Use canonical-rails gem to generate canonical URLs

config/initializers/canonical_rails.rb

@@ -0,0 +1,22 @@
+CanonicalRails.setup do |config|
+  # Force the protocol. If you do not specify, the protocol will be based on the incoming request's protocol.
+
+  # config.protocol#= 'https://'
+
+  # This is the main host, not just the TLD, omit slashes and protocol. If you have more than one, pick the one you want to rank in search results.
+
+  config.host = SERVER_URL
+
+  # http://en.wikipedia.org/wiki/URL_normalization
+  # Trailing slash represents semantics of a directory, ie a collection view - implying an :index get route;
+  # otherwise we have to assume semantics of an instance of a resource type, a member view - implying a :show get route
+  #
+  # Acts as a whitelist for routes to have trailing slashes
+
+  config.collection_actions = [:index]
+
+  # Parameter spamming can cause index dilution by creating seemingly different URLs with identical or near-identical content.
+  # Unless whitelisted, these parameters will be omitted
+
+  config.whitelisted_parameters = []
+end