Part 28: Building a Chat with PDF App: A Comprehensive Guide

Extras: Connecting Flowise and LangFlow to External App Builders and UIs

Extras: Connecting Flowise and LangFlow to External App Builders and UIs

In today's digital world, the ability to interact with documents dynamically can significantly enhance user experience and productivity. One popular approach is to create a chat application that allows users to upload, search, and interact with PDF documents. This blog post will guide you through the process of building a chat with PDF app using Lang Chain, a powerful open-source library, and integrating it with no-code platforms like Flowwise and Bubble.

Understanding Lang Chain and Document Q&A Systems

Lang Chain simplifies the creation of search applications for PDFs and other documents by providing a framework to build document Q&A systems. These systems typically consist of two main components:

1. Document Ingestion: This involves extracting text from documents, chunking it into smaller pieces, and converting these chunks into vectors stored in a vector database like Pinecone.

2. Search and Retrieval: When a user asks a question, the system converts the query into vectors, compares them to stored vectors, and retrieves relevant information.

Using Flowwise, a no-code platform, we can simplify the process of setting up Lang Chain by dragging and dropping elements on a canvas. Bubble will serve as the user interface, connecting with Flowwise to create a seamless user experience.

Building the Chat Application

Step 1: Setting Up Document Ingestion

1. Flow Configuration: Start by configuring the document ingestion flow in Flowwise. Use a PDF loader to handle PDF documents and set up the necessary API keys for OpenAI and Pinecone.

2. Text Chunking and Embedding: Configure the flow to chunk the document text and convert these chunks into embeddings. Store these embeddings in Pinecone for efficient retrieval.

3. Testing: Upload a test PDF, such as the U.S. Constitution, to ensure the flow works correctly. Verify that the embeddings are stored in Pinecone under the appropriate namespace.

Step 2: Setting Up Search and Retrieval

1. Search Flow: Duplicate the ingestion flow and modify it to create a search flow. Replace the upsert block with a load index block to retrieve stored embeddings.

2. API Configuration: Ensure the API keys and namespaces match those used in the ingestion flow. Test the search functionality to confirm it retrieves the correct information.

Step 3: Integrating with Bubble

1. Embed Chat Widget: Use the embed feature from Flowwise to add a chat widget to your Bubble app. This widget allows users to interact with the document without needing to upload or modify it.

2. Dynamic Upload and Search: For more complex scenarios, configure Bubble to dynamically upload documents to Flowwise and Pinecone. Use metadata filters and namespaces to manage document access and retrieval.

Scenarios for Chat Applications

Scenario 1: Simple Chat Widget

For websites that only require a search widget, embed the Flowwise chat widget directly into your site. Users can search through existing documentation without uploading new files.

Scenario 2: Organizational Document Search

When multiple users need access to a shared document repository, use a common namespace in Pinecone. This allows all users to search the organization's documents without separating uploads by user.

Scenario 3: Individual User Document Management

For applications where each user's documents must be kept separate, assign a unique namespace for each user. Use metadata filters to allow users to search within specific documents or across their entire namespace.

Conclusion

Creating a chat with PDF app using Lang Chain, Flowwise, and Bubble offers a powerful solution for dynamic document interaction. Whether you need a simple search widget or a complex system with multiple users and document partitions, these tools provide the flexibility and functionality to meet your needs. By following this guide, you can build a robust chat application that enhances user engagement and productivity. Explore additional features like chat history and document management to further expand your application's capabilities.