Create sitemaps_controller.rb

app/controllers/sitemaps_controller.rb

@@ -0,0 +1,16 @@
+class SitemapsController < ApplicationController
+
+  layout :false
+  before_action :init_sitemap
+
+  def index
+    @forums = Forum.all
+  end
+
+  private
+
+  def init_sitemap
+    headers['Content-Type'] = 'application/xml'
+  end
+
+end