✅ SmartTodo — Task Manager with Authentication

A clean, beginner-friendly full-stack to-do list web app built with Python (Flask). SmartTodo lets users create an account, log in, and manage their own personal task list — all without needing a database. User accounts and tasks are stored in simple JSON files.

This project is intentionally kept simple and well-commented, making it a great starting point for anyone learning Flask, sessions/cookies, or basic full-stack web development.

---

✨ Features

• 🔐 User registration — create an account with a username and password
• 🔑 User login — secure password checking with hashed passwords (werkzeug.security)
• 🍪 Session-based authentication — Flask sessions/cookies keep users logged in
• 🚪 Logout system — clears the session and redirects to the login page
• 📋 Per-user dashboard — each user only ever sees their own tasks
• ➕ Add tasks
• ✔️ Mark tasks as completed (toggle on/off)
• 🗑️ Delete tasks
• 💾 No database required — everything is stored in plain JSON files
• 🎨 Clean, responsive UI built with hand-written HTML & CSS

---

🗂️ Project Structure

SmartTodo/
│
├── main.py                # Flask application (routes, auth logic, task logic)
├── requirements.txt        # Python dependencies
├── tasks.json               # All users' tasks, keyed by username
├── users.json                # Registered users and hashed passwords
├── README.md
│
├── templates/
│   ├── login.html          # Login page
│   ├── register.html       # Registration page
│   └── index.html          # Main dashboard (task list)
│
└── static/
    └── style.css            # App styling

---

🛠️ Tech Stack

Layer	Technology
Backend	Python 3, Flask
Frontend	HTML5, CSS3 (no frameworks)
Auth	Flask sessions + Werkzeug password hashing
Storage	JSON files (users.json, tasks.json)

---

🚀 Getting Started

1. Clone or download the project

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

2. (Recommended) Create a virtual environment

python -m venv venv

# Activate it:
# Windows:
venv\Scripts\activate
# macOS / Linux:
source venv/bin/activate

3. Install dependencies

pip install -r requirements.txt

4. Run the app

python main.py

5. Open it in your browser

http://127.0.0.1:5000

You'll be redirected to the login page. Click "Create one" to register a new account, then log in and start adding tasks!

---

📦 JSON Data Format

users.json

Stores registered usernames with their hashed passwords (passwords are never stored in plain text).

{
    "jane_doe": {
        "password": "pbkdf2:sha256:600000$abc123...$def456..."
    }
}

tasks.json

Tasks are grouped by username, so every user only sees their own list.

{
    "jane_doe": [
        {
            "id": 1,
            "task": "Buy groceries",
            "completed": false
        },
        {
            "id": 2,
            "task": "Finish Flask project",
            "completed": true
        }
    ]
}

---

🔒 Security Notes

This project is built for learning purposes and keeps things intentionally simple. A few things to be aware of if you plan to deploy it publicly:

• Passwords are hashed with werkzeug.security ✅ (good practice, already included)
• The Flask secret_key in main.py is hardcoded — in production, load it from an environment variable instead.
• JSON files are not ideal for handling many concurrent users — for a production app, consider migrating to a real database (SQLite, PostgreSQL, etc.).
• debug=True should be turned off (debug=False) before deploying.

---

🧭 Possible Improvements

Some ideas if you want to extend this project further:

• Add due dates / priority levels to tasks
• Add task editing (not just add/delete)
• Add a "Remember Me" option using persistent cookies
• Move from JSON storage to SQLite using SQLAlchemy
• Add task categories or tags
• Add unit tests with pytest

---

📄 License

This project is free to use for learning and portfolio purposes.

---

👤 Author

Built as a beginner-friendly Flask portfolio project — feel free to fork it, improve it, and make it your own!