Flask+Neo4j

Introduction

The Flask + Neo4j Authentication System is a simple yet effective authentication solution built using Flask and Neo4j. This template is designed to facilitate user registration, login, and session management, making it suitable for small projects or as a foundation for more complex systems.

Features

• User Registration: Allows new users to register with a unique username and password.
• User Login: Authenticates users with their username and password.
• Dashboard: Displays a personalized dashboard after successful login.
• Session Management: Utilizes Flask sessions to manage user login states.
• User Logout: Allows users to log out and clear their session.

Technologies Used

• Flask: A lightweight WSGI web application framework in Python.
• Neo4j: A graph database management system that provides efficient and flexible handling of graph data.
• python-dotenv: Loads environment variables from a .env file.

Installation Steps

To set up the Flask + Neo4j Authentication System with Universal-Box, follow these steps:

1. Create a virtual environment and activate it:
   python3 -m venv venv
   ./venv/Scripts/activate  # Use `venv\Scripts\activate` on Windows
   

2. Install the required dependencies:
   pip install -r requirements.txt
   

3. Set up the environment variables: Create a .env file in the root directory and add the following:
   NEO4J_URI=bolt://localhost:7687
   NEO4J_USER=yourusername
   NEO4J_PASSWORD=yourpassword
   

4. Run the application:
   flask run
   

5. Access the application: Open your browser and navigate to http://127.0.0.1:5000/ to access the login page.

   Routes and Functionalities

   User Registration

   • /register GET, POST:
     • GET: Renders the registration page where new users can sign up.
     • POST: Handles form submissions for user registration. If the username is already taken, it flashes an error message; otherwise, it creates a new user in Neo4j and redirects to the login page with a success message.

   User Login

   • /login GET, POST:
     • GET: Displays the login page where users can log in with their credentials.
     • POST: Handles login form submissions. If credentials are correct, it logs the user in by storing their username in the session and redirects to the dashboard; if incorrect, it flashes an error message.

   Dashboard Access

   • /dashboard GET:
     • Displays the dashboard page if the user is logged in; otherwise redirects to the login page.

   User Logout

   • /logout GET:
     • Logs the user out by clearing their session and redirects them to the homepage.

   Homepage

   • / GET:
     • Renders the main homepage of the application.

Flash Messages

The application uses flash messages to communicate various events to users:

• Registration Success: "Registration successful. Please log in."
• Registration Error: "Username already exists. Please choose a different one."
• Login Error: "Invalid username or password. Please try again."

Database Structure

The application uses Neo4j for storing user information. Neo4j is a graph database that stores data in nodes and relationships. In this application:

• User Nodes: Represented by User nodes in Neo4j.
• Constraints: A uniqueness constraint is created on the username property to ensure unique usernames.

This template was developed using Universal-Box.