Router to check HP ink levels and notify

levels.sh

#! /opt/bin/bash
# replace these
user="user token"
token="app token"

mypidfile=/tmp/levels.sh.pid
if [ -e $mypidfile ]; then
        exit 0
fi
trap "rm -f $mypidfile" EXIT
echo $$ > "$mypidfile"

if [ -e /dev/lp0 ]; then
        sleep 15
        # check if /dev/lp0 is still around
        # hotplug script gets called both when device is plugged or unplugged
        levels=`hp-info -i|grep 'agent[0-9]-level '|sed -e 's/agent1-/Color /' | sed -e 's/agent2-/Black /' `
        if [ ! -z "$levels" ]; then
                logger -t printer $levels
                curl -d "user=$user" -d "token=$token" -d "message=$levels" https://api.pushover.net/1/messages.json
        fi
fi