nixos/services.mysql: fix wait for galera cluster sync to be done (#381333)

            done

          ''}

          ${lib.optionalString isMariaDB ''

            # If MariaDB is used in an Galera cluster, we have to check if the sync is done,

            # or it will fail to init the database while joining, so we get in an broken non recoverable state

            # so we wait until we have an synced state

            if ${cfg.package}/bin/mysql -u ${superUser} -N -e "SHOW VARIABLES LIKE 'wsrep_on'" 2>/dev/null | ${lib.getExe' pkgs.gnugrep "grep"} -q 'ON'; then

              echo "Galera cluster detected, waiting for node to be synced..."

              while true; do

                STATE=$(${cfg.package}/bin/mysql -u ${superUser} -N -e "SHOW STATUS LIKE 'wsrep_local_state_comment'" | ${lib.getExe' pkgs.gawk "awk"} '{print $2}')

                if [ "$STATE" = "Synced" ]; then

                  echo "Node is synced"

                  break

                else

                  echo "Current state: $STATE - Waiting for 1 second..."

                  sleep 1

                fi

              done

            fi

          ''}

          if [ -f ${cfg.dataDir}/mysql_init ]

          then

              # While MariaDB comes with a 'mysql' super user account since 10.4.x, MySQL does not

                # Create initial databases

                if ! test -e "${cfg.dataDir}/${database.name}"; then

                    echo "Creating initial database: ${database.name}"

                    ( echo 'create database `${database.name}`;'

                    ( echo 'CREATE DATABASE IF NOT EXISTS `${database.name}`;'

                      ${lib.optionalString (database.schema != null) ''

                        echo 'use `${database.name}`;'

                        echo 'USE `${database.name}`;'

                        # TODO: this silently falls through if database.schema does not exist,

                        # we should catch this somehow and exit, but can't do it here because we're in a subshell.

              ${lib.optionalString (cfg.replication.role == "master") ''

                # Set up the replication master

                ( echo "use mysql;"

                ( echo "USE mysql;"

                  echo "CREATE USER '${cfg.replication.masterUser}'@'${cfg.replication.slaveHost}' IDENTIFIED WITH mysql_native_password;"

                  echo "SET PASSWORD FOR '${cfg.replication.masterUser}'@'${cfg.replication.slaveHost}' = PASSWORD('${cfg.replication.masterPassword}');"

                  echo "GRANT REPLICATION SLAVE ON *.* TO '${cfg.replication.masterUser}'@'${cfg.replication.slaveHost}';"

              ${lib.optionalString (cfg.replication.role == "slave") ''

                # Set up the replication slave

                ( echo "stop slave;"

                  echo "change master to master_host='${cfg.replication.masterHost}', master_user='${cfg.replication.masterUser}', master_password='${cfg.replication.masterPassword}';"

                  echo "start slave;"

                ( echo "STOP SLAVE;"

                  echo "CHANGE MASTER TO MASTER_HOST='${cfg.replication.masterHost}', MASTER_USER='${cfg.replication.masterUser}', MASTER_PASSWORD='${cfg.replication.masterPassword}';"

                  echo "START SLAVE;"

                ) | ${cfg.package}/bin/mysql -u ${superUser} -N

              ''}