在iframe中解析xml

Question

I want to be able access an rss feed from js. I have the ability to configure both servers to use the same domain (but different subdomains - eg static.benanderson.us and tech.benanderson.us). I was hoping I could use the document.domain property to get around the xss issue. Here's a snippet http://static.benanderson.us/example.js (not actually live):

document.domain = 'benanderson.us';
new Ajax.Request('http://tech.benanderson.us/feeds/posts/default', { \\error

However, that doesn't work. I couldn't find out if document.domain works for xhr requests, so I bagged that and switched to an iframe solution because I've done something similar in the past.

$('my_iframe').src='http://tech.benanderson.us/feeds/posts/default';
Event.observe($('my_iframe'), 'load', function() {
  try {
    log(this.contentDocument);  //this displays just fine
    var entries = this.contentDocument.getElementsByTagName('entry');  //error

The weird thing is that I can view this.contentDocument in firebug, however it's the getElementsByTagName that errors with a "permission denied..." message.

Any thoughts on how to get either of these solutions to work would be awesome. I know I could do a proxy - that's not what I'm interested in.

Answer 1

You cant do that, it is not allowed by same origin policy

You can only set document.domain to the superdomain of the current domain, you do that but the same origin policy has to match the whole domain name that it is allowed (tech.benanderson.us != benanderson.us)