Merge pull request #96 from dinomite/master

Plugin to report metrics to MetricCatcher (LOGSTASH-393)

lib/logstash/outputs/metriccatcher.rb

@@ -0,0 +1,64 @@
+require "logstash/outputs/base"
+require "logstash/namespace"
+require "json"
+
+# This output ships metrics to MetricCatcher, allowing you to
+# utilize Coda Hale's Metrics.
+#
+# More info on MetricCatcher: https://github.com/clearspring/MetricCatcher
+#
+# At Clearspring, we use it to count the response codes from Apache logs:
+#     metriccatcher {
+#         host => "localhost"
+#         port => "1420"
+#         type => "apache-access"
+#         fields => [ "response" ]
+#         meter => [ "%{@source_host}.apache.response.%{response}", "1" ]
+#     }
+class LogStash::Outputs::MetricCatcher < LogStash::Outputs::Base
+  config_name "metriccatcher"
+  plugin_status "beta"
+
+  # The address of the MetricCatcher
+  config :host, :validate => :string, :default => "localhost"
+  # The port to connect on your MetricCatcher
+  config :port, :validate => :number, :default => 1420
+
+  # The metrics to send. This supports dynamic strings like %{@source_host}
+  # for metric names and also for values. This is a hash field with key 
+  # of the metric name, value of the metric value. Example:
+  #
+  #   counter => [ "%{@source_host}.apache.hits", "1", "widgets.served.doubled", "2" ]
+  #   meter => [ "%{@source_host}.apache.response.%{response}", "1" ]
+  #
+  # The value will be coerced to a floating point value. Values which cannot be
+  # coerced will zero (0)
+  @@metric_types = ["gauge", "counter", "meter", "biased", "uniform", "timer"]
+  @@metric_types.each do |metric_type|
+    config metric_type, :validate => :hash
+  end
+
+  def register
+    @socket = UDPSocket.new
+  end # def register
+
+  public
+  def receive(event)
+    return unless output?(event)
+
+    @@metric_types.each do |metric_type|
+      if instance_variable_defined?("@#{metric_type}")
+        instance_variable_get("@#{metric_type}").each do |metric_name, metric_value|
+          message = [{
+            "name"      => event.sprintf(metric_name),
+            "type"      => event.sprintf(metric_type),
+            "value"     => event.sprintf(metric_value).to_f,
+            "timestamp" => event.sprintf("%{+%s}.") + Time.now.usec.to_s
+          }]
+
+          @socket.send(message.to_json, 0, @host, @port)
+        end # instance_variable_get("@#{metric_type}").each_slice
+      end # if
+    end # @metric_types.each
+  end # def receive
+end # class LogStash::Outputs::MetricCatcher