Cross-site AJAX requests

Question

I need to make an AJAX request from a website to a REST web service hosted in another domain.

Although this is works just fine in Internet Explorer, other browsers such as Mozilla and Google Chrome impose far stricter security restrictions, which prohibit cross-site AJAX requests.

The problem is that I have no control over the domain nor the web server where the site is hosted. This means that my REST web service must run somewhere else, and I can't put in place any redirection mechanism.

Here is the JavaScript code that makes the asynchronous call:

var serviceUrl = "http://myservicedomain"; var payload = "<myRequest><content>Some content</content></myRequest>"; var request = new XMLHttpRequest(); request.open("POST", serviceUrl, true); // <-- This fails in Mozilla Firefox amongst other browsers request.setRequestHeader("Content-type", "text/xml"); request.send(payload); 

How can I have this work in other browsers beside Internet Explorer?

Answer 1

maybe JSONP can help.

NB youll have to change your messages to use json instead of xml

Edit

Major sites such as flickr and twitter support jsonp with callbacks etc

Answer 2

The post marked as the answer is erroneous: the iframes document is NOT able to access the parent. The same origin policy works both ways.

The fact is that it is not possible in any way to consume a rest based webservice using xmlhttprequest. The only way to load data from a different domain (without any framework) is to use JSONP. Any other solutions demand a serverside proxy located on your own domain, or a client side proxy located on the remote domain and som sort of cross-site communication (like easyXDM) to communicate between the documents.