authentication - urlsessionでプロキシを認証する方法は?

Question

こんにちは、資格情報を使用してプロキシをアプリに追加しようとしていますが、試行するたびに、(Xcode で) 次のコンソール警告が表示されます:

*** WARNING: CFMachPortSetInvalidationCallBack() called on a CFMachPort with a Mach port (0x900b) which does not have any send rights.  This is not going to work.  Callback function: 0x181bcf524

次の説明でアラートも取得しました

Authentication for HTTP proxy
MyProxyHost
MyProxyPort

ポップアップをキャンセルすると、次のメソッドが呼び出されます

func urlSession(_ session: URLSession, task: URLSessionTask, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void)

Xcode コンソールでチャレンジをデバッグし、次の debugDescription を取得しました。

po challenge.protectionSpace.debugDescription
"<NSURLProtectionSpace: 0x12f685ad0>: Host: MyProxyHost, Server:http, Auth-Scheme:NSURLAuthenticationMethodHTTPBasic, Realm:(null), Port: MyProxyPort, Proxy:YES, Proxy-Type:http"

私の質問は、プロキシ認証を処理する方法ですか?

私のコード:

func getURLCredential() -> URLCredential {

        let credential = URLCredential(user: user, password: password, persistence: URLCredential.Persistence.forSession)
        return credential
    }

以下の辞書から、プロキシをヒットできますが、プロキシを認証できません。

// Create an NSURLSessionConfiguration that uses the proxy
    let proxyDict: [AnyHashable: Any]? = [(kCFNetworkProxiesHTTPEnable as AnyHashable): Int(1), (kCFNetworkProxiesHTTPProxy as AnyHashable): proxyServerString, (kCFNetworkProxiesHTTPPort as AnyHashable): proxyPortNumber, (kCFProxyUsernameKey as AnyHashable): userNameKey, (kCFProxyPasswordKey as AnyHashable): password]
    let configuration = URLSessionConfiguration.default
    configuration.connectionProxyDictionary = proxyDict

以下の方法をいくつか試しましたが失敗しました：

let loginString = String(format: "%@:%@", user, password)
        let loginData = loginString.data(using: String.Encoding.utf8)!
        let base64LoginString = loginData.base64EncodedString()// base64EncodedData(options: [])
configuration.httpAdditionalHeaders = ["Authorization" : base64LoginString]

別の方法：

let protectionSpace:URLProtectionSpace = URLProtectionSpace(host: proxyHost, port: proxyPort, protocol: "http", realm: nil, authenticationMethod: NSURLAuthenticationMethodHTTPBasic)
        let credentialStorage = URLCredentialStorage.shared//.allCredentials

        credentialStorage.set(getURLCredential(), for: protectionSpace)
        configuration.urlCredentialStorage = credentialStorage

別の方法：

func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        print("Challenge:")

        guard challenge.previousFailureCount == 0 else {
            print("Previous Failure Count = \(challenge.previousFailureCount)")
            print("Cancelling Challenge\n")
            challenge.sender?.cancel(challenge)

            // Inform the user that the user name and password are incorrect
            completionHandler(.cancelAuthenticationChallenge, nil)
            return
        }
        print("Use Credential ....\n")

        completionHandler(.useCredential, self.getURLCredential())
    }

    func urlSession(_ session: URLSession, task: URLSessionTask, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        if challenge.previousFailureCount > 0
        {
            print("Alert Please check the credential")
            debugPrint("Alert Please check the credential")
            completionHandler(.cancelAuthenticationChallenge, nil)
        }

        challenge.sender?.use(self.getURLCredential(), for: challenge)
        completionHandler(.useCredential, self.getURLCredential())
    }

認証できません。

swift 3 でプロキシを認証する方法を教えてください。