use canonical-url plugin to make view more clean

lib/canonical_url.rb

@@ -0,0 +1,43 @@
+module CanonicalURL
+  module ControllerExtensions
+    def canonical_url(url_for_options = {})
+      case url_for_options
+      when Hash
+        @canonical_url = url_for(url_for_options)
+      else
+        @canonical_url = url_for_options
+      end
+    end
+  end
+
+  module Helpers
+    def canonical_link_tag(url = nil)
+
+      return '' unless url || @canonical_url
+      tag('link', :rel => 'canonical', :href => url || @canonical_url || request.url)
+    end
+  end
+end
+
+# https://github.com/mbleigh/canonical-url/blob/master/lib/canonical_url.rb
+
+# Copyright (c) 2009 Michael Bleigh and Intridea, Inc.
+# 
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+# 
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+# 
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.#