Cross-Origin resource sharing and file://

Question

I am writing an HTML5 application that is gathering data from a few different sources using JSONP. Anything I\'m doing with a GET works perfectly. I\'m now trying to POST

Answer 1

As it would turn out, the easiest way to do this is to post to the target url inside of an iframe. Same origin policy on most browsers allows you to perform an HTTP POST from one domain to another unrelated domain. I solved the problem by adding an iframe to my page, initially set to a local bootstrapping page. Since that page was loaded from the same domain, I am able to control it via script. I used that to post the form to my target site, and polled the results to determine if my call was successful. It's not elegant, but it works.

Answer 2

This Javascript library can almost certainly help you:

http://easyxdm.net/

easyXDM is a Javascript library that enables you as a developer to easily work around the limitation set in place by the Same Origin Policy, in turn making it easy to communicate and expose javascript API’s across domain boundaries.

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At the core easyXDM provides a transport stack capable of passing string based messages between two windows, a consumer (the main document) and a provider (a document included using an iframe). It does this by using one of several available techniques, always selecting the most efficient one for the current browser. For all implementations the transport stack offers bi-directionality, reliability, queueing and sender-verification.