class Goliath::Rack::Validation::RequiredValue

def value_valid?(params)
  if !params.has_key?(key) || params[key].nil? ||
      (params[key].is_a?(String) && params[key] =~ /^\s*$/)
    return false
  end
  if params[key].is_a?(Array)
    return false if params[key].empty?
    params[key].each { |k| return false unless values.include?(k) }
  elsif !values.include?(params[key])
    return false
  end
  true
end