Oxygen Cylinder Tracker

A comprehensive industrial gas cylinder management web application built with Flask and PostgreSQL.

• Customer Management: Complete CRUD operations with Access-compatible field structure
• Cylinder Inventory: Advanced tracking with rental status, custom IDs, and bulk operations
• Rental Management: Real-time tracking with duration calculation and history
• Search & Filter: Global search across customers and cylinders with advanced filtering
• Bulk Operations: Multi-cylinder dispatch and return operations
• Data Export: CSV and PDF reports for customers, cylinders, and rental activities

• Role-Based Access: Admin, User, and Viewer roles with different permissions
• Secure Authentication: Werkzeug password hashing and session management
• User Interface: Clean, responsive Bootstrap 5 design with mobile optimization

• PostgreSQL Database: Robust data storage with SQLAlchemy ORM
• Data Import: MS Access database import functionality with field mapping
• Backup System: Automatic data archiving and backup capabilities
• Performance: Optimized queries with pagination for large datasets

• Python 3.11+
• PostgreSQL database
• Render account (for deployment)

1. Clone the repository
2. Set environment variables:
   • DATABASE_URL: PostgreSQL connection string
   • SESSION_SECRET: Secure session key
3. Install dependencies: pip install -r requirements.txt
4. Run: python main.py

1. Push code to GitHub repository
2. Create PostgreSQL database on Render
3. Create web service with configuration from render.yaml
4. Set environment variables in Render dashboard
5. Deploy automatically via GitHub integration

See RENDER_DEPLOYMENT.md for detailed deployment instructions.

├── app.py                 # Flask application factory
├── main.py               # Application entry point
├── routes.py             # Route definitions and logic
├── db_models.py          # SQLAlchemy database models
├── db_service.py         # Database service layer
├── auth_models.py        # User authentication system
├── email_service.py      # Email functionality
├── templates/            # Jinja2 HTML templates
├── static/              # CSS, JS, and assets
├── data/                # JSON data files
└── render.yaml          # Render deployment configuration

• Backend: Flask, SQLAlchemy, PostgreSQL
• Frontend: Jinja2, Bootstrap 5, Bootstrap Icons
• Deployment: Render.com with PostgreSQL
• Authentication: Custom user management with role-based access
• Reports: ReportLab for PDF generation
• Email: SendGrid integration for notifications

• customers: Customer information and contact details
• cylinders: Cylinder inventory with rental tracking
• rental_history: Complete audit trail of all rental activities

• Foreign key relationships for data integrity
• Indexed fields for performance optimization
• JSON fields for flexible data storage
• Automatic timestamp tracking

• Environment variable protection for secrets
• SQL injection protection via ORM
• Secure password hashing with salt
• Session-based authentication
• Role-based access control

• Database connection pooling
• Pagination for large datasets
• Optimized queries with proper indexing
• Automatic data archiving system
• Gunicorn WSGI server for production

1. Follow the coding standards in replit.md
2. Add comprehensive comments to new code
3. Test database operations thoroughly
4. Update documentation for new features
5. Ensure mobile responsiveness for UI changes

Proprietary software for industrial gas cylinder management.

For deployment and configuration support, refer to:

• RENDER_DEPLOYMENT.md for deployment instructions
• Application logs for debugging information
• Database logs in Render PostgreSQL dashboard