AFJSONRequestOperation / AFHTTPClient fetching old data - ios

Question

So all I'm trying to do is serve up a .json file somewhere (I've tried both my own personal server, and also on AppFog), then performing a GET request using AFJSONRequestOperation on the iOS platform. My code to do this request is as follows:
AFHTTPClient *aclient = [[AFHTTPClient alloc] initWithBaseURL:[NSURL URLWithString:kBaseURL]];
NSURLRequest *request = [aclient requestWithMethod:#"GET"
path:#"voucher.json"
parameters:nil];
AFJSONRequestOperation *op = [[AFJSONRequestOperation alloc] initWithRequest:request];
[op setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"%#", (NSString *)responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
[op start];
The problem here is that say the .json file initially contained an array of 2 strings. The above code would fetch these objects just fine. Then if I edited the .json file with another 3 strings, rerunning the code would continue to fetch only the 2 old strings.
Only 10-15 minutes after I made the change to the .json file will a refresh give me the updated data. At first I thought this was a caching issue, but setting [client setCachingPolicy:] didn't make any difference.
This issue is present whether I host my .json file on my static server, or running in a Node express server on AppFog. It just keeps returning an old version of the resource requested.
I'm really puzzled about this: so any help would be greatly appreciated!

Answer 1

Make sure the url request is not cacheing the data. I had to implement the following so I would get new json data each time a fetch was made.
NSURLRequest *request = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:5];

Answer 2

This is likely a caching issue - you could change the cache policy on the request or append something onto the query string, like the current time.
To do this you could use something like:
[aclient requestWithMethod:#"GET"
path:[NSString stringWithFormat:#"voucher.json?%#", [NSDate date]]
parameters:nil];