Custom Responder for Service Objects

custom_service_responder.rb

module MyModule

  # This responder can be used with service objects.
  #
  # result = MyService.new.call
  # respond_with result, location: -> { payments_cards_path }
  #
  # Assumption: When we call the service, we get a status/response object which responds to `success?` method.
  # If response is successful, then the response object also responds to `data` method. If response is a
  # failure, the response object responds to `error` method.
  #
  # If the response is not a successful response, we also set flash(alert) message, using response object's `error` method.
  #
  # Since 'result' is not an ActiveRecord::Base object, we have to define a
  # location with 'location' parameter.
  #
  class CustomServiceResponder < ActionController::Responder
    include Responders::FlashResponder
    include Responders::HttpCacheResponder

    private

    def display(resource, options = {})
      super(resource.data, options)
    end

    def has_errors?
      !resource.success?
    end

    # set_flash_message! is overriden to use 'resource.error' method.
    def set_flash_message!
      if has_errors?
        status = Responders::FlashResponder.flash_keys.last
        set_flash(status, @alert)
      else
        status = Responders::FlashResponder.flash_keys.first
        set_flash(status, @notice)
      end

      return if controller.flash[status].present?

      if has_errors?
        message = resource.error
      else
        options = mount_i18n_options(status)
        message = Responders::FlashResponder.helper.t options[:default].shift, options
      end

      set_flash(status, message)
    end

  end
end