check_systemdunit

#!/bin/bash
# ================================================================================
#
# CHECK A SINGLE SYSTEMD SERVICE
#
# -------------------------------------------------------------------------------
# 2023-09-05  v1.0  <axel.hahn@unibe.ch>
# 2020-09-08  v1.1  <axel.hahn@unibe.ch>  add params -s, -l
# ================================================================================

. $( dirname $0 )/inc_pluginfunctions

export self_APPVERSION=1.1

# ----------------------------------------------------------------------
# FUNCTIONS
# ----------------------------------------------------------------------

# show help text
function showHelp(){
    local _self; _self=$(basename $0)
cat <<EOF
$( ph.showImlHelpHeader )

Check a unit using systemctl status.

The status is unknown if the command systemctl is not found.
The status is critical if the service does not exist or is not running.

SYNTAX:
  $_self [-h|-l|-s] UNIT

OPTIONS:

  -h     this help
  -l     list all units
  -s     list service units

  UNIT   Name of a unit - see output of 'systemctl' 

EXAMPLES:

  $_self -s
         list all existing services. For a unit check you need to add the name
         in the 1st column.

  $_self nginx.service
         show status of nginx webservice

EOF
}

# ----------------------------------------------------------------------
# MAIN
# ----------------------------------------------------------------------

ph.hasParamoption "h" "$@"; bOptHelp=$?

if [ $bOptHelp -eq 0 -o $# -eq 0 ]; then
    showHelp
    exit 0
fi

ph.require "systemctl"

# --- list all units
if ph.hasParamoption "l" "$@" ; then
  echo "List of all systemd units:"
  echo
  _list=$( systemctl --no-legend --no-pager )
  for mytype in $( awk '{ print $1 }' <<< "$_list" | grep '\.' | rev| cut -f 1 -d '.' | rev | grep -v '[^a-z]' | sort -u )
  do
    echo "---------- $mytype"
    grep "\.${mytype}" <<< "$_list"
    echo
  done
  exit 0
fi

# --- list service units
if ph.hasParamoption "s" "$@" ; then
  echo "List of service units:"
  echo
  systemctl --no-legend --no-pager --type service
  exit 0
fi

# --- check given unit
_unit="${1}"
_status=$( systemctl --no-pager -l status "${_unit}" 2>&1 )

if ! grep "Active: active (running) " <<< "${_status}" >/dev/null; then
    ph.setStatus critical
fi
ph.status "${_status}"

ph.exit

# ----------------------------------------------------------------------