Pink Programming Chatbot (Flask + Neo4j)

Overview

• Flask web app scaffold for a chatbot that stores users, chats, and messages in Neo4j.
• Participants complete the Cypher TODOs in db.py to enable user auth, chat creation, and viewing history.
• OpenAI is used to generate assistant replies; reads config from environment variables.

Quick Start with Codespaces

• Create an account on https://console-preview.neo4j.io/ and create a free Aura instance (make sure to save the password).
• In the GitHub repository click the green "Use this template" button and open the project in a codespace.
• Copy .env.example to .env and set values.
  • NEO4J_CONNECTION_URI: Inspect your Aura instance and copy the connection URI.
  • NEO4J_PASSWORD: (paste password that you got during the instance creation).
• Open the Run and Debug menu and start the "Flask: run app.py" configuration.
• It opens a terminal and starts the Flask development server, click on the link to open the app in a new browser tab.
• Try registering a new user, you should see Cypher Error page which means you're ready to start the exercises!

Workshop Tasks (Cypher TODOs in db.py)

• Create/Login User
  • create_user(username, password_hash): create a :User with properties and return it.
  • fetch_user_by_username(username): find a :User by username and return it.
• Chat With Chatbot
  • create_chat_and_first_message(user_id, message): create a :Chat and the first user :Message.
  • create_message(chat_id, role, content): append messages (both user and assistant) to a chat.
• See Previous Chats
  • list_user_chats(user_id): gat all chats for the user, return summary list.
  • fetch_chat(chat_id): return full chat with messages ordered by time.

Pages

• /register and /login: basic authentication using Flask sessions.
• /chat/new: start a new chat by sending the first message.
• /chats: list previous chats.
• /chats/<chat_id>: view and continue a chat.