Refactor Throttle#matched_by? method

Code Climate complains about the complexity of this method. Here we try to reduce it by using private methods that encapsulate some details that are not required to understand the implementation of the main method.

lib/rack/attack/throttle.rb

@@ -23,34 +23,50 @@ module Rack
 
       def matched_by?(request)
         discriminator = block.call(request)
+
         return false unless discriminator
 
-        current_period = period.respond_to?(:call) ? period.call(request) : period
-        current_limit  = limit.respond_to?(:call) ? limit.call(request) : limit
-        key            = "#{name}:#{discriminator}"
-        count          = cache.count(key, current_period)
-        epoch_time     = cache.last_epoch_time
+        current_period  = period_for(request)
+        current_limit   = limit_for(request)
+        count           = cache.count("#{name}:#{discriminator}", current_period)
 
         data = {
           discriminator: discriminator,
           count: count,
           period: current_period,
           limit: current_limit,
-          epoch_time: epoch_time
+          epoch_time: cache.last_epoch_time
         }
 
-        (request.env['rack.attack.throttle_data'] ||= {})[name] = data
-
         (count > current_limit).tap do |throttled|
+          annotate_request_with_throttle_data(request, data)
           if throttled
-            request.env['rack.attack.matched']             = name
-            request.env['rack.attack.match_discriminator'] = discriminator
-            request.env['rack.attack.match_type']          = type
-            request.env['rack.attack.match_data']          = data
+            annotate_request_with_matched_data(request, data)
             Rack::Attack.instrument(request)
           end
         end
       end
+
+      private
+
+      def period_for(request)
+        period.respond_to?(:call) ? period.call(request) : period
+      end
+
+      def limit_for(request)
+        limit.respond_to?(:call) ? limit.call(request) : limit
+      end
+
+      def annotate_request_with_throttle_data(request, data)
+        (request.env['rack.attack.throttle_data'] ||= {})[name] = data
+      end
+
+      def annotate_request_with_matched_data(request, data)
+        request.env['rack.attack.matched']             = name
+        request.env['rack.attack.match_discriminator'] = data[:discriminator]
+        request.env['rack.attack.match_type']          = type
+        request.env['rack.attack.match_data']          = data
+      end
     end
   end
 end