move metrics for ActiveRecord, RailsCache and queue duration to instance variables

1 files changed, 10 insertions, 8 deletions

diff --git a/lib/gitlab/middleware/rails_queue_duration.rb b/lib/gitlab/middleware/rails_queue_duration.rb
index e92f1835e20..bc70b2459ef 100644
--- a/lib/gitlab/middleware/rails_queue_duration.rb
+++ b/lib/gitlab/middleware/rails_queue_duration.rb
@@ -5,13 +5,6 @@
 module Gitlab
   module Middleware
     class RailsQueueDuration
-      def self.metric_rails_queue_duration_seconds
-        @metric_rails_queue_duration_seconds ||= Gitlab::Metrics.histogram(
-          :gitlab_rails_queue_duration_seconds,
-          Gitlab::Metrics::Transaction::BASE_LABELS
-        )
-      end
-
       def initialize(app)
         @app = app
       end
@@ -23,11 +16,20 @@ module Gitlab
           # Time in milliseconds since gitlab-workhorse started the request
           duration = Time.now.to_f * 1_000 - proxy_start.to_f / 1_000_000
           trans.set(:rails_queue_duration, duration)
-          self.class.metric_rails_queue_duration_seconds.observe(trans.labels, duration / 1_000)
+          metric_rails_queue_duration_seconds.observe(trans.labels, duration / 1_000)
         end
 
         @app.call(env)
       end
+
+      private
+
+      def metric_rails_queue_duration_seconds
+        @metric_rails_queue_duration_seconds ||= Gitlab::Metrics.histogram(
+          :gitlab_rails_queue_duration_seconds,
+          Gitlab::Metrics::Transaction::BASE_LABELS
+        )
+      end
     end
   end
 end