func storageDownloadCombinedExample()

in storage/StorageReferenceSwift/ViewController.swift [470:530]

• 36 lines of code
• 5 McCabe index (conditional complexity)

  func storageDownloadCombinedExample() {
    let storageRef = Storage.storage().reference()
    let localURL = URL(string: "path/to/image")!

    // [START firstorage_download_combined]
    // Create a reference to the file we want to download
    let starsRef = storageRef.child("images/stars.jpg")

    // Start the download (in this case writing to a file)
    let downloadTask = storageRef.write(toFile: localURL)

    // Observe changes in status
    downloadTask.observe(.resume) { snapshot in
      // Download resumed, also fires when the download starts
    }

    downloadTask.observe(.pause) { snapshot in
      // Download paused
    }

    downloadTask.observe(.progress) { snapshot in
      // Download reported progress
      let percentComplete = 100.0 * Double(snapshot.progress!.completedUnitCount)
        / Double(snapshot.progress!.totalUnitCount)
    }

    downloadTask.observe(.success) { snapshot in
      // Download completed successfully
    }

    // Errors only occur in the "Failure" case
    downloadTask.observe(.failure) { snapshot in
      guard let errorCode = (snapshot.error as? NSError)?.code else {
        return
      }
      guard let error = StorageErrorCode(rawValue: errorCode) else {
        return
      }
      switch (error) {
      case .objectNotFound:
        // File doesn't exist
        break
      case .unauthorized:
        // User doesn't have permission to access file
        break
      case .cancelled:
        // User cancelled the download
        break

      /* ... */

      case .unknown:
        // Unknown error occurred, inspect the server response
        break
      default:
        // Another error occurred. This is a good place to retry the download.
        break
      }
    }
    // [END firstorage_download_combined]
  }