Check SSL expiry and show notification

shell

#!/bin/bash
# Domains to be checked
Domains=(example1.com example2.com)

# Port
Port="443"

# Show notification before n days before expiration 
NoticeBeforeDays="30"

# Title of notification
TITLE="HTTP证书检查"

# Sound are in /System/Library/Sounds
SOUND="Frog"

for N in "${Domains[@]}" ; do
	Domain=$N

	# Get expiration date with Openssl tool
	Cert_END_Time=$(echo | openssl s_client -servername ${Domain} -connect ${Domain}:${Port} 2> /dev/null | openssl x509 -noout -dates | grep 'After' | awk -F '=' '{print $2}' | awk '{print "-v" $1 "m -v" $2 "d -v" $4 "y"}')

	# Covert date to timestamp
	Cert_END_TimeStamp=$(date -j "$Cert_END_Time" '+%s')

	# Get current timestamp
	Create_TimeStamp=$(date +%s)

	# Calculate how many days left to expiration date
	Rest_Time=$(expr $(expr $Cert_END_TimeStamp '-' $Create_TimeStamp) / 86400)

	Msg=''
	# Set display message
	if [ $Rest_Time -le 0 ]; then
	  Msg="❌ ${Domain} already expired!"
	elif [ $Rest_Time -lt $NoticeBeforeDays ];then
	  Msg="⚠️ ${Domain} ${Rest_Time} days left until expire"
	# else
	#   echo "✅ ${Domain}"
	fi

	osascript -e 'display notification "'"$Msg"'" with title "'"$TITLE"'" sound name "'"$SOUND"'"'
done