Objective-C – ASIHTTPRequest caches even if new content is available

I'm using ASIHTTPRequest to download data from the internet. It has a nifty cacheing feature that you can turn on so that it caches the downloaded data. So far so good. But when I upload new data to my webserver and try to download it again I'm expecting it not to use the cache since the data is new and modified. But even so it will still use the cache.

I'm using the following code for my request:

[ASIHTTPRequest setDefaultCache:[ASIDownloadCache sharedCache]];

// When you turn shouldRespectCacheControlHeaders off, the cache will store responses even if the server 
// has explictly asked for them not be be cached (eg with a cache-control or pragma: no-cache header)
[[ASIDownloadCache sharedCache] setShouldRespectCacheControlHeaders:NO];

NSURL *officesUrl = [NSURL URLWithString:@"http://www.example.com/example.json"];
ASIHTTPRequest *officesRequest = [ASIHTTPRequest requestWithURL:officesUrl];

[officesRequest setDefaultResponseEncoding:NSUTF8StringEncoding];

[officesRequest addRequestHeader:@"Cac开发者_开发技巧he-Control" value:@"no-cache"];

// Always ask the server if there is new content available, 
// If the request fails, use data from the cache even if it should have expired.
[officesRequest setCachePolicy:ASIAskServerIfModifiedCachePolicy|ASIFallbackToCacheIfLoadFailsCachePolicy];

[officesRequest setCacheStoragePolicy:ASICachePermanentlyCacheStoragePolicy];

[officesRequest setDelegate:self];

[officesRequest startAsynchronous];

EDIT:

Two images to show the different headers from HTTPScoop. First image is a fresh download with no cached content. Second image I have uploaded new and modified data.

First:

Second:

EDIT2: Added logs

https://gist.github.com/1139351

I was expecting way more debug output than that, I'm not sure why you got so little.

I think you are just going to have to step through the response processing and see why it decides the cached version is okay to use. The code's pretty easy to follow.

Try setting a breakpoint on useDataFromCache in ASIHTTPRequest.m to start with and canUseCachedDataForRequest, particularly when called from readResponseHeaders.