demarches-normaliennes/app/controllers/application_controller.rb

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception

  def default_url_options
    return { protocol: 'https' } if Rails.env.staging? || Rails.env.production?
    {}
  end
end