Parsing multi-level XML with Google App Script XmlService

Question

I'm having trouble getting to the child elements to the <result> tag.

The code:

var xml = '\
  <document>\
    <currentTime>2013-09-05 09:47:06</currentTime>\
    <result>\
      <one>2013-09-05 09:47:06</one>\
      <two>2013-09-20 14:30:13</two>\
      <three>2013-09-02 14:12:22</three>\
      <four>2505</four>\
    </result>\
    <cachedUntil>2013-09-05 10:28:40</cachedUntil>\
  </document>';

var document = XmlService.parse(xml);
var entries = document.getRootElement().getChildren();
Logger.log(entries.length);
for (var i = 0; i < entries.length; i++) {
  Logger.log("%s -> %s",entries[i].getName(),entries[i].getText());
}

Running this code returns the following in the logger as I expected:

[13-09-05 13:54:18:815 EAT] 3.0
[13-09-05 13:54:18:815 EAT] currentTime -> 2013-09-05 09:47:06
[13-09-05 13:54:18:816 EAT] result ->                                       
[13-09-05 13:54:18:816 EAT] cachedUntil -> 2013-09-05 10:28:40

I get 3 elements and I'm able to run the getName() and getText() methods just fine. However, if I try to get the children of a specific element like <result> with the line var results = entries.getChildren(); right after I define entries, I get the runtime error "TypeError: Cannot find function getChildren in object [Element: ]". What the deuce?

I don't get what's going on here (obviously). getRootElement() returns an Element type. getChildren() returns an array of Elements. Where is entries getting turned into something that isn't an Element and is there a better way to parse this document? I feel like I'm missing something really stupid here.

Arun Nagarajan · Accepted Answer · 2013-09-05 13:18:30Z

1

You can only call getChildren() on an element if has children. It depends what you are trying to do, but here is a simple recursive function that will pull what I think you want -

The key check is elements[i].getContentSize() > 1

function startTraversing() {
  var xml = '\
  <document>\
    <currentTime>2013-09-05 09:47:06</currentTime>\
    <result>\
      <one>2013-09-05 09:47:06</one>\
      <two>2013-09-20 14:30:13</two>\
      <three>2013-09-02 14:12:22</three>\
      <four>2505</four>\
    </result>\
    <cachedUntil>2013-09-05 10:28:40</cachedUntil>\
  </document>';

 var document = XmlService.parse(xml); 
 logChildren(document.getRootElement().getChildren());

}

function logChildren(elements){
 Logger.log(elements.length);
 for (var i = 0; i < elements.length; i++) {
  Logger.log("%s -> %s",elements[i].getName(),elements[i].getText());
  if(elements[i].getContentSize() > 1){
    var children = elements[i].getChildren();
    logChildren(children);
  }
 } 
}

This will output -

[13-09-05 09:12:55:781 EDT] 3.0
[13-09-05 09:12:55:781 EDT] currentTime -> 2013-09-05 09:47:06
[13-09-05 09:12:55:782 EDT] result ->                             
[13-09-05 09:12:55:782 EDT] 4.0
[13-09-05 09:12:55:783 EDT] one -> 2013-09-05 09:47:06
[13-09-05 09:12:55:783 EDT] two -> 2013-09-20 14:30:13
[13-09-05 09:12:55:783 EDT] three -> 2013-09-02 14:12:22
[13-09-05 09:12:55:784 EDT] four -> 2505
[13-09-05 09:12:55:784 EDT] cachedUntil -> 2013-09-05 10:28:40

answered Sep 5, 2013 at 13:18

Arun Nagarajan

5,6651 gold badge24 silver badges19 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

mcenhillk Over a year ago

Thanks for your time. It took a while to figure out what I was doing wrong in the first place. getChildren returns and ARRAY of elements. Even a single element is still an array of 1. If I had replaced var results = entries.getChildren(); with var results = entries[0].getChildren(); I get the behavior I was expecting.

Collectives™ on Stack Overflow

Parsing multi-level XML with Google App Script XmlService

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related