Serialize a `Document` to a XML string.

serialize-to-xml.js

/**
 * Serialize a document to a string the hard way (using lodash)
 * @param {Document} xml
 * @return {String}
 */
function documentToXmlString(xml) {
  var xmlString = "";

  function serialize(xmlDoc) {
    _.forEach(xmlDoc.childNodes, function (el) {
      if (el.nodeType == Node.TEXT_NODE) {
        xmlString += _.escape(el.textContent);
        return;
      }

      xmlString += "<" + el.nodeName;  // Open tag

      // Loop over the attributes and append them
      _.forEach(el.attributes,  function(attribute) {
        xmlString += " " + attribute.name + '="' + _.escape(attribute.value) + '"';
      });

      if (el.hasChildNodes()) {
        // If there are child nodes, loop over them recursively
        xmlString += ">";
        serialize(el);
        xmlString += "</" + el.nodeName + ">";
      }
      else {
        // No child nodes, use a self-closing tag
        xmlString += '/>';
      }
    });
  }

  return serialize(xml);
}