Monitor only final statesrack-timeout-rename

There is no reason to monitor transition states so we ignore
ready and active states. We can get ratio of completed vs failed
requests from final states.

2 files changed, 25 insertions, 3 deletions

diff --git a/lib/gitlab/cluster/rack_timeout_observer.rb b/lib/gitlab/cluster/rack_timeout_observer.rb
index 2bc006b8011..5182b2be148 100644
--- a/lib/gitlab/cluster/rack_timeout_observer.rb
+++ b/lib/gitlab/cluster/rack_timeout_observer.rb
@@ -3,8 +3,10 @@
 module Gitlab
   module Cluster
     class RackTimeoutObserver
+      TRANSITION_STATES = %i(ready active).freeze
+
       def initialize
-        @counter = Gitlab::Metrics.counter(:rack_state_total, 'Number of requests in a given rack state')
+        @counter = Gitlab::Metrics.counter(:rack_requests_total, 'Number of requests in a given rack state')
       end
 
       # returns the Proc to be used as the observer callback block
@@ -17,6 +19,7 @@ module Gitlab
       def log_timeout_exception(env)
         info = env[::Rack::Timeout::ENV_INFO_KEY]
         return unless info
+        return if TRANSITION_STATES.include?(info.state)
 
         @counter.increment(labels(info, env))
       end
diff --git a/spec/lib/gitlab/cluster/rack_timeout_observer_spec.rb b/spec/lib/gitlab/cluster/rack_timeout_observer_spec.rb
index 2adb1d7cc71..68e5435450c 100644
--- a/spec/lib/gitlab/cluster/rack_timeout_observer_spec.rb
+++ b/spec/lib/gitlab/cluster/rack_timeout_observer_spec.rb
@@ -25,7 +25,7 @@ describe Gitlab::Cluster::RackTimeoutObserver do
 
       subject { described_class.new }
 
-      it 'increments timeout counter' do
+      it 'increments counter' do
         expect(counter)
           .to receive(:increment)
           .with({ controller: 'foo', action: 'bar', route: nil, state: :timed_out })
@@ -45,7 +45,7 @@ describe Gitlab::Cluster::RackTimeoutObserver do
 
       subject { described_class.new }
 
-      it 'increments timeout counter' do
+      it 'increments counter' do
         allow(endpoint).to receive_message_chain('route.pattern.origin') { 'foobar' }
         expect(counter)
           .to receive(:increment)
@@ -54,5 +54,24 @@ describe Gitlab::Cluster::RackTimeoutObserver do
         subject.callback.call(env)
       end
     end
+
+    context 'when request is being processed' do
+      let(:endpoint) { double }
+      let(:env) do
+        {
+          ::Rack::Timeout::ENV_INFO_KEY => double(state: :active),
+          Grape::Env::API_ENDPOINT => endpoint
+        }
+      end
+
+      subject { described_class.new }
+
+      it 'does not increment counter' do
+        allow(endpoint).to receive_message_chain('route.pattern.origin') { 'foobar' }
+        expect(counter).not_to receive(:increment)
+
+        subject.callback.call(env)
+      end
+    end
   end
 end