Login in a user using AFNetworking 2 (or some other framework - afnetworking-2

Question

I am trying to write some code to have a user enter their username and password and then authenticate against a server using basic HTTP authentication. I can do it using AFNetworking 2 BUT I want to be able to return whether or not the request was successful. The code below works, but how can I refactor it so that I can call the method and then return a BOOL true or false?? It is driving me crazy that I can't do this.
- (void)authenticateWithUserEmail:(NSString *)pUserEmail
withUserPassword:(NSString *)pUserPassword {
NSString *loginURL =
#"https://mydomain/login";
AFHTTPRequestOperationManager *manager =
[AFHTTPRequestOperationManager manager];
manager.requestSerializer = [AFJSONRequestSerializer serializer];
[manager.requestSerializer
setAuthorizationHeaderFieldWithUsername:pUserEmail
password:pUserPassword];
manager.responseSerializer = [AFJSONResponseSerializer serializer];
AFHTTPRequestOperation *operation = [manager GET:loginURL
parameters:[self jsonDict]
success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"Success");
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Failure");
}];
[operation start];
}
- (IBAction)btnAuthenticate:(id)sender {
[self authenticateWithUserEmail:self.userEmail.text
withUserPassword:self.userPassword.text];
}

Answer 1

Because the network call is performed asynchronously, you can't simply return a BOOL because the method returns as soon as you call [operation start];, at which point the network call hasn't completed. What you need to do is add a block parameter to your method that get's invoked in the completion or failure block of the AFHTTPRequestOperation So your method signature will look like this:
- (void)authenticateWithUserEmail:(NSString *)pUserEmail
withUserPassword:(NSString *)pUserPassword
completion:(void (^)(BOOL success))completionBlock;
In this method, add to your success/failure blocks to invoke your new block parameter. Like so:
AFHTTPRequestOperation *operation = [manager GET:loginURL
parameters:[self jsonDict]
success:^(AFHTTPRequestOperation *operation, id responseObject) {
if (completionBlock) {
completionBlock(YES);
}
NSLog(#"Success");
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
if (completionBlock) {
completionBlock(NO);
}
NSLog(#"Failure");
}];
And your invocation of this method will now look like this:
- (IBAction)btnAuthenticate:(id)sender {
[self authenticateWithUserEmail:self.userEmail.text
withUserPassword:self.userPassword.text
completion:^(BOOL success) {
if (success) {
//login successful, do stuff
} else {
//login failed, do other stuff
}
}];
}
This generally how to handle responding to asynchronous events, since you can't return something that hasn't been determined yet.