AFNetworking 3.x: How to know whether response is from cache or not?

Question

The question AFNetworking : How to know if response is using cache or not ? 304 or 200 had been answered well for AFNetworking 2.x. But how do you do the same thing in 3.x?

It's very useful to know whether resources were returned from cache or from the network while debugging.

Answer 1

You can follow the same approach with AFNetworking3.0.

 BOOL __block responseFromCache = YES; // yes by default
 [self setDataTaskWillCacheResponseBlock:^NSCachedURLResponse * _Nonnull(NSURLSession * _Nonnull session, NSURLSessionDataTask * _Nonnull dataTask, NSCachedURLResponse * _Nonnull proposedResponse) {
    responseFromCache = NO;
    NSLog(@"Sending back to cache response");
    NSCachedURLResponse * responseCached;
    NSHTTPURLResponse * httpResponse = (NSHTTPURLResponse *)      [proposedResponse response];

    if (dataTask.originalRequest.cachePolicy == NSURLRequestUseProtocolCachePolicy) {
        NSDictionary *headers = httpResponse.allHeaderFields;
        NSString * cacheControl = [headers valueForKey:@"Cache-Control"];
        NSString * expires = [headers valueForKey:@"Expires"];
        if (cacheControl == nil && expires == nil) {
            NSLog(@"Server does not provide info for cache policy");
            responseCached = [[NSCachedURLResponse alloc] initWithResponse:dataTask.response
                                                                      data:proposedResponse.data
                                                                  userInfo:@{ @"response" : dataTask.response, @"proposed" : proposedResponse.data }
                                                             storagePolicy:NSURLCacheStorageAllowed];
        }
    }
    return responseCached;
}];

[self wb_GET:url parameters:nil headerFields:additionalHeadersDict success:^(NSURLSessionDataTask *task, id responseObject) {

        if (responseFromCache) {
            // response was returned from cache
            NSLog(@"RESPONSE FROM CACHE: %@", responseObject);
        }

    handler(responseObject, nil);

} failure:^(NSURLSessionDataTask *task, NSError *error) {
    handler(nil, error);
}];

Besides that you can also implement below delegate method to your AFHTTPSessionManager subclass.

  - (void)baseSuccessWithResponseObject:(id)responseObject sessionTask: (NSURLSessionDataTask *) task validationHandler:(void(^)(id responseObject, NSError *error))handler{}