Modern Mini Bank Application

A complete banking system built with PHP 8.3+ (OOP) and modern frontend technologies.

🌟 Features

User Features

• User registration and secure login
• Auto-generated 10-digit account numbers
• Request deposits/withdrawals (admin approval required)
• Instant money transfers between accounts
• Real-time transaction history
• Notification system with badges
• Rate limiting (5 failed login attempts, 15-minute lockout)

Admin Features

• Secure admin panel
• Dashboard with system statistics
• Approve/reject deposit and withdrawal requests
• View all users and their balances
• Monitor all system transactions
• Change admin password

Technical Features

• PHP 8.3+ with strict types
• Full OOP architecture (7 classes)
• Enums for type safety (TransactionType, RequestStatus, UserRole)
• Password hashing with bcrypt
• Login rate limiting and account lockout
• JSON file-based database (no MySQL required)
• RESTful API design
• Responsive design (mobile-friendly)
• Session management

📁 Project Structure

mini-bank/
├── index.html          # User login/register page
├── dashboard.html      # User dashboard
├── admin.html         # Admin control panel
├── config.php         # Configuration & enums
├── Database.php       # Database operations class
├── User.php           # User management class
├── Account.php        # Account operations class
├── Transaction.php    # Transaction handling class
├── Notification.php   # Notification system class
├── Admin.php          # Admin operations class
├── api.php            # API router
├── data.json          # JSON database (not tracked)
└── README.md          # This file

🚀 Installation

Prerequisites

• PHP 8.3 or higher
• Apache web server
• XAMPP/LAMPP (recommended)

Setup Steps

1. Clone the repository:

   git clone https://github.com/AlphaDevelopmental/mini-bank.git
   cd mini-bank

2. Create data.json file:

   cp data.json.example data.json

3. Set permissions (Linux/Mac):

   chmod 666 data.json

4. Start Apache:

   • XAMPP: Open XAMPP Control Panel → Start Apache
   • LAMPP: sudo /opt/lampp/lampp start

5. Access the application:

   • User Portal: http://localhost/mini-bank/
   • Admin Panel: http://localhost/mini-bank/admin.html

🔐 Default Credentials

Admin Login:

• Email: admin@bank.com
• Password: admin123

⚠️ Important: Change the default admin password immediately after first login via Admin Panel → Settings.

📖 Usage

For Users:

1. Register a new account
2. Login with your credentials
3. Note your auto-generated account number
4. Request deposits/withdrawals (requires admin approval)
5. Transfer money instantly to other account numbers
6. View transaction history and notifications

For Admin:

1. Login to admin panel
2. View pending deposit/withdrawal requests
3. Approve or reject requests
4. Monitor all users and system transactions
5. Change admin password in Settings tab

🔒 Security Features

• Bcrypt password hashing
• Rate limiting (5 attempts, 15-min lockout)
• Session management
• Input validation
• CSRF protection ready
• XSS prevention

🛠️ Configuration

Edit config.php to customize:

• Database file location
• Error reporting
• CORS headers
• Session settings

Edit User.php constants to adjust rate limiting:

private const MAX_LOGIN_ATTEMPTS = 5;      // Change attempts limit
private const LOCKOUT_DURATION = 900;      // Change lockout time (seconds)

📝 API Endpoints

• POST /api.php?action=register - User registration
• POST /api.php?action=login - User/admin login
• GET /api.php?action=getAccount&userId={id} - Get account info
• POST /api.php?action=requestDeposit - Request deposit
• POST /api.php?action=requestWithdrawal - Request withdrawal
• POST /api.php?action=transfer - Transfer money
• GET /api.php?action=getTransactions&userId={id} - Get transactions
• GET /api.php?action=getNotifications&userId={id} - Get notifications
• POST /api.php?action=adminApproveRequest - Approve request (admin)
• POST /api.php?action=adminRejectRequest - Reject request (admin)
• POST /api.php?action=adminChangePassword - Change admin password

🧪 Testing

Test Rate Limiting:

1. Try to login with wrong password 5 times
2. Account should lock for 15 minutes
3. Check error logs for debug info

Test Admin Workflow:

1. Register as user
2. Request $1000 deposit
3. Login as admin
4. Approve the deposit request
5. User balance should update instantly

🐛 Troubleshooting

"Undefined array key" errors:

• Run the application once; User.php auto-migrates old data

Can't login to admin:

• Check data.json has admin user with correct password hash
• Verify role is set to "admin"
• Check browser console for errors

Redirect loop on admin page:

• Clear localStorage: localStorage.clear()
• Clear browser cache
• Check admin.html access check logic

File permission errors:

• Linux/Mac: chmod 666 data.json
• Windows: Ensure write permissions

📚 Technologies Used

• Backend: PHP 8.3+ (OOP, Enums, Strict Types)
• Frontend: HTML5, JavaScript (ES6+), Tailwind CSS
• Database: JSON file storage
• Architecture: RESTful API, MVC-inspired

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

📄 License

This project is open source and available under the MIT License.

⚠️ Disclaimer

This is a demonstration project for educational purposes. For production use:

• Use a proper database (MySQL, PostgreSQL)
• Implement additional security measures
• Add SSL/TLS encryption
• Use environment variables for sensitive data
• Implement proper logging and monitoring
• Add comprehensive testing

🔮 Future Enhancements

• MySQL/PostgreSQL database support
• Email notifications (PHPMailer)
• Two-factor authentication (2FA)
• Account statements (PDF generation)
• Loan management system
• Multi-currency support
• Transaction search and filters
• Export to Excel/CSV
• Dark mode
• Mobile app (React Native)

👤 Author

Ajani Taiwo MIcheal

• GitHub: @AlphaDevelopmental

🙏 Acknowledgments

• Tailwind CSS for styling
• PHP community for best practices
• Claude AI for development assistance