Question

I need to parse a xml document in ruby, using rexml, that has the following structure:

<events>
    <event>
        <title>Best NYC New Year's Party</title>
        <description>Come spend New Year's Eve with us!</description>
        <category>conferences</category>
        <tags>new year, party</tags>
        <start_date>2008-12-31 20:00:00</start_date>
        <end_date>2009-01-01 06:00:00</end_date>
        <venue>
            <name>Madison Square Garden</name>
            <address>4 Penn Plaza</address>
            <city>New York</city>
            <country>United States</country>
        </venue>
    </event>
</events>

I use this code to get the title and description elements:

doc_xml.elements.each("events/event") do |element|
      event = Event.new
      event.title = element.elements["title"].text
      event.description = element.elements["description"].text

I tried event.address = element.elements["venue"].elements["address"] but I get undefined method `elements’ for nil:NilClass.

But how can I access name element inside venue element?

Answer 1

try this

event.address = element.elements["venue"].elements["address"].text unless element.elements["venue"].elements["address"].nil?

because you should only use the text method if “venue” has an element “address”, otherwise nil is returned.

you can get the “name” element in the same way:

event.name = element.elements["venue"].elements["name"].text unless element.elements["venue"].elements["name"].nil?

if you have to do more complex things with the XML, I recommend using a parser like nokogiri