flippercloud/flipper · error · Flipper::UI::InvalidConfigurationValue

The banner_class provided '#{value}' is not one of: danger,

Error message

The banner_class provided '#{value}' is not one of: danger, dark, info, light, primary, secondary, success, warning

What it means

Error "The banner_class provided '#{value}' is not one of: danger, dark, info, light, primary, secondary, success, warning" thrown in flippercloud/flipper.

Source

Thrown at lib/flipper/ui/configuration.rb:156

      def using_descriptions?
        @descriptions_source != DEFAULT_DESCRIPTIONS_SOURCE
      end

      def show_feature_description_in_list?
        using_descriptions? && @show_feature_description_in_list
      end

      def disable_fully_enable_message
        if @disable_fully_enable.is_a?(String)
          @disable_fully_enable
        else
          DEFAULT_DISABLE_FULLY_ENABLE_MESSAGE
        end
      end

      def banner_class=(value)
        unless VALID_BANNER_CLASS_VALUES.include?(value)
          raise InvalidConfigurationValue, "The banner_class provided '#{value}' is " \
            "not one of: #{VALID_BANNER_CLASS_VALUES.join(', ')}"
        end
        @banner_class = value
      end
    end
  end
end

View on GitHub (pinned to 1f86de3ec9)

Solutions

1. Use one of the allowed banner classes: danger, dark, info, light, primary, secondary, success, warning
2. Fix the typo in the Flipper::UI banner_class configuration
3. Remove the custom class or extend the allowed list deliberately if you need a custom style

When it happens

Trigger: Thrown at lib/flipper/ui/configuration.rb:156 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of flippercloud/flipper@1f86de3ec9 (2026-08-23). Data as JSON: /api/errors/ed8e351749f25d62. Report an issue: GitHub.