damp_create_cluster.sh

#!/bin/bash
#brew install gnu-sed
currdir=`pwd`
servers="$currdir/damp/hostfile"
touch $servers
#server1 will be the initial master

numargs=$#
if [ $numargs -lt 2 ]; then
        echo "usage $0 clustername num_of_servers_including_master"
        exit 1
fi

server_name=damp_server_$1
num_of_servers=$2
replication_type=${3:-gtid}
last_hostgroup=$(grep "hostgroup" $servers |tail -n 1 |cut -d":" -f 2 |sed 's/ //' )
if [[ -z "$last_hostgroup" ]]
    then
        hostgroup=1
        echo -e "[proxysql]\nlocalhost\n\n" >>$servers
    else 
        hostgroup=$(( $last_hostgroup + 2 ))   
fi 


list=$(docker ps -a --format '{{.Names}}'|grep -E "^${server_name}[0-9]{1,2}$")
if [[ "$list" != "" ]]
then
    echo "Containers with name: $server_name are already running, quit!"
    exit 1
fi

docker-ip() {
    local ip=$(docker inspect --format '{{ .NetworkSettings.IPAddress }}' "$@")
    echo $ip
}



echo "Starting the following containers in $server_name cluster:"
for i in $(seq 1  $num_of_servers)
do
    mkdir -p $currdir/mysql_hosts/${server_name}${i}/conf.d $currdir/mysql_hosts/${server_name}${i}/log_mysql
    if [ $i ==  "1" ] 
    then
        sed   -e "s/server-id=/server-id=1/" -e "s/read_only=1/read_only=0/"  $currdir/my.cnf> $currdir/mysql_hosts/${server_name}${i}/conf.d/my.cnf
    else
        sed   -e  "s/server-id=/server-id=${i}/"  $currdir/my.cnf> $currdir/mysql_hosts/${server_name}${i}/conf.d/my.cnf
    fi
    if [ "$replication_type" == "gtid" ]
    then
	echo "gtid-mode=ON" >>$currdir/mysql_hosts/${server_name}${i}/conf.d/my.cnf
	echo "enforce-gtid-consistency" >>$currdir/mysql_hosts/${server_name}${i}/conf.d/my.cnf
    fi

    cid=$(docker run --name ${server_name}${i} -h ${server_name}${i}  -d -v $currdir/mysql_hosts/${server_name}${i}/conf.d:/etc/mysql/conf.d -v $currdir/mysql_hosts/${server_name}${i}/log_mysql:/var/log/mysql  -e MYSQL_ROOT_PASSWORD=mysecretpass -d mysql:5.6)

    server_ip=$( docker-ip $cid )
    echo "${server_name}${i} $cid($server_ip)"
    serverlist=("${serverlist[@]}" "$server_ip" )

    if [ $i ==  "1" ]
    then
        master_ip=$server_ip
    fi

done


#waiting for the last server to be available
isup=0

until [ $isup -eq "1" ]

do
    isup=$(docker exec -ti ${server_name}${num_of_servers}  'mysql' -NB -uroot -pmysecretpass -e"select(234);" |grep "234" |wc -l )
    sleep 3
    echo "waiting for the ${server_name}${num_of_servers} to be available"
done

echo "add replication user to the master (${server_name})"
docker exec -ti ${server_name}1  'mysql' -uroot -pmysecretpass -vvv -e "select @@version;"
docker exec -ti ${server_name}1  'mysql' -uroot -pmysecretpass -vvv -e "GRANT REPLICATION SLAVE ON *.* TO repl@'%' IDENTIFIED BY 'slavepass'\G"

#configure replication on all hosts
for i in $(seq 2  $num_of_servers)
do
    if [ "$replication_type" == "gtid" ]
    then
	docker exec -ti ${server_name}${i}  'mysql' -uroot -pmysecretpass -e"change master to master_host='$master_ip',master_user='repl',master_password='slavepass',master_auto_position = 1;" -vvv
    else
	docker exec -ti ${server_name}${i}  'mysql' -uroot -pmysecretpass -e"change master to master_host='$master_ip',master_user='repl',master_password='slavepass',master_log_file='mysqld-bin.000004',master_log_pos=120;" -vvv
    fi

    echo "start replication"
    docker exec -ti ${server_name}${i}  'mysql' -uroot -pmysecretpass -e"START SLAVE\G" -vvv 

    echo "show slave status"
    docker exec -ti ${server_name}${i}  'mysql' -uroot -pmysecretpass -e"SHOW SLAVE STATUS\G" -vvv

done

#update the ansible yml file with this cluster's data
echo -e "[${server_name}]" >>$servers
for item in ${serverlist[*]}
do
    if [ "$item" == "$master_ip" ] 
    then
        echo "$item mysql_role=master" >>$servers
    else
        echo "$item mysql_role=slave" >>$servers
    fi
done
echo -e "\n[${server_name}:vars]
cluster=${server_name}
hostgroup=$hostgroup
\n" >>$servers