#!/bin/bash
armb_ver='4_090617'

log_file=/var/log/${0##*/}.log
lock_file=/tmp/${0##*/}.lock

dumps_dir='/var/backups/mysql/daily_from_vs05'
mysql_data_dir='/var/lib/mysql'

db_name=''
db_user=''
db_pass=''
db_connection_host=''

mysql_bin="`which mysql` -u root -h localhost -p`cat /root/.mysql`"
latest_dump=`find $dumps_dir -maxdepth 1 -type f -name "*.snapshot.sql.*" -printf '%T@ %p\n' | sort -n | tail -1 | cut -d' ' -f 2`

function update_date() {
    test -f $latest_dump || { echo "`date '+%Y/%m/%d:%H:%M:%S'` Error. File $latest_dump doesn't exist!"; return 1; }
    latest_date=`date '+%Y-%m-%d %H:%M:%S' -r $latest_dump`
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Starting update date in table."
    $mysql_bin -B -N -e "UPDATE db_date SET mydate=\"${latest_date}\";" $db_name && \
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Update date in table finished." || \
    { echo "`date '+%Y/%m/%d:%H:%M:%S'` Error. Something go wrong on update date in table."; return 1; }
}

function init_db() {
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Starting function init_db"
    $mysql_bin -B -N -e "USE $db_name; CREATE TABLE db_date (mydate DATETIME); INSERT INTO db_date SET mydate=NOW();" && \
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Table \"db_date\" created in $db_name. Starting function update_date" && \
    update_date 
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Create privileges"
    $mysql_bin -B -N -e "GRANT ALL PRIVILEGES ON $db_name.* TO db_user@$db_connection_host IDENTIFIED BY \"$db_pass\";"
}

function stop_mysql() {
        echo "`date '+%Y/%m/%d:%H:%M:%S'` Starting function stop_mysql"
        /etc/init.d/mysql stop
        if pgrep -x mysqld >/dev/null
                then 
                        echo "`date '+%Y/%m/%d:%H:%M:%S'` Error. Something go wrong, Mysql process still running!!!"
                        return 1
        fi
}

function start_mysql() {
        echo "`date '+%Y/%m/%d:%H:%M:%S'` Starting function start_mysql"
        /etc/init.d/mysql start
        if ! pgrep -x mysqld >/dev/null
                then 
                        echo "`date '+%Y/%m/%d:%H:%M:%S'` Error. Something go wrong, Mysql process don't start!!!"
                        return 1
        fi
}

function extract_dump() {
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Extract dump-file $latest_dump to $mysql_data_dir"
    test -d $mysql_data_dir || mkdir -p $mysql_data_dir
    tar -xvzf $latest_dump -C $mysql_data_dir && \
    echo "`date '+%Y/%m/%d:%H:%M:%S'` Extract dump-file $latest_dump to $mysql_data_dir finished" || \
    { echo "`date '+%Y/%m/%d:%H:%M:%S'` Error. Something go wrong on extract dump-file $latest_dump to $mysql_data_dir!"; return 1; }
}

function change_datadir() {
        echo "`date '+%Y/%m/%d:%H:%M:%S'` Starting function move_datadir"
        which innobackupex > /dev/null 2>&1 || { echo "`date '+%Y/%m/%d:%H:%M:%S'`Error. No innobackupex installed!"; return 1; }
        stop_mysql && \
        test -d $mysql_data_dir -a "$mysql_data_dir" != '/' && { 
            echo "`date '+%Y/%m/%d:%H:%M:%S'` Remove $mysql_data_dir"
            chattr -i $mysql_data_dir/my.cnf 
            rm -rf $mysql_data_dir && \
            extract_dump && \
            chattr -i $mysql_data_dir/my.cnf && \
            chown -R mysql:mysql $mysql_data_dir 
        } && \
        start_mysql
}

which flock > /dev/null || { echo "No flock installed. You need to install flock first."; exit 1;}
{
    flock -n 9 || { echo "Another copy of ${0##*/} is still running on $myhostname. Lock file $lock_file locked.\n"; exit 1; }
        test -f $log_file && mv $log_file $log_file.1
        {
                echo "`date '+%Y/%m/%d:%H:%M:%S'` Importing dump-file $latest_dump"

                change_datadir && \
                init_db
                echo "`date '+%Y/%m/%d:%H:%M:%S'` Importing dump-file $latest_dump finished."
        } >> $log_file  2>> >(tee -a $log_file >&2)
} 9> $lock_file

test -f $lock_file && rm -f $lock_file