Parse JSON response with AFNetworking

Question

I\'ve setup a JSON post with AFNetworking in Objective-C and am sending data to a server with the following code:

AFHTTPRequestOperationManager          


        

Answer 1

I find it works best to subclass AFHTTPClient like so:

//  MyHTTPClient.h

#import 

@interface MyHTTPClient : AFHTTPClient

+ (instancetype)sharedClient;

@end

//  MyHTTPClient.m

#import "MyHTTPClient.h"

#import 

static NSString *kBaseUrl = @"http://api.blah.com/yada/v1/";

@implementation MyHTTPClient

+ (instancetype)sharedClient {
    static id instance;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        instance = [[self alloc] init];
    });
    return instance;
}

- (id)init {
    if (self = [super initWithBaseURL:[NSURL URLWithString:kBaseUrl]]) {
        self.parameterEncoding = AFJSONParameterEncoding;

        [self setDefaultHeader:@"Accept" value:@"application/json"]; // So AFJSONRequestOperation becomes eligible for requests.
        [self registerHTTPOperationClass:[AFJSONRequestOperation class]]; // So that it gets used for postPath etc.
    }
    return self;
}

@end

The important bits are:

• Setting the 'Accept' in such a way that AFJSONRequestOperation becomes eligible.
• Adding AFJSONRequestOperation to the http operation classes.

Then you can use it like so:

#import "MyHTTPClient.h"

@implementation UserService

+ (void)createUserWithEmail:(NSString *)email completion:(CreateUserCompletion)completion {
    NSDictionary *params = @{@"email": email};
    [[MyHTTPClient sharedClient] postPath:@"user" parameters:params success:^(AFHTTPRequestOperation *operation, NSDictionary *responseObject) {
        completion([responseObject[@"userId"] intValue], YES);
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        completion(0, NO);
    }];
}

@end

The beauty of this is that your responseObject is automatically JSON-parsed into a dictionary (or array) for you. Very clean.

(this is for afnetworking 1.x)