AFC Spool Scan Utility

This utility is designed to interface with a USB QR code scanner and automatically set spool IDs in AFC.

Once the service is running, the utility will listen for events from the connected USB 2D barcode scanner. If a scanned code begins with the magic spoolman prefix web+spoolman:s-, or the scanned code is a URL Base URL\spool\show\, it will send a SET_NEXT_SPOOL_ID SPOOL_ID=# command to AFC for the next spool to be loaded.

Here's the scanner that I'm using, but it's expected that most of the 2D barcode scanners will work with this method: https://www.amazon.com/dp/B0DYY7GLSL

Requirements

• Linux system with evtest package installed.
• User must be a member of the input group to access input devices.

Installation

1. Clone this repository to your home directory:

   cd ~
   git clone https://github.com/kekiefer/afc-spool-scan.git
   cd afc-spool-scan
   

2. Modify the evdev path for your scanner, if necessary

   My scanner doesn't have a unique serial number, and many others will not either, so by default the scanner path is /dev/input/by-id/usb-TMS_HIDKeyBoard_1234567890abcd-event-kbd. You should plug in your scanner, and check this location to see if you need to fix up the EVENT_DEV variable in usb-qr-scanner-read.sh.

   ls -la /dev/input/by-id/
   

3. Install the evtest package:

   sudo apt update
   sudo apt install evtest
   

4. Add your user to the input group:

   sudo usermod -aG input $(whoami)
   

   You must log out and log back in for group changes to take effect. Since a user service is used to run this, this might mean a reboot.

5. Symlink the systemd user service:

   Assuming usb-qr-scanner.service is in the project directory:

   mkdir -p ~/.config/systemd/user
   ln -s ~/afc-spool-scan/usb-qr-scanner.service ~/.config/systemd/user/usb-qr-scanner.service
   

6. Enable and start the systemd user service:

   The service will start automatically when the system is rebooted:

   systemctl --user daemon-reload
   systemctl --user enable usb-qr-scanner.service
   systemctl --user start usb-qr-scanner.service
   

Generating a Moonraker Host QR Code

If you want to change the Moonraker connection at runtime by scanning a QR code, use the included generate-moonraker-qr.sh script to generate one. The QR code encodes the target with the web+moonraker: prefix, which the scanner service recognises and uses to update its active Moonraker scheme, host, and port.

The scanned value after the prefix can be in any of these forms:

Format	Example	Result
hostname	dragonforge	host updated, scheme and port unchanged
hostname:port	dragonforge:1234	host and port updated, scheme unchanged
scheme://hostname	https://dragonforge	scheme and host updated, port unchanged
scheme://hostname:port	https://dragonforge:8443	scheme, host, and port all updated

The defaults are scheme http, host localhost, and port 7125.

Install qrencode if you haven't already:

sudo apt install qrencode

Generate a QR code:

# Default output filename (moonraker-host.png)
./generate-moonraker-qr.sh <target>

# Custom output filename
./generate-moonraker-qr.sh <target> output.png

Examples:

./generate-moonraker-qr.sh dragonforge
./generate-moonraker-qr.sh 192.168.1.100 my-printer.png
./generate-moonraker-qr.sh dragonforge:1234
./generate-moonraker-qr.sh https://dragonforge.localdomain:8443

Scan this code just before scanning your spool to direct subsequent spool scan commands to the new target.