Alamofire请求code=-999

最近在研究RxSwift，用Alamofire请求数据，Alam他默认timeout时间是30s，我想把他改成15s于是就这样:

static func request(N: YYAPI) -> Observable {
        return Observable.create { (obser) -> Disposable in
            let config = URLSessionConfiguration.default
            config.timeoutIntervalForRequest = 15
            let manager = Alamofire.SessionManager(configuration: config)
            manager.request(N.path, method: N.method, parameters: N.param, encoding: URLEncoding.default, headers: nil)
            .responseJSON(completionHandler: { (response) in
                var result = YYResult()
                switch response.result{
                case .success(let value):
                    result.data = value
                    obser.onNext(result)
                case .failure(let error):
                    obser.onError(error)
                }
            })
            return Disposables.create {
                
            }
        }
    }

无论我怎样试结果都是code=-999 cancelled

FAILURE: Error Domain=NSURLErrorDomain Code=-999 "cancelled" UserInfo={NSErrorFailingURLKey=http://sssss/api/api_open.php?a=list&c=data&page=1&type=29, NSLocalizedDescription=cancelled, NSErrorFailingURLStringKey=http://sssss/api/api_open.php?a=list&c=data&page=1&type=29}

于是就翻阅资料才发现，自定义的manager必须是强引用，于是改一下

static var manger:SessionManager? = nil
    static func request(N: YYAPI) -> Observable {
        return Observable.create { (obser) -> Disposable in
            let config = URLSessionConfiguration.default
            config.timeoutIntervalForRequest = 15
            manger = Alamofire.SessionManager(configuration: config)
            manger?.request(N.path, method: N.method, parameters: N.param, encoding: URLEncoding.default, headers: nil)
            .responseJSON(completionHandler: { (response) in
                var result = YYResult()
                switch response.result{
                case .success(let value):
                    result.data = value
                    obser.onNext(result)
                case .failure(let error):
                    obser.onError(error)
                }
            })
            return Disposables.create {
                
            }
        }
    }

这样就能请求成功了
最近在看RxSwift...