SSL Certificate Expiration

cert-watch.rb

#!/usr/bin/env ruby

require 'date'

certs = []
regex = /([\w\-\.]+):\s+Not After : (.+)/
today = Date.today

%x[grep -H 'Not After' #{ARGV.shift}].each_line do |line|
  data = regex.match line
  cert = data[1]
  next if certs.include? cert
  certs << cert
  date = Date.strptime data[2], "%b %e %H:%M:%S %Y %Z"
  days = date - today
  next if days > 7 or days < 0
  puts "#{cert} will expire in #{days} days!"
end