Upload 10 files

Dockerfile

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+FROM python:3.9
+
+RUN useradd -m -u 1000 user
+USER user
+ENV PATH="/home/user/.local/bin:$PATH"
+
+WORKDIR /app
+
+COPY --chown=user ./requirements.txt requirements.txt
+RUN pip install --no-cache-dir --upgrade -r requirements.txt
+
+COPY --chown=user . /app
+CMD ["gunicorn", "app:app", "-b", "0.0.0.0:7860"]

LICENSE

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+MIT License
+
+Copyright (c) 2025 Rahul Bhaskar
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,10 +1,388 @@
 ---
-title: LOGIN
-emoji: 🚀
+title: Flask Login
+emoji: 💻
 colorFrom: green
-colorTo: blue
+colorTo: indigo
 sdk: docker
-pinned: false
+pinned: true
+license: mit
+short_description: A simple yet comprehensive Flask-based user authentication.
 ---
 
 Check out the configuration reference at https://huggingface.co/docs/hub/spaces-config-reference
+
+---
+
+# Flask Login System 🔐
+
+A simple yet comprehensive Flask-based user authentication system with SQLite database integration, featuring user registration, login, session management, and "Remember Me" functionality.
+
+**Live Demo:** [https://rahul23232-flask-login.hf.space/](https://rahul23232-flask-login.hf.space/)
+
+## 📋 Table of Contents
+
+- [Features](#features)
+- [Technologies Used](#technologies-used)
+- [Installation](#installation)
+- [Usage](#usage)
+- [Project Structure](#project-structure)
+- [API Routes](#api-routes)
+- [Database Schema](#database-schema)
+- [Security Considerations](#security-considerations)
+- [Contributing](#contributing)
+- [License](#license)
+
+## ✨ Features
+
+- **User Registration**: Create new user accounts with unique usernames
+- **User Authentication**: Secure login system with credential verification
+- **Session Management**: Server-side session handling for user state
+- **Remember Me**: Optional persistent login that survives browser restarts
+- **Cookie Management**: Last visit tracking with customizable expiration
+- **SQLite Integration**: Lightweight database for user storage
+- **Responsive Design**: Clean, user-friendly interface
+- **Error Handling**: Proper validation and error messages
+
+## 🛠️ Technologies Used
+
+- **Backend**: Python 3.x, Flask
+- **Database**: SQLite3
+- **Frontend**: HTML, CSS (Bootstrap-compatible)
+- **Session Management**: Flask Sessions
+- **Deployment**: Hugging Face Spaces
+
+## 📦 Installation
+
+### Prerequisites
+
+- Python 3.7 or higher
+- pip (Python package installer)
+
+### Local Setup
+
+1. **Clone the repository**
+   ```bash
+   git clone https://github.com/yourusername/flask-login-system.git
+   cd flask-login-system
+   ```
+
+2. **Install dependencies**
+   ```bash
+   pip install flask
+   ```
+
+3. **Run the application**
+   ```bash
+   python app.py
+   ```
+
+4. **Access the application**
+   - Open your browser and navigate to `http://localhost:5000`
+
+### Docker Setup (for Hugging Face Spaces)
+
+The project includes Docker configuration for deployment on Hugging Face Spaces:
+
+```dockerfile
+FROM python:3.9-slim
+
+WORKDIR /app
+
+COPY requirements.txt .
+RUN pip install -r requirements.txt
+
+COPY . .
+
+EXPOSE 7860
+
+CMD ["python", "app.py"]
+```
+
+## 🎯 Usage
+
+### Getting Started
+
+1. **Access the Application**: Navigate to the home URL
+2. **Create Account**: Click "Sign Up" to create a new user account
+3. **Login**: Use your credentials to log in
+4. **Remember Me**: Check the "Remember Me" option to stay logged in
+5. **Logout**: Click "Logout" to end your session
+
+### User Flow
+
+```mermaid
+graph TD
+    A[Visit Homepage] --> B{User Logged In?}
+    B -->|No| C[Redirect to Login]
+    B -->|Yes| D[Show Dashboard]
+    C --> E[Login Form]
+    E --> F[Submit Credentials]
+    F --> G{Valid Credentials?}
+    G -->|No| H[Show Error]
+    G -->|Yes| I[Create Session]
+    I --> J{Remember Me?}
+    J -->|Yes| K[Set Permanent Session]
+    J -->|No| L[Set Temporary Session]
+    K --> D
+    L --> D
+    D --> M[Logout Option]
+    M --> N[Clear Session & Cookies]
+    N --> C
+```
+
+## 📁 Project Structure
+
+```
+flask-login-system/
+├── app.py                 # Main Flask application
+├── templates/            # HTML templates
+│   ├── base.html        # Base template
+│   ├── login.html       # Login page
+│   ├── signup.html      # Registration page
+│   └── home.html        # Dashboard/home page
+├── static/              # Static files (CSS, JS, images)
+│   └── style.css       # Custom styles
+├── users.db            # SQLite database (created automatically)
+├── requirements.txt    # Python dependencies
+├── Dockerfile         # Docker configuration
+├── README.md          # Project documentation
+└── .gitignore         # Git ignore rules
+```
+
+## 🛣️ API Routes
+
+### Public Routes
+
+| Route | Method | Description | Parameters |
+|-------|---------|-------------|------------|
+| `/login` | GET, POST | User login page | `username`, `password`, `remember` |
+| `/signup` | GET, POST | User registration | `username`, `password` |
+
+### Protected Routes
+
+| Route | Method | Description | Authentication Required |
+|-------|---------|-------------|------------------------|
+| `/` | GET | Homepage/Dashboard | Yes |
+| `/logout` | GET | User logout | Yes |
+
+### Route Details
+
+#### `/` (Homepage)
+- **Method**: GET
+- **Authentication**: Required
+- **Description**: Main dashboard showing welcome message and last visit info
+- **Response**: Redirects to login if not authenticated
+
+#### `/signup` (Registration)
+- **Methods**: GET, POST
+- **Parameters**: 
+  - `username` (string): Unique username
+  - `password` (string): User password
+- **Validation**: Username must be unique
+- **Response**: Redirects to login on success
+
+#### `/login` (Authentication)
+- **Methods**: GET, POST
+- **Parameters**:
+  - `username` (string): User's username
+  - `password` (string): User's password  
+  - `remember` (checkbox): Optional "Remember Me"
+- **Response**: Redirects to homepage on success
+
+#### `/logout` (Session Termination)
+- **Method**: GET
+- **Description**: Clears session and cookies
+- **Response**: Redirects to login page
+
+## 🗄️ Database Schema
+
+### Users Table
+
+```sql
+CREATE TABLE users (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    username TEXT UNIQUE NOT NULL,
+    password TEXT NOT NULL
+);
+```
+
+| Column | Type | Constraints | Description |
+|--------|------|-------------|-------------|
+| `id` | INTEGER | PRIMARY KEY, AUTOINCREMENT | Unique user identifier |
+| `username` | TEXT | UNIQUE, NOT NULL | User's login name |
+| `password` | TEXT | NOT NULL | User's password (plain text) |
+
+### Database Operations
+
+- **Connection**: SQLite3 with `sqlite3.Row` factory for dictionary-like access
+- **Initialization**: Automatic table creation on first run
+- **Queries**: Parameterized queries to prevent SQL injection
+
+## 🔒 Security Considerations
+
+### Current Implementation
+
+- ✅ SQL injection protection via parameterized queries
+- ✅ Session-based authentication
+- ✅ CSRF protection through Flask's secret key
+- ✅ Input validation and error handling
+
+### Production Recommendations
+
+- ⚠️ **Password Hashing**: Currently stores plain text passwords
+  ```python
+  from werkzeug.security import generate_password_hash, check_password_hash
+  
+  # For registration
+  hashed_password = generate_password_hash(password)
+  
+  # For login verification
+  check_password_hash(stored_hash, provided_password)
+  ```
+
+- ⚠️ **Environment Variables**: Move secret key to environment variables
+  ```python
+  import os
+  app.secret_key = os.environ.get('SECRET_KEY', 'fallback-secret-key')
+  ```
+
+- ⚠️ **HTTPS**: Enable HTTPS in production
+- ⚠️ **Rate Limiting**: Implement login attempt limits
+- ⚠️ **Input Validation**: Add comprehensive input sanitization
+- ⚠️ **Session Security**: Configure secure session cookies
+
+### Recommended Security Enhancements
+
+```python
+# Enhanced security configuration
+app.config.update(
+    SESSION_COOKIE_SECURE=True,      # HTTPS only
+    SESSION_COOKIE_HTTPONLY=True,    # No JS access
+    SESSION_COOKIE_SAMESITE='Lax',   # CSRF protection
+    PERMANENT_SESSION_LIFETIME=timedelta(hours=1)  # Shorter sessions
+)
+```
+
+## 🎨 Frontend Templates
+
+### Template Structure
+
+All templates extend `base.html` for consistent styling:
+
+```html
+<!-- base.html -->
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>{% block title %}Flask Login System{% endblock %}</title>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" rel="stylesheet">
+</head>
+<body>
+    <div class="container mt-4">
+        {% block content %}{% endblock %}
+    </div>
+</body>
+</html>
+```
+
+### Form Examples
+
+#### Login Form
+```html
+<form method="POST">
+    <div class="mb-3">
+        <label for="username" class="form-label">Username</label>
+        <input type="text" class="form-control" name="username" required>
+    </div>
+    <div class="mb-3">
+        <label for="password" class="form-label">Password</label>
+        <input type="password" class="form-control" name="password" required>
+    </div>
+    <div class="mb-3 form-check">
+        <input type="checkbox" class="form-check-input" name="remember">
+        <label class="form-check-label">Remember Me</label>
+    </div>
+    <button type="submit" class="btn btn-primary">Login</button>
+</form>
+```
+
+## 🚀 Deployment
+
+### Hugging Face Spaces
+
+The project is configured for deployment on Hugging Face Spaces:
+
+1. **Create Space**: Create a new Space on Hugging Face
+2. **Upload Files**: Push your code to the Space repository
+3. **Configuration**: Ensure `app.py` runs on port 7860
+4. **Environment**: The Space will automatically build and deploy
+
+### Local Development
+
+```bash
+# Development mode with auto-reload
+export FLASK_ENV=development
+export FLASK_DEBUG=1
+python app.py
+```
+
+### Production Deployment
+
+```bash
+# Use a production WSGI server
+pip install gunicorn
+gunicorn -w 4 -b 0.0.0.0:5000 app:app
+```
+
+## 🤝 Contributing
+
+1. Fork the repository
+2. Create a feature branch (`git checkout -b feature/amazing-feature`)
+3. Commit your changes (`git commit -m 'Add amazing feature'`)
+4. Push to the branch (`git push origin feature/amazing-feature`)
+5. Open a Pull Request
+
+### Development Guidelines
+
+- Follow PEP 8 style guidelines
+- Add comments for complex logic
+- Update documentation for new features
+- Test all functionality before submitting
+
+## 📝 License
+
+This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.
+
+## 🐛 Known Issues
+
+- Plain text password storage (security concern)
+- No password strength validation
+- No account recovery mechanism
+- Limited input sanitization
+
+## 🔮 Future Enhancements
+
+- [ ] Password hashing with bcrypt/scrypt
+- [ ] Email verification system
+- [ ] Password reset functionality
+- [ ] User profile management
+- [ ] Role-based access control
+- [ ] OAuth integration (Google, GitHub)
+- [ ] Rate limiting and brute force protection
+- [ ] Advanced session management
+- [ ] API endpoints for mobile apps
+- [ ] Unit and integration tests
+
+## 📞 Support
+
+For questions, issues, or contributions:
+
+- **Repository**: [GitHub Repository](https://github.com/yourusername/flask-login-system)
+- **Live Demo**: [Flask Login System](https://rahul23232-flask-login.hf.space/)
+- **Issues**: Use GitHub Issues for bug reports and feature requests
+
+---
+
+**Note**: This is a demonstration project for educational purposes. For production use, implement proper security measures including password hashing, HTTPS, and comprehensive input validation.

app.py

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+
+"""
+Flask Login System with SQLite
+Features:
+- Signup (create new account)
+- Login (check user credentials)
+- Session (to remember login state)
+- Cookies (to store last visit info)
+- "Remember Me" option (stay logged in even after closing browser)
+"""
+
+from flask import Flask, render_template, request, redirect, url_for, session, make_response
+import sqlite3
+from datetime import timedelta
+
+# Flask App Setup
+app = Flask(__name__)
+
+# Secret key is used to sign session data (must be kept secret in real apps!)
+app.secret_key = "supersecretkey"
+
+# Permanent sessions last for 7 days (used when "Remember Me" is checked)
+app.permanent_session_lifetime = timedelta(days=7)
+
+
+# Helper function to connect to SQLite database
+def get_db_connection():
+    # Connect to SQLite database (creates file users.db if it doesn’t exist)
+    conn = sqlite3.connect("users.db")
+    conn.row_factory = sqlite3.Row  # Makes rows behave like dictionaries
+    return conn
+
+
+# Initialize database with a "users" table
+def init_db():
+    conn = get_db_connection()
+    conn.execute("""
+        CREATE TABLE IF NOT EXISTS users (
+            id INTEGER PRIMARY KEY AUTOINCREMENT, -- Auto-increment ID
+            username TEXT UNIQUE NOT NULL,        -- Unique username
+            password TEXT NOT NULL                -- Password (plain text for demo, should use hashing!)
+        )
+    """)
+    conn.commit()
+    conn.close()
+
+# Call database initialization at startup
+init_db()
+
+
+# Home Page (only logged-in users can see this)
+@app.route("/")
+def home():
+    # Check if the user is logged in using session
+    if "username" in session:
+        username = session["username"]  # Get logged-in username from session
+
+        # Get last visit message from cookie (if not found, show default message)
+        last_visit = request.cookies.get("last_visit", "First time visiting!")
+
+        return render_template("home.html", username=username, last_visit=last_visit)
+
+    # If not logged in, redirect to login page
+    return redirect(url_for("login"))
+
+
+# Signup Page
+@app.route("/signup", methods=["GET", "POST"])
+def signup():
+    if request.method == "POST":  # When user submits the form
+        username = request.form["username"]
+        password = request.form["password"]
+
+        conn = get_db_connection()
+        try:
+            # Insert new user into database
+            conn.execute("INSERT INTO users (username, password) VALUES (?, ?)", (username, password))
+            conn.commit()
+            conn.close()
+
+            # After signup, redirect to login page
+            return redirect(url_for("login"))
+
+        except sqlite3.IntegrityError:
+            # This happens if the username already exists
+            return "Username already exists! Try another."
+    
+    # If GET request, show signup form
+    return render_template("signup.html")
+
+
+# Login Page
+@app.route("/login", methods=["GET", "POST"])
+def login():
+    if request.method == "POST":  # When user submits login form
+        username = request.form["username"]
+        password = request.form["password"]
+
+        # Checkbox value: will be "on" if user ticks "Remember Me"
+        remember = request.form.get("remember")
+
+        # Check if username & password exist in database
+        conn = get_db_connection()
+        user = conn.execute("SELECT * FROM users WHERE username=? AND password=?", 
+                            (username, password)).fetchone()
+        conn.close()
+
+        if user:
+            # ✅ User found → start session
+            if remember == "on":
+                # Session will survive browser close (7 days)
+                session.permanent = True
+            else:
+                # Session ends when browser closes
+                session.permanent = False
+
+            # Store username inside session
+            session["username"] = username
+
+            # Create response with cookie
+            resp = make_response(redirect(url_for("home")))
+
+            # Save a cookie with "last visit" info
+            # If "Remember Me" checked → cookie valid for 7 days
+            # Else → cookie lasts only until browser closes
+            resp.set_cookie("last_visit", "Welcome back, " + username, 
+                            max_age=(7*24*60*60 if remember == "on" else None))
+
+            return resp
+        else:
+            # If username or password is wrong
+            return "Invalid username or password. Try again."
+
+    # If GET request, show login form
+    return render_template("login.html")
+
+
+# Logout Page
+@app.route("/logout")
+def logout():
+    # Remove username from session
+    session.pop("username", None)
+
+    # Also delete the "last_visit" cookie
+    resp = make_response(redirect(url_for("login")))
+    resp.set_cookie("last_visit", "", expires=0)
+    return resp
+
+
+# Run the App
+if __name__ == "__main__":
+    app.run(debug=True, host="0.0.0.0", port=5000)

requirements.txt

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+flask
+gunicorn
+requests
+datetime

templates/home.html

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+<!DOCTYPE html>
+<html>
+<head>
+    <title>Home</title>
+</head>
+<body>
+    <h2>Welcome, {{ username }}!</h2>
+    <p>Last visit info (from cookie): {{ last_visit }}</p>
+    <a href="{{ url_for('logout') }}">Logout</a>
+</body>
+</html>

templates/login.html

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+<!DOCTYPE html>
+<html>
+<head>
+    <title>Login</title>
+</head>
+<body>
+    <h2>Login</h2>
+    <form method="POST">
+        <label>Username:</label>
+        <input type="text" name="username" required><br><br>
+
+        <label>Password:</label>
+        <input type="password" name="password" required><br><br>
+
+        <label>
+            <input type="checkbox" name="remember"> Remember Me
+        </label><br><br>
+
+        <button type="submit">Login</button>
+    </form>
+    <p>Don't have an account? <a href="{{ url_for('signup') }}">Signup here</a></p>
+</body>
+</html>

templates/signup.html

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+<!DOCTYPE html>
+<html>
+<head>
+    <title>Signup</title>
+</head>
+<body>
+    <h2>Signup</h2>
+    <form method="POST">
+        <label>Username:</label>
+        <input type="text" name="username" required><br><br>
+
+        <label>Password:</label>
+        <input type="password" name="password" required><br><br>
+
+        <button type="submit">Signup</button>
+    </form>
+    <p>Already have an account? <a href="{{ url_for('login') }}">Login here</a></p>
+</body>
+</html>