A Document-based QA Chatbot with LangChain, Chroma and NestJS

Getting Started

Prerequisites

• Node.js >= 18
• OpenAI API Key
• Chroma DB

  Running Chroma DB in Docker

Installing

1. Clone the repository

git clone https://github.com/sivanzheng/chat-bot.git

2. Navigate to the project directory and install the dependencies

cd chat-bot
npm install

3. Create a .env file in the project directory and add the following lines:

OPENAI_API_KEY=your-api-key-here
PROXY_PATH=proxy-path-for-openai
CHROMA_DB_PATH=chroma-db-path
ENABLE_PROXY=is-proxy-enabled

4. Build the project

npm run build

5. Start the server

npm run start

Usage

• Upload a document to the bot

curl --location --request POST 'http://localhost:3000/file/upload' \
--form 'file=@"xxxx.pdf"'

• Parse the document

curl --location --request POST 'http://localhost:3000/document/parse' \
--header 'Content-Type: application/json' \
--data-raw '{
    "fileId": "xxxxxxxxxx",
    "collectionName": "test-docs"
}'

Stream the bot's response you should create an EventSource, like the following example:

const source = new EventSource('http://localhost:3000/dialog?topic={test-docs}&question={question}&history={[history]}')

source.onmessage = function(event) {
  console.log('Received event:', event.data)
}

Here is a client example

License

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