Fix compatibility with newer versions of Graphite (#64)

* Fix compatibility with newer versions of Graphite

Tags require brackets with newer versions of graphite.

CHANGELOG.md

@@ -4,6 +4,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed at [Keep A Changelog](http://keepachangelog.com/)
 
 ## [Unreleased]
+### Added
+- Added -t flag to handler-graphite-event.rb to support post 1.0 versions of graphite which require tags sent as arrays.
 
 ## [3.0.0] - 2017-12-04
 ### Breaking Change

bin/handler-graphite-event.rb

@@ -22,6 +22,14 @@
 require 'json'
 
 class GraphiteEvent < Sensu::Handler
+  option :tags_as_array,
+         description: 'send tags as array - for post graphite 1.0 compatibility.',
+         short: '-t',
+         long: '--tags-as-array',
+         boolean: true,
+         required: false,
+         default: false
+
   def post_event(uri, body)
     uri          = URI.parse(uri)
     req          = Net::HTTP::Post.new(uri.path)
@@ -60,7 +68,7 @@ def handle
 
     body = {
       'what' => 'sensu_event',
-      'tags' => tags.join(','),
+      'tags' => config[:tags_as_array] ? [tags.join(',')] : tags.join(','),
       'data' => event_status,
       'when' => Time.now.to_i
     }