Question

been stuck with an issue for sometime and not getting the best solution for this yet.
I am calling an xmlhttprequest (POST)from a javascript residing at server say ‘http://localhost:8080’ to another server ‘http://localhost:9090’

Getting an browser error As mentioned below:
Exception… “Component returned failure code: 0x80004005 (NS_ERROR_FAILURE)”  nsresult: “0x80004005 (NS_ERROR_FAILURE)” 
 
The error doesnt point anything specific either. Did test the same by calling from same server and worked fine. But i am looking at two server architecture.

Any resolution/ideas ? Saw few posts on setting response headers with cross domain origin as ‘*’,but not sure exactly how to set response headers for xmlhhtprequest calls?

Answer 1

Since the origins of the entities that are trying to communicate are the same in the host part but different in the port part (localhost:8080 <-> localhost:9090) — this violates the same origin policy and the browser throws an error. See this for more info: http://en.wikipedia.org/wiki/Same_origin_policy

The way to get around this is to use CORS headers in the HTTP responses returned by the server. The fact that you are using XHR to generate the HTTP requests makes no difference. Basically, what you need to do is add a Access-Control-Allow-Origin: * or Access-Control-Allow-Origin: http://localhost:8080 to your responses for POST requests to http://localhost:9090. This of course assumes that you have control over the server resource you are POSTing to so that you can modify the response headers. See this for more info: http://enable-cors.org/ and http://en.wikipedia.org/wiki/Cross-Origin_Resource_Sharing