def receive_optout_post(params, request)
      if request.post?
        [:action, :email, :sig].each { |key| return false unless params.has_key?(key) }

        return false unless params[:action] == 'optout'

        sig = params.delete(:sig)
        params.delete(:controller)
        sig == get_signature_hash(params, @secret)
      else
        false
      end
    end
def receive_optout_post(params, request)
      if request.post?
        [:action, :email, :sig].each { |key| return false unless params.has_key?(key) }

        return false unless params[:action] == 'optout'

        sig = params.delete(:sig)
        params.delete(:controller)
        sig == get_signature_hash(params, @secret)
      else
        false
      end
    end
params:
   params, Hash
   request, String
 returns:
   TrueClass or FalseClass, Returns true if the incoming request is an authenticated optout post.