wp-cli update script as etc-cron.daily-wordpress-update

cat /etc/cron.daily/wordpress
#!/bin/sh
set -e

WWW_USER="www-data"
WWW_PATH="/var/www"

WPCLI_UPDATE=`wp cli check-update --allow-root 2>/dev/null \
                                | grep -v "Success: WP-CLI is at the latest version." | wc -l`

if test $WPCLI_UPDATE -gt 0
then
        wp cli update --allow-root --yes
fi

for wp_instance in `find ${WWW_PATH} -maxdepth 2 -name wp-config.php | xargs -L 1 dirname`
do
        CORE_UPDATE=`sudo -u ${WWW_USER} \
                wp core check-update --path=$wp_instance --field=version 2>/dev/null \
                        | grep -v "WordPress is at the latest version."   | wc -l`
        PLUGIN_UPDATES=`sudo -u ${WWW_USER} \
                wp plugin status     --path=$wp_instance 2>/dev/null | grep "^ U" | wc -l`
        THEME_UPDATES=`sudo -u ${WWW_USER} \
                wp theme status      --path=$wp_instance 2>/dev/null | grep "^ U" | wc -l`

        if test $CORE_UPDATE -gt 0 -o $PLUGIN_UPDATES -gt 0 -o $THEME_UPDATES -gt 0
        then
                echo "Updating ${}wp_instance}:"
                echo
        fi

        if test $CORE_UPDATE -gt 0
        then
                sudo -u ${WWW_USER} \
                        wp core update    --path=$wp_instance
                sudo -u ${WWW_USER} \
                        wp core update-db --path=$wp_instance
        fi

        if test $PLUGIN_UPDATES -gt 0
        then
                sudo -u ${WWW_USER} \
                        wp plugin update --all --path=$wp_instance
        fi

        if test $THEME_UPDATES -gt 0
        then
                sudo -u ${WWW_USER} \
                        wp theme update --all --path=$wp_instance
        fi

        if test $CORE_UPDATE -gt 0 -o $PLUGIN_UPDATES -gt 0 -o $THEME_UPDATES -gt 0
        then
                echo
                echo
        fi

done