def custom_filters
      self.resource_class.report_filter_options.select{|filter| viable_report_filters.map(&:filter_name).exclude? filter.param}
    end
def custom_filters
      self.resource_class.report_filter_options.select{|filter| viable_report_filters.map(&:filter_name).exclude? filter.param}
    end
These are the filters available at runtime, ie. not including the ones set to define this report.
 If updating the report, this is the set available to add as new report definition filters.