Silence debugbar routes from the logs

introduce QuietRoutes middleware

config/routes.rb

@@ -5,6 +5,5 @@
   options 'poll/confirm' => "polling#confirm"
   post 'poll/confirm' => "polling#confirm"
 
-  # TODO: Silence logs for this route if `::Rails.application.config.assets.quiet` is true
   get 'assets/script' => "assets#js"
 end

lib/debugbar/engine.rb

@@ -1,4 +1,5 @@
 require_relative 'config'
+require_relative 'middlewares/quiet_routes'
 require_relative 'middlewares/track_current_request'
 require_relative '../../app/helpers/debugbar/tag_helpers'
 
@@ -38,6 +39,7 @@ class Engine < ::Rails::Engine
     initializer 'debugbar.inject_middlewares' do |app|
       next unless Debugbar.config.enabled?
       app.middleware.insert_after ActionDispatch::Executor, Debugbar::TrackCurrentRequest
+      app.middleware.insert_after Sprockets::Rails::QuietAssets, Debugbar::QuietRoutes
     end
 
     initializer 'debugbar.subscribe' do

lib/debugbar/middlewares/quiet_routes.rb

@@ -0,0 +1,23 @@
+# This middleware silences the Rails logger for requests to the Debugbar routes.
+# The poll route can be *very* noisy.
+# Rails already does this for the /assets route, see Sprockets::Rails::QuietAssets.
+#
+# @see Sprockets::Rails::QuietAssets
+# @see Rails::Rack::Logger#silence
+#
+module Debugbar
+  class QuietRoutes
+    def initialize(app)
+      @app = app
+      @route_regex = %r(\A/{0,2}#{::Debugbar.config.prefix})
+    end
+
+    def call(env)
+      if env['PATH_INFO'] =~ @route_regex
+        ::Rails.logger.silence { @app.call(env) }
+      else
+        @app.call(env)
+      end
+    end
+  end
+end