Ticket Printer Application

A web-based ticket submission system that automatically prints tickets on ESC/POS thermal printers connected to a Raspberry Pi. Users can submit tickets through a simple web interface, which are then automatically printed with timestamps and formatted output.

Perfect for:

• Q&A sessions and feedback collection at events
• Anonymous comment boards
• Interactive installations
• Physical message boards

Things to Buy (Affiliate links)

-Printer: (https://amzn.to/43Vx9DT)

-Raspberry Pi Kit: (https://amzn.to/3XoAZli)

-Receipt Paper: (https://amzn.to/4ag6q8Y)

-You’ll also need a monitor that supports HDMI input. Most do, but here’s a cheap one if you need it: (https://amzn.to/4rsK620)

-Plus a keyboard and mouse, I use this Bluetooth set: (https://amzn.to/4akjutW)

Description

This application provides a complete solution for collecting and printing tickets in physical form. It consists of:

• Web Interface: A clean, responsive frontend that can be hosted on Netlify or run locally
• Backend API: A Flask-based API running on Raspberry Pi that handles printer communication
• Multiple Printer Support: Works with USB, Serial, Network, and Bluetooth-connected printers
• Optional Database Logging: Integrate with Convex to log all submitted tickets
• Spam Protection: Built-in reCAPTCHA integration

The system is designed to be flexible and easy to deploy. You can run everything on a single Raspberry Pi, or separate the frontend (hosted on Netlify) from the backend (on your Pi) for remote access.

Features

• 📝 Simple web interface for ticket submission
• 🖨️ Automatic printing on Netum 58mm thermal printer
• ⏰ Timestamp and date stamping
• 💾 Logged submissions (optional Convex database integration)
• 🌐 Accessible from any device on your network
• 🔒 Built-in reCAPTCHA spam protection

Quick Start

Want to get started quickly? See QUICK_START.md for a step-by-step guide to deploy the application.

For detailed setup instructions, continue reading below.

Configuration

Before starting, you'll need to configure the following:

Required Configuration

1. reCAPTCHA Site Key - Replace YOUR_RECAPTCHA_SITE_KEY in frontend/index.html (line 183)

   • Get your key from Google reCAPTCHA Admin
   • Or set via Netlify environment variable RECAPTCHA_SITE_KEY

2. API URL - Replace YOUR_API_URL_HERE in frontend/index.html (line 217)

   • Set this to your ngrok, Cloudflare tunnel, or direct Raspberry Pi URL
   • Example: https://abc123.ngrok.io or https://your-tunnel.trycloudflare.com

Optional Configuration

3. Convex Database (Optional) - Set CONVEX_DEPLOYMENT in Netlify environment variables
   • Only needed if you want to log tickets to a database
   • If not configured, tickets will still print but won't be logged

See env.example for all available environment variables.

Setup Instructions

1. Install Dependencies

On your Raspberry Pi 4B, install the required Python packages:

# Install Python packages
pip3 install -r requirements.txt

# Install system dependencies for USB printer
sudo apt-get update
sudo apt-get install -y python3-pip python3-dev libusb-1.0-0-dev

# For USB printer access (important!)
sudo usermod -a -G lp dialout pi
sudo apt-get install -y printer-driver-all

2. Connect Your Printer

For USB Connection:

1. Plug in your Netum thermal printer via USB
2. Find the USB vendor and product IDs:

   lsusb

   You should see something like: Bus 001 Device 003: ID 0416:5011
3. The first 4 digits (0416) are the vendor ID
4. The last 4 digits (5011) are the product ID
5. Update the values in app.py if needed

For Serial/GPIO Connection:

If your printer is connected via GPIO serial pins:

sudo raspi-config
# Navigate to Interface Options > Serial Port > Enable

3. Configure the Application

Edit the configuration in app.py or set environment variables:

# For USB printer (default)
export PRINTER_TYPE=usb
export USB_VENDOR=0x0416
export USB_PRODUCT=0x5011

# For serial printer
export PRINTER_TYPE=serial
export SERIAL_PORT=/dev/ttyAMA0

# For network printer
export PRINTER_TYPE=network
export NETWORK_HOST=192.168.1.100

4. Run the Application

python3 app.py

The application will start on http://0.0.0.0:5000

5. Access from Other Devices

Find your Raspberry Pi's IP address:

hostname -I

Then access the web interface from any device on your network:

http://[RASPBERRY_PI_IP]:5000

6. Run as a Service (Optional)

To run the application automatically on boot:

# Create a systemd service file
sudo nano /etc/systemd/system/ticket-printer.service

Add the following content:

[Unit]
Description=Ticket Printer Application
After=network.target

[Service]
Type=simple
User=pi
WorkingDirectory=/home/pi/ticket-printer-app
ExecStart=/usr/bin/python3 /home/pi/ticket-printer-app/app.py
Restart=always

[Install]
WantedBy=multi-user.target

Then enable and start the service:

sudo systemctl daemon-reload
sudo systemctl enable ticket-printer
sudo systemctl start ticket-printer
sudo systemctl status ticket-printer

Usage

1. Open a web browser and navigate to http://[YOUR_PI_IP]:5000
2. Enter your name (optional)
3. Enter your question or comment
4. Click "Print Ticket"
5. The ticket will automatically print with the specified format

Ticket Format

The tickets are printed in this format:

================================
TICKET
--------------------------------
From: [Name]
Time: [Current Time]
Date: [Current Date]
--------------------------------
Question/Comment
[Your message]
--------------------------------
================================

Troubleshooting

Printer Not Detected

If the printer is not detected:

1. Check USB connection
2. Verify printer is powered on
3. Run lsusb to see if the device is recognized
4. Try different USB ports
5. Check permissions: sudo chmod 666 /dev/bus/usb/00X/00Y

Permission Errors

If you get permission errors:

sudo usermod -a -G lp,dialout pi
sudo chmod 666 /dev/ttyUSB0  # or /dev/ttyAMA0 for GPIO
# Then log out and log back in

Test Printer Connection

You can test the printer connection:

python3 << EOF
from escpos.printer import Usb
p = Usb(0x0416, 0x5011)
p.text("Test print\n")
p.cut()
EOF

View Logs

If running as a service:

sudo journalctl -u ticket-printer -f

API Endpoints

• GET / - Web interface
• POST /submit_ticket - Submit a ticket to print
  • Body: {"from_name": "John Doe", "question": "Your question here"}
• GET /health - Health check endpoint

Requirements

• Python 3.7+
• Netum 58mm ESC/POS thermal printer (https://amzn.to/43Vx9DT)
• Raspberry Pi 4B (https://amzn.to/4ooA5jS)
• 58mm Receipt Paper (https://amzn.to/4ag6q8Y)
• Flask web framework
• python-escpos library

Deployment Options

This application supports multiple deployment configurations:

Local Only (Raspberry Pi)

• Run app.py directly on the Raspberry Pi
• Access via local network: http://[PI_IP]:5000

Frontend on Netlify + Backend on Raspberry Pi (Recommended)

• Frontend: Deploy frontend/ folder to Netlify
• Backend: Run backend/api.py on Raspberry Pi
• Expose backend via ngrok or Cloudflare Tunnel
• See README_NETLIFY.md for detailed instructions

Environment Variables

Copy env.example to .env and configure:

cp env.example .env
# Edit .env with your settings

Key variables:

• PRINTER_TYPE - Type of printer connection (usb, serial, network, bluetooth)
• USB_VENDOR / USB_PRODUCT - USB printer IDs (find with lsusb)
• RECAPTCHA_SITE_KEY - Your Google reCAPTCHA site key
• CONVEX_DEPLOYMENT - Convex database URL (optional)

Contributing

Contributions are welcome! Please see CONTRIBUTING.md for guidelines on how to contribute to this project.

Code of Conduct

This project adheres to a Code of Conduct that all contributors are expected to follow. Please read CODE_OF_CONDUCT.md before participating.

Changelog

See CHANGELOG.md for a detailed history of changes and versions.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Feel free to modify and use as needed!