ios - Swift 4 - 使用 URLSession 获取上传图片进度

Question

我下面有这种代码

func upload(){
    let img = UIImage(named: "1")
    let imgData = UIImageJPEGRepresentation(img!, 1)
    let data = imgData?.base64EncodedString()

    var request = URLRequest(url: URL(string: url)!)
    request.httpMethod = "POST"
    request.setValue("\(auth)", forHTTPHeaderField: "Authorization")
    request.setValue("application/xml", forHTTPHeaderField: "Content-Type")

    var postString = "<uploadrequest>"
    postString += "<folderid>123</folderid>"
    postString += "<folder_name>images</folder_name>"
    postString += "<image_byte>\(data!)</image_byte>"
    postString += "</uploadrequest>"

    request.httpBody = postString.data(using: .utf8)

    let configuration = URLSessionConfiguration.default
    let session = URLSession(configuration: configuration, delegate: self, delegateQueue: OperationQueue.main)

    let task = session.uploadTask(with: request, from: imgData!, completionHandler: {
        (data, response, error) -> Void in

        if let error = error {
            print(error)
            return
        }
        if let data = data {
            _ = self.parseJsonData(data: data)
        }
    })

    task.resume()
}

func urlSession(_ session: URLSession, task: URLSessionTask, didSendBodyData bytesSent: Int64, totalBytesSent: Int64, totalBytesExpectedToSend: Int64) {
    print("sent:", totalBytesSent, "from:", totalBytesExpectedToSend)

    let size = totalBytesSent / totalBytesExpectedToSend
    self.progressbar.progress = Float(size)
}

我的目标是使用 API 上传图片并获取其上传进度。图像被转换为​​ base64 并插入到 <image_byte>\(data!)</image_byte>。在 API 的 poststring 上。

然后我得到的是这样的:

sent: 32768 from: 927220 sent: 65536 from: 927220 sent: 131072 from: 927220 sent: 163840 from: 927220 sent: 262144 from: 927220 sent: 294912 from: 927220 sent: 360448 from: 927220 sent: 393216 from: 927220 sent: 425984 from: 927220 sent: 491520 from: 927220 sent: 524288 from: 927220 sent: 557056 from: 927220 sent: 589824 from: 927220 sent: 622592 from: 927220 sent: 655360 from: 927220 sent: 688128 from: 927220 sent: 720896 from: 927220 sent: 786432 from: 927220 sent: 819200 from: 927220 sent: 851968 from: 927220 sent: 927220 from: 927220 Error Domain=NSCocoaErrorDomain Code=3840 "JSON text did not start with array or object and option to allow fragments not set." UserInfo={NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}

但是如果我使用其他类似的方法(没有 uploadTask)，效果很好但没有上传进度。

let task = URLSession.shared.dataTask(with: request, completionHandler: {
        (data, response, error) -> Void in

        if let error = error {
            print(error)
            return
        }
        if let data = data {
            _ = self.parseJsonData(data: data)
        }
    })

我试过了 Alamofire也。 Alamofire与 request功能成功但仍然没有上传进度和Alamofire与 upload函数 (multipartformData) 出现此错误:

responseSerializationFailed(reason: Alamofire.AFError.ResponseSerializationFailureReason.jsonSerializationFailed(error: Error Domain=NSCocoaErrorDomain Code=3840 "Invalid value around character 3." UserInfo={NSDebugDescription=Invalid value around character 3.}))

我想知道我的代码是否有误。你能告诉我应该如何处理我的代码吗？或者问题出在我的 API 上，因为我的 API 只接受 base64代码？

如果你想看我的Alamofire代码，它是 there

拜托，有人帮我解决这个问题。

谢谢! :)

编辑 1

这是我通过请求函数得到的结果(没有上传函数)

{
    "media_preview" =     {
        "image_media" =         {
            fileid = 4928501;
            filename = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            folderpath = "product\\66861/images800\\";
            height = 533;
            src = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            width = 800;
        };
        "medium_media" =         {
            fileid = 4928503;
            filename = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            folderpath = "product\\66861/images500\\";
            height = 333;
            src = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            width = 500;
        };
        "small_media" =         {
            fileid = 4928503;
            filename = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            folderpath = "\product\\66861/images300\\";
            height = 200;
            src = "/zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            width = 300;
        };
        "source_media" =         {
            fileid = 4928499;
            filename = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            folderpath = "\\product\\66861images\\";
            height = 666;
            src = "/zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            width = 999;
        };
        "thumbnail_media" =         {
            fileid = 4928507;
            filename = "zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            folderpath = \\product\\66861/thumb\\";
            height = 150;
            src = "/zhzvoHBb1ogda9bps13R5IavYiadCm.jpg";
            width = 150;
        };
    };
    responsestatus =     {
        "access_token" = "<null>";
        code = 00;
        description = Success;
    };
}

编辑 2这是 parseJsonData(data: Data) 的代码

func parseJsonData(data: Data) {
    do {
        let jsonResult = try JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary
        print(jsonResult!)
    } catch {
        print(error)
    }
}

Answer 1

要获取进度，请使用以下 URLSession 的委托(delegate)方法，您可以在 didReceiveData 方法中获取进度

func URLSession(session: NSURLSession, dataTask: NSURLSessionDataTask, didReceiveResponse response: NSURLResponse, completionHandler: (NSURLSessionResponseDisposition) -> Void) {

        //here you can get full lenth of your content
        expectedContentLength = Int(response.expectedContentLength)
        println(expectedContentLength)
        completionHandler(NSURLSessionResponseDisposition.Allow)
    }

    func URLSession(session: NSURLSession, dataTask: NSURLSessionDataTask, didReceiveData data: NSData) {


        buffer.appendData(data)

        let percentageDownloaded = Float(buffer.length) / Float(expectedContentLength)
        progress.progress =  percentageDownloaded
    }

    func URLSession(session: NSURLSession, task: NSURLSessionTask, didCompleteWithError error: NSError?) {
        //use buffer here.Download is done
        progress.progress = 1.0   // download 100% complete
    }