check-jsonwhois-domain-expiration.rb

#!/usr/bin/env ruby
# frozen_string_literal: false

#
#   check-jsonwhois-domain-expiration
#
# DESCRIPTION:
#   This plugin checks domain expiration dates using the https://jsonwhois.com API
#
# OUTPUT:
#   plain text
#
# PLATFORMS:
#   Any
#
# DEPENDENCIES:
#   gem: sensu-plugin
#
# USAGE:
#   ./check-jsonwhois-domain-expiration.rb -a [YOUR API KEY] -d foo.com,bar.com
#   JSONWhoisDomainExpirationCheck WARNING: foo.com: 30 days
#
# LICENSE:
#   Copyright 2015 Matt Greensmith (mgreensmith@cozy.co) - Cozy Services Ltd.
#   Based on check-whois-domain-expiration-multi, Copyright 2015 Tim Smith (tim@cozy.co) - Cozy Services Ltd.
#   Based on check-whois-domain-expiration, Copyright 2015 michael j talarczyk <mjt@mijit.com>
#    and contributors.
#   Released under the same terms as Sensu (the MIT license); see LICENSE
#   for details.

require 'sensu-plugin/check/cli'

require 'net/http'
require 'json'
require 'date'

#
# Check Whois domain expiration
#
class JSONWhoisDomainExpirationCheck < Sensu::Plugin::Check::CLI
  option :domain,
         short: '-d DOMAINS',
         long: '--domains DOMAIN',
         required: true,
         description: 'Comma-separated list of domains to check.'

  option :apikey,
         short: '-a APIKEY',
         long: '--apikey APIKEY',
         required: true,
         description: 'API key for jsonwhois.com'

  option :warning,
         short: '-w DAYS',
         long: '--warn DAYS',
         default: 30,
         description: 'Warn if a domain expires in fewer than DAYS days'

  option :critical,
         short: '-c DAYS',
         long: '--critical DAYS',
         default: 7,
         description: 'Critical if a domain expires in fewer than DAYS days'

  option :'ignore-errors',
         short: '-i',
         long: '--ignore-errors',
         boolean: true,
         default: false,
         description: 'Ignore connection or parsing errors'

  option :'report-errors',
         short: '-r LEVEL',
         long: '--report-errors LEVEL',
         proc: proc(&:to_sym),
         in: %i[unknown warning critical],
         default: :unknown,
         description: 'Level for reporting connection or parsing errors'

  option :help,
         short: '-h',
         long: '--help',
         description: 'Show this message',
         on: :tail,
         boolean: true,
         show_options: true,
         exit: 0

  # Split the provided domain list and perform whois lookups on each
  #
  # @return [Hash] a hash of severity_level -> domain -> days until expiry
  def expiration_results
    domains = config[:domain].split(',')
    warning_days = config[:warning].to_i
    critical_days = config[:critical].to_i
    results = {
      critical: {},
      warning: {},
      ok: {},
      unknown: {}
    }

    domains.each do |domain|
      begin
        expires_on = get_domain_expiration(domain)
        domain_result = (expires_on - DateTime.now).to_i
        if domain_result <= critical_days
          results[:critical][domain] = domain_result
        elsif domain_result <= warning_days
          results[:warning][domain] = domain_result
        else
          results[:ok][domain] = domain_result
        end
      rescue StandardError
        results[:unknown][domain] = 'Connection or parsing error' unless config[:'ignore-errors']
      end
    end
    results
  end

  # Fetch whois data from the JSONWhois API and return the "expires_on" date
  #
  # @param domain [String] the domain to fetch from JSONWhois
  # @return [DateTime] the expiration date for the domain
  def get_domain_expiration(domain)
    uri = URI('https://jsonwhois.com/api/v1/whois')
    uri.query = URI.encode_www_form(domain: domain)
    req = Net::HTTP::Get.new(uri)
    req['Authorization'] = "Token token=#{config[:apikey]}"

    res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: uri.scheme == 'https') do |http|
      http.request(req)
    end

    json = JSON.parse(res.body)
    DateTime.parse(json['expires_on'])
  end

  def run
    results = expiration_results

    warn_results = results[:critical].merge(results[:warning]).map { |u, v| "#{u} (#{v} days left)" }
    unknown_results = results[:unknown].map { |u, v| "#{u} (#{v})" }
    message warn_results.concat(unknown_results).join(', ')

    if !results[:critical].empty? || (!results[:unknown].empty? && config[:'report-errors'] == :critical)
      critical
    elsif !results[:warning].empty? || (!results[:unknown].empty? && config[:'report-errors'] == :warning)
      warning
    elsif !results[:unknown].empty?
      unknown
    else
      ok 'No domains expire in the near term'
    end
  end
end