Parse XML Libxmljs (Node.js)
libxmljs supports DOM as well as SAX style parsing.
var xmlDoc = libxmljs.parseXmlString('<item><data id="firstName">Your Name</data></item>');var xmlDoc2 = libxmljs.parseXmlFile('mydata.xml');
The API is custom and doesn't follow the W3C/browser spec (it's on my list). You will want to use xpath to query the document for the content you want.
xmlDoc.find("//[@id='firstName']")[0].childNodes()[0].text()
Notice that childNodes and text are function calls. Take a look at the docs.
https://github.com/polotek/libxmljs/wiki/Element
As far as I know, libxmljs and jsdom are the two libraries that have decent DOM implementations.