gistfile1.rb

post '/create/subscription' do
  url_params = {
    :amount => 99,
    :interval_unit => 'month',
    :interval_length => 1,
    :name => 'Example Subscription',
    :description => 'Regular monthly payments (e.g., for hosting services)',
  }

  url = GoCardless.new_subscription_url(url_params)
  redirect to url
end