Uploading an Object Body

class delegate :NSObject, URLSessionDataDelegate{

  func uploadObjectBody(){
    // Check if a KiiUser is logged in.
    if KiiUser.current() == nil{
      return
    }

    // Create a KiiObject in a user-scope bucket.
    let bucket = KiiUser.current()!.bucket(withName: "MyBucket")
    let object = bucket.createObject()

    // Set key-value pairs.
    object.setObject("myVideo", forKey: "title")
    object.setObject(NSNumber(value: 10485760 as Int), forKey: "fileSize")

    // Save the KiiObject.
    object.save { (object : KiiObject?, error : Error?) -> Void in
      if error != nil {
        print("Object creation error!")
        return
      }

      // Prepare a URLSession object to upload the object body in the background.
      let contentType = "video/mp4"
      let uploadRequest = object!.generateUploadRequest(contentType)!
      let uuidStr = UUID().uuidString
      let randomSessionIdentifier = uuidStr.lowercased()
      let sessionConfig : URLSessionConfiguration
      sessionConfig = URLSessionConfiguration.background(withIdentifier: randomSessionIdentifier)
      sessionConfig.allowsCellularAccess = true
      let session = URLSession(configuration: sessionConfig, delegate: self, delegateQueue: OperationQueue.main)

      // Specify a file to upload.
      let targetDirectory : NSString = (NSHomeDirectory() as NSString).appendingPathComponent("Documents") as NSString
      let sourceFilePath = targetDirectory.appendingPathComponent("sample.mp4")
      let sourceFileURL = URL(fileURLWithPath: sourceFilePath)

      // Create an upload task.
      let uploadTask = session.uploadTask(with: uploadRequest, fromFile: sourceFileURL)

      // Start or resume the task.
      uploadTask.resume()
    }
  }

  @objc fileprivate func urlSession(_ session: URLSession, task: URLSessionTask, didSendBodyData bytesSent: Int64, totalBytesSent: Int64, totalBytesExpectedToSend: Int64) {
    // The upload is in progress.
    print("Progress : \(Float(totalBytesSent / totalBytesExpectedToSend))")
  }

  @objc fileprivate func urlSession(_ session : URLSession, task: URLSessionTask, didCompleteWithError error: Error? ){
    if error != nil {
      // Handle the error.
      print("Background transfer is failed")
      return
    }
    // Check the HTTP status code.
    let response = task.response as! HTTPURLResponse
    if response.statusCode >= 300 {
      print("Background transfer is failed, status code: \(response.statusCode)")
      return
    }
    print("Background transfer succeeded")
  }
}

- (void)uploadObjectBody {
  // Check if a KiiUser is logged in.
  if ([KiiUser currentUser] == nil) {
    return;
  }

  // Create a KiiObject in a user-scope bucket.
  KiiBucket *bucket = [[KiiUser currentUser] bucketWithName:@"MyBucket"];
  KiiObject *object = [bucket createObject];

  // Set key-value pairs.
  [object setObject:@"MyVideo"
             forKey:@"title"];
  [object setObject:[NSNumber numberWithInt:10485760]
             forKey:@"fileSize"];

  // Save the KiiObject.
  [object saveWithBlock:^(KiiObject *object, NSError *error) {
    if (error != nil) {
      // Handle the error.
      NSLog(@"Object creation error!");
      return;
    }

    // Prepare an NSURLSession object to upload the object body in the background.
    NSString *contentType = @"video/mp4";
    NSURLRequest *uploadRequest = [object generateUploadRequest:contentType];
    CFUUIDRef uuid = CFUUIDCreate(kCFAllocatorDefault);
    NSString *uuidStr = (__bridge_transfer NSString *) CFUUIDCreateString(kCFAllocatorDefault, uuid);
    CFRelease(uuid);
    NSString *randomSessionIdentifier = [uuidStr lowercaseString];
    NSURLSessionConfiguration *sessionConfig;
    sessionConfig = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:randomSessionIdentifier];
    sessionConfig.allowsCellularAccess = YES;
    NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfig
                                                          delegate:self
                                                     delegateQueue:[NSOperationQueue mainQueue]];

    // Specify a file to upload.
    NSString *targetDirectory = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];
    NSString *sourceFilePath = [targetDirectory stringByAppendingPathComponent:@"sample.mp4"];
    NSURL *sourceFileURL = [NSURL fileURLWithPath:sourceFilePath];

    // Create an upload task.
    NSURLSessionUploadTask *uploadTask = [session uploadTaskWithRequest:uploadRequest
                                                               fromFile:sourceFileURL];
    // Start or resume the task.
    [uploadTask resume];
  }];
}

- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didSendBodyData:(int64_t)bytesSent totalBytesSent:(int64_t)totalBytesSent totalBytesExpectedToSend:(int64_t)totalBytesExpectedToSend {
  // The upload is in progress.
  NSLog(@"Progress : %f", (float) totalBytesSent / totalBytesExpectedToSend);
}

- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {
  if (error != nil) {
    // Handle the error.
    NSLog(@"Background transfer is failed");
    return;
  }
  // Check the HTTP status code.
  NSHTTPURLResponse *response = (NSHTTPURLResponse *)task.response;
  if ([response statusCode] >= 300) {
    NSLog(@"Background transfer is failed, status code: %ld", (long)[response statusCode]);
    return;
  }
  NSLog(@"Background transfer succeeded");
}