gistfile1.rb

Warden::Strategies.add(:openid) do
  def valid?
    !params["openid_identifier"].blank?
  end

  def authenticate!
    if resp = env[Rack::OpenID::RESPONSE]
      RAILS_DEFAULT_LOGGER.info "Attempting OpenID auth: #{env["rack.openid.response"].inspect}"
      case resp.status
      when :success
        u = Person.find_for_authentication(:openid_url => resp.identity_url)
        success!(u)
      when :cancel
        fail!("OpenID auth cancelled")
      when :failure
        fail!("OpenID auth failed")
      end
    else
      header_data = Rack::OpenID.build_header(:identifier => params["openid_identifier"])
      RAILS_DEFAULT_LOGGER.info header_data
      custom!([401, {
            Rack::OpenID::AUTHENTICATE_HEADER => header_data
          }, "Sign in with OpenID"])
    end
  end
end