Auto renewal for Let's Encrypt Apache

le-renew.sh

#!/bin/bash
#================================================================
# Let's Encrypt renewal script for Apache on Ubuntu/Debian
# @author Erika Heidi<erika@do.co>
# Usage: ./le-renew.sh [base-domain-name]
# More info: http://do.co/1mbVihI
#================================================================
domain=$1
le_path='/opt/letsencrypt'
le_conf='/etc/letsencrypt'
exp_limit=30;

get_domain_list(){
        certdomain=$1
        config_file="$le_conf/renewal/$certdomain.conf"
        
	if [ ! -f $config_file ] ; then
                echo "[ERROR] The config file for the certificate $certdomain was not found."
                exit 1;
        fi

        domains=$(grep --only-matching --perl-regex "(?<=domains \= ).*" "${config_file}")
        last_char=$(echo "${domains}" | awk '{print substr($0,length,1)}')

        if [ "${last_char}" = "," ]; then
                domains=$(echo "${domains}" |awk '{print substr($0, 1, length-1)}')
        fi

        echo $domains;
}

if [ -z "$domain" ] ; then
        echo "[ERROR] you must provide the domain name for the certificate renewal."
        exit 1;
fi

cert_file="/etc/letsencrypt/live/$domain/fullchain.pem"

if [ ! -f $cert_file ]; then
	echo "[ERROR] certificate file not found for domain $domain."
	exit 1;
fi

exp=$(date -d "`openssl x509 -in $cert_file -text -noout|grep "Not After"|cut -c 25-`" +%s)
datenow=$(date -d "now" +%s)
days_exp=$(echo \( $exp - $datenow \) / 86400 |bc)

echo "Checking expiration date for $domain..."

if [ "$days_exp" -gt "$exp_limit" ] ; then
	echo "The certificate is up to date, no need for renewal ($days_exp days left)."
	exit 0;
else
	echo "The certificate for $domain is about to expire soon. Starting renewal request..."
	domain_list=$( get_domain_list $domain )
	"$le_path"/letsencrypt-auto certonly --apache --renew-by-default --domains "${domain_list}"
	echo "Restarting Apache..."
	/usr/sbin/service apache2 reload
	echo "Renewal process finished for domain $domain"
	exit 0;
fi

I used this script for a while and found it wasn't working either. This article really helped me:
https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-14-04

It covers starting out through settings up auto-renew, but it definitely covered all the bases for me.

How does this compare to certbot for renewal? Is this script created before certbot was around? Which is the best practice today?