如何使用jquery从cloudify rest api读取json响应？

Question

i need to fetch json data from cloudify rest url (remotehost) http://hostname:8100/service/applications/ .

This URL returns the following JSON response:

{
    "response": {
        "petclinic": ""
    },
    "status": "success"
}

I've tried to get the response with the code below:

$.getJSON("http://hostname:8100/service/applications?jsoncallback=?", function (result) {
    $.each(result, function (i, field) {
        $("div").append(field + " ");
    });
});

I checked request from net panel in firebug, which is showing a 200 OK status, but I can't get the JSON data. The error bellow appears in the console:

Answer 1

Same Origin

Assuming the call is made from the same domain (eg you're deploying a local cloud , and your call is made locally, and sends a request to localhost:8100 ), you should be able to succeed performing REST calls, provided that you remove the ?jsoncallback=? from the request URL.

This suffix to the URL serves to request a wrapper function on the response, and is used with JSONP (JavaScript-Object-Notation Padding) type requests. In order to use JSONP the server must support it - which currently the Cloudify REST API does not - thus such requests will fail, from any origin.

Cross Origin

If you're trying to run this from a different domain than that of the REST server, it won't work regardless. The REST API does not allow for Cross Origin Resource Sharing either. It is meant for use by servers, so create a service that makes the calls to the REST API and serve your client with that. You can than put your jQuery XHR calls on that client, calling your own service.

Further reading

• JSON to JSONP: Bypass Same Origin Policy on codeproject.com
• HTTP Access Control on Mozilla Developer Network
• The Cloudify docs on clodifysource.org