Commands to backup all databases except excluded ones into a current date folder. Restore allows to restore backups from specific date.

mysqldump - backup

#!/bin/bash
declare -a exclude=(information_schema mysql performance_schema sys default)

echo Mysql user ?
read user

echo Mysql password ?
read password

declare folder=$(date +%Y%m%d)
mkdir -p $folder

for DB in $(mysql --protocol=TCP -u $user -p$password -h mysql -e 'show databases' -s --skip-column-names); do
    if [[ ! ${exclude[*]} =~ $DB ]]; then
        mysqldump --protocol=TCP -u $user -p$password -h mysql $DB > "$folder/$DB.sql";
    fi
done

mysqldump - restore

#!/bin/bash
echo Mysql user ?
read user

echo Mysql password ?
read password

echo Backup date to be restored ?
read date

declare folder=$date

for DB in $folder/*; do
    fullfilename=$(basename -- "$DB")
    filename="${fullfilename%.*}"
    echo "Processing $filename file..."
    mysql --protocol=TCP -u $user -p$password -h mysql $filename < "$folder/$fullfilename";
done