dispatch_group_tを使用したAFNetworking要求のキュー

Question

キューにメッセージを1つずつ送信したいとします。言い換えれば、私は以前の要求の応答を得た後、新しい要求を送る必要があります。私はdispatch_group_tとAFNetworkingを使用します。しかし、期待通りに動作しません（私はoperationQueueと他の方法があることを知っています）。ここに私のコントローラは次のとおりです。

- (void)viewWillAppear:(BOOL)animated 
{ 
    [super viewWillAppear:animated]; 

    dispatch_async(queue, ^{ 
     [self sentTest]; 
    }); 
} 

- (void) sentTest{ 
    dispatch_group_t group = dispatch_group_create(); 
    NSLog(@"Start ..."); 
    for(int i = 1; i <= 10; i++) 
    { 
     dispatch_group_enter(group); 
     NSLog(@"sending message %d ...", i); 

     NSMutableDictionary *params = [@{@"param1":  @"value1", 
             @"param2":  @"value2", 
             } mutableCopy]; 
     NSString *webServiceUrl = @"MY_REST_SERVICE_URL"; 

     AFHTTPSessionManager *manager = [[AFHTTPSessionManager alloc] init]; 
     manager.responseSerializer = [AFJSONResponseSerializer serializer]; 

     [manager POST:webServiceUrl parameters:params success:^(NSURLSessionDataTask *task, id responseObject) { 
      NSLog(@"message sent successful %d", i); 
      dispatch_group_leave(group); 
     } failure:^(NSURLSessionDataTask *task, NSError *error) { 
      NSLog(@"message sent failure %d", i); 
      dispatch_group_leave(group); 
     }]; 

    } 
    dispatch_group_wait(group, DISPATCH_TIME_FOREVER); 
    NSLog(@"Finished!"); 
} 

結果は以下の通りです：

2016-05-18 14:46:32.350 my_app[24514:29642637] Start ... 
2016-05-18 14:46:32.350 my_app[24514:29642637] sending message 1 ... 
2016-05-18 14:46:32.352 my_app[24514:29642637] sending message 2 ... 
2016-05-18 14:46:32.353 my_app[24514:29642637] sending message 3 ... 
2016-05-18 14:46:32.353 my_app[24514:29642637] sending message 4 ... 
2016-05-18 14:46:32.354 my_app[24514:29642637] sending message 5 ... 
2016-05-18 14:46:32.355 my_app[24514:29642637] sending message 6 ... 
2016-05-18 14:46:32.356 my_app[24514:29642637] sending message 7 ... 
2016-05-18 14:46:32.357 my_app[24514:29642637] sending message 8 ... 
2016-05-18 14:46:32.358 my_app[24514:29642637] sending message 9 ... 
2016-05-18 14:46:32.359 my_app[24514:29642637] sending message 10 ... 
2016-05-18 14:46:33.738 my_app[24514:29642545] message sent successful 1 
2016-05-18 14:46:34.818 my_app[24514:29642545] message sent successful 2 
2016-05-18 14:46:35.833 my_app[24514:29642545] message sent successful 8 
2016-05-18 14:46:36.955 my_app[24514:29642545] message sent successful 5 
2016-05-18 14:46:37.957 my_app[24514:29642545] message sent successful 9 
2016-05-18 14:46:39.017 my_app[24514:29642545] message sent successful 4 
2016-05-18 14:46:40.034 my_app[24514:29642545] message sent successful 3 
2016-05-18 14:46:41.115 my_app[24514:29642545] message sent successful 10 
2016-05-18 14:46:42.233 my_app[24514:29642545] message sent successful 6 
2016-05-18 14:46:43.253 my_app[24514:29642545] message sent successful 7 
2016-05-18 14:46:43.253 my_app[24514:29642637] Finished! 

この問題を解決するためにどのように？

Answer 1

2回目の試行。これは私のために働く。あなたはdispatch_group_waitを間違って配置しました。 forループの先頭に置くとうまくいくはずです。それ以外の場合は、すべてのリクエストが既に途中で待機しています。

- (void)viewDidLoad { 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view, typically from a nib. 

    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); 

    dispatch_async(queue, ^{ 
     [self sendTest]; 
    }); 


} 

- (void) sendTest{ 

    dispatch_group_t group = dispatch_group_create(); 

    NSLog(@"Start ..."); 

    for(int i = 1; i <= 10; i++) 
    { 
     dispatch_group_wait(group, DISPATCH_TIME_FOREVER); 

     dispatch_group_enter(group); 

      NSLog(@"sending message %d ...", i); 

      NSString *webServiceUrl = @"http://ws.audioscrobbler.com/2.0/?method=artist.search&artist=Artist&api_key=c0e97cf5fe59ad032059fb7b2eaab414&format=json"; 

      AFHTTPSessionManager *manager = [[AFHTTPSessionManager alloc] init]; 
      manager.responseSerializer = [AFJSONResponseSerializer serializer]; 



      [manager GET:webServiceUrl parameters:nil progress:^(NSProgress * _Nonnull downloadProgress) { 


     } success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) { 

      NSLog(@"message sent successful %d", i); 

      dispatch_group_leave(group); 

     } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) { 
      NSLog(@"message sent failure %d", i); 

      dispatch_group_leave(group); 

     }]; 

    } 

    NSLog(@"Finished!"); 
} 

Answer 2

sendTestメソッドを繰り返し呼び出すことで、リクエストが完了した後で再帰的に行うことができます。方法はここにあります。コードをテストしていないので、少し修正する必要があります。ご不明な点がありましたらお気軽にお問い合わせください。

- (void)viewDidLoad { 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view, typically from a nib. 

    NSLog(@"Start ..."); 

    [self sentTest:0]; 
} 

- (void) sentTest:(int)i{ 

    if(i >= 10) 
    { 
     NSLog(@"Finished"); 
     return; 
    } 

    NSLog(@"sending message %d ...", i); 

    NSString *webServiceUrl = @"http://ws.audioscrobbler.com/2.0/?method=artist.search&artist=Artist&api_key=c0e97cf5fe59ad032059fb7b2eaab414&format=json"; 

    AFHTTPSessionManager *manager = [[AFHTTPSessionManager alloc] init]; 
    manager.responseSerializer = [AFJSONResponseSerializer serializer]; 

    [manager GET:webServiceUrl parameters:nil progress:^(NSProgress * _Nonnull downloadProgress) { 


    } success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) { 
     NSLog(@"message sent successful %d", i); 

     __block int blockI = i + 1; 

     [self sentTest:blockI]; 

    } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) { 
     NSLog(@"message sent failure %d", i); 

    }]; 

} 

出力：

2016-05-19 10:12:48.460 TestAFNetworking[75972:21147962] Start ... 
2016-05-19 10:12:48.460 TestAFNetworking[75972:21147962] sending message 0 ... 
2016-05-19 10:12:49.014 TestAFNetworking[75972:21147962] message sent successful 0 
2016-05-19 10:12:49.015 TestAFNetworking[75972:21147962] sending message 1 ... 
2016-05-19 10:12:49.524 TestAFNetworking[75972:21147962] message sent successful 1 
2016-05-19 10:12:49.525 TestAFNetworking[75972:21147962] sending message 2 ... 
2016-05-19 10:12:50.126 TestAFNetworking[75972:21147962] message sent successful 2 
2016-05-19 10:12:50.127 TestAFNetworking[75972:21147962] sending message 3 ... 
2016-05-19 10:12:50.637 TestAFNetworking[75972:21147962] message sent successful 3 
2016-05-19 10:12:50.637 TestAFNetworking[75972:21147962] sending message 4 ... 
2016-05-19 10:12:51.477 TestAFNetworking[75972:21147962] message sent successful 4 
2016-05-19 10:12:51.477 TestAFNetworking[75972:21147962] sending message 5 ... 
2016-05-19 10:12:52.257 TestAFNetworking[75972:21147962] message sent successful 5 
2016-05-19 10:12:52.257 TestAFNetworking[75972:21147962] sending message 6 ... 
2016-05-19 10:12:52.595 TestAFNetworking[75972:21147962] message sent successful 6 
2016-05-19 10:12:52.595 TestAFNetworking[75972:21147962] sending message 7 ... 
2016-05-19 10:12:52.937 TestAFNetworking[75972:21147962] message sent successful 7 
2016-05-19 10:12:52.938 TestAFNetworking[75972:21147962] sending message 8 ... 
2016-05-19 10:12:53.540 TestAFNetworking[75972:21147962] message sent successful 8 
2016-05-19 10:12:53.540 TestAFNetworking[75972:21147962] sending message 9 ... 
2016-05-19 10:12:54.043 TestAFNetworking[75972:21147962] message sent successful 9 
2016-05-19 10:12:54.044 TestAFNetworking[75972:21147962] Finished