{%- from "xtrabackup/map.jinja" import server with context %}
{%- from "xtrabackup/map.jinja" import client with context %}

#!/bin/bash
#
# Script to create full and incremental backups (for all databases on server) using innobackupex from Percona.
# http://www.percona.com/doc/percona-xtrabackup/innobackupex/innobackupex_script.html
#
# Every time it runs will generate an incremental backup except for the first time (full backup).
# FULLBACKUPLIFE variable will define your full backups schedule.
set -eo pipefail

usage () {
  echo ""
  echo "USAGE: "
  echo "  innobackupex-runner.sh [-s -f -h -c]"
  echo "     -s makes the script to skip the cleanup"
  echo "     -f forces the script to run the full backup instead of an incremental one"
  echo "     -h shows this help"
  echo "     -c run only cleanup (no backup will be done)"
}

SKIPCLEANUP="false"
FORCEFULL="false"
USEROPTIONS="--user={{ client.database.user }} --password={{ client.database.password }}{%- if client.database.host is defined %} --host {{ client.database.host }} --port {{ client.database.get('port', '3306') }}{%- else %} --socket=/var/run/mysqld/mysqld.sock{%- endif %}"
#TMPFILE="/var/log/backups/innobackupex-runner.$$.tmp"
LOGDIR="/var/log/backups"
TMPFILE="/var/log/backups/innobackupex-runner.log"
MYCNF="/etc/mysql/my.cnf"
MYSQL="/usr/bin/mysql"
MYSQLADMIN="/usr/bin/mysqladmin"
BACKUPDIR="{{ client.backup_dir }}" # Client side backups base directory
SERVERBACKUPDIR="{{ server.backup_dir }}" # Server side backups base directory
SERVERBACKUPHOST="{{ client.target.host }}"
FULLBACKUPDIR="$BACKUPDIR/full" # Full backups directory
INCRBACKUPDIR="$BACKUPDIR/incr" # Incremental backups directory
KEEP="{{ client.full_backups_to_keep }}" # Number of full backups (and its incrementals) to keep
{%- if client.backup_times is defined %}
INCRBEFOREFULL="{{ client.incr_before_full }}"
{%- else %}
HOURSFULLBACKUPLIFE="{{ client.hours_before_full }}" # Lifetime of the latest full backup in hours
FULLBACKUPLIFE="$(( $HOURSFULLBACKUPLIFE * 60 * 60 ))"
{%- endif %}
rsyncLog="/var/log/backups/innobackupex-rsync.log"
{%- if client.compression is defined %}
compression="{{ client.compression }}"
{%- else %}
compression="false"
{%- endif %}
{%- if client.rsync_tables is defined %}
rsyncTables="--rsync"
{%- else %}
rsyncTables=""
{%- endif %}
{%- if client.compression_threads is defined %}
compression_threads="{{ client.compression_threads }}"
{%- else %}
compression_threads="1"
{%- endif %}
{%- if client.throttle is defined and client.throttle|int > 0 %}
throttle="--throttle {{ client.throttle }}"
{%- else %}
throttle=""
{%- endif %}
{%- if client.backup_times is defined %}
BACKUPTIME="true"
{%- endif %}

# Grab start time
STARTED_AT="$(date +%s)"

#############################################################################
# Display error message and exit
#############################################################################
error()
{
  echo "$1" 1>&2
  exit 1
}

function prerequisites()
{
  # Check prerequisites before proceeding
  if [ ! -d $BACKUPDIR ]; then
    error "Backup destination directory: $BACKUPDIR does not exist."
  fi

  if [ -z "$($MYSQLADMIN $USEROPTIONS status | grep 'Uptime')" ] ; then
    error "HALTED: MySQL does not appear to be running."
  fi

  if ! $(echo 'exit' | $MYSQL -s $USEROPTIONS) ; then
    error "HALTED: Supplied mysql username or password appears to be incorrect (not copied here for security, see script)."
  fi

  # Some info output
  echo "----------------------------"
  echo "$0: MySQL backup script"
  echo "started: $(date)"
  echo

  if [ ! -d $LOGDIR ]; then
    echo "Creating destination directory $LOGDIR."
    mkdir -p $LOGDIR
  fi
  if [ ! -d $FULLBACKUPDIR ]; then
    echo "Creating destination directory $FULLBACKUPDIR".
    mkdir -p $FULLBACKUPDIR
  fi
  if [ ! -d $INCRBACKUPDIR ]; then
    echo "Creating destination directory $INCRBACKUPDIR".
    mkdir -p $INCRBACKUPDIR
  fi

  # Space check
  if [ $(df $BACKUPDIR | awk '{ print $5 }' | tail -n1 | cut -d '%' -f1) -gt 95 ]; then
    error "There is not enough space on disk."
  fi

}

function backup()
{
  # Find latest full backup
  LATEST_FULL="$(find $FULLBACKUPDIR -mindepth 1 -maxdepth 1 -type d -printf "%P\n" | sort -nr | head -1)"

  # Get latest backup last modification time
  LATEST_FULL_CREATED_AT="$(stat -c %Y $FULLBACKUPDIR/$LATEST_FULL)"

  # If compression is enabled, pass it on to the backup command
  if [ "$compression" = True ]; then
    compress="--compress"
    compression_threads="--compress-threads=$compression_threads"
    echo "Setting compression to True"
    echo
  else
    compress=
    compression_threads=
  fi

  if [ "$BACKUPTIME" != true ]; then
    # Run an incremental backup if latest full is still valid. Otherwise, run a new full one.
    if [ "$LATEST_FULL" -a $(expr $LATEST_FULL_CREATED_AT + $FULLBACKUPLIFE + 5) -ge $STARTED_AT ] && [ "$FORCEFULL" != true ] ; then
      # Create incremental backups dir if not exists.
      TMPINCRDIR="$INCRBACKUPDIR/$LATEST_FULL"
      mkdir -p $TMPINCRDIR

      # Find latest incremental backup.
      LATEST_INCR=$(find $TMPINCRDIR -mindepth 1 -maxdepth 1 -type d | sort -nr | head -1)

      # If this is the first incremental, use the full as base. Otherwise, use the latest incremental as base.
      if [ ! $LATEST_INCR ] ; then
        INCRBASEDIR=$FULLBACKUPDIR/$LATEST_FULL
      else
        INCRBASEDIR=$LATEST_INCR
      fi

      echo "Running new incremental backup using $INCRBASEDIR as base."
      innobackupex --defaults-file=$MYCNF $USEROPTIONS $rsyncTables $throttle $compress $compression_threads --incremental $TMPINCRDIR --incremental-basedir $INCRBASEDIR 2>&1 | tee $TMPFILE
    else
      echo "Running new full backup."
      innobackupex --defaults-file=$MYCNF $USEROPTIONS $rsyncTables $throttle $compress $compression_threads $FULLBACKUPDIR 2>&1 | tee $TMPFILE
    fi
  else
    # Get number of full and incremental backups
    NUMBER_OF_FULL="$(find $FULLBACKUPDIR -maxdepth 1 -mindepth 1 -type d -print| wc -l)"
    NUMBER_OF_INCR="$(find $INCRBACKUPDIR -maxdepth 2 -mindepth 2 -type d -print| wc -l)"
    echo "Number of Full backups stored: " $NUMBER_OF_FULL
    echo "Number of Incremental backups stored: " $NUMBER_OF_INCR
    echo "----------------------------"
    #If number of incremental mod number of full backups to keep equals 1, run full backup, otherwise run incremental
    if [ $(( ($NUMBER_OF_INCR + $NUMBER_OF_FULL) % ($INCRBEFOREFULL + 1) )) -eq 0 ] || [ "$FORCEFULL" == true ] ; then
      echo "Running new full backup."
      innobackupex --defaults-file=$MYCNF $USEROPTIONS $rsyncTables $compress $compression_threads $FULLBACKUPDIR 2>&1 | tee $TMPFILE
    else
      # Create incremental backups dir if not exists.
      TMPINCRDIR=$INCRBACKUPDIR/$LATEST_FULL
      mkdir -p $TMPINCRDIR

      # Find latest incremental backup.
      LATEST_INCR=$(find $TMPINCRDIR -mindepth 1 -maxdepth 1 -type d | sort -nr | head -1)

      # If this is the first incremental, use the full as base. Otherwise, use the latest incremental as base.
      if [ ! $LATEST_INCR ] ; then
        INCRBASEDIR=$FULLBACKUPDIR/$LATEST_FULL
      else
        INCRBASEDIR=$LATEST_INCR
      fi

      echo "Running new incremental backup using $INCRBASEDIR as base."
      innobackupex --defaults-file=$MYCNF $USEROPTIONS $rsyncTables $compress $compression_threads --incremental $TMPINCRDIR --incremental-basedir $INCRBASEDIR 2>&1 | tee $TMPFILE
    fi
  fi
  if [ -z "$(tail -1 $TMPFILE | grep 'completed OK!')" ] ; then
    echo "$INNOBACKUPEX failed:"; echo
    echo "---------- ERROR OUTPUT from $INNOBACKUPEX ----------"
    cat $TMPFILE
    exit 1
  fi
  THISBACKUP="$(awk -- "/Backup created in directory/ { split( \$0, p, \"'\" ) ; print p[2] }" $TMPFILE)"

  echo "Databases backed up successfully to: $THISBACKUP"
  echo

  # rsync just the new or modified backup files
  if [ ! -z "$SERVERBACKUPHOST" ]; then
    echo "Adding ssh-key of remote host to known_hosts"
    if [ -f ~/.ssh/known_hosts ]; then
      ssh-keygen -R $SERVERBACKUPHOST 2>&1 | tee $rsyncLog
    fi
    ssh-keyscan $SERVERBACKUPHOST >> ~/.ssh/known_hosts  2>&1 | tee $rsyncLog
    echo "Rsyncing files to remote host"
    /usr/bin/rsync -rhtPpv --rsync-path=rsync --progress $BACKUPDIR/* -e ssh xtrabackup@$SERVERBACKUPHOST:$SERVERBACKUPDIR 2>&1 | tee $rsyncLog

    # Check if the rsync succeeded or failed
    if ! grep -q "rsync error: " $rsyncLog; then
      echo "Rsync to remote host completed OK"
    else
      echo "Rsync to remote host FAILED"
      exit 1
    fi
  fi
}
function cleanup_backup()
{
  # Cleanup
  if [ "$SKIPCLEANUP" == false ] ; then
    if [ "$BACKUPTIME" != true ]; then
      echo "----------------------------"
      echo "Cleanup. Keeping only $KEEP full backups and its incrementals."
      AGE=$(($FULLBACKUPLIFE * $KEEP / 60))
      find $FULLBACKUPDIR -maxdepth 1 -type d -mmin +$AGE -execdir echo "removing: "$FULLBACKUPDIR/{} \; -execdir rm -rf $FULLBACKUPDIR/{} \; -execdir echo "removing: "$INCRBACKUPDIR/{} \; -execdir rm -rf $INCRBACKUPDIR/{} \;

      echo
      echo "completed: $(date)"
      exit 0
    else
      echo "----------------------------"
      echo "Cleanup. Keeping only $KEEP full backups and its incrementals."

      NUMBER_OF_FULL="$(( $(find $FULLBACKUPDIR -maxdepth 1 -type d -print| wc -l) - 1))"
      FULL_TO_DELETE="$(( $NUMBER_OF_FULL - $KEEP ))"
      echo "Found $NUMBER_OF_FULL full backups and $KEEP should be kept. This $FULL_TO_DELETE will be deleted."
      if [ $FULL_TO_DELETE -gt 0 ] ; then
        cd $INCRBACKUPDIR
        ls -t $FULLBACKUPDIR | tail -n -$FULL_TO_DELETE | xargs -d '\n' rm -rf
        cd $FULLBACKUPDIR
        ls -t | tail -n -$FULL_TO_DELETE | xargs -d '\n' rm -rf
      else
        echo "There are less full backups than required, not deleting anything."
      fi
    fi
  else
    echo "----------------------------"
    echo "-s parameter passed. Cleanup was not triggered"
  fi
}

while getopts ":sfhc" opt; do
  case $opt in
    s)
      echo "Cleanup will be skipped" >&2
      SKIPCLEANUP="true"
    ;;
    c)
      echo "Cleanup backups" >&2
      cleanup_backup
      exit 0
    ;;
    f)
      echo "Full backup will be force triggered"
      FORCEFULL="true"
    ;;
    h)
      usage
      exit 0
    ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      usage
      exit 1
    ;;
  esac
done

prerequisites
backup
cleanup_backup