Extract current_conference assignment in a concern

app/controllers/application_controller.rb

@@ -1,9 +1,5 @@
 class ApplicationController < ActionController::Base
-  def require_current_conference
-    if not current_conference?
-      redirect_to '/', alert: 'No conference selected'
-    end
-  end
+  include CurrentConferenceAssigning
 
   # Prevent CSRF attacks by raising an exception.
   # For APIs, you may want to use :null_session instead.

app/controllers/concerns/current_conference_assigning.rb

@@ -0,0 +1,26 @@
+module CurrentConferenceAssigning
+  extend ActiveSupport::Concern
+
+  included do
+    helper_method :current_conference?
+    helper_method :current_conference
+  end
+
+  def current_conference?
+    current_conference.present?
+  end
+
+  def current_conference
+    if not @current_conference and params[:conference_id].present?
+      @current_conference = Conference.find(params[:conference_id])
+    end
+
+    @current_conference
+  end
+
+  def require_current_conference!
+    if not current_conference?
+      raise ActionController::RoutingError.new('Not Found')
+    end
+  end
+end

app/controllers/management/management_controller.rb

@@ -6,24 +6,6 @@ module Management
 
     private
 
-    def current_conference?
-      current_conference.present?
-    end
-    helper_method :current_conference?
-
-    def current_conference
-      if not @current_conference
-        if @conference
-          @current_conference = @conference
-        elsif params[:conference_id].present?
-          @current_conference = Conference.find(params[:conference_id])
-        end
-      end
-
-      @current_conference
-    end
-    helper_method :current_conference
-
     def authorize_user!
       head :forbidden unless current_user.admin?
     end