builder") # Adding a language model generator to produce the final text output. rag_pipeline.add_component(instance=OpenAIGenerator(), name="llm") # Connecting the components of the RAG pipeline to ensure proper data flow. rag_pipeline.connect("text_embedder.embedding", "retriever.query_embedding") rag_pipeline.connect("retriever", "prompt_builder.documents") rag_pipeline.connect("prompt_builder", "llm") # Run the pipeline query = "Where does Mark live?" result = rag_pipeline.run( { "text_embedder": {"text": query}, "prompt_builder": {"query": query}, }); print(result['llm']['replies'][0])
Mark lives in Berlin.
Next Steps
MongoDB also provides the following developer resources: