Add gauges; clean up stat parsing

lib/statsd.rb

@@ -72,6 +72,16 @@ def update_counter(stats, delta = 1, sample_rate = 1)
       send_stats(stats.map { |s| "#{s}:#{delta}|c" }, sample_rate)
     end
 
+    # +stats+ is a hash
+    def gauge(stats)
+      send_stats(stats.map { |s,val|
+                   if @prefix
+                     s = "#{@prefix}.#{s}"
+                   end
+                   "#{s}:#{val}|g"
+                 })
+    end
+
     private
 
     def send_stats(data, sample_rate = 1)

lib/statsd/server.rb

@@ -11,6 +11,7 @@ module Server
     FLUSH_INTERVAL = 10
     COUNTERS = {}
     TIMERS = {}
+    GAUGES = {}
 
     def post_init
       puts "statsd server started!"
@@ -19,9 +20,11 @@ def post_init
     def self.get_and_clear_stats!
       counters = COUNTERS.dup
       timers = TIMERS.dup
+      gauges = GAUGES.dup
       COUNTERS.clear
       TIMERS.clear
-      [counters,timers]
+      GAUGES.clear
+      [counters,timers,gauges]
     end
 
     def receive_data(msg)
@@ -37,12 +40,16 @@ def receive_data(msg)
           if (fields[1].strip == "ms")
             TIMERS[key] ||= []
             TIMERS[key].push(fields[0].to_i)
-          else
+          elsif (fields[1].strip == "c")
             if (fields[2] && fields[2].match(/^@([\d\.]+)/))
               sample_rate = fields[2].match(/^@([\d\.]+)/)[1]
             end
             COUNTERS[key] ||= 0
             COUNTERS[key] += (fields[0].to_i || 1) * (1.0 / sample_rate.to_f)
+          elsif (fields[1].strip == "g")
+            GAUGES[key] ||= (fields[0].to_i || 0)
+          else
+            puts "Invalid statistic #{fields.inspect} received; ignoring"
           end
         end
       end

spec/statsd_spec.rb

@@ -109,4 +109,22 @@
       c.decrement('foo')
     end
   end
+
+  describe '#gauge' do
+    let(:c) { Statsd::Client.new }
+
+    it 'should encode the values correctly' do
+      c.should_receive(:send_stats).with do |array|
+        array.should include('foo:1|g')
+        array.should include('bar:2|g')
+      end
+      c.gauge('foo' => 1, 'bar' => 2)
+    end
+
+    it 'should prepend the prefix if it has one' do
+      c.prefix = 'dev'
+      c.should_receive(:send_stats).with(['dev.foo:1|g'])
+      c.gauge('foo' => 1)
+    end
+  end
 end

statsd.gemspec

@@ -2,7 +2,7 @@
 
 Gem::Specification.new do |s|
   s.name        = "lookout-statsd"
-  s.version     = "0.5.#{ENV['BUILD_NUMBER'] || 'dev'}"
+  s.version     = "0.6.#{ENV['BUILD_NUMBER'] || 'dev'}"
   s.platform    = Gem::Platform::RUBY
 
   s.authors     = ['R. Tyler Croy', 'Andrew Coldham', 'Ben VandenBos']