Ticketing System

This project generates, prints, and scans tickets with QR codes. It uses Python, Flask, ReportLab, and PyPDF2. The system is now deployable both locally and via a public server using Nginx and HTTPS.

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Objective

• Automate creation of event tickets with unique QR codes.
• Provide a secure local validation system accessible via mobile devices.
• Ensure smooth scanning and validation at event entrances without relying on third-party services.

Methodology

• Ticket generation:

  • Configurable event name and number of tickets in config.py.
  • Templates defined as PDFs, overlaid with unique QR codes.
  • Ticket data stored in SQLite (tickets.db), with backup for each event.

• Validation server:

  • Flask app with HTTPS (self-signed certificates).
  • Endpoints to validate tickets in real-time.
  • Automatic logging of scans and status updates.

• Scanning page:

  • Accessible via QR code linking to https://<server-ip>:8000/scan.
  • Uses ZXing JS for live camera decoding.
  • Displays clear status messages (valid, already used, invalid).
  • 3-second buffer between scans.

Usage Workflow

1. Generate tickets

   • Edit config.py (event name, ticket count, template path).
   • Run python generate_tickets.py.
   • Outputs: tickets with QR codes, database, and CSV with ticket URLs.

2. Start validation server

   • Run python app.py (or flask run with certificate and key).
   • Server available at https://<LAN-IP>:8000/.

3. Scan tickets

   • Staff connect to event Wi-Fi, open scan QR code in browser.
   • Accept certificate and allow camera access.
   • Page shows validation result in large colored text.

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For Developers

1. Prerequisites

Local System Requirements (for generating tickets)

• Python 3.8+ installed (Windows or Linux)
• Git and OpenSSL (for creating SSL certs if needed)
• On Windows: allow inbound TCP port 8000 in Windows Firewall
• Make sure all devices are connected to the same network when testing locally

VPS Server Requirements (for public deployment)

• A public VPS (e.g. Hetzner Cloud) with Ubuntu 22.04
• A domain name (e.g. tickets.danielnetzl.com)
• Domain DNS pointing to your VPS (A record)
• sudo access via SSH (preferably using SSH keys)

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2. Clone & Install (on any system)

git clone <repo-url> ticketing_system
cd ticketing_system
python -m venv venv
source venv/bin/activate  # Or .venv\Scripts\activate on Windows
pip install -r requirements.txt

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3. Generate Tickets

1. Edit config.py and set:

   • EVENT (name of the event)
   • N_TICKETS
   • BASE_PATH and other layout config if needed
   • URL = "tickets.danielnetzl.com" (no prefix)

2. Place your event template PDF into ticket_templates/ named as {EVENT}.pdf.

3. Generate everything (QR codes, PDFs, database, backup):

python generate_tickets.py

This creates:

• events/{EVENT}/tickets.db
• qr_codes/ + scan_page.png
• ticket_urls.csv
• tickets/ as printable PDFs
• A full backup in bkp/{EVENT}

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4. Deploy to VPS with Nginx + HTTPS

A. Set up server

On your VPS:

sudo apt update
sudo apt install nginx python3-pip python3-venv git ufw -y
sudo ufw allow OpenSSH
sudo ufw allow 'Nginx Full'
sudo ufw enable

B. Clone your project and set up Python

adduser tickets
usermod -aG sudo tickets
su - tickets
git clone <repo> ticketing_system
cd ticketing_system
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt

C. Run the app via systemd

Create /etc/systemd/system/tickets.service:

[Unit]
Description=Gunicorn for Ticket App
After=network.target

[Service]
User=tickets
Group=www-data
WorkingDirectory=/home/tickets/ticketing_system
Environment="PATH=/home/tickets/ticketing_system/venv/bin"
ExecStart=/home/tickets/ticketing_system/venv/bin/gunicorn -w 4 -b 127.0.0.1:8000 app:app

[Install]
WantedBy=multi-user.target

Then:

sudo systemctl daemon-reexec
sudo systemctl enable tickets
sudo systemctl start tickets

Check with:

sudo systemctl status tickets

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D. Configure Nginx

Edit /etc/nginx/sites-available/tickets:

server {
    listen 80;
    server_name tickets.danielnetzl.com;

    location / {
        proxy_pass http://127.0.0.1:8000/;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}

Then:

sudo ln -s /etc/nginx/sites-available/tickets /etc/nginx/sites-enabled/
sudo rm /etc/nginx/sites-enabled/default
sudo nginx -t
sudo systemctl reload nginx

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E. Enable HTTPS with Let's Encrypt

sudo apt install certbot python3-certbot-nginx -y
sudo certbot --nginx

Choose to redirect HTTP to HTTPS when prompted.

Now your app is securely available at:

https://tickets.danielnetzl.com/scan

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5. Scanner Webpage

• URL: https://tickets.danielnetzl.com/scan
• QR code for this page is saved as scan_page.png
• Uses live camera access (requires HTTPS)
• 3-second delay between scans to avoid double scans

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6. Instructions for Entrance Staff

This guide is for staff scanning tickets on phones/tablets.

Setup

1. Use any browser except Ecosia (won't allow camera access).

2. Connect to mobile data or event Wi-Fi.

3. Scan the scan_page.png QR code and open the link in Safari/Chrome.

4. When prompted:

   • Allow camera access
   • Accept HTTPS certificate (if needed)

Tip: Tap Share → Zum Home-Bildschirm to pin it as a full-screen app.

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During the Event

• Hold the QR code clearly in the camera frame

• A message will appear:

  • ✅ Ticket gültig → allow entry
  • ❌ Bereits verwendet → reject
  • ❌ Ungültig → reject

• Wait 3 seconds before the next scan

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🛠 Troubleshooting

• Camera not available: Make sure you use Safari or Chrome + HTTPS
• Scan not detected: Check lighting, glare, or focus
• Tab closes: Re-open the scan URL, clear browser cache if needed

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7. Developer Notes

• Run python generate_tickets.py whenever you want to:

  • Create a new event
  • Regenerate QR codes

• All output is placed under events/{EVENT} and backed up

• The app auto-loads the correct database for the current event

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You're all set!

Access:

https://tickets.danielnetzl.com/scan

Support: Ask Daniel if anything breaks.