1. the project uses AFNetworking, which has been encapsulated as a tool class. The new version of 20180911 has been updated, and a preliminary study has been made on this

1.1 use case list:

    AFHTTPSessionManager *mgr = [AFHTTPSessionManager manager];
    mgr.requestSerializer = [AFHTTPRequestSerializer serializer];

    NSMutableSet *acceptableSet = [NSMutableSet setWithSet:mgr.responseSerializer.acceptableContentTypes];
    [acceptableSet addObject:@"text/html"];

    AFJSONResponseSerializer *jsonResponse = [AFJSONResponseSerializer serializer];
    jsonResponse.removesKeysWithNullValues = YES;
    jsonResponse.acceptableContentTypes = acceptableSet;
    mgr.responseSerializer = jsonResponse;

    // 2. Send request
    [mgr POST:url parameters:params headers:nil progress:^(NSProgress * _Nonnull uploadProgress) {

    } success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {
        if (success) {
            ResultStatus result = 0;
            if ([responseObject[@"result"] isKindOfClass:[NSString class]]) {   // if result is NSString
                result = empty(responseObject[@"result"]) ? 0 : [responseObject[@"result"] integerValue];
            } else if ([responseObject[@"result"] isKindOfClass:[NSNumber class]]) { // if result is NSNumber
                result = [responseObject[@"result"] intValue] == 1 ? ResultStatusSuccess : ResultStatusFailure;
            }
            success(result, responseObject);
        }
        // Delete circular reference
        [mgr invalidateSessionCancelingTasks:YES];
    } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
        if (failure) {
            failure(error);
        }
        // Delete circular reference
        [mgr invalidateSessionCancelingTasks:YES];
    }];

2. Management Manager:

2.1 inheritance relationship

 AFHTTPSessionManager : AFURLSessionManager : NSObject 

2.2 implementation of agent method:

<NSURLSessionDelegate, NSURLSessionTaskDelegate, NSURLSessionDataDelegate, NSURLSessionDownloadDelegate, NSSecureCoding, NSCopying>

2.3 it mainly uses the AFHTTPSessionManager,

    AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

manager mainly creates a series of default configurations, including thread, request configuration, detail configuration, security configuration, connection configuration, lock and NSURLSession

    if (!configuration) {
        configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
    }

    self.sessionConfiguration = configuration;

    self.operationQueue = [[NSOperationQueue alloc] init];
    self.operationQueue.maxConcurrentOperationCount = 1;

    self.session = [NSURLSession sessionWithConfiguration:self.sessionConfiguration delegate:self delegateQueue:self.operationQueue];

    self.responseSerializer = [AFJSONResponseSerializer serializer];

    self.securityPolicy = [AFSecurityPolicy defaultPolicy];

#if !TARGET_OS_WATCH
    self.reachabilityManager = [AFNetworkReachabilityManager sharedManager];
#endif

    self.mutableTaskDelegatesKeyedByTaskIdentifier = [[NSMutableDictionary alloc] init];

    self.lock = [[NSLock alloc] init];
    self.lock.name = AFURLSessionManagerLockName;

    [self.session getTasksWithCompletionHandler:^(NSArray *dataTasks, NSArray *uploadTasks, NSArray *downloadTasks) {
        for (NSURLSessionDataTask *task in dataTasks) {
            [self addDelegateForDataTask:task uploadProgress:nil downloadProgress:nil completionHandler:nil];
        }

        for (NSURLSessionUploadTask *uploadTask in uploadTasks) {
            [self addDelegateForUploadTask:uploadTask progress:nil completionHandler:nil];
        }

        for (NSURLSessionDownloadTask *downloadTask in downloadTasks) {
            [self addDelegateForDownloadTask:downloadTask progress:nil destination:nil completionHandler:nil];
        }
    }];

2.4 configurable manager requestSerializer and responseSerializer

2.5 manage can directly call post get request method to get data through block

- (nullable NSURLSessionDataTask *)POST:(NSString *)URLString
                             parameters:(nullable id)parameters
                                headers:(nullable NSDictionary <NSString *, NSString *> *)headers
                               progress:(nullable void (^)(NSProgress *uploadProgress))uploadProgress
                                success:(nullable void (^)(NSURLSessionDataTask *task, id _Nullable responseObject))success
                                failure:(nullable void (^)(NSURLSessionDataTask * _Nullable task, NSError *error))failure;

- (nullable NSURLSessionDataTask *)GET:(NSString *)URLString
                            parameters:(nullable id)parameters
                               headers:(nullable NSDictionary <NSString *, NSString *> *)headers
                              progress:(nullable void (^)(NSProgress *downloadProgress))downloadProgress
                               success:(nullable void (^)(NSURLSessionDataTask *task, id _Nullable responseObject))success
                               failure:(nullable void (^)(NSURLSessionDataTask * _Nullable task, NSError *error))failure;

Use NSMutableURLRequest for post request

NSMutableURLRequest *request = [self.requestSerializer multipartFormRequestWithMethod:@"POST" URLString:[[NSURL URLWithString:URLString relativeToURL:self.baseURL] absoluteString] parameters:parameters constructingBodyWithBlock:block error:&serializationError];

post request return data processing

    __block NSURLSessionDataTask *task = [self uploadTaskWithStreamedRequest:request progress:uploadProgress completionHandler:^(NSURLResponse * __unused response, id responseObject, NSError *error) {
        if (error) {
            if (failure) {
                failure(task, error);
            }
        } else {
            if (success) {
                success(task, responseObject);
            }
        }
    }];