require "rss/1.0" module RSS SY_PREFIX = 'sy' SY_URI = "http://purl.org/rss/1.0/modules/syndication/" RDF.install_ns(SY_PREFIX, SY_URI) module SyndicationModel extend BaseModel ELEMENTS = [] def self.append_features(klass) super klass.module_eval(<<-EOC) %w(updatePeriod updateFrequency).each do |x| install_text_element("\#{SY_PREFIX}_\#{x}") end %w(updateBase).each do |x| install_date_element("\#{SY_PREFIX}_\#{x}", 'w3cdtf', x) end alias_method(:_sy_updatePeriod=, :sy_updatePeriod=) def sy_updatePeriod=(new_value) new_value = new_value.strip validate_sy_updatePeriod(new_value) if @do_validate self._sy_updatePeriod = new_value end alias_method(:_sy_updateFrequency=, :sy_updateFrequency=) def sy_updateFrequency=(new_value) new_value = new_value.strip validate_sy_updateFrequency(new_value) if @do_validate self._sy_updateFrequency = new_value.to_i end EOC end def sy_validate(tags) counter = {} ELEMENTS.each do |x| counter[x] = 0 end tags.each do |tag| key = "#{SY_PREFIX}_#{tag}" raise UnknownTagError.new(tag, SY_URI) unless counter.has_key?(key) counter[key] += 1 raise TooMuchTagError.new(tag, tag_name) if counter[key] > 1 end end private SY_UPDATEPERIOD_AVAILABLE_VALUES = %w(hourly daily weekly monthly yearly) def validate_sy_updatePeriod(value) unless SY_UPDATEPERIOD_AVAILABLE_VALUES.include?(value) raise NotAvailableValueError.new("updatePeriod", value) end end SY_UPDATEFREQUENCY_AVAILABLE_RE = /\A\s*\+?\d+\s*\z/ def validate_sy_updateFrequency(value) if SY_UPDATEFREQUENCY_AVAILABLE_RE !~ value raise NotAvailableValueError.new("updateFrequency", value) end end end class RDF class Channel; include SyndicationModel; end end prefix_size = SY_PREFIX.size + 1 SyndicationModel::ELEMENTS.uniq! SyndicationModel::ELEMENTS.each do |x| BaseListener.install_get_text_element(x[prefix_size..-1], SY_URI, "#{x}=") end end