#!/bin/bash
#%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%#
# MySQL database backup script               [Thomas Lange <code@nerdmind.de>] #
#%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%#
#                                                                              #
# This database backup script goes through each database (except the excluded  #
# databases in DATABASE_EXCLUDED) and creates a bzip2 compressed backup file.  #
#                                                                              #
# OPTION [-q]: Enable quiet mode for use in crontab.                           #
#                                                                              #
#%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%#

#===============================================================================
# Parsing command-line arguments with the getopts shell builtin
#===============================================================================
while getopts :q option
do
	case $option in
		q) ARGUMENT_QUIETMODE=true ;;
	esac
done

#===============================================================================
# Define database login credentials and excluded databases
#===============================================================================
DATABASE_USERNAME="InsertYourUsernameHere"
DATABASE_PASSWORD="InsertYourPasswordHere"
DATABASE_EXCLUDED="(Database|mysql|information_schema|performance_schema)"

#===============================================================================
# Define backup directories and target filename
#===============================================================================
DIRECTORY_ROOT="/mnt/data/backups/databases/"
DIRECTORY_PATH="$(date +%Y-%m-%d-%Hh%Mm)/"
DIRECTORY_FILE="${DIRECTORY_ROOT}${DIRECTORY_PATH}%s.sql.bz2"

#===============================================================================
# Delete old backups in backup root directory
#===============================================================================
if [ -d "${DIRECTORY_ROOT}" ]; then
	find "${DIRECTORY_ROOT}"* -maxdepth 0 -type d -mtime +90 -exec rm --recursive {} \;
else
	mkdir -p "${DIRECTORY_ROOT}"
fi

#===============================================================================
# Create backup path directory if not exists
#===============================================================================
if [ ! -d "${DIRECTORY_ROOT}${DIRECTORY_PATH}" ]; then
	mkdir "${DIRECTORY_ROOT}${DIRECTORY_PATH}"
fi

#===============================================================================
# Fetch all database names from local MySQL server
#===============================================================================
DATABASES=$(mysql --user="${DATABASE_USERNAME}" --password="${DATABASE_PASSWORD}" --execute="SHOW DATABASES;" | grep -Ev "${DATABASE_EXCLUDED}")

#===============================================================================
# Loop through all database names and create compressed database backup
#===============================================================================
for database in ${DATABASES}; do
	[ ! $ARGUMENT_QUIETMODE ] && echo "[INFO] Creating compressed backup for database ${database} [...]"
	mysqldump --lock-all-tables --user="${DATABASE_USERNAME}" --password="${DATABASE_PASSWORD}" "${database}" | bzip2 > $(printf "${DIRECTORY_FILE}" "${database}")
done