app/validators/html_validator.rb

   1 # frozen_string_literal: true
   2
   3 class HtmlValidator < ActiveModel::EachValidator
   4   def validate_each(record, attribute, value)
   5     return if value.blank?
   6     record.errors.add(attribute, I18n.t('html_validator.invalid_markup')) unless valid_html?(value)
   7   end
   8
   9   private
  10
  11   def valid_html?(str)
  12     Nokogiri::HTML.fragment(str).to_s == str
  13   end
  14 end