快速测量上传速度答案

【问题标题】：Measure upload speed in swift快速测量上传速度
【发布时间】：2020-04-08 18:14:25
【问题描述】：

我有自己的服务器，我想用 Swift 将文件上传到其中。我还想测量上传速度。下面我创建一个空的 1 mb 数据对象并上传它。

        let urlString = "https://myserver/upload.php"
        guard let url = URL(string: urlString) else {
            return
        }

        var urlRequest = URLRequest(url: url, cachePolicy: .reloadIgnoringLocalAndRemoteCacheData, timeoutInterval: 10)
        urlRequest.httpMethod = "POST"
        urlRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")

        let emptyData = createEmptyData(of: 1048576)

        let json = ["file" : emptyData]
        urlRequest.httpBody = try? JSONEncoder().encode(json)

        let sessionConfiguration = URLSessionConfiguration.ephemeral
        let session = URLSession(configuration: sessionConfiguration, delegate: self, delegateQueue: nil)

        session.dataTask(with: urlRequest).resume()

如何测量上传速度？谢谢

【问题讨论】：

速度由距离或大小/时间决定。所以看看上传1Mb需要多长时间
@Scriptable 我应该在 URLSessionDelegate 的哪个委托方法中计算上传速度？
您不需要委托方法。 session.dataTask 有一个完成处理程序。你可以使用它。
@Scriptable 我明白了，谢谢

标签： ios swift upload

【解决方案1】：

      let urlString = "https://myserver/upload.php"
      guard let url = URL(string: urlString) else {
         return
      }

     var timer: Timer?
     var uploadTask: URLSessionUploadTask!

     var urlRequest = URLRequest(url: url, cachePolicy: .reloadIgnoringLocalAndRemoteCacheData, timeoutInterval: 10)
     urlRequest.httpMethod = "POST"
     urlRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")

     let emptyData = Data.init(capacity: 102454)

     let json = ["file" : emptyData]
     urlRequest.httpBody = try? JSONEncoder().encode(json)

     let sessionConfiguration = URLSessionConfiguration.ephemeral
     let session = URLSession(configuration: sessionConfiguration, delegate: self, delegateQueue: nil)
     uploadTask = session.uploadTask(with: urlRequest, from: emptyData) { (data, response, error) in
        if let err = error {
            //There's an error
        }
        else if let response = response {
            //check for response status
        }

        //Stop the timer here
        timer?.invalidate()
      }

    uploadTask.resume()
    calculateSpeed()
}


func calculateSpeed() {
    var previousBytesSent: Int64 = 0
    timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true, block: { (_) in
        let bytesSent = uploadTask.countOfBytesSent
        let speed =  abs(bytesSent-previousBytesSent)
        //Here you get the speed in Bytes/sec
        previousBytesSent = bytesSent
    })
}

【讨论】：

这里，您使用的是uploadTask 而不是dataTask。因此，您在 JSON 正文和任务本身中都提供了空数据。对吗？
你也可以使用dataTask。像 countOfBytesSent、countOfBytesReceived 等属性在 DataTask 中也可用，因为它们都继承自 URLSessionTask。

【解决方案2】：

为什么不在方法的开头使用 Core Foundation 的绝对时间方法，并在上传完文件后从方法结尾的绝对时间中减去该值。

func uploadData(){
        let start = CFAbsoluteTimeGetCurrent()
        var uploadTask: URLSessionUploadTask!

//Code for uploading file

        uploadTask = session.uploadTask(with: urlRequest, from: emptyData) { (data, response, error) in
        if let err = error {
            //There's an error
        }
        else if let response = response {
            //check for response status
        }

       //Once upload is complete
       let totalUploadTime = CFAbsoluteTimeGetCurrent() - start
      }





}

【讨论】：