This project rocks and uses MIT-LICENSE, foh sho. Works with rails 3 and 4.
A number of articles exist explaining the issue concisely and at length:
- Google Webmaster Blog Page About Specifying Canonical
- Google Support About rel="canonical"
- Google Support About Canonicalization
I've seen a lot of folks do more harm by neglecting canonicalization altogether than by applying to narrowly and conservatively, so here is an attempt to let people start modestly without spending too much time on it and whitelist parameters as they need to.
gem 'canonical-rails', github: 'jumph4x/canonical-rails'
First, generate the config
rails g canonical_rails:install
Then find it in config/initializers/ as canonical_rails.rb
Finally, include the canonical_tag helper in your views:
<%= canonical_tag -%>