Downloader

public class Downloader : NSObject
extension Downloader: URLSessionDownloadDelegate

Downloader: A helper class to download files.

  • Downloads a file asynchronously.

    Usage Example:

    • Download MNIST files:
      let semaphore = DispatchSemaphore(value: 0)
  let downloader = Downloader()
  var localURL: URL?
  downloader.download(
      fileAt: URL(string: "https://storage.googleapis.com/cvdf-datasets/mnist/train-images-idx3-ubyte.gz")!,
      cacheName: "mnist",
      fileName: "train-images.gz"
  ) { url, error in
      guard let url = url else {
          if let error = error { print(error) }
          fatalError("Data not downloaded.")
      }
      localURL = url
      semaphore.signal()
  }
  semaphore.wait()
  // Use the URL here.

    Declaration

    Swift

    public func download(fileAt remoteUrl: URL,
                     cacheName: String,
                     fileName: String,
                     completionHandler: @escaping (URL?, Error?) -> Void)

  • Downloads a file synchronously.

    Usage Example:

    • Download MNIST files:
      let localURL = Downloader.download(
      fileAt: URL(string: "https://storage.googleapis.com/cvdf-datasets/mnist/train-images-idx3-ubyte.gz")!,
      cacheName: "mnist",
      fileName: "train-images.gz"
  )
  // Use the URL here.

    Declaration

    Swift

    static public func download(fileAt remoteUrl: URL,
                            cacheName: String,
                            fileName: String) -> URL?

  • Undocumented

    Declaration

    Swift

    public func urlSession(_ session: URLSession,
                       downloadTask: URLSessionDownloadTask,
                       didWriteData bytesWritten: Int64,
                       totalBytesWritten: Int64,
                       totalBytesExpectedToWrite: Int64)

  • Undocumented

    Declaration

    Swift

    public func urlSession(_ session: URLSession,
                       downloadTask: URLSessionDownloadTask,
                       didFinishDownloadingTo location: URL)

  • Undocumented

    Declaration

    Swift

    public func urlSession(_ session: URLSession,
                       task: URLSessionTask,
                       didCompleteWithError error: Error?)