title: Add progress to file uploading using Alamofire
body: <p>How can I get progress of file uploading?</p>
  
  <pre><code>// import Alamofire
    func uploadWithAlamofire() {
      let image = UIImage(named: "myImage")!
  
      // define parameters
      let parameters = [
        "hometown": "yalikavak",
        "living": "istanbul"
      ]
  
      // Begin upload
      Alamofire.upload(.POST, "upload_url",
        // define your headers here
        headers: ["Authorization": "auth_token"],
        multipartFormData: { multipartFormData in
  
          // import image to request
          if let imageData = UIImageJPEGRepresentation(image, 1) {
            multipartFormData.appendBodyPart(data: imageData, name: "file", fileName: "myImage.png", mimeType: "image/png")
          }
  
          // import parameters
          for (key, value) in parameters {
            multipartFormData.appendBodyPart(data: value.dataUsingEncoding(NSUTF8StringEncoding)!, name: key)
          }
        }, // you can customise Threshold if you wish. This is the alamofire's default value
        encodingMemoryThreshold: Manager.MultipartFormDataEncodingMemoryThreshold,
        encodingCompletion: { encodingResult in
          switch encodingResult {
          case .Success(let upload, _, _):
            upload.responseJSON { response in
              debugPrint(response)
            }
          case .Failure(let encodingError):
            print(encodingError)
          }
      })
    }
  </code></pre>
  
  <p>I know something like I have to add progress block but don't know where can I add that progress block.</p>
  
  <pre><code>.progress { (bytesWritten, totalBytesWritten, totalBytesExpectedToWrite) in
          println("\(totalBytesWritten) / \(totalBytesExpectedToWrite)")
      }
  </code></pre>
  
  <p>I want to add above block and how can I calculate estimated time for video uploading.</p>