mypubip

#!/bin/bash
# 2015.08.29

# Sends public ip if changed.

#How often should we check for ip (in sec)?
often=300
urls=(ipinfo.io/ip ifconfig.me ipecho.net/plain)
nooftimes=10
emailaddr="myemail@server.com"

function getthatip {

# Go through the servers  
 out=""

 for currurl in ${urls[*]}
 do

# Sometimes we get no response
  wcn=1
  while [[ -z "$trueip" && "$wcn" -le "$nooftimes" ]]; do
   #trueip=`curl -m 20 $currurl`
   trueip=`curl --connect-timeout 20 $currurl`
   wcn=$((wcn+1))
   sleep 1
  done
  if [[ $wcn -gt $nooftimes ]]; then
   trueip="Got no response from $currurl"
  fi

# What do we got?
  if [[ $trueip =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]
  then
   out="$trueip"
   nonoftimes=0
   break
  else
   out="$out; $trueip"
  fi
  trueip=""
 done

}

function emailip {

 echo "The ip for $HOSTNAME at $nowis changed from $filedip to $out" | mail -s "$HOSTNAME pubip" $emailaddr

}

nowis=`date +'%y.%m.%d %a, %H:%M'`

# Do we have the dir?
if [ ! -d ~/.mypubip ]; then
 mkdir ~/.mypubip
fi

# Do we have the file?
if [ -e ~/.mypubip/mypubip.txt ]; then

# The file was refreshed at:
 refreshedat=`ls -l --time-style\=+%s ~/.mypubip/mypubip.txt | awk '{ print$6 }' `

# Time now is, then subtract $often:
 shouldhaverefreshed=`date +%s`
 let shouldhaverefreshed=$shouldhaverefreshed-$often

# If file is too old, refresh:
 if [ $refreshedat -lt $shouldhaverefreshed ]; then

  getthatip

  filedip=`cat ~/.mypubip/mypubip.txt`
  echo "$out" > ~/.mypubip/mypubip.txt
  if [ "$out" != "$filedip" ]; then
   echo "The ip at $nowis changed from $filedip to $out"
   emailip
  fi
 fi
else

# If file doesn't exist, refresh:

 getthatip

 echo "$out" > ~/.mypubip/mypubip.txt
 echo "The ip at $nowis is $out"
 emailip
fi