#!/bin/bash
##jsbk.sh
##email: jason [at] schaeferconsulting [dot] com
##505.570.1114
#dmy version
version="aug 24 2021"

########################## USER EDIT BEGINS #############################
## Email to, comma separated list for multiple recipients. host needs to be able to relay local mail. postfix recommended.
to="backup@schaeferconsulting.com"
from="support@schaeferconsulting.com"
## Set "yes" to rely on gnome volume manager (/media/[drivename]). Leave blank for manual mount (requires root priv. and will mount to /mnt)
automount=""
## Name of drive. If you have multiple backup drives, they should be named the same.
drivename="backup"
## Name of directory to write backups in. Leave blank to write to the root of backup drive.
bkdir=""
## If you are in need of assistance, please contact [the following string]
support="Schaefer Consulting at 505.570.1114"
## To bypass the backup commands, for debug purposes set to yes
bypassbk=""

########################## START BACKUP COMMANDS ########################
backup_commands () {
echo "Running backup commands now..." &>> $log
## Enter backup line's here i.e., cp, ssh, rsync ####
## append "||check" to the end of the command to verify if the command ran successfully
## == TAR ==
## exmpl:    /bin/tar zcvf $bklocation/$(/bin/date +%F).tar.gz --exclude media/* /home ||check &>> $log
## == CP ==
## exmpl:    /bin/cp -rvu /home/ $bklocation/new-n-changed ||check &>> $log
## == RSYNC ==
## exmpl:    /usr/bin/rsync -av --delete --stats --exclude media/* /home/ $bklocation/rsync-mirror ||check &>> $log
## == POSTGRES
## exmpl:                /usr/bin/pg_dump -Z 9 -p 5432 -h hostname -U username dbname > $bklocation/dbname_$(/bin/date +%F_%T).sqldump.gz ||check &>> $log
##                           note: postgres auth uses ~/.pgpass containing localhost:5432:db:dbuser:dbpass
## == SMB ==
## exmpl:                cd $bklocation/backup-destination && /usr/bin/smbget -URq smb://user:password@hostname/share &>> $log
## == RDIFF-BACKUP ==
## exmpl:    /usr/bin/rdiff-backup --force --remove-older-than 10M $bklocation/rdiff-backup ||check &>> $log
## exmpl:    /usr/bin/rdiff-backup /home $bklocation/rdiff-backup ||check &>> $log
## == RSNAPSHOT ==
## Use the following options in rsnapshot.conf
## sync_first 1, no_create_root  1, link_dest 1
## exmpl:    /bin/sed -i -e "/^snapshot_root/s,/mnt/.*/\$,${bklocation}/rsnapshot/," /etc/rsnapshot.conf
## exmpl:                                            /usr/bin/rsnapshot sync  || { check &>> $log; return 1; }
## exmpl:    [[ $(/bin/date +%d) == 01       ]] && { /usr/bin/rsnapshot delta || { check &>> $log; return 1; }; }
## exmpl:    [[ $(/bin/date +%A) == Saturday ]] && { /usr/bin/rsnapshot gamma || { check &>> $log; return 1; }; }
## exmpl:                                            /usr/bin/rsnapshot beta  || { check &>> $log; return 1; }

echo "rsnapshot of /home and /etc on $(hostname)" &>> $log
#/bin/sed -i -e "/^snapshot_root/s,/.*\$,${bklocation}/rsnapshot/," /etc/rsnapshot.conf
    echo "  sync..."  &>> $log; /usr/bin/rsnapshot sync  || { check &>> $log; return 1; }
[[ $(/bin/date +%d) == 01       ]] && \
  { echo "  delta..." &>> $log; /usr/bin/rsnapshot delta || { check &>> $log; return 1; }; }
[[ $(/bin/date +%A) == Saturday ]] && \
  { echo "  gamma..." &>> $log; /usr/bin/rsnapshot gamma || { check &>> $log; return 1; }; }
    echo "  beta..."  &>> $log; /usr/bin/rsnapshot beta  || { check &>> $log; return 1; }
echo "rsnapshot done" &>> $log
}

########################### END BACKUP COMMANDS #########################

########################### USER EDIT ENDS ##############################

########################### CRON REFERENCE ##############################
## setup to run on a schedule with cron
## minutes (0-59) | hours (0-23) | day of month (1-31) | month (1-12) | day of week (0-6 or Sun-Sat 0,6) | command
## 0 2 * * * /usr/local/bin/jsbk.sh
## will run at 2:00am every day
## 0 2 1,15 * * /usr/local/bin/jsbk.sh
## will run at 2:00am 1st and 15th of the month

#if you want to see the log on your screen, use log="/dev/stdout" instead
log="/tmp/jsbk.backup.log"
#log="/dev/stdout"
subject="Backup log from $(hostname)"

#mountpoint, for easy reference later
if [ "$automount" = "yes" ]; then mp="/media/$drivename"; else mp="/mnt"; fi

#mount point plus backup dir, for easy reference in backup commands
bklocation="$mp/$bkdir"

starttime=$(/bin/date +%s)

trap caughtsig 1 2 3 6
caughtsig () {
  echo "******************** Caught INTERRUPT SIG 1,2,3, or 6. **********************" &>> $log
  exit 1
}

declare -g failed=""
check () {
  echo "ERROR: A command FAILED!" &>> $log
  failed="failed"
}

error () {
  echo -e "*** Backup is NOT working!" &>> $log
  echo -e "*** Contact technician for service." &>> $log
  echo -e "*** Keep this message for diagnoses" &>> $log
  echo -e "*** Backup Failed on $(/bin/date +%c)\n" &>> $log
  echo -e "Mount Point: $mp\n" &>> $log
  #/bin/mount &>> $log
}

emailend () {
  #calculate running time of backup
  elapsed=$(($(/bin/date +%s) - $starttime))
  printf "Elapsed running time: %dh:%dm:%ds\n" $(($elapsed/3600)) $(($elapsed%3600/60)) $(($elapsed%60)) &>> $log
  echo -e "\nBackup disk space (Size=total space, Used=space in use, Avail=space remaining; M=megabytes, G=gigabytes, T=terabytes):" &>> $log
  df -h $mp &>> $log
  #echo -e "\nLargest backed-up files that either are new or have changed since yesterday:" &>> $log
  #(cd $bklocation/ && /usr/bin/find * -type f -newermt yesterday -exec /bin/ls -dlS {} + |& head -n 4 &>> $log)
  echo -e "---\nIf you are in need of assistance, please contact $support\n" &>> $log
  if [ -z "$automount" ]; then
    /bin/umount $mp &>> $log || { echo -e "Error: Removing hard drive failed\n"; } &>> $log
  fi
  if [ -n "$to" ]; then
    /usr/bin/mail -r "$from" -s "$subject" $to < $log
  else
    echo "no email address specified"
  fi
  /bin/mv $log /tmp/jsbk.last.log
  exit
}

#check if backup is still running or exited without cleanup.
if [ -f $log ]; then
  echo "log ($log) exists. this indicates that $0 may be currently running or exited uncleanly. verify with ps aux |grep $0 and if not running, delete $log." &>> $log
  error
  emailend
fi

[ "$automount" != yes -a -n "$automount" ] && echo ERROR: automount=\"$automount\" is not valid. &>> $log && error && emailend
[ -z "$drivename" ] && echo ERROR: drivename is not declared &>> $log && error && emailend
[ -z "$bkdir" ] && echo fyi, bkdir is not declared
[ -z "$support" ] && echo fyi, support string is empty

#begin
echo "BACKUP LOG" &>> $log
echo "version: $version" &>> $log
echo "server: $(hostname)" &>> $log
echo -e "Backup started on $(/bin/date +%c) \n" &>> $log
if [ ! -d "$mp" ]; then
  echo "Mount point $mp does not exist!" &>> $log
  if [ "$automount" = "yes" ]; then
    echo "be sure drivename=\"$drivename\" is correct and gnome volume mounting is working. Or switch to automount=\"no\"" &>> $log
  fi
  if [ "$automount" = "no" ]; then
    echo "check that $mp exists" &>> $log
  fi
  echo "Also, be sure the drive is plugged in or turned on." &>> $log
  error
  emailend
fi
if [ -z "$automount" ]; then
  #mount drive manually at /mnt
  /bin/mount -o noatime -L $drivename $mp &>> $log || { echo "ERROR: mounting hard drive failed. Be sure drivename=\"$drivename\" is correct. Be sure the drive is plugged in or turned on."; error; emailend; } &>> $log
fi

if [ ! -d "$bklocation" ]; then
  echo bklocation=\"$bklocation\" is not a directory. stripping bkdir, will write files to root of $mp
  bkdir=""
fi

echo "+++ START LOG +++" &>> $log
if [ "$bypassbk" = "yes" ]; then
  touch $bklocation/bypassbk.test
  echo "Bypassing all backup commands for debug purposes" &>> $log
  emailend
else
  #user backup commands function
  backup_commands
fi
echo -e "+++ END LOG +++\n" &>> $log

#check to see if $failed equals zero, if it is then all commands were successful. If not, something failed.
if [ "$failed" = "failed" ]; then
  echo -e "\tERROR: A problem was detected!\n" &>> $log
  error
else
  echo -e "\tSUCCESS: Backup Complete!\n" &>> $log
fi

emailend