Untraceable AFNetworking memory leak - ios

Question

TL;DR : Clone and check leak yourself https://github.com/JakubMazur/SO41343532/
I have a one class that handle all my networking. It's called ResponseOrganizer and in there I have a class method:
+ (void)getSth:(void (^)(NSURLSessionDataTask *operation, NSArray *locales, id plainObject))success failure:(void (^)(NSURLSessionDataTask *operation, NSError *error))failure {
Connection *connection = [Connection new];
connection.urlString = #"http://sample-file.bazadanni.com/download/txt/json/sample.json";
connection.requestMethodType = GET;
[connection fireWithSuccess:^(NSURLSessionDataTask *operation, NSArray *returnArray, id originalResponse) {
success(operation, returnArray, originalResponse);
} failure:^(NSURLSessionDataTask *operation, NSError *error) {
failure(operation, error);
}];
}
Where Connection is a single my internal connection object:
Here is the implementation:
#import "Connection.h"
#interface Connection()
#property (weak,nonatomic) AFHTTPSessionManager *manager;
#end
#implementation Connection
#pragma mark - Connection groundwork
-(void)fireWithSuccess:(void (^)(NSURLSessionDataTask *operation, NSArray* returnArray, id originalResponse))success failure:(void (^)(NSURLSessionDataTask *operation, NSError *error))failure {
self.manager = [AFHTTPSessionManager manager];
[self.manager urlString:self.urlString withMethod:self.requestMethodType parameters:self.paramaters success:^(NSURLSessionDataTask *operation, id responseObject) {
success(operation,#[responseObject],nil);
} failure:^(NSURLSessionDataTask *operation, NSError *error) {
failure(operation,error);
}];
}
#end
And I have a category calling right method inside AFNetworking. To simplify it look like this:
-(void)urlString:(NSString*)urlString withMethod:(RequestMethodType)method parameters:(NSDictionary*)parameters success:(void (^)(NSURLSessionDataTask *operation, id responseObject))success failure:(void (^)(NSURLSessionDataTask *operation, NSError *error))failure {
switch (method) {
case GET: {
[self getWithURLString:urlString parameters:parameters success:^(NSURLSessionDataTask *operation, id responseObject) {
success(operation,responseObject);
} failure:^(NSURLSessionDataTask *operation, NSError *error) {
failure(operation,error);
}];
break;
}
}
And when I want to make request for example in my ViewController I make it like this:
[ResponseOrginizer getSth:^(NSURLSessionDataTask *operation, NSArray *locales, id plainObject) {
} failure:^(NSURLSessionDataTask *operation, NSError *error) {
}];
And when I run it in instrument I'm always getting:
And it here doesn't matter it will land on success/failure block, it always cause a leak. I extract everything from this and put it on github as simple as possible. Github link:
https://github.com/JakubMazur/SO41343532/

Answer 1

The leak appears here:
AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
It seems that the reason is the same (or similar) as discussed here - NSURLSession holds a retained reference to the delegate.
Change you code in Connection.m like this to avoid the leak:
-(void)fireWithSuccess:(void (^)(NSURLSessionDataTask *operation, NSArray* returnArray, id originalResponse))success failure:(void (^)(NSURLSessionDataTask *operation, NSError *error))failure {
AFHTTPSessionManager *manager = [Connection manager];
[manager urlString:self.urlString withMethod:self.requestMethodType parameters:self.paramaters success:^(NSURLSessionDataTask *operation, id responseObject) {
success(operation,#[responseObject],nil);
} failure:^(NSURLSessionDataTask *operation, NSError *error) {
failure(operation,error);
}];
}
+ (AFHTTPSessionManager*) manager
{
static dispatch_once_t onceToken;
static AFHTTPSessionManager *manager = nil;
dispatch_once(&onceToken, ^{
manager = [AFHTTPSessionManager manager];
});
return manager;
}
If you need to handle multiple sessions, you may use another approach: call -[AFHTTPSessionManager invalidateSessionCancelingTasks:] when you're done with the session, e.g.:
-(void)fireWithSuccess:(void (^)(NSURLSessionDataTask *operation, NSArray* returnArray, id originalResponse))success failure:(void (^)(NSURLSessionDataTask *operation, NSError *error))failure {
AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
[manager urlString:self.urlString withMethod:self.requestMethodType parameters:self.paramaters success:^(NSURLSessionDataTask *operation, id responseObject) {
success(operation,#[responseObject],nil);
[manager invalidateSessionCancelingTasks:YES];
} failure:^(NSURLSessionDataTask *operation, NSError *error) {
failure(operation,error);
[manager invalidateSessionCancelingTasks:YES];
}];
}
(Note: pass YES if you want to cancel pending tasks, NO otherwise).