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README.md

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+---
+title: 'Chroma Q&A with Sources Element'
+tags: ['chroma', 'chainlit', 'qa']
+---
+
+# Chroma Q&A with Sources Element
+
+This repository contains a Chainlit application that provides a question-answering service using documents stored in a Chroma vector store. It allows users to upload PDF documents, which are then chunked, embedded, and indexed for efficient retrieval. When a user asks a question, the application retrieves relevant document chunks and uses OpenAI's language model to generate an answer, citing the sources it used.
+
+## High-Level Description
+
+The `app.py` script performs the following functions:
+
+1. **PDF Processing (`process_pdfs`)**: Chunks PDF files into smaller text segments, creates embeddings for each chunk, and stores them in Chroma.
+2. **Document Indexing (`index`)**: Uses `SQLRecordManager` to track document writes into the vector store.
+3. **Question Answering (`on_message`)**: When a user asks a question, the application retrieves relevant document chunks and generates an answer using OpenAI's language model, providing the sources for transparency.
+
+## Quickstart
+
+### Prerequisites
+
+- Python 3.11 or higher
+- Chainlit installed
+- PDF documents to be indexed
+
+### Setup and Run
+
+1. **Install Dependencies:**
+
+Install the required Python packages specified in `requirements.txt`.
+
+```shell
+pip install -r requirements.txt
+```
+
+2. **Process PDFs:**
+
+Place your PDF documents in the `./pdfs` directory.
+
+3. **Run the Application:**
+
+Use the provided `Dockerfile` to build and run the application.
+
+```shell
+docker build -t chroma-qa-chat .
+docker run -p 7860:7860 chroma-qa-chat
+```
+
+   Access the application at `http://localhost:7860`.
+
+## Code Definitions
+
+- `process_pdfs`: Function that processes PDF files and indexes them into Chroma.
+- `on_chat_start`: Event handler that sets up the Chainlit session with the necessary components for question answering.
+- `on_message`: Event handler that processes user messages, retrieves relevant information, and sends back an answer.
+- `PostMessageHandler`: Callback handler that posts the sources of the retrieved documents as a Chainlit element.
+
+![Screenshot](./screenshot.png)
+
+## See Also
+
+For a visual guide on how to use this application, watch the video by [Chris Alexiuk](https://www.youtube.com/watch?v=9SBUStfCtmk&ab_channel=ChrisAlexiuk).
+