Sensu Check when an upcoming date is approaching

I have a need for a Sensu check that will a warn X number of days before a specific date and/or issue a critical alert X numbers of days before a date.

Writing the check ruby code

Install the following gems (if you don't already have them)

> sudo gem install chronic     > sudo gem install sensu-plugin

Create the plugin

> sudo vi /etc/sensu/plugins/check_date.rb

I created a gist of the code at https://gist.github.com/patmandenver/0e753184c789dc0f40eb

Code

#!/usr/bin/ruby # # #The MIT License (MIT) # #Copyright (c) 2015 Patrick Bailey # #Permission is hereby granted, free of charge, to any person obtaining a copy #of this software and associated documentation files (the "Software"), to deal #in the Software without restriction, including without limitation the rights #to use, copy, modify, merge, publish, distribute, sublicense, and/or sell #copies of the Software, and to permit persons to whom the Software is #furnished to do so, subject to the following conditions: # #       The above copyright notice and this permission notice shall be included in all #copies or substantial portions of the Software. # #       THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR #IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, #FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE #AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER #LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, #       OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE #SOFTWARE. # # require 'rubygems' if RUBY_VERSION < '1.9.0' require 'sensu-plugin/check/cli' require 'chronic' class CheckDate < Sensu::Plugin::Check::CLI   option :date,          :description => "date to check agains",          :short => '-d DATE',          :long => '--date DATE',          :required => true   option :days_warn_before,          :description => "If set will issue a warning if within X number of days of given date",          :short => '-w DAYS_WARN_BEFORE',          :long => '--warn DAYS_WARN_BEFORE',          :default => 30,          :required => true   option :days_alarm_before,          :description => "If set will issue an alarm if within X number of days of given date",          :short => '-a DAYS_ALARM_BEFORE',          :long => '--alarm DAYS_ALARM_BEFORE',          :default => 15,          :required => true   option :message,          :description => "Message to send",          :short => '-m MESSAGE',          :long => '--message MESSAGE',          :required => true   def initilize     super   end   def run     date = Chronic.parse(config[:date])     #Confirm the date given is valid see https://github.com/mojombo/chronic#usage     if date.nil?       critical("Invalid date format '" + config[:date] + "', An example of a valid forma is '12/3/2014'")     end     if (date - config[:days_alarm_before].to_i*24*3600) < Time.now       critical(config[:message])     elsif (date - config[:days_warn_before].to_i*24*3600) < Time.now       warning(config[:message])     else       ok("No need to issue alarm or warning for date '" + date.to_s)     end   end end

Create a check (to test it out)

> sudo vi /etc/sensu/conf.d/check_license_ends.json

Here is my simple check (adjust it to your system)

{     "checks": {         "check_license_ends": {             "handlers": [                 "default"             ],             "command": "/etc/sensu/plugins/check_date.rb -d 1/30/15 -m 'License runs out on 1/30/2015'",             "interval": 60,             "occurrences": 1,             "refresh": 3600,             "subscribers": [                 "check-from-sensu-master"             ]         }     } }

Save it and restart the Sensu Master with the following command, and its client

> sudo service sensu-server restart && sudo service sensu-api restart && sudo service sensu-client restart

And there is my warning.

If I update the check to the following (To trigger an alert today… today is 1/13/2015)

{     "checks": {         "check_license_ends": {             "handlers": [                 "default"             ],             "command": "/etc/sensu/plugins/check_date.rb -d 1/30/15 -a 20 -w 7 -m 'License runs out on 1/30/2015'",             "interval": 60,             "occurrences": 1,             "refresh": 3600,             "subscribers": [                 "check-from-sensu-master"             ]         }     } }

And there is my critical

In a real system I would probably update the interval to 21600 (every 6 hours) or 86400 (every 24 hours)

References

This post is a part of and epic, the Sensu Epic.

Epic Goal:    My goal is to just really figure out how to use Sensu.