quality_recticel/old code/documentation/README.md

Quality Recticel Windows Print Service

🏗️ Technical Architecture

Local Windows service providing REST API for silent PDF printing via Chrome extension integration.

┌─────────────────────────────────────────────────────────────┐
│                    Quality Recticel Web App                 │
│                  (print_module.html)                       │
└─────────────────────┬───────────────────────────────────────┘
                      │ HTTP Request
                      ▼
┌─────────────────────────────────────────────────────────────┐
│              Windows Print Service                          │
│                (localhost:8765)                            │
│  ┌─────────────┐  ┌──────────────┐  ┌─────────────────┐   │
│  │   Flask     │  │    CORS      │  │   PDF Handler   │   │
│  │   Server    │  │   Support    │  │                 │   │
│  └─────────────┘  └──────────────┘  └─────────────────┘   │
└─────────────────────┬───────────────────────────────────────┘
                      │ Native Messaging
                      ▼
┌─────────────────────────────────────────────────────────────┐
│                Chrome Extension                             │
│  ┌─────────────┐  ┌──────────────┐  ┌─────────────────┐   │
│  │ Background  │  │  Content     │  │     Popup       │   │
│  │ Service     │  │  Script      │  │     UI          │   │
│  │ Worker      │  │              │  │                 │   │
│  └─────────────┘  └──────────────┘  └─────────────────┘   │
└─────────────────────┬───────────────────────────────────────┘
                      │ Windows API
                      ▼
┌─────────────────────────────────────────────────────────────┐
│                Windows Print System                         │
└─────────────────────────────────────────────────────────────┘

📁 Project Structure

windows_print_service/
├── 📄 print_service.py           # Main Flask service
├── 📄 service_manager.py         # Windows service wrapper  
├── 📄 install_service.bat        # Installation script
├── 📄 INSTALLATION_GUIDE.md      # Complete documentation
├── 📄 QUICK_SETUP.md            # User quick reference  
├── 📄 README.md                 # This file
└── 📁 chrome_extension/         # Chrome extension
    ├── 📄 manifest.json         # Extension manifest v3
    ├── 📄 background.js         # Service worker
    ├── 📄 content.js           # Page content integration
    ├── 📄 popup.html           # Extension popup UI
    ├── 📄 popup.js            # Popup functionality
    └── 📁 icons/              # Extension icons

🚀 API Endpoints

Base URL: http://localhost:8765

Endpoint	Method	Description	Request Body	Response
/health	GET	Service health check	None	{"status": "healthy", ...}
/printers	GET	List available printers	None	{"printers": [...]}
/print/pdf	POST	Print PDF from URL	{"url": "...", "printer": "..."}	{"success": true, ...}
/print/silent	POST	Silent print with metadata	{"pdf_url": "...", "order_id": "..."}	{"success": true, ...}

Example API Usage

// Health Check
const health = await fetch('http://localhost:8765/health');
const status = await health.json();

// Silent Print
const printRequest = {
    pdf_url: 'http://localhost:5000/generate_labels_pdf/123',
    printer_name: 'default',
    copies: 1,
    silent: true,
    order_id: '123',
    quantity: '10'
};

const response = await fetch('http://localhost:8765/print/silent', {
    method: 'POST',
    headers: {'Content-Type': 'application/json'},
    body: JSON.stringify(printRequest)
});

🔧 Development Setup

Prerequisites

• Python 3.8+
• Windows 10/11
• Chrome Browser
• Administrator privileges

Local Development

# Clone/download the project
cd windows_print_service

# Install dependencies
pip install flask flask-cors requests pywin32

# Run development server (not as service)
python print_service.py

# Install as Windows service
python service_manager.py install

# Service management
python service_manager.py start
python service_manager.py stop  
python service_manager.py restart
python service_manager.py uninstall

Chrome Extension Development

# Load extension in Chrome
chrome://extensions/ → Developer mode ON → Load unpacked

# Debug extension
chrome://extensions/ → Details → Background page (for service worker)
chrome://extensions/ → Details → Inspect views (for popup)

📋 Configuration

Service Configuration (print_service.py)

class WindowsPrintService:
    def __init__(self, host='127.0.0.1', port=8765):
        self.host = host      # Localhost binding only
        self.port = port      # Service port
        self.app = Flask(__name__)

Chrome Extension Permissions (manifest.json)

{
    "permissions": [
        "printing",           // Access to printer API
        "nativeMessaging",   // Communication with Windows service
        "activeTab",         // Current tab access
        "storage"           // Extension settings storage
    ]
}

🔄 Integration Flow

1. Service Detection

// Web page detects service availability
const isServiceAvailable = await checkServiceHealth();
updatePrintButton(isServiceAvailable);

2. Print Request Flow

User clicks print → Web app → Windows service → Chrome extension → Printer

3. Fallback Mechanism

Service unavailable → Fallback to PDF download → Manual printing

🛠️ Customization

Adding New Print Options

# In print_service.py
@app.route('/print/custom', methods=['POST'])
def print_custom():
    data = request.json
    # Custom print logic here
    return jsonify({'success': True})

Modifying Chrome Extension

// In background.js - Add new message handler
chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
    if (message.type === 'CUSTOM_PRINT') {
        // Custom print logic
    }
});

Web Application Integration

// In print_module.html - Modify print function
async function customPrintFunction(orderId) {
    const response = await fetch('http://localhost:8765/print/custom', {
        method: 'POST',
        body: JSON.stringify({orderId, customOptions: {...}})
    });
}

🧪 Testing

Unit Tests (Future Enhancement)

# test_print_service.py
import unittest
from print_service import WindowsPrintService

class TestPrintService(unittest.TestCase):
    def test_health_endpoint(self):
        # Test implementation
        pass

Manual Testing Checklist

• Service starts automatically on Windows boot
• API endpoints respond correctly
• Chrome extension loads without errors
• Print jobs execute successfully
• Fallback works when service unavailable
• Firewall allows port 8765 traffic

📊 Monitoring & Logging

Log Files

• Service Log: print_service.log (Flask application logs)
• Windows Event Log: Windows Services logs
• Chrome DevTools: Extension console logs

Health Monitoring

# Monitor service health
import requests
try:
    response = requests.get('http://localhost:8765/health', timeout=5)
    if response.status_code == 200:
        print("✅ Service healthy")
except:
    print("❌ Service unavailable")

🔒 Security Considerations

Network Security

• Localhost Only: Service binds to 127.0.0.1 (no external access)
• No Authentication: Relies on local machine security
• Firewall Rule: Port 8765 opened for local connections only

Chrome Extension Security

• Manifest V3: Latest security standards
• Minimal Permissions: Only necessary permissions requested
• Sandboxed: Runs in Chrome's security sandbox

Windows Service Security

• System Service: Runs with appropriate Windows service privileges
• Print Permissions: Requires printer access (normal for print services)

🚀 Deployment

Production Deployment

1. Package Distribution:

# Create deployment package
zip -r quality_recticel_print_service.zip windows_print_service/

2. Installation Script: Use install_service.bat for end users

3. Group Policy Deployment: Deploy Chrome extension via enterprise policies

Enterprise Considerations

• Silent Installation: Modify install_service.bat for unattended install
• Registry Deployment: Pre-configure Chrome extension registry entries
• Network Policies: Ensure firewall policies allow localhost:8765

📚 Dependencies

Python Packages

flask>=2.3.0          # Web framework
flask-cors>=4.0.0     # CORS support
requests>=2.31.0      # HTTP client
pywin32>=306          # Windows service integration

Chrome APIs

• chrome.printing.* - Printing functionality
• chrome.runtime.* - Extension messaging
• chrome.nativeMessaging.* - Native app communication

🐛 Debugging

Common Debug Commands

# Check service status
sc query QualityRecticelPrintService

# Test API manually  
curl http://localhost:8765/health

# Check listening ports
netstat -an | findstr :8765

# View service logs
type print_service.log

Chrome Extension Debugging

// In background.js - Add debug logging
console.log('Print request received:', message);

// In popup.js - Test API connection
fetch('http://localhost:8765/health')
    .then(r => r.json())
    .then(data => console.log('Service status:', data));

---

📄 License & Support

Project: Quality Recticel Print Service
Version: 1.0
Compatibility: Windows 10/11, Chrome 88+
Maintenance: Zero-maintenance after installation

For technical support, refer to INSTALLATION_GUIDE.md troubleshooting section.