Post request response is not saved in afnetworking 2.0 - ios

Question

I am having problems in saving a response coming from a POST request.
Based on AFnetworking documentation and NSScreencast tutorial I created my own subclass of AFHTTPRequestOperationManager, but I am not sure why the response is not saved.
How do I know, the response is not saved?
Because there is an error:(null) message in console and the my method does not perform segue.
I know that I am getting the values, because of the breakpoint that I put NSURLSessionDataTask
But I do not know why the values are not saved and I am getting an error message. I appreciate any help.
The APIClient/Manager
AuthAPIManager.h
#import "AFHTTPSessionManager.h"
#interface AuthAPIManager : AFHTTPSessionManager
+(AuthAPIManager *)sharedManager;
-(NSURLSessionDataTask *)initializeLogin:(NSString *)username completion:(void(^)(NSDictionary *results, NSError *error))completion;
//for login
#property (nonatomic,readonly,retain)NSString *StoreIdentifierForVendor;
#property(nonatomic,copy)NSString *devicetype;
#end
AuthAPIManager.m
#import "AuthAPIManager.h"
#import "LoginInfo.h"
#import "CredentialStore.h"
static AuthAPIManager *sharedManager =nil;
static dispatch_once_t onceToken;
#implementation AuthAPIManager
+(AuthAPIManager *)sharedManager
{
dispatch_once(&onceToken, ^{
sharedManager = [[AuthAPIManager alloc] initWithBaseURL:[NSURL URLWithString:BASE_URL]];
sharedManager.responseSerializer=[AFJSONResponseSerializer serializer];
sharedManager.requestSerializer = [AFJSONRequestSerializer serializer];
});
return sharedManager;
}
-(id)initWithBaseURL:(NSURL *)url
{
self = [super initWithBaseURL:url];
if (self) {
}
return self;
}
-(NSURLSessionDataTask *)initializeLogin:(NSString *)username completion:(void (^)(NSDictionary *, NSError *))completion
{
_devicetype = #"ios";
_StoreIdentifierForVendor = [[[UIDevice currentDevice]identifierForVendor]UUIDString];
id loginParameters =#{#"AccountId":username,
#"DeviceType":_devicetype
};
NSURLSessionDataTask *task =[self POST:#"/Accn" parameters:loginParameters
success:^(NSURLSessionDataTask *task, id responseObject)
{
NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)task.response;
if (httpResponse.statusCode == 200) {
LoginInfo *loginInfo =[[LoginInfo alloc]initWithDictionary:responseObject];
CredentialStore *credStore =[CredentialStore sharedStore];
credStore.loginInfo =loginInfo;
completion(responseObject,nil);
loginInfo = responseObject;
} else {
dispatch_async(dispatch_get_main_queue(), ^{
completion(nil, nil);
});
NSLog(#"Received: %#", responseObject);
NSLog(#"Received HTTP %d", httpResponse.statusCode);
}
} failure:^(NSURLSessionDataTask *task, NSError *error) {
dispatch_async(dispatch_get_main_queue(), ^{
completion(nil, error);
});
}];
return task;
}
#end
And this is how I am calling my method in my view controller
- (IBAction)login:(id)sender
{
[_usernameTextField resignFirstResponder];
[SVProgressHUD show];
NSURLSessionDataTask *task = [[AuthAPIManager sharedManager] initializeLogin:self.usernameTextField.text completion:^(NSDictionary *results, NSError *error)
{
if (results) {
LoginInfo *loginInfo = [[LoginInfo alloc]initWithDictionary:results];
CredentialStore *credStore =[ CredentialStore sharedStore];
credStore.loginInfo =loginInfo;
[self performSegueWithIdentifier:#"welcomeViewSegue" sender:self];
}
else
{
NSLog(#"there is an error:%#",error);
}
}];
[SVProgressHUD dismiss];
}

Answer 1

Your success block is being called, but your status code is not 200.
You are calling your completion block like this:
completion(nil, nil);
So this code:
if (results) {
[snip]
}
else
{
NSLog(#"there is an error:%#",error);
}
is passed a nil results object.
Set a breakpoint on if (httpResponse.statusCode == 200) and inspect httpResponse in your debugger to see why it's not what you expect. (You may get a different success code, such as 204.)
Call your completion block with results instead of nil.