backup-rsync-ssh.sh

#!/bin/bash
##  Backup to External Drive via sshfs/rsync
##  Author: Oleksii Pylypchuk 
##  github: https://github.com/alpi-ua/backup-site/
##  require packages: bsd-mailx, sshfs

site=
email=alpi@keemail.me
exclude="-x=cache/smarty/\* -x=img/p/\* -x=upload/\* -x=var/cache/\*"   # prestashop settings
site_images="img/p" 

BACKUPS_NUM=3
USER=

# LOCAL SERVER VARS
WORKDIR="/var/backups/local"
SITEDIR=""
BACKUP_DIR=${WORKDIR}/${site}_$(date '+%d-%m-%Y')
SCRIPT_DIR="/var/backups"

MYSQLDB=""
MYSQLUSER=""
MYSQLPASS=""

# REMOTE SERVER VARS
RSERVER=""
RPORT="23"
RUSER=""
RDIR=/var/backups/${RSERVER}

files=${BACKUP_DIR}/${site}_files.zip
images=${BACKUP_DIR}/${site}_images.zip
database=${BACKUP_DIR}/${site}_database.zip
backuplog=${BACKUP_DIR}/${site}_backup.log

FREE_SPACE=$(df -k --output=avail ${PWD} | tail -n1)
SITE_SIZE=$(du -s ${SITEDIR} | cut -f 1)
ATTACHMENT="-f $backuplog"        # Ubuntu : bsd-mailx 8
#ATTACHMENT="-a $backuplog"        # RHEL   : mailx 12+

### FUNCTIONS
function log() {
echo "$(date '+[%d-%m-%Y] %H:%M:%S') | $1" >> $backuplog 
rm -f ${WORKDIR}/error_output
}

function checkjob() {
returncode=$?
if [ ${returncode} -ne 0 ] 
  then
    [[ -f ${backuplog} ]] || ATTACHMENT=""
    log "!! Failed to create a "$2" backup. Return code is ${returncode}. Original message: $(cat ${WORKDIR}/error_output | tr -d '\n')"
    echo "Error backuping ${site} "$2". Program returned code ${returncode}" | mail -s "Error backuping ${site} $2" ${ATTACHMENT} ${email}
    [[ -n $3 ]] && rm -rf "$3" && log "!! deleting unfinished part"
  else
    log "|_ New $2 backup created" 
fi
}

function delete_old() {
OLD_BKP="$(cd $1; ls -1tr | sed 's/^\([^0-9]*\)\([0-9]\+\.txt\)/\2\1/g' | head -1 | sed 's/^\([0-9]\+\.txt\)\(.*\)/\2\1/g')"
rm -rf $1/${OLD_BKP} && log "|_ Removing backup ${OLD_BKP}"
}

function check_rdir() {
RDIR_BACKUP="$1/${site}_backup"
[[ -d ${RDIR_BACKUP} ]] || mkdir -p ${RDIR_BACKUP}
OLD_RBKP=$(find ${RDIR_BACKUP} -type d -mtime +$((${BACKUPS_NUM} - 1)))
[[ -n ${OLD_RBKP} ]] && log "|_ Removing backups older than ${BACKUPS_NUM} days from external share" && rm -rf ${OLD_RBKP}
log "|_ External storage check complete"
}

function upload() {
rsync -re "ssh -p ${RPORT}" ${BACKUP_DIR} ${RUSER}@${RSERVER}:${site}_backup/ &>${WORKDIR}/error_output
returncode=$?
if [ ${returncode} -ne 0 ] 
  then
    [[ -f ${backuplog} ]] || ATTACHMENT=""
    log "-- Error occured. Upload unsuccessful. Return code is ${returncode}. Original message: $(cat ${WORKDIR}/error_output | tr -d '\n')"
    echo "Error occured while uploading "$1" to external share" | mail -s "Error uploading ${site} backup" ${ATTACHMENT}" ${email}"
  else
    log "|_ Upload finished"
  fi  
}

### Installing sudo and sshfs mount script

if [[ `whoami` == 'root' ]]  
  then
    [[ ! -f /etc/sudoers.d/${USER} ]] && \
    echo "${USER}       ALL=NOPASSWD: /usr/bin/fusermount -u ${RDIR}" > /etc/sudoers.d/${USER} && \
    echo "Installing sudo for user ${USER}"
  
    [[ ! -f ${SCRIPT_DIR}/sshfs.sh ]] && \
    echo "Installing sshfs mount script" && cat > ${SCRIPT_DIR}/sshfs.sh <<EOF
#!/bin/bash
[[ \$1 == 'unmount' ]] && sudo /usr/bin/fusermount -u ${RDIR} && exit 0
[[ \$1 == 'mount' ]] && /usr/bin/sshfs -p ${RPORT} ${RUSER}@${RSERVER}: ${RDIR}
EOF
    chmod +x ${SCRIPT_DIR}/sshfs.sh    
    chown ${USER}:${USER} ${RDIR}
    echo "You should generate and install ssh keys from user to remote server"
    
    [[ ! -f /etc/cron.d/backup-${SITE} ]] && \
    echo "Installing cron task for backup in /etc/cron.d" && cat > /etc/cron.d/backup-${USER} <<EOF
0 5 * * * ${USER} $(realpath $0)
EOF
  else
    [[ ! -f /etc/sudoers.d/${USER} ]] && [[ ! -f ${SCRIPT_DIR}/sshfs.sh ]] && \
    echo "First run of this script should happen as 'root'" && exit 0
fi

### SCRIPT STARTS

[[ -d ${BACKUP_DIR} ]] || mkdir -p ${BACKUP_DIR}
[[ -f ${backuplog} ]] || touch ${backuplog} && chown ${USER}:${USER} ${backuplog}

echo "=================================================================" >> ${backuplog}
log "Starting backup to ${site}"

[ ${FREE_SPACE} -lt ${SITE_SIZE} ] && log "Not enough free space on local host. Removing old backup" && delete_old ${WORKDIR} 

log "Backuping database"
mysqldump -u ${MYSQLUSER} -p${MYSQLPASS} ${MYSQLDB} > ${BACKUP_DIR}/${site}.sql

cd ${BACKUP_DIR} ; zip -rq ${database} ${site}.sql &>${WORKDIR}/error_output
checkjob "$?" "database" "${database}" && rm -rf ${site}.sql

log "Archiving files"
cd ${SITEDIR} ; zip ${exclude} -rq ${files} . &>${WORKDIR}/error_output
checkjob "$?" "files" "${files}"

log "Archiving images"
cd ${SITEDIR} ; zip -rq ${images} ${site_images} &>${WORKDIR}/error_output
checkjob "$?" "images" "${images}"

log "Archiving system settings"
zip -rq ${BACKUP_DIR}/etc.zip /etc /var/spool/crontabs /var/backups/backup.sh &>/dev/null

log "Working with external storage"
if grep ${RDIR} /proc/mounts | grep -qs "user_id=$(getent passwd | grep ${USER} | head -1 | cut -d':' -f 4)"
  then 
    log "|_ External storage is mounted"
    check_rdir ${RDIR}
  else
    [[ ! -d $RDIR ]] && log "|_ Unpropper mount of external storage. Remounting" && ${SCRIPT_DIR}/sshfs.sh unmount
    ${SCRIPT_DIR}/sshfs.sh mount
    check_rdir ${RDIR}
    ${SCRIPT_DIR}/sshfs.sh unmount
fi

log "Uploading backup"
upload ${BACKUP_DIR}

### IN CASE WE ARE UNDER ROOT
[ `whoami` == 'root' ] && chown -R ${USER}:${USER} ${WORKDIR}