Programmatically adds an AirPrint printer, ideally with an icon

Install_AirPrint_Printer.sh

#!/bin/bash

# Use the built-in ipp2ppd tool to create a PPD file for AirPrint
# Add icon to PPD (if we can get one) and install the printer

# Required printer info
readonly PRINTER_IP='XXX.XXX.XXX.XXX'
readonly PRINTER_NAME='PRINTER_NAME'
readonly PRINTER_DISPLAY_NAME='PRINTER NAME'
readonly PRINTER_LOCATION='PRINTER LOCATION'
# Requiring icon will prevent install if we can't get it
readonly REQUIRE_ICON=true
#readonly REQUIRE_ICON=false
# Number of seconds to wait for TCP verification before exiting
readonly CHECK_TIMEOUT=2
# Custom PPD info
readonly PPD_PATH='/tmp'
readonly PPD="${PPD_PATH}/${PRINTER_NAME}.ppd"
# Base info
readonly AIR_PPD='/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/PrintCore.framework/Versions/A/Resources/AirPrint.ppd'
readonly EXE='/System/Library/Printers/Libraries/ipp2ppd'
readonly ICON_PATH='/Library/Printers/Icons'
readonly ICON="${ICON_PATH}/${PRINTER_NAME}.icns"

AppendPPDIcon() {
	# Verify we have a file
	if [ ! -f "$ICON" ] && [ "$ICON_AVAILABLE" != "false" ]; then
		/bin/echo "Don't have an icon. Exiting..."
		exit 1
	fi

	/bin/echo "Appending ${ICON} to ${PPD}..."
	# Append the icon to the PPD
	/bin/echo "*APPrinterIconPath: \"${ICON}\"" >> "${PPD}"
}

CheckPrinter() {
	# Verify we can communicate with the printer via the AirPrint port via TCP
	local CHECK=$(/usr/bin/nc -G ${CHECK_TIMEOUT} -z ${PRINTER_IP} 631 2&> /dev/null; /bin/echo $?)

	if [ "$CHECK" != 0 ]; then
		/bin/echo "Cannot communicate with ${PRINTER_IP} on port 631/tcp. Exiting..."
		exit 1
	fi
}

CheckIcon() {
	# Query & parse printer icon, largest usually last?
	readonly PRINTER_ICON=$(/usr/bin/ipptool -tv ipp://${PRINTER_IP}/ipp/print get-printer-attributes.test \
	| /usr/bin/awk -F, '/printer-icons/ {print $NF}')

	# Verify we have an icon to download
	if [ -z "$PRINTER_ICON" ] && [ "$REQUIRE_ICON" = "true" ]; then
		/bin/echo "Did not successfully query a printer icon. Will not install printer. Exiting..."
		exit 1
	elif [ -z "$PRINTER_ICON" ]; then
		/bin/echo "Did not successfully query printer icon. Will continue with printer install..."
		readonly ICON_AVAILABLE=false
	fi

	/bin/echo "Downloading printer icon from ${PRINTER_ICON} to ${ICON}..."
	# Download the PNG icon and make it an .icns file
	/usr/bin/curl -skL "$PRINTER_ICON" -o "$ICON"
	
	# Did we actually write an icon successfully?
	STATUS=$(echo $?)
	if [[ "${STATUS}" != 0 ]]; then
		/bin/echo ""
		/bin/echo "Was not able to write the file ${ICON}..."
		/bin/echo "Does the user running this script have the ability to write to ${ICON_PATH}?"
		/bin/echo "If not, either run with 'sudo' or choose a different location to write the icon file."
		exit 1 
	fi
}

CreatePPD() {
	# Create the PPD file
	/bin/echo "Creating the .ppd file at ${PPD}..."
	$EXE ipp://${PRINTER_IP} "$AIR_PPD" > "$PPD"
}

InstallPrinter() {
	/bin/echo "Installing printer..."
	/usr/sbin/lpadmin -p ${PRINTER_NAME} -D "${PRINTER_DISPLAY_NAME}" -L "${PRINTER_LOCATION}" -E -v ipp://${PRINTER_IP} -P ${PPD} -o printer-is-shared=false
}

main() {
	CheckPrinter
	CreatePPD
	CheckIcon
	AppendPPDIcon
	InstallPrinter
}

main "@"

bfaulkner-scc ... perhaps an expired certificate? A bad cert might cause printing failure if trying to talk to printer with ipps (instead of un-encrypted ipp). I noticed when I share a printer in macos, my chromebook will let me add and save the printer, and the chromebook is using ipps to talk to the macos cups server. In an ideal world all traffic to the printer would be encrypted (ipps or https) rather than un-encrypted methods like ipp, http, lpd, port 9100, etc. I'm looking for advice on getting all this working with ipps or https if anyone has done so.