#!/bin/bash

if [ $# -lt 2 ]; then
        echo "Usage: mysql-repl <master hostname> <slave hostname> ..." 1>&2
        echo
        exit 1
fi

RSYNC_PORT=873

MASTER=$1
shift
SLAVES=$@
REMOTEPATH=/usr/sbin:/usr/bin:/sbin:/bin:/www/mysql/bin:/www/mysql-backup/bin
TMPFILE=/tmp/mysql-repl.$$


function ask_again {
        read -p "Try again? [Y/n]" ANSWER
        [ "$ANSWER" != "N" -a "$ANSWER" != "n" ] || exit 1
}
function f_ask_again {
        echo Failed
        echo
        ask_again
}
function error_output {
	echo "Error output follows:"
	cat $TMPFILE
	rm $TMPFILE
}


echo
echo "Setting up MySQL replication from $MASTER to:"
for SLAVE in $SLAVES; do
	echo -e "\t$SLAVE"
done
read -p "Do you want to continue? [y/N] " ANSWER
[ "$ANSWER" != "Y" -a "$ANSWER" != "y" ] && exit 1



touch $TMPFILE
echo
echo "Note that You may see the progres watching tempfile $TMPFILE."
echo "( $ tail -f $TMPFILE )"
read -p "Pres ENTER to continue"



echo
echo "Checking ssh to given hosts:"
for host in $MASTER $SLAVES; do
        echo -n "        $host ... "
        if ssh root@$host true 2> $TMPFILE; then
                echo OK
        else
                echo Failed
                echo
                cat $TMPFILE
                exit 1
        fi
done



OK=0
echo
while [ $OK -le $# ]; do
        OK=0
        echo "Checking szn-mysql5-backup and rsync:"
        for host in $MASTER $SLAVES; do
                echo -n "        $host: "
                if [ "$(ssh root@$host dpkg -l szn-mysql5-backup rsync | grep -c ^ii)" = "2" ]; then
                        echo OK
                        OK=$((OK+1))
                else
                        echo Failed
                        echo "Trying to install szn-mysql5-backup and rsync on $host:"
                        if ssh root@$host -t "apt-get install szn-mysql5-backup rsync"; then
                                echo
                                echo "Instalation complete."
                                OK=$((OK+1))
                        else
                                echo
                                echo "Instalation failed."
                                echo
                                ask_again
                        fi
                fi
        done
done



OK=0
while [ $OK = 0 ]; do
        echo
        echo -n "Creating backup on $MASTER: "
        ssh root@$MASTER -t PATH=$REMOTEPATH mysql5-backup backup_innodb > $TMPFILE 2>&1
        if tail -n 5 $TMPFILE | grep -q "innobackup: innobackup completed OK!"; then
                echo OK
                OK=1
        else
                echo Failed
                echo
		error_output
                echo
                ask_again
        fi
done



OK=0
echo
echo "Parsing backup output:"

echo -en "\t* backup dir: "
read BACKUPDIR <<< "$(grep "Backup created in directory" $TMPFILE | sed -r "s/^.*directory '(.*)'.*$/\1/")"
echo -n "$BACKUPDIR ... "
while ! ssh root@$MASTER "test -d $BACKUPDIR"; do
	echo Failed
	echo
        read -p "Entrer the backup dir > " BACKUPDIR
	echo -en "\t* backup dir: $BACKUPDIR ... "
done
echo OK
_BACKUPDIR=`echo $BACKUPDIR | sed s/\\\\//\\\\\\\\\\\\//g`

echo
echo -en "\t* last binlog position:"
read LOGFILE LOGPOS <<< "$(grep "MySQL binlog position" $TMPFILE | sed -r "s/^.*filename '([^']+)', position ([0-9]+).*$/\1 \2/")"
echo -n "$LOGFILE:$LOGPOS ... "
while [ -z $LOGFILE ] || ! ssh root@$MASTER "test -f /www/mysql/data/$LOGFILE" 2> /dev/null; do
	echo Failed
	echo
	read -p "Insert correct binlog file > " LOGFILE
	echo -en "\t* last binlog position: $LOGFILE:$LOGPOS ... "
done
while [ -z $LOGPOS ]; do
	echo Failed
	echo
	read -p "Insert correct binlog position > " LOGPOS
	echo -en "\t* last binlog position: $LOGFILE:$LOGPOS ... "
done
echo OK



OK=0
while [ $OK = 0 ]; do
        echo
	echo -n "Starting rsync server on $MASTER ... "
	ssh root@$MASTER "cat > .mysql-repl.rsyncd.conf" <<EOF
log file = /dev/stderr
pid file = /var/run/mysql-repl.rsyncd.pid
uid = 0
gid = 0
port = 873
read only = yes
use chroot = yes
list = yes
[mysql-repl]
path = $BACKUPDIR
EOF
	if ssh root@$MASTER "rsync --daemon --config=.mysql-repl.rsyncd.conf" &> $TMPFILE; then
		echo OK
		OK=1
	else
		echo Failed
		ssh root@$MASTER rm -f .mysql-repl.rsyncd.conf &>> $TMPFILE
                echo
		error_output
                echo
                ask_again
        fi
done



sleep 5



OK=0
while [ $OK -lt $# ]; do
	OK=0
	echo
	echo "Syncing backup files from master to slaves:"
	for SLAVE in $SLAVES; do
		echo -en "\t* forking rsync on $SLAVE ... "
		if ssh root@$SLAVE "rsync -a $MASTER::mysql-repl/ $BACKUPDIR/" && touch $TMPFILE.$SLAVE.stamp & then
			echo OK
		else
			echo Failed
		fi
	done
	echo -n "Waiting ... "; wait; echo done

	echo
	echo "Checking rsync results:"
	for SLAVE in $SLAVES; do
		echo -en "\t* checking result of rsync on $SLAVE ... "
		if rm $TMPFILE.$SLAVE.stamp 2> /dev/null; then
			echo OK
			OK=$((OK+1))
		else
			echo Failed
		fi
	done
done



echo
echo -n "Removing backup files from master ... "
if ssh root@$MASTER "rm -r $BACKUPDIR" &> $TMPFILE; then
	echo OK
else
	echo Failed
	echo
	error_output
	echo
	echo Please remove $BACKUPDIR on $MASTER.
	read -p "Pres ENTER to continue"
fi



echo
echo -n "Killing rsync server on $MASTER ... "
if ssh root@$MASTER "kill \$(</var/run/mysql-repl.rsyncd.pid)" &> $TMPFILE; then
	echo OK
else
	echo Failed
	echo
	error_output
	echo
	echo Please kill the rsync server.
	read -p "Pres ENTER to continue"
fi



OK=0
echo
while [ $OK = 0 ]; do
        read -sp "Insert MySQL replication password > " PASS1
        echo
        read -sp "Repeat MySQL replication password > " PASS2
        echo
        if [ $PASS1 != $PASS2 ]; then
                echo "Passwords do not match."
        elif [ -z "$PASS1" ]; then
                echo "Password is empty"
        else
                OK=1
        fi
done



for SLAVE in $SLAVES; do
	echo
	FIRST=1
	while ssh root@$SLAVE mysqladmin ping > /dev/null 2>&1; do
		echo "Slave MySQL server is running"
		if [ $FIRST = 1 ]; then
			echo "Going to stop the slave MySQL server ($SLAVE)."
			read -p "Pres ENTER to continue ... "
			FIRST=0
		fi
		echo -n "Stoping slave mysqld on $SLAVE: "
		if ssh root@$SLAVE mysqladmin shutdown > /dev/null 2>&1; then
			echo OK
		else
			f_ask_again
		fi
	done



	OK=0
	ssh root@$SLAVE "rm -rf /www/mysql/data/master.info"
	while [ $OK = 0 ]; do
		echo
		echo -n "Applying log on $SLAVE ... "
		ssh root@$SLAVE PATH=$REMOTEPATH innobackup --apply-log $BACKUPDIR/backup-my.cnf $BACKUPDIR/ > $TMPFILE 2>&1
		if tail -n 5 $TMPFILE | grep -q "innobackup: innobackup completed OK!"; then
			echo OK
			OK=1
		else
			echo Failed
			echo
			error_output
			echo
			ask_again
		fi
	done
	ssh root@$SLAVE "rm -rf /www/mysql/data/*"



	echo -n "Tunning $BACKUPDIR/backup-my.cnf ... "
	if ssh root@$SLAVE "sed -i 's/$_BACKUPDIR/\/www\/mysql\/data/' $BACKUPDIR/backup-my.cnf"; then
		echo OK
	else
		echo Failed
		echo
		read -p "Fix the file manually and press ENTER to continue. "
	fi



	echo
	echo -n "Moving backup on $SLAVE ... "
	if ssh root@$SLAVE "rm -rf /www/mysql/data.repl_{old,new}; chown -R mysql:mysql $BACKUPDIR && mv $BACKUPDIR /www/mysql/data.repl_new && mv /www/mysql/data /www/mysql/data.repl_old && mv /www/mysql/data.repl_new /www/mysql/data" > $TMPFILE 2>&1; then
		echo OK
		echo -n "Removing old data files from $SLAVE ... "
		ssh root@$SLAVE "rm -rf /www/mysql/data.repl_old" && echo OK || echo Failed
	else
		echo Failed
		echo
		error_output
		echo
		echo "Please move the data dir from $BACKUPDIR to /www/mysql/data manually."
		read -p "Pres ENTER to continue ... "
	fi



	ssh root@$SLAVE "chown -R mysql:mysql /www/mysql/data/"



	OK=0
	echo
	echo -n "Fetching config file from master ... "
	if rsync root@$MASTER:/etc/mysql/my.cnf $TMPFILE 2> /dev/null; then
		echo OK
		echo -n "Parsing server-id: "
		MASTERID=`grep ^server-id $TMPFILE | sed -r 's/.*=\\s+(\\S+)\\s*/\\1/'`
		if [ -n "$MASTERID" ]; then
			echo "OK ($MASTERID)"
			read -p "Insert slave server-id (default $((MASTERID+1))) > " SLAVEID
			test -z $SLAVEID && SLAVEID=$((MASTERID+1))
			echo -n "Updating slave config file ... "
			if sed -r -i "s/^(server-id\s*=\s*)(\S+)\s*/\1$SLAVEID/" $TMPFILE; then
				echo OK
				echo -n "Syncing config file to $SLAVE ... "
				if rsync $TMPFILE root@$SLAVE:/etc/mysql/my.cnf 2> /dev/null; then
					echo OK
					OK=1
				else
					echo Failed
				fi
			else
				echo Failed
			fi
		else
			echo Failed
			rm $TMPFILE
		fi
	else
		echo Failed
	fi

	if [ $OK = 0 ]; then
		echo
		echo "Please, check the config file on $SLAVE manually."
		read -p "Pres ENTER to continue. "
	fi



	OK=0
	echo
	while [ $OK = 0 ]; do
		echo -n "Starting slave MySQL server ... "
		if ssh root@$SLAVE /etc/init.d/szn-mysql-server start > /dev/null 2>&1; then
			N=30
			while [ $N -gt 0 -a $OK = 0 ]; do
				sleep 1
				if ssh root@$SLAVE mysqladmin ping > /dev/null 2>&1; then
					echo OK
					OK=1
				else
					echo -n ". "
					N=$((N-1))
				fi
			done
			test $OK = 0 && f_ask_again
		else
			f_ask_again
		fi
	done



	OK=0
	PASS=`echo $PASS1 | sed "s/'/\\\\\\'/g"`
	echo
	while [ $OK = 0 ]; do
		echo -n "Setting up permissions on $MASTER ... "
		if ssh root@$MASTER "echo \"GRANT REPLICATION SLAVE ON *.* TO repl@'$SLAVE' IDENTIFIED BY '$PASS'; FLUSH PRIVILEGES\" | mysql" > /dev/null 2>&1; then
			echo OK
			OK=1
		else
			f_ask_again
		fi
	done

	OK=0
	while [ $OK = 0 ]; do
		echo -n "Setting up replication on $SLAVE ... "
		if ssh root@$SLAVE "echo \"CHANGE MASTER TO MASTER_HOST='$MASTER', MASTER_USER='repl', MASTER_PASSWORD='$PASS', MASTER_LOG_FILE='$LOGFILE', MASTER_LOG_POS=$LOGPOS;\" | mysql" > /dev/null 2>&1; then
			echo OK
			OK=1
		else
			f_ask_again
		fi
	done

	OK=0
	while [ $OK = 0 ]; do
		echo -n "Starting replication on $SLAVE ... "
		if ssh root@$SLAVE "echo \"SLAVE START;\" | mysql" > /dev/null 2>&1; then
			echo OK
			OK=1
		else
			f_ask_again
		fi
	done


	ssh root@$SLAVE -t "watch -n 5 \"echo 'SHOW SLAVE STATUS\\G' | mysql 2> /dev/null; echo; echo 'Press CTRL+C to exit.'\"" 2> /dev/null


	rm $TMPFILE
	echo
	echo "That's all for $SLAVE."
done

echo
echo "That's all."
exit 0