Question

I’m trying to read a feed from Yahoo Pipes into a Silverlight Application. I keep getting a SecurityException, which sounds like a cross domain policy problem, but Yahoo pipes, if you go through the pipes.yahooapis domain, has a cross domain policy, so should be ok. I tried the exact same code, but going to the Digg API, and it works fine (although this is rest rather than an rss feed). Could my error have nothing to do with Cross Domain policies?

I use the following code for the web request :

 WebClient wc = new WebClient();      wc.DownloadStringAsyncCompleted += new DownloadStringCompletedEventHandler(wc_DlStrCompleted);      wc.DownloadStringAsync(new Uri(yahooPipesUrl)); 

The exception I get is a System.Security.SecurityException.

The url I’m trying is this one

http://pipes.yahooapis.com/pipes/pipe.run?_id=4rBri9Ef3RG8CEGLLe2fWQ&_render=rss&feedUrl=http://feeds.feedburner.com/follesoe

Answer 1

The policy file in place is:

<!DOCTYPE cross-domain-policy SYSTEM 'http://www.adobe.com/xml/dtds/cross-domain-policy.dtd'>  <cross-domain-policy>    <site-control permitted-cross-domain-policies='master-only' />    <allow-access-from domain='*' />  </cross-domain-policy> 

There is a current problem that Silverlight does not work with the entire Flash Cross Domain Policy file format…I would expect that the site-control element is breaking it.