ImageDownloadRequestModifier
public protocol ImageDownloadRequestModifier
Represents and wraps a method for modifying request before an image download request starts.
-
A method will be called just before the
request
being sent. This is the last chance you can modify the image download request. You can modify the request for some customizing purpose, such as adding auth token to the header, do basic HTTP auth or something like url mapping.Usually, you pass an
ImageDownloadRequestModifier
as the associated value ofKingfisherOptionsInfoItem.requestModifier
and use it as theoptions
parameter in related methods.If you do nothing with the input
request
and return it as is, a downloading process will start with it.Declaration
Swift
func modified(for request: URLRequest) -> URLRequest?
Parameters
request
The input request contains necessary information like
url
. This request is generated according to your resource url as a GET request.Return Value
A modified version of request, which you wish to use for downloading an image. If
nil
returned, aKingfisherError.requestError
with.emptyRequest
as its reason will occur.