#! /bin/bash
#####################################
# Description: Expose metrics from yum updates.
#
# Phil Connor pconnor@ara.com
# Version 1.0.4.110523
# Based on apt_detect.sh 
######################################
set -u -o pipefail

# shellcheck disable=SC2016
filter_awk_script='
BEGIN { mute=1 }
/Obsoleting Packages/ {
    mute=0
}
mute && /^[[:print:]]+\.[[:print:]]+/ {
    print $3
}
'

check_upgrades() {
    {
        /usr/bin/yum -q check-update |
        /usr/bin/xargs -n3 |
        awk "${filter_awk_script}" |
        sort |
        uniq -c |
        awk '{print "yum_upgrades_pending{origin=\""$2"\"} "$1}'
    }
}

upgrades=$(check_upgrades)

echo '# HELP yum_upgrades_pending Yum package pending updates by origin.'
echo '# TYPE yum_upgrades_pending gauge'
if [[ -n "${upgrades}" ]] ; then
    echo "${upgrades}"
else
    echo 'yum_upgrades_pending{origin=""} 0'
fi

# If yum-utils/dnf-utils is not installed then we skip rendering this metric
if [[ -x /bin/needs-restarting ]] ; then
    echo '# HELP node_reboot_required Node reboot is required for software updates.'
    echo '# TYPE node_reboot_required gauge'
    if /bin/needs-restarting -r  > /dev/null 2>&1 ; then
        echo 'node_reboot_required 0'
    else
        echo 'node_reboot_required 1'
    fi
fi