javascript cross domain document.getElementById

Question

I'm trying to open the zip code lookup page on the usps website and fill out the form using javascript, and I get the following error: 'Permission denied to get property Window.document'

Here's my script:

function lookupZipCode(line1, line2, city, state, zip) {
  var usps = window.open('http://zip4.usps.com/zip4/welcome.jsp');
  usps.document.getElementById('address2').value = line1;
  usps.document.getElementById('address1').value = line2;
  usps.document.getElementById('city').value = city;
  usps.document.getElementById('state').value = state;
  usps.document.getElementById('zip5').value = zip);
}

I understand that this is a security feature. Ideally I would use query string params but the page does not appear to support them.

Anyone have any ideas for a workaround?

Answer 1

You should be using the APIs they provide instead of trying to automate filling in a form.

Answer 2

If you don't like the API (;-)), you can use the query-string params: http://zip4.usps.com/zip4/welcome.jsp?address1=somethingelse&address2=something&state=FL&city=Miami&zip5=123456789&urbanization=

Answer 3

It would be helpful to know about the security error you received. It's a result of the "same origin policy" for web scripting.

Answer 4

I havent worked with it too much but you could use the HTML selector in Yahoo Query language (http://developer.yahoo.com/yql/) to get the parts you need. you can then pass it along as JSON which you can get cross domain.