Using newFetchPersonAppDataRequest on MySpace

Storing application data on the OpenSocial host is a great way to offload some unnecessary database and application server load. Why request a preference such as a skin for a user profile from your servers if we can just let the container handle it? MySpace allows for ~1K of data storage per user per application. However, there is a bug with the method newFetchPersonAppDataRequest when added as the only item of a DataRequest. Calling send on the request doesn’t actually do anything! It returns a DataResponse object with no data. As a work around, grab some other information to ensure that the request actually is sent to the container’s server. I used the owner data in this example.

// The function to load the application data
function getAppData(){
	var req = opensocial.newDataRequest();
	var owner = opensocial.newIdSpec({"userId":"OWNER"});
	req.add(req.newFetchPersonRequest(owner), "owner");
	req.add(req.newFetchPersonAppDataRequest(owner, "appdata"), "owner_appdata");
	req.send(getAppDataCallback);
	return;
}
 
// The callback for getAppData()
function getAppDataCallback(d){
	var owner = d.get("owner"); // if you need it, use it!
	var data = d.get("owner_appdata");
	if(data.hadError()){
		// handle the error appropriately
		return;
	}
	// do whatever your program needs to do with the data
}