AFNetworking: getPath:parameters-method causes an issue - ios

Question

I´m trying to do a GET request to my web service, using AFNetworking(great framework). This is the code for the request:
AFHTTPClient *httpClient = [[AFHTTPClient alloc]initWithBaseURL:[NSURL URLWithString:#"http://mywebservice.com/service/"]];
[httpClient setParameterEncoding:AFJSONParameterEncoding];
[httpClient registerHTTPOperationClass:[AFJSONRequestOperation class]];
NSMutableURLRequest *request = [httpClient getPath:#"http://mywebservice.com/service/contacts"
parameters:#{#"accessID":self.accessId, #"name":contactName}
success:^(AFHTTPRequestOperation *operation, id responseObject) {
//Success code
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
//Error code
}];
This causes the following issue to appear(pointing at my NSMutableURLRequest instance):
Initializing 'NSMutableURLRequest *__strong' with an expression of incompatible type 'void'
I have no idea what causes this, so any help would be appreciated.

Answer 1

This method on AFHTTPClient:
-(void)getPath:parameters:success:failure:
returns nothing (void) and you are trying to assign it to a variable.
NSMutableURLRequest *request = [httpClient getPath:....
This is all the information we need to interpret your error message:
Initializing 'NSMutableURLRequest *__strong' with an expression of incompatible type 'void'
You declare a variable, request, and you type it as NSMutableURLRequest *. For memory management ARC adds the memory semantic __strong. The full type of your variable is `NSMutableURLRequest *__strong. You then attempt to assign, =, the result of the method -(void)getPath:parameters:success:failure: to that variable. The method returns nothing, otherwise known as void. void and NSMutableRequest * are not the same type so the compiler complains with the above error message.
This method actually starts performing the request when you call it. The results are supplied as parameters to the completion or failure block, which are executed when the HTTP request completes. This would be the correct way to perform the HTTP request you are trying to send:
[httpClient getPath:#"contacts"
parameters:#{#"accessID":self.accessId, #"name":contactName}
success:^(AFHTTPRequestOperation *operation, id responseObject) {
//Success code
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
//Error code
}];
Notice how this is not assigned to a variable. Also when using these path methods on AFHTTPClient we dont need to include the baseURL, only the parts of the path we want to append on to it.