Get NSURLSessionDataTask In Intercepted Completion Handler

Question

I'm using AFNetworking and I am overridding -dataTaskWithRequest:completionHandler: to basically MITM my request and do some error handling prior to calling the actual response block. However, I need access to the NSURLSessionDataTask object that the -dataTaskWithRequest:completionHandler: method creates, inside my intercepted completion handler. So my override of the method looks like this:

-(NSURLSessionDataTask *)dataTaskWithRequest:(NSURLRequest *)request completionHandler:(void (^)(NSURLResponse *, id, NSError *))completionHandler {

    void (^interceptedCompletionHandler)(NSURLResponse *, id, NSError *) = ^void(NSURLResponse * response, id responseObject, NSError * error) {
        if (error) {
            // Do custom stuff here that needs to use task.taskIdentifier
        }

        // Then call the original completion handler
        completionHandler(response, responseObject, error);

    }

    return [super dataTaskWithRequest:request completionHandler:interceptedCompletionHandler];
}

Is this possible?

I know that AFNetworking could add this quite easily as the response parameter of the completion handler is set as task.response in AFURLSessionManager , which is the class that contains the -URLSession:task:didCompleteWithError: that calls the completion handler.

Answer 1

I've figured it out. By declaring the block inline and assigning the super call to a variable, I'm able to use the resulting task object:

-(NSURLSessionDataTask *)dataTaskWithRequest:(NSURLRequest *)request completionHandler:(void (^)(NSURLResponse *, id, NSError *))completionHandler {

    __block NSURLSessionDataTask* task = [super dataTaskWithRequest:request completionHandler:
                                      ^void(NSURLResponse * response, id responseObject, NSError * error)
    {
        // I can use task here
        if (error) {
            // Do custom stuff here that needs to use task.taskIdentifier
        }

        // Then call the original completion handler
        completionHandler(response, responseObject, error);

    }

    return task;
}