def validate!
      unless valid?
        sentence = errors.full_messages.join(', ')
        raise Error::InvalidResource.new(errors: sentence)
      end

      true
    end
def validate!
      unless valid?
        sentence = errors.full_messages.join(', ')
        raise Error::InvalidResource.new(errors: sentence)
      end

      true
    end
Run all of this resource's validations, raising an exception if any
 validations fail.

 @raise [Error::InvalidResource]
   if any of the validations fail

 @return [Boolean]
   true if the validation was successful - this method will never return
   anything other than true because an exception is raised if validations
   fail