NSURLSessionDownloadTask cannot be resumed after network connection loss

Originator:lipovacjetu
Number:rdar://28513908 Date Originated:28.9.2016
Status:Open Resolved:-
Product:iOS SDK Product Version:
Classification: Reproducible:Always
 
Summary:
If you experience a loss of internet connection during the download (NSURLSession, iOS10, background download), when you connect again -URLSession:didBecomeInvalidWithError is called with "unsupported URL" error, without any resume data to continue the download. Therefore, all download progress is lost.

Steps to Reproduce:
1. Start download with NSURLSession
2. Force internet connection loss (turn onairplane mode for instance)
3. Connect to the internet again
4. Error will be produced in -URLSession:didBecomeInvalidWithError

Expected Results:
Download should be able to continue.

Actual Results:
Download progress is lost.

Version:
iOS 10.0 (14A345), iOS 10.0.1 (14A403)

Configuration:
Any iOS device, iOS10+, WiFi / mobile network

Comments


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