ftp_monitor_json.sh

#!/bin/bash

readonly script_path=$(readlink -f $0)
readonly base_dir=$(dirname $script_path)
# get file name without extension
base_name="${script_path##*/}"
readonly base_name="${base_name%.*}"
readonly cfg="$base_dir/$base_name.cfg"
readonly item_list=$(cat $cfg | sed '/^\s*$/d' |awk 'BEGIN {ORS = " "} {if($1 !~/^#/) print $0}'| sed -e 's/[ \t]*$//')
readonly nc_default="nc"
readonly nc_custom="/opt/IBM/tools/tivoli/nc"

function make_file() {
  if [ ! -f "$1" ]; then
    touch "$1" 2>/dev/null
    chmod 777 "$1" 2>/dev/null
  fi
}

#param1: command
function is_command() {
  local result=$(whereis $1 | awk -F ":" '{print $2}' | sed '/^\s*$/d')
  if [[ "$result" == "" ]]; then
    echo -1
  else
    echo 0
  fi
}

#param1: ip address
function ping_test() {
  local result=$(ping -c 1 -W 1 $1 2>/dev/null| awk 'match($0, /[0-9]+% packet loss/) {print substr($0, RSTART, index($0, "%")-RSTART)}')
  if [[ "$result" =~ "unknown" ]] || [[ "$result" == "" ]]; then
    echo -1
  else
    echo $result
  fi
}

#param1: host
#param2: port
#param3: nc path
function tcp_test() {
  local result=$($3 -zw5 $1 $2)
  if [[ "$result" == *"succeeded"* ]]; then
    echo 0
  else
    echo -1
  fi
}

function init() {
  $(make_file "$cfg")
}

function main() {
  $(init)
  
  local nc_path=$nc_default
  if (( $(is_command $nc_default) != 0 )); then
    nc_path=$nc_custom
  fi
  
  local json_str="";
  local tcp_status=""
  local timestamp="$(date +"%F %T:%3N")"
  
  if [[ "$item_list" == "" ]]; then
    echo "{\"FTP\":[]}"
    return 0
  fi
  
  for item in ${item_list[*]}; do
    local label=$(echo $item| awk  -F ';' '{print $1}')
    local host=$(echo $item| awk  -F ';' '{print $2}')
    local port=$(echo $item| awk  -F ';' '{print $3}')
    
    if [[ "$host" == "" || "$port" == "" ]]; then
      continue
    fi
    local result=$(tcp_test $host $port $nc_path)
    if (( $result == 0 )); then
      tcp_status="succeeded"
    else
      tcp_status="failed"
    fi
    
    json_str=$json_str"{\"label\":\"$label\",\"host\":\"$host\",\"timestamp\":\"$timestamp\",\"port\":\"$port\",\"tcp_status\":\"$tcp_status\"},"
  done
  
  json_str="{\"FTP\":["$(echo $json_str | sed 's\,$\\g')"]}"
  echo $json_str
}

result=$(main)
if [[ "$result" != "" ]]; then
  echo $result
fi