Moved RackTimeout observer to a different location

Because there will be similar observer for PumaWorkerKiller,
it makes sense to keep both on better place.

1 files changed, 48 insertions, 0 deletions

diff --git a/lib/gitlab/cluster/rack_timeout_observer.rb b/lib/gitlab/cluster/rack_timeout_observer.rb
new file mode 100644
index 00000000000..2bc006b8011
--- /dev/null
+++ b/lib/gitlab/cluster/rack_timeout_observer.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Cluster
+    class RackTimeoutObserver
+      def initialize
+        @counter = Gitlab::Metrics.counter(:rack_state_total, 'Number of requests in a given rack state')
+      end
+
+      # returns the Proc to be used as the observer callback block
+      def callback
+        method(:log_timeout_exception)
+      end
+
+      private
+
+      def log_timeout_exception(env)
+        info = env[::Rack::Timeout::ENV_INFO_KEY]
+        return unless info
+
+        @counter.increment(labels(info, env))
+      end
+
+      def labels(info, env)
+        params = controller_params(env) || grape_params(env) || {}
+
+        {
+          controller: params['controller'],
+          action: params['action'],
+          route: params['route'],
+          state: info.state
+        }
+      end
+
+      def controller_params(env)
+        env['action_dispatch.request.parameters']
+      end
+
+      def grape_params(env)
+        endpoint = env[Grape::Env::API_ENDPOINT]
+        route = endpoint&.route&.pattern&.origin
+        return unless route
+
+        { 'route' => route }
+      end
+    end
+  end
+end