通过aws ios sdk

Question

我希望用户在注册我的应用时上传到我的S3存储桶的个人资料图片。

我是否需要先从Facebook下载图片，还是可以将外部网址传递给AWSS3TransferManager？我当然希望不必先将图片下载到客户端的设备中，然后再上传到S3。

//We create the url to the FB Profile Picture
    NSString *compURLString = [NSString stringWithFormat:@"https://graph.facebook.com/FACEBOOKID/picture?type=large"];
    NSURL *url = [NSURL URLWithString:compURLString];
    // We download the FB Profile Picture from Facebook TBD DO WE NEED THIS STEP OR IS IT POSSIBLE TO PASS THE EXTERNAL URL? AND NOT DOWNLOAD THE IMAGE FIRST? https://graph.facebook.com/FACEBOOKID/picture?type=large TO THE AWS UPLOAD MANAGER
    NSURLSessionDownloadTask *downloadPhotoTask = [[NSURLSession sharedSession]
                                                   downloadTaskWithURL:url completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) {
                                                       UIImage 

                                   // NOw that we have the FB Profile Picture, we upload it to S3
        AWSS3TransferManager *uploadManager = [AWSS3TransferManager defaultS3TransferManager];

        NSString *const S3BucketName = @"DEMO";

       //upload the image
       AWSS3TransferManagerUploadRequest *uploadRequest = [AWSS3TransferManagerUploadRequest new];
       uploadRequest.body = location;
       uploadRequest.bucket = S3BucketName;
       uploadRequest.key = [NSString stringWithFormat:@"@%.jpg", facebookID];
       uploadRequest.contentType = @"image/jpg";

       [[uploadManager upload:uploadRequest] continueWithExecutor:[AWSExecutor mainThreadExecutor]
                                                     withBlock:^id(AWSTask *task) {...
                                                   }];

    [downloadPhotoTask resume];}