Barcode Scanner + Python Script = Open URLs contained in QR Codes

System Basics

• Barcode Scanner = Tera D5100 (USB device configured for a "Virtual COM connection")
• Tera D5100 uses generic Windows drivers
• On my machine, the D5100 appears in Device Manager under Ports (COM & LPT) as USB-SERIAL CH340 (COM3)
• Tested on a Windows 10 machine
• Tested using Python 3.9.12

Operational Basics

• upon program launch, you will be shown a list of available COM ports and prompted to make a selection
  • program assumes a baud rate of 9600
• once connected, the program should sit quietly in the background until a QR Code is scanned
• once a QR code is scanned a new broswer tab will open and will be directed to the URL baked into the QR Code
  • New tabs should open in your default browser
  • As written, the program is 'stupid' in the sense that it does not check to confirm that the scanned code is a legitimate URL
  • If you scan the UPC on a box of cereal it will try to navigate to http://cheerios_upc/
  • If the scanned code does not begin with http:// or www. or a typical url scheme, webbrowser assumes you are trying to open a file
  • On my Windows machine, webbrowser tries to open files using... gasp!... Internet Explorer (not my default browser!)
  • IMPORTANT DETAIL: the program assumes that the scanned QR Code terminates with a carriage return (\r aka 0x0D in hex)

Quick Install Guide (Windows 10)

• Make sure python is installed
  • open a command prompt and type python --version
  • if you don't have python go to python.org and install version 3.9 (any version 3.x will likely work)
• Create a folder to store the qr_scan_url.py script (e.g. C:\Documents\Code\qr_scan_url\)
• Copy the qr_scan_url.py script from this repo into your newly created folder
• Fire up VScode
  • go to File → Open Folder
  • select the folder you just created
  • go into the terminal (to open a terminal go to View → Terminal)
  • you should be positioned inside your newly created directory (e.g. C:\Documents\Code\qr_scan_url\)
  • type python -m venv venv .... this creates a virtual environment
  • type .\venv\Scripts\activate .... this activates the virtual environment
  • type pip install pyserial .... this installs the pySerial package inside the virtual environment
  • to confirm that pyserial has installed correctly type pip list
  • open the qr_scan_url.py script (should be visible in the left side Explorer window)
  • you should be able to run the program by clicking on the Run Python File icon in the upper right corner (looks like a Play button)