Keeps Heroku servers awake

heroku-pinger.sh

#!/bin/bash

# - Curls Heroku servers indicated in the "hosts" file.
# - Logs actions to log files (unique per host), including the response HTTP status
# - Clean up log files if > 5mb
#
# Simply add the target hosts in the "hosts" file, like:
# my-server-01.herokuapp.com
# my-server-02.herokuapp.com
# NOTICE: There must be a new line at the end of the "hosts" file.
#
# Remember:
# - To "chmod a+x heroku-pinger.sh"
# - On Mac:
#  - Give "Full Disk Access" to "/usr/sbin/cron"
#  - Give "Full Disk Access" to the "Terminal" app
#
# Cron job, every 20 minutes:
# */20 * * * * bash /Users/fernando.fernandes/Documents/Projects/Software/Scripts/Heroku/heroku-pinger.sh

cat /Users/fernando.fernandes/Documents/Projects/Software/Scripts/Heroku/hosts |  while read hostname

# Loop over the list of hosts.
do
	status=`curl -Is ${hostname} | grep HTTP | cut -d ' ' -f2`
	d=`date +%Y-%m-%d`
	t=`date +%I-%M-%S-%p`
	day=`date +%A`

	# Create the log file in the following format: "host-hostname..."
	hostLogFilePrefix="host-"
	hostLogFile="$hostLogFilePrefix${hostname}"

	# Cleanup time! Check if the host log file exists.
	wc -c $hostLogFile.log &>/dev/null
	if [ $? -eq 0 ]
	then
		# If the file is greater than 5MB, clean it first.
		fileSize=`wc -c $hostLogFile.log | awk '{print $1}'`
		if [ $fileSize -gt 5242880 ]
		then
			:> $hostLogFile.log
		fi
	fi

	# Save log to the host log file.
	echo "$d    $t    $day    $status" >> /Users/fernando.fernandes/Documents/Projects/Software/Scripts/Heroku/$hostLogFile.log
done