This example employs the YUI Get Utility in a simple use case: retrieving JSON data from a cross-domain web service. While this is a relatively common usage, it's important to understand the security ramifications of this technique. Scripts loaded via the Get Utility (or any other "script node" solution) execute immediately once they are loaded. If you do not fully control (or fully trust) the script's source, this is not a safe technique and it can put the security of your users' data at risk. (For more information on the dangers of cross-site scripting [XSS] exploits, check out the Wikipedia entry on this subject.)
Here, we will use a trusted Yahoo! Search web service called Site Explorer to return a list of inbound links for a given URL. The principal difference between this example and similar examples using YUI Connection Manager is that this technique does not require a server-side proxy. The browser connects directly to the third-party web service without bouncing through a proxy page as is required when using the XMLHttpRequest object (on which Connection Manager relies).
This example has the following dependencies:
getSiteExplorerData, accomplishes four things:
All YUI 2.x users should review the YUI 2.8.2 security bulletin, which discusses a vulnerability present in YUI 2.4.0-2.8.1.