CC validation

expiry_month_validator.rb

module Validations
  class Validations::ExpiryMonthValidator < ActiveModel::EachValidator

    include ActiveMerchant::Billing::CreditCardMethods

    def validate_each(record, attribute, value)
      record.errors[attribute] << 'is not a valid month' unless record.valid_month?(value)
    end
  end
end
ActiveModel::Validations::ExpiryMonthValidator = Validations::ExpiryMonthValidator