#!/usr/bin/env ruby
#
# TMS table age check
# ===
#
# This checks when the last timestamp was for a particular table, and alerts if they are
# older than set thresholds.
#
# Copyright 2017 Critical Mention <ce@criticalmedia.com>
#
# Released under the same terms as Sensu (the MIT license); see LICENSE
# for details.

require 'inifile'
require 'mysql'
require 'sensu-plugin/check/cli'
require 'time'

class CheckTmsTableAge < Sensu::Plugin::Check::CLI
  option :user,
         description: 'MySQL User',
         short: '-u USER',
         long: '--user USER',
         default: 'root'

  option :password,
         description: 'MySQL Password',
         short: '-p PASS',
         long: '--password PASS'

  option :ini,
         description: 'My.cnf ini file',
         short: '-i',
         long: '--ini VALUE'

  option :hostname,
         description: 'Hostname to login to',
         short: '-h HOST',
         long: '--hostname HOST',
         required: true

  option :port,
         description: 'Port to connect to',
         short: '-P PORT',
         long: '--port PORT',
         default: '3306'

  option :socket,
         description: 'Socket to use',
         short: '-s SOCKET',
         long: '--socket SOCKET'

  option :database,
         description: 'Database to connect to',
         short: '-d DATABASE',
         long: '--database DATABASE',
         default: 'tms'

  option :table,
         description: 'Table to check timestamp of',
         short: '-t TABLE',
         long: '--table TABLE',
         required: true

  option :column,
         description: 'Timestamp column name',
         short: '-C COLUMN',
         long: '--column COLUMN',
         required: true

  option :warn_days,
         description: 'Issue warning when cc_text is older than number of days',
         short: '-w DAYS',
         long: '--warn DAYS',
         proc: proc(&:to_i), 
         default: 2

  option :critical_days,
         description: 'Issue alert when cc_text is older than number of days',
         short: '-c DAYS',
         long: '--critical DAYS',
         proc: proc(&:to_i),
         default: 3

  def run
    if config[:ini]
      ini = IniFile.load(config[:ini])
      section = ini['client']
      db_user = section['user']
      db_pass = section['password']
    else
      db_user = config[:user]
      db_pass = config[:password]
    end
    db = Mysql.real_connect(config[:hostname], db_user, db_pass, config[:database], config[:port].to_i, config[:socket])
    max_time_string = db.query("SELECT MAX(#{config[:column]}) AS max FROM #{config[:table]};").
      fetch_hash.
      fetch('max')
    max_time = Time.parse(max_time_string)
    sec_diff = Time.now - max_time
    if sec_diff >= (config[:critical_days] * 24 * 60 * 60)
      critical "Last '#{config[:column]}' time from #{config[:table]} is more than #{config[:critical_days]} days old"
    elsif sec_diff >= (config[:warn_days] * 24 * 60 * 60)
      warning "Last '#{config[:column]}' time from #{config[:table]} is more than #{config[:warn_days]} days old"
    else
      ok
    end
  rescue Mysql::Error => e
    critical "MySQL check failed: #{e.error}"
  ensure
    db.close if db
  end
end