PostProcessing

public protocol PostProcessing

The PostProcessing protocol is used to create post-processes that can be used after the file has been downloaded. For example, unzip .zip files or create image thumbnails.

The implementation requirements for post-processing are as follows. For the correct operation, the object that is inherited from PostProcessing must be Value Types (struct). Under the supportedFileExtensions parameter, specify a list of file extensions over which post-processing can be performed. Use the prepare method to get the data you need to start post-processing. Describe the logic behind post-processing in the process method. Call onComplete, after the completion of post-processing.

  • A set of file extensions over which post-processing will be performed.

    Example: supportedFileExtensions = [png, jpg]

    Declaration

    Swift

    var supportedFileExtensions: Set<String> { get }

  • Used to report about the completion of post-processing.

    If the post-processing failed, then an Error object must be passed.

    Declaration

    Swift

    var onComplete: ((_ withError: Error?) -> Void)? { get set }

  • This method passes parameters that may be needed to start post-processing.

    Since all parameters are Value Types, you can store the needed parameters globally.

    Declaration

    Swift

    mutating mutating func prepare(fileStorage: FileStorage?, filename: String?, fileExtention: String?, sourceLocation: URL?)

    Parameters

    fileStorage

    Use this parameter if you need to save or delete a file.
    filename

    Local filename.
    fileExtention

    File extention.
    sourceLocation

    The reference to the source file on which post-processing should be performed.

  • The post-processing logic should be described in this method.

    The process method is used in PostProcessingOperation to start processing.

    Declaration

    Swift

    func process()

  • Will be called when operation is canceled.

    Declaration

    Swift

    func cancel() -> Error?
  • name Extension method

    A post process name, used for identification.

    Optional value. The default value is equal to the class name.

    Declaration

    Swift

    var name: String { get }