swift – Learn how to run code within the background on iOS? Undecided which methodology is sensible

I am attempting to arrange background HTTP add requests (syncing information from the consumer’s telephone to a server) that set off periodically in my Swift app. I haven’t got strict necessities on when this runs (it could occur in a single day or all through the day).

I do know Apple gives a number of APIs for background duties on iOS (beginBackgroundTask, BGAppRefreshTaskRequest, BGProcessingTaskRequest, URLSession add vs. background session). And I’ve seen this publish on the Apple developer boards that makes an attempt to elucidate the variations and when to make use of which – in addition to Apple’s web page on the topic, nevertheless it’s nonetheless not clear to me how a couple of of those work in apply, and thus which of them I ought to make the most of for my use case.

My questions:

1. How ought to I schedule periodic file add duties within the background?
   • I assume I ought to use BGProcessingTaskRequest, since I do not know precisely how lengthy the duty will take (it could possibly be syncing simply 1-2 information, or it could possibly be a whole lot) and I do not care if it runs in a single day
2. How ought to I guarantee foreground duties are capable of full after closing the app? (i.e. when a consumer begins a sync manually within the app)
   • From Apple’s web page on URLSessionUploadTask: “In contrast to knowledge duties, you should use add duties to add content material within the background.”
     • Does this imply any requests I make utilizing URLSession.shared.add() will mechanically run within the background if the consumer closes the app? Even with the async/await model, or do I’ve to make use of the completionHandler model?
   • Do I must name beginBackgroundTask if I am utilizing URLSession.shared.add() to ensure I get extra time to complete uploads?
   • What about sequential requests (i.e. requests that have not began but by the point the app is closed)? Primarily based on this SO response, it feels like I could must set off all of the uploads in parallel beforehand? https://stackoverflow.com/a/53949607/2359478
3. Ought to I even contemplate URLSessionConfiguration.background for my use case? It sounds prefer it I exploit beginBackgroundTask and BGProcessingTaskRequest then this can be pointless?

Thanks!