xtrabackup.sh

#!/bin/bash

die () {
	echo -e 1>&2 "$@"
	exit 1
}

fail () {
	die "...FAILED! See $LOG_FILE for details - aborting.\n"
}

INNOBACKUPEX=$(which innobackupex)
[ -f "$INNOBACKUPEX" ] || die "innobackupex script not found - please ensure xtrabackup is installed before proceeding."


##CONTAINER=$(export | sed -nr "/ENV_MYSQL_DATABASE/{s/^.+ -x (.+)_ENV.+/\1/p;q}")
##DB_PORT=$(export | sed -nr "/-x ${CONTAINER}_PORT_[[:digit:]]+_TCP_PORT/{s/^.+ -x (.+)=.+/\1/p}")
##DB_ADDR="${CONTAINER}_PORT_${!DB_PORT}_TCP_ADDR"
##DB_NAME="${CONTAINER}_ENV_MYSQL_DATABASE"
##DB_PASS="${CONTAINER}_ENV_MYSQL_ROOT_PASSWORD"

CONFIG_FILE=/backups/.xtrabackup.config

if [ -f $CONFIG_FILE ]; then
	echo -e "Loading configuration from $CONFIG_FILE."
	source $CONFIG_FILE
else
cat << EOF > $CONFIG_FILE
MYSQL_HOST=mysql-host
MYSQL_PORT=3306
MYSQL_USER="$(whoami)"
MYSQL_PASS=
MYSQL_DATA_DIR=/var/lib/mysql/
BACKUPS_DIRECTORY=/backups/mysql-backups
MAX_BACKUP_CHAINS=8
EOF

	die "Configuration has been initialised in $CONFIG_FILE. \nPlease make sure all settings are correctly defined/customised - aborting."
fi

[ -d $MYSQL_DATA_DIR ] || die "Please ensure the MYSQL_DATA_DIR setting in the configuration file points to the directory containing the MySQL databases."
[ -n "$MYSQL_USER" -a -n "$MYSQL_PASS" ] || die "Please ensure MySQL username and password are properly set in the configuration file."

FULLS_DIRECTORY=$BACKUPS_DIRECTORY/full
INCREMENTALS_DIRECTORY=$BACKUPS_DIRECTORY/incr
LOGS="/backups/logs"


mkdir -vp $FULLS_DIRECTORY
mkdir -vp $INCREMENTALS_DIRECTORY
mkdir -vp $LOGS

IONICE=$(which ionice)

if [ -n "$IONICE" ]; then
	IONICE_COMMAND="$IONICE -c2 -n7"
fi

INNOBACKUPEX_COMMAND="$(which nice) -n 15 $IONICE_COMMAND $INNOBACKUPEX"
RSYNC_COMMAND="$(which nice) -n 15 $IONICE_COMMAND  $(which rsync)"

full_backup () {
	$INNOBACKUPEX_COMMAND --slave-info --host="$MYSQL_HOST" --port=$MYSQL_PORT --user="$MYSQL_USER" --password="$MYSQL_PASS" "$FULLS_DIRECTORY"

	NEW_BACKUP_DIR=$(find $FULLS_DIRECTORY -mindepth 1 -maxdepth 1 -type d -exec ls -dt {} \+ | head -1)

	echo $NEW_BACKUP_DIR > $NEW_BACKUP_DIR/backup.chain
}

incremental_backup () {
	LAST_BACKUP=${LAST_CHECKPOINTS%/xtrabackup_checkpoints}

	$INNOBACKUPEX_COMMAND --slave-info --host="$MYSQL_HOST" --port=$MYSQL_PORT --user="$MYSQL_USER" --password="$MYSQL_PASS" --incremental --incremental-basedir="$LAST_BACKUP" "$INCREMENTALS_DIRECTORY"

	NEW_BACKUP_DIR=$(find $INCREMENTALS_DIRECTORY -mindepth 1 -maxdepth 1 -type d -exec ls -dt {} \+ | head -1)
	cp $LAST_BACKUP/backup.chain $NEW_BACKUP_DIR/
	echo $NEW_BACKUP_DIR >> $NEW_BACKUP_DIR/backup.chain
}


#
# Call before hooks
#
if [ -d "/hooks" ] && ls /hooks/*.before 1> /dev/null 2>&1; then
  for hookfile in /hooks/*.before; do
    eval $hookfile
    echo "Called hook $hookfile"
  done
fi


if [ "$1" = "full" ]; then
	full_backup
elif [ "$1" = "incr" ]; then
	LAST_CHECKPOINTS=$(find $BACKUPS_DIRECTORY -mindepth 3 -maxdepth 3 -type f -name xtrabackup_checkpoints -exec ls -dt {} \+ | head -1)
	
	if [[ -f $LAST_CHECKPOINTS ]]; then
		incremental_backup
	else
		full_backup
	fi
elif [ "$1" = "list" ]; then
	if [[ -d $FULLS_DIRECTORY ]]; then
		BACKUP_CHAINS=$(ls $FULLS_DIRECTORY | wc -l)
	else
		BACKUP_CHAINS=0
	fi
		
	if [[ $BACKUP_CHAINS -gt 0 ]]; then
		echo -e "Available backup chains (from oldest to latest):\n"

		for FULL_BACKUP in `ls $FULLS_DIRECTORY -tr`; do
			let COUNTER=COUNTER+1

			echo "Backup chain $COUNTER:"
			echo -e "\tFull:        $FULL_BACKUP"

			if [[ $(ls $INCREMENTALS_DIRECTORY | wc -l) -gt 0 ]]; then
				grep -l $FULL_BACKUP $INCREMENTALS_DIRECTORY/**/backup.chain | \
				while read INCREMENTAL; 
				do 
					BACKUP_DATE=${INCREMENTAL%/backup.chain}
					echo -e "\tIncremental: ${BACKUP_DATE##*/}"
				done
			fi
		done
		
		LATEST_BACKUP=$(find $BACKUPS_DIRECTORY -mindepth 2 -maxdepth 2 -type d -exec ls -dt {} \+ | head -1)
		
		[[ "$LATEST_BACKUP" == *full* ]] && IS_FULL=1 || IS_FULL=0

		BACKUP_DATE=${LATEST_BACKUP##*/}

		if [[ "$LATEST_BACKUP" == *full* ]]
		then
		  echo -e "\nLatest backup available:\n\tFull: $BACKUP_DATE"
		else
		  echo -e "\nLatest backup available:\n\tIncremental: $BACKUP_DATE"
		fi
		
		exit 1
	else
		die "No backup chains available in the backup directory specified in the configuration ($BACKUPS_DIRECTORY)"
	fi
elif [ "$1" = "restore" ]; then
	([ -n "$2" ] && [ -n "$3" ]) || die "Missing arguments. Please run as: \n\t$0 restore <timestamp> <destination folder>\nTo see the list of the available backups, run:\n\t$0 list"
		
	BACKUP_TIMESTAMP="$2"
	DESTINATION="$3"
	BACKUP=`find $BACKUPS_DIRECTORY -mindepth 2 -maxdepth 2 -type d -name $BACKUP_TIMESTAMP -exec ls -dt {} \+ | head -1`
	LOG_FILE="$LOGS/restore-$BACKUP_TIMESTAMP.log"
	
	echo "" > $LOG_FILE
	
	(mkdir -vp $DESTINATION) || die "Could not access destination folder $3 - aborting"
	
	if [[ -d "$BACKUP" ]]; then
		echo -e "!! About to restore MySQL backup taken on $BACKUP_TIMESTAMP to $DESTINATION !!\n"
		
		if [[ "$BACKUP" == *full* ]]; then
			echo "- Restore of full backup taken on $BACKUP_TIMESTAMP"

			echo "Copying data files to destination..."
			$RSYNC_COMMAND --quiet -ah --delete $BACKUP/ $DESTINATION &>> $LOG_FILE || fail
			echo -e "...done.\n"
		
			echo "Preparing the destination for use with MySQL..."
			$INNOBACKUPEX_COMMAND --apply-log --ibbackup=xtrabackup_51 $DESTINATION  &>> $LOG_FILE || fail
			echo -e "...done.\n"
		else
			XTRABACKUP=$(which xtrabackup)
			
      [ -f "$XTRABACKUP" ] || die "xtrabackup executable not found - this is required in order to restore from incrementals. Ensure xtrabackup is installed properly - aborting."

      XTRABACKUP_COMMAND="$(which nice) -n 15 $IONICE_COMMAND $XTRABACKUP"
		
			FULL_BACKUP=$(cat $BACKUP/backup.chain | head -1)
		
			echo "- Restore of base backup from $FULL_BACKUP"

			echo "Copying data files to destination..."
			$RSYNC_COMMAND --quiet -ah --delete $FULL_BACKUP/ $DESTINATION  &>> $LOG_FILE || fail
			echo -e "...done.\n"

			echo "Preparing the base backup in the destination..."
			#$XTRABACKUP_COMMAND --prepare --apply-log-only --target-dir=$DESTINATION &>> $LOG_FILE || fail
      $INNOBACKUPEX_COMMAND --apply-log --redo-only $DESTINATION &>> $LOG_FILE || fail
			echo -e "...done.\n"
		
			for INCREMENTAL in $(cat $BACKUP/backup.chain | tail -n +2); do
				echo -e "Applying incremental from $INCREMENTAL...\n"
				#$XTRABACKUP_COMMAND  --prepare --apply-log-only --target-dir=$DESTINATION --incremental-dir=$INCREMENTAL  &>> $LOG_FILE || fail
        $INNOBACKUPEX_COMMAND --apply-log --redo-only $DESTINATION --incremental-dir=$INCREMENTAL &>> $LOG_FILE || fail
				echo -e "...done.\n"
			done

			echo "Finalising the destination..."
			#$XTRABACKUP_COMMAND --prepare --target-dir=$DESTINATION  &>> $LOG_FILE || fail
      $INNOBACKUPEX_COMMAND --apply-log  $DESTINATION &>> $LOG_FILE || fail
			echo -e "...done.\n"
		fi
		
		rm $LOG_FILE # no errors, no need to keep it
		
		echo -e "The destination is ready. All you need to do now is:
	- ensure the MySQL user owns the destination directory, e.g.: chown -R mysql:mysql $DESTINATION
	- stop MySQL server
	- replace the content of the MySQL datadir (usually /var/lib/mysql) with the content of $DESTINATION
	- start MySQL server again"
	else
		die "Backup not found. To see the list of the available backups, run: $0 list"
	fi
else
  die "Backup type not specified. Please run: as $0 [incr|full|list|restore]"
fi

BACKUP_CHAINS=`ls $FULLS_DIRECTORY | wc -l`

if [[ $BACKUP_CHAINS -gt $MAX_BACKUP_CHAINS ]]; then
	CHAINS_TO_DELETE=$(expr $BACKUP_CHAINS - $MAX_BACKUP_CHAINS)
	
	for FULL_BACKUP in `ls $FULLS_DIRECTORY -t |  tail -n $CHAINS_TO_DELETE`; do
		grep -l $FULLS_DIRECTORY/$FULL_BACKUP $INCREMENTALS_DIRECTORY/**/backup.chain | while read incremental; do rm -rf "${incremental%/backup.chain}"; done
		$IONICE_COMMAND rm -rf $FULLS_DIRECTORY/$FULL_BACKUP
	done
fi

unset MYSQL_USER
unset MYSQL_PASS

#
# Call after hooks
#
if [ -d "/hooks" ] && ls /hooks/*.after 1> /dev/null 2>&1; then
  for hookfile in /hooks/*.after; do
    echo "===> Calling hook ${hookfile}... "
    eval $hookfile
    echo "===> Calling hook ${hookfile}... DONE"
  done

  echo "===> All hooks processed, finished."
else
  echo "===> No hooks found, finished."
fi