(RE-7014) Add support for statsd

They way we were using graphite was incorrect for the type of data we were sending it.  statsd is the appropriate mechanism for our needs.
statsd and graphite are mutually exclusive and configuring statsd will take precendence over Graphite.  Example of configuration in vmpooler.yaml.example

lib/vmpooler.rb

@@ -7,6 +7,7 @@ module Vmpooler
   require 'rbvmomi'
   require 'redis'
   require 'sinatra/base'
+  require "statsd-ruby"
   require 'time'
   require 'timeout'
   require 'yaml'
@@ -52,6 +53,13 @@ module Vmpooler
       parsed_config[:graphite]['prefix'] ||= 'vmpooler'
     end
 
+    # statsd is an addition and my not be present in YAML configuration
+    if parsed_config[:statsd]
+      if parsed_config[:statsd]['server']
+        parsed_config[:statsd]['prefix'] ||= 'vmpooler'
+      end
+    end
+
     if parsed_config[:tagfilter]
       parsed_config[:tagfilter].keys.each do |tag|
         parsed_config[:tagfilter][tag] = Regexp.new(parsed_config[:tagfilter][tag])
@@ -79,6 +87,14 @@ module Vmpooler
     end
   end
 
+  def self.new_statsd(server, port)
+    if server.nil? or server.empty? or server.length == 0
+      nil
+    else
+      Statsd.new server, port
+    end
+  end
+
   def self.pools(conf)
     conf[:pools]
   end

lib/vmpooler/pool_manager.rb

@@ -1,12 +1,17 @@
 module Vmpooler
   class PoolManager
-    def initialize(config, logger, redis, graphite=nil)
+    def initialize(config, logger, redis, graphite=nil, statsd=nil)
       $config = config
 
       # Load logger library
       $logger = logger
 
-      unless graphite.nil?
+      # statsd and graphite are mutex in the context of vmpooler
+      unless statsd.nil?
+        $statsd = statsd
+      end
+
+      unless graphite.nil? || !statsd.nil?
         $graphite = graphite
       end
 
@@ -258,6 +263,7 @@ module Vmpooler
         $redis.decr('vmpooler__tasks__clone')
 
         begin
+          $statsd.timing($config[:statsd]['prefix'] + ".clone.#{vm['template']}", finish) if defined? $statsd
           $graphite.log($config[:graphite]['prefix'] + ".clone.#{vm['template']}", finish) if defined? $graphite
         rescue
         end
@@ -565,7 +571,10 @@ module Vmpooler
       total = $redis.scard('vmpooler__pending__' + pool['name']) + ready
 
       begin
-        if defined? $graphite
+        if defined? $statsd
+          $statsd.increment($config[:statsd]['prefix'] + '.ready.' + pool['name'], $redis.scard('vmpooler__ready__' + pool['name']))
+          $statsd.increment($config[:statsd]['prefix'] + '.running.' + pool['name'], $redis.scard('vmpooler__running__' + pool['name']))
+        elsif defined? $graphite
           $graphite.log($config[:graphite]['prefix'] + '.ready.' + pool['name'], $redis.scard('vmpooler__ready__' + pool['name']))
           $graphite.log($config[:graphite]['prefix'] + '.running.' + pool['name'], $redis.scard('vmpooler__running__' + pool['name']))
         end

lib/vmpooler/statsd.rb

@@ -0,0 +1,12 @@
+require 'rubygems' unless defined?(Gem)
+
+module Vmpooler
+  class Statsd
+    def initialize(
+      s = 'statsd',
+      port = 8125
+    )
+      @server = Statsd.new s, port
+    end
+  end
+end