automydumper

#!/bin/bash

export PATH="$PATH:/bin:/usr/bin"

# Defaults
backup_root_dir='/var/backups/automydumper'
backup_dir_format='+%F'
pre_dir='/usr/share/automydumper/pre.d'
post_dir='/usr/share/automydumper/post.d'
compress=1
keep=3
mysql_user='root'
mysql_password=''
mysql_host='localhost'
mysql_socket=
threads=4
mydumper_opts='--less-locking --use-savepoints'
enabled=1
mail_rcpts=''
mail_from="automydumper@${HOSTNAME}"

# Override defaults if config file is present
if [ -f '/etc/automydumper.cfg' ]; then
    source /etc/automydumper.cfg
fi

backup_dir_format="${backup_dir_format/ /}"

formatted_date="$(date ${backup_dir_format})"

backup_dir="${backup_root_dir}/${formatted_date}"

version="1.1.0"
# What versions of Mydumper do we support?
mydumper_versions='0.9'

mydumper_opts="${mydumper_opts} --triggers --events --routines -o ${backup_dir} -v 3 --threads ${threads}"

# Compression support
[ $compress -eq 1 ] && mydumper_opts="$mydumper_opts --compress"


options=$(getopt -o h --long help -- "$@")
[ $? -eq 0 ] || {
    echo "Incorrect options provided"
    exit 1
}
eval set -- "$options"
while true; do
    case "$1" in
    --help|-h)
        echo ""
        echo "Automydumper ${version}"
        echo ""
        exit
        ;;
    --)
        shift
        break
        ;;
    esac
    shift
done

function mysql_credentials()
{
    echo -n "--user=${mysql_user} "

    if [ ! -z "${mysql_password}" ]; then
        echo -n "--password=${mysql_password} "
    fi

    echo "${mysql_host}" | grep -E "(localhost|127.0.0.1)" > /dev/null
    if [ $? -eq 0 ]; then
        [ ${mysql_socket} ] && echo -n "--socket=${mysql_socket}" || echo -n ''
    else
        echo -n "--host=${mysql_host}"
    fi
}

function check_mysql()
{
    which mysql > /dev/null
    if [ $? -ne 0 ]; then
        write_state "critical" "MySQL client not installed."
        exit 1
    fi
}

function check_mydumper()
{
    which mydumper > /dev/null
    if [ $? -ne 0 ]; then
        write_state "critical" "Mydumper not installed."
        exit 1
    fi
}

function check_mysql_connection()
{
    mysql $(mysql_credentials) -e 'select VERSION()' > /dev/null
    if [ $? -ne 0 ]; then
        write_state "critical" 'Wrong MySQL credentials or hostname/socket.'
        exit 1
    fi
}

function check_mydumper_version()
{
    for mydumper_version in $mydumper_versions; do
        mydumper --version | grep -i "mydumper $mydumper_version" > /dev/null && return 0
    done
    write_state "critical" "Unsupported version of Mydumper found."
    echo "Supported versions: $mydumper_versions"
    exit 1
}

function check_backup_root_dir()
{
    if [ "$(basename ${backup_root_dir})" != "automydumper" ]; then
        write_state "critical" "Backup_root_dir top directory should be 'automydumper'"
        exit 1
    fi
}

function create_directories()
{
    mkdir -p $(dirname "${backup_dir}") "${pre_dir}" "${post_dir}"
}

function cleanup_backups()
{

    if [ ${keep} -eq 0 ]; then
        echo -e "Cleanup of old backups disabled because of keep=0\n"
        return
    fi

    while [ "$(find "${backup_root_dir}" -type f -name "metadata" | wc -l)" -gt "${keep}" ]; do
        oldest=$(find "${backup_root_dir}" -type f -name "metadata" -printf '%Cs %h\n' | sort | head -n 1 | awk '{ print $2}')
        echo "Deleting ${oldest}"
        rm -rf "${oldest}"
    done
    echo ""

}

function write_state()
{
    mkdir -p "/var/lib/automydumper"
    cat > /var/lib/automydumper/state << EOF
status="$1"
description="$2"
started="${curdate} ${curtime}"
EOF
    chmod +r /var/lib/automydumper/state
    echo $2
    echo ""
}

function run_pre_commands()
{
    for cmd in $(find ${pre_dir} -type f -executable); do
        echo "Executing pre command: '${cmd}'"
        ${cmd} || ( write_state "critical" "Pre-backup command failed."; exit 1)
        echo ""
    done
}

function run_post_commands()
{
    for cmd in $(find ${post_dir} -type f -executable); do
        echo "Executing post command: '${cmd}'"
        ${cmd} || ( write_state "critical" "Post-backup command failed."; exit 1)
        echo ""
    done
}

function mail_report()
{
    if [ ! -z "${mail_rcpts}" ]; then
        echo "Sending mail report to '${mail_rcpts}' from '${mail_from}'"
        grep "^${formatted_date} " "${log_file}" | mailx -s "Backup for $(hostname) ${1}" -r "${mail_from}" "${mail_rcpts}"
    else
        echo -e "Not configured to send a mail report.\n"
    fi
    echo ""
}

function verify_backups()
{
    if grep "^${formatted_date} " "${log_file}" | grep WARNING > /dev/null; then
        write_state "warning" "Backup completed with warnings."
        mail_report 'Warning'
    else
        write_state "ok" "Backup completed successfully."
        echo -e "Saved to ${backup_dir}.\n"
        mail_report 'OK'
    fi
}

function symlink_latest()
{
    rm -f "${backup_root_dir}/latest"
    ln -sf "${backup_dir}" "${backup_root_dir}/latest"
}

# Stop the script when it's disabled by the user.
if [ $enabled -eq 0 ]; then
    echo "Script is disabled. Enable by removing enabled=0 from /etc/default/automydumper. Quitting."
    exit 0
fi

trap "{ write_state critical 'Backup failed.' ; mail_report 'failed'; exit 255; }" ERR

exec > >(sed "/^\s*$/d;s#^#automydumper #" | tee -i >(exec logger -i))
exec 2>&1

check_backup_root_dir
check_mysql
check_mydumper
check_mydumper_version
check_mysql_connection
create_directories

echo -e "\nAutomydumper ${version} using $(mydumper --version | grep -i "mydumper")\n"

mydumper_opts="${mydumper_opts} $(mysql_credentials)"

# Run pre_command if it is defined
run_pre_commands

# Remove old backup first
rm -rf "${backup_dir}"

mydumper ${mydumper_opts}
if [ $? -ne 0 ]; then
    echo "Backup failed."
    rm -rf "${backup_dir}"
    exit 1
fi

symlink_latest

# Run post_command if it is defined
run_post_commands

cleanup_backups

verify_backups