Update rack metric names

* Follow Prometheus naming conventions[0].
* Simplify metrics by adding response lables to the histogram.
* Use standard `http_request_duration_seconds_...` names for the histogram.

[0]: https://prometheus.io/docs/practices/naming/#metric-names

1 files changed, 4 insertions, 9 deletions

diff --git a/lib/gitlab/metrics/connection_rack_middleware.rb b/lib/gitlab/metrics/connection_rack_middleware.rb
index b3da360be8f..ac87e481dbd 100644
--- a/lib/gitlab/metrics/connection_rack_middleware.rb
+++ b/lib/gitlab/metrics/connection_rack_middleware.rb
@@ -6,19 +6,15 @@ module Gitlab
       end
 
       def self.rack_request_count
-        @rack_request_count ||= Gitlab::Metrics.counter(:rack_request, 'Rack request count')
-      end
-
-      def self.rack_response_count
-        @rack_response_count ||= Gitlab::Metrics.counter(:rack_response, 'Rack response count')
+        @rack_request_count ||= Gitlab::Metrics.counter(:http_requests_total, 'Rack request count')
       end
 
       def self.rack_uncaught_errors_count
-        @rack_uncaught_errors_count ||= Gitlab::Metrics.counter(:rack_uncaught_errors, 'Rack connections handling uncaught errors count')
+        @rack_uncaught_errors_count ||= Gitlab::Metrics.counter(:rack_uncaught_errors_total, 'Rack connections handling uncaught errors count')
       end
 
       def self.rack_execution_time
-        @rack_execution_time ||= Gitlab::Metrics.histogram(:rack_execution_time, 'Rack connection handling execution time',
+        @rack_execution_time ||= Gitlab::Metrics.histogram(:http_request_duration_seconds, 'Rack connection handling execution time',
                                                            {}, [0.05, 0.1, 0.25, 0.5, 0.7, 1, 1.5, 2, 2.5, 3, 5, 7, 10])
       end
 
@@ -30,14 +26,13 @@ module Gitlab
 
           status, headers, body = @app.call(env)
 
-          ConnectionRackMiddleware.rack_response_count.increment(method: method, status: status)
           [status, headers, body]
         rescue
           ConnectionRackMiddleware.rack_uncaught_errors_count.increment
           raise
         ensure
           elapsed = Time.now.to_f - started
-          ConnectionRackMiddleware.rack_execution_time.observe({}, elapsed)
+          ConnectionRackMiddleware.rack_execution_time.observe({method: method, status: status}, elapsed)
         end
       end
     end