RE: [xml-dev] Maximally Consumable Data

["Costello, Roger L." <costello@mitre.org>]

Hi Mukul,

> IMHO, what's different (great) about this scenario?

I need to give more detail about how it works.

A JavaScript Ajax application that is running in a browser can only
fetch data from the domain that it came from.  It does this using the
XMLHttpRequest object.

Quoting now from Bulletproof Ajax: 

"We can't use XMLHttpRequest to access the Web APIs offered by so many
sites these days.  That's a real shame because most APIs return their
data in XML, which would be available in responseXML.  

The script element has no such security restrictions.  It's possible to
access a JavaScript file from another domain in this way:

<script type="text/javascript"
 
src="http://www.xfront.com/us_states/json/javascript/us_states.js";></sc
ript>

If you can request a JavaScript file from another domain, then you can
also request a JSON file.  Remember, JSON is nothing more than
JavaScript."

-- the author shows how this can be generated dynamically --

Thus, through this technique, the JavaScript running in your browser
can pull in data from any web service that serves up JSON (such as the
Yahoo web services).

/Roger