DownloadResponse

public struct DownloadResponse<Success, Failure> where Failure : Error
extension DownloadResponse: CustomStringConvertible, CustomDebugStringConvertible

Used to store all data associated with a serialized response of a download request.

  • The URL request sent to the server.

    Declaration

    Swift

    public let request: URLRequest?

  • The server’s response to the URL request.

    Declaration

    Swift

    public let response: HTTPURLResponse?

  • The final destination URL of the data returned from the server after it is moved.

    Declaration

    Swift

    public let fileURL: URL?

  • The resume data generated if the request was cancelled.

    Declaration

    Swift

    public let resumeData: Data?

  • The final metrics of the response.

    Note

    Due to FB7624529, collection of URLSessionTaskMetrics on watchOS is currently disabled.`

    Declaration

    Swift

    public let metrics: URLSessionTaskMetrics?

  • The time taken to serialize the response.

    Declaration

    Swift

    public let serializationDuration: TimeInterval

  • The result of response serialization.

    Declaration

    Swift

    public let result: Result<Success, Failure>

  • Returns the associated value of the result if it is a success, nil otherwise.

    Declaration

    Swift

    public var value: Success? { get }

  • Returns the associated error value if the result if it is a failure, nil otherwise.

    Declaration

    Swift

    public var error: Failure? { get }

  • Creates a DownloadResponse instance with the specified parameters derived from response serialization.

    Declaration

    Swift

    public init(request: URLRequest?,
            response: HTTPURLResponse?,
            fileURL: URL?,
            resumeData: Data?,
            metrics: URLSessionTaskMetrics?,
            serializationDuration: TimeInterval,
            result: Result<Success, Failure>)

    Parameters

    request

    The URLRequest sent to the server.
    response

    The HTTPURLResponse from the server.
    fileURL

    The final destination URL of the data returned from the server after it is moved.
    resumeData

    The resume Data generated if the request was cancelled.
    metrics

    The URLSessionTaskMetrics of the DownloadRequest.
    serializationDuration

    The duration taken by serialization.
    result

    The Result of response serialization.

  • The textual representation used when written to an output stream, which includes whether the result was a success or failure.

    Declaration

    Swift

    public var description: String { get }

  • The debug textual representation used when written to an output stream, which includes the URL request, the URL response, the temporary and destination URLs, the resume data, the durations of the network and serialization actions, and the response serialization result.

    Declaration

    Swift

    public var debugDescription: String { get }

  • Evaluates the given closure when the result of this DownloadResponse is a success, passing the unwrapped result value as a parameter.

    Use the map method with a closure that does not throw. For example:

    let possibleData: DownloadResponse<Data> = ...
let possibleInt = possibleData.map { $0.count }

    Declaration

    Swift

    public func map<NewSuccess>(_ transform: (Success) -> NewSuccess) -> DownloadResponse<NewSuccess, Failure>

    Parameters

    transform

    A closure that takes the success value of the instance’s result.

    Return Value

    A DownloadResponse whose result wraps the value returned by the given closure. If this instance’s result is a failure, returns a response wrapping the same failure.

  • Evaluates the given closure when the result of this DownloadResponse is a success, passing the unwrapped result value as a parameter.

    Use the tryMap method with a closure that may throw an error. For example:

    let possibleData: DownloadResponse<Data> = ...
let possibleObject = possibleData.tryMap {
    try JSONSerialization.jsonObject(with: $0)
}

    Declaration

    Swift

    public func tryMap<NewSuccess>(_ transform: (Success) throws -> NewSuccess) -> DownloadResponse<NewSuccess, Error>

    Parameters

    transform

    A closure that takes the success value of the instance’s result.

    Return Value

    A success or failure DownloadResponse depending on the result of the given closure. If this instance’s result is a failure, returns the same failure.

  • Evaluates the specified closure when the DownloadResponse is a failure, passing the unwrapped error as a parameter.

    Use the mapError function with a closure that does not throw. For example:

    let possibleData: DownloadResponse<Data> = ...
let withMyError = possibleData.mapError { MyError.error($0) }

    Declaration

    Swift

    public func mapError<NewFailure>(_ transform: (Failure) -> NewFailure) -> DownloadResponse<Success, NewFailure> where NewFailure : Error

    Parameters

    transform

    A closure that takes the error of the instance.

    Return Value

    A DownloadResponse instance containing the result of the transform.

  • Evaluates the specified closure when the DownloadResponse is a failure, passing the unwrapped error as a parameter.

    Use the tryMapError function with a closure that may throw an error. For example:

    let possibleData: DownloadResponse<Data> = ...
let possibleObject = possibleData.tryMapError {
    try someFailableFunction(taking: $0)
}

    Declaration

    Swift

    public func tryMapError<NewFailure>(_ transform: (Failure) throws -> NewFailure) -> DownloadResponse<Success, Error> where NewFailure : Error

    Parameters

    transform

    A throwing closure that takes the error of the instance.

    Return Value

    A DownloadResponse instance containing the result of the transform.