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PDF-based QA Bot with Langchain and OpenAI

This project demonstrates a PDF-based Question Answering (QA) bot built using Node.js, Express, Langchain, and OpenAI's GPT-3.5-turbo-instruct model. The bot reads a PDF document, processes its content, and answers questions based on the document's content.

Table of Contents

• Prerequisites
• Installation
• Usage
• API Endpoints
• Environment Variables
• Project Structure
• Contributing
• License

Prerequisites

Ensure you have the following installed:

• Node.js v14.x or higher
• npm v6.x or higher

Installation

1. Clone the repository:

   git clone https://github.com/your-username/your-repo-name.git
   cd your-repo-name

2. Install the dependencies:

   npm install

3. Create a .env file in the root of the project and add your OpenAI API key:

   OPENAI_API_KEY=your_openai_api_key_here
   

Usage

1. Start the server:

   npm start

2. The server will run on port 3000 by default. You can test the bot by sending a POST request to http://localhost:3000/bot with a JSON payload containing your question.

API Endpoints

POST /bot

Endpoint to ask a question based on the content of the PDF document.

Request Body

{
  "question": "Your question here"
}

Response

{
  "answer": "The answer to your question"
}

Environment Variables

The project requires the following environment variables:

• OPENAI_API_KEY: Your OpenAI API key.

Project Structure

.
├── src
│   └── documents
│       └── budget_speech.pdf
├── .env
├── .gitignore
├── package.json
├── README.md
└── server.js

• src/documents/budget_speech.pdf: The PDF document used for the QA bot.
• .env: File to store environment variables.
• server.js: The main server file containing the bot logic.

Contributing

Contributions are welcome! Please open an issue or submit a pull request for any improvements or bug fixes.

1. Fork the repository.
2. Create a new branch (git checkout -b feature-branch).
3. Make your changes and commit them (git commit -m 'Add some feature').
4. Push to the branch (git push origin feature-branch).
5. Open a pull request.

License

This project is licensed under the MIT License - see the LICENSE file for details.

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Feel free to modify this README as per your project's requirements.