scripts/wordpress_cron

#!/bin/sh

# This script do the following :
#	Use wp-cli (https://make.wordpress.org/cli/handbook/installing/)
#	Verify if an update is available for the WordPress core.
#		Create a file you need to monitore.
#	Verify if an update is available for WordPress plugins.
#		Create a file you need to monitore.

WP_ROOT="/var/www/wordpress"
WP_CLI_PATH="/usr/local/bin/wp"
WP_CORE_UPDATE_LOG="${WP_ROOT}/.update_core"
WP_PLUGIN_UPDATE_LOG="${WP_ROOT}/.update_plugin"

if [ ! -d "${WP_ROOT}" ]; then
	printf '%b' "${WP_ROOT} does not seem to be a WordPress install.\n"
	exit 1
fi

if [ ! -f "${WP_CLI_PATH}" ]; then
	printf '%b' "${WP_CLI_PATH} does not seem to be available.\n"
	exit 1
fi

# Verify if an update is available for WordPress
if sudo -u www-data -- "${WP_CLI_PATH}" --path="${WP_ROOT}" core check-update |grep -v -i -q -- "success"
then
	touch "${WP_CORE_UPDATE_LOG}"
	#printf '%b' "Please upgrade WordPress\n"
else
	rm -f "${WP_CORE_UPDATE_LOG}"
	#printf '%b' "Nothing to do\n"
fi

# Verify if updates are availables for plugins
if sudo -u www-data -- "${WP_CLI_PATH}" --path="${WP_ROOT}" plugin list|grep -q -i -- "available"
then
	touch "${WP_PLUGIN_UPDATE_LOG}"
	#printf '%b' "Please upgrade plugins\n"
else
	rm -f "${WP_PLUGIN_UPDATE_LOG}"
	#printf '%b' "Nothing to do\n"
fi

exit 0