add ActionController extension

lib/kashiwamochi/action_controller_extension.rb

@@ -0,0 +1,15 @@
+module Kashiwamochi
+  module ActionControllerExtension
+    extend ActiveSupport::Concern
+
+    module InstanceMethods
+
+      def build_search_query!
+        q = params.delete(Kashiwamochi.config.search_key)
+        instance_variable_set("@#{Kashiwamochi.config.search_key}", Kashiwamochi.build(q))
+      end
+      alias_method :build_query!, :build_search_query! unless defined?(build_query!)
+
+    end
+  end
+end

lib/kashiwamochi/railtie.rb

@@ -1,8 +1,12 @@
+require 'kashiwamochi/action_controller_extension'
 require 'kashiwamochi/action_view_extension'
 
 module Kashiwamochi
   class Railtie < Rails::Railtie
     initializer 'kashiwamochi.initialize' do
+      ActiveSupport.on_load(:action_controller) do
+        include Kashiwamochi::ActionControllerExtension
+      end
       ActiveSupport.on_load(:action_view) do
         include Kashiwamochi::ActionViewExtension
       end

spec/kashiwamochi/action_controller_extension_spec.rb

@@ -0,0 +1,38 @@
+require 'spec_helper'
+require 'action_controller/railtie'
+
+include Kashiwamochi::ActionControllerExtension
+
+describe Kashiwamochi::ActionControllerExtension do
+  describe '#build_search_query' do
+    before do
+      instance_eval <<-EOS
+        def params
+          @params
+        end
+      EOS
+    end
+    subject do
+      build_search_query!
+      @q
+    end
+
+    context 'with query' do
+      before do
+        @params = {:q => {:name => 'foo'}}
+      end
+
+      it { should be_an_instance_of Kashiwamochi::Query }
+      its(:name) { should eq 'foo' }
+    end
+
+    context 'without query' do
+      before do
+        @params = {}
+      end
+
+      it { should be_an_instance_of Kashiwamochi::Query }
+      its(:name) { should be_nil }
+    end
+  end
+end