1

I am running into a really weird problem where I can't quite nail down the root cause. Our app used to function properly for background/silent notifications for ios12 and ios13 up until a few weeks ago. So a bit of background information:

  1. We use SNS to send visual/audible and silent background notifications.
  2. We are aware of the apns-push-type header that is required for ios13. SNS automatically handles this new header and our manual testing (i.e. without SNS) have also produced the same results.
  3. The silent notifications (i.e. content-available: 1) always fail on ios13.3 (or higher) but always work on ios12.4 (and below).
  4. In our swift code, we are using :didReceiveRemoteNotification:fetchCompletionHandler for silent notifications. We are also using userNotificationCenter (with willPresent and didReceive). Whenever we send audible/visual notifications, willPresent gets triggered on ios12 and ios13. On ios12, silent notifications trigger didReceiveRemoteNotification:fetchCompletionHandler but nothing with ios13.
  5. During our testing, we successfully sent an empty alert type to trigger a silent notification on ios13 and this works on ios12 as well (this triggers willPresent). This feels like a hack to me because it will likely wakeup the device momentarily and the notification will disappear if the app is running in the background.
  6. In other viewcontrollers, we are observing NotificationCenter for received messages to take appropriate actions.

To me it seems, {"content-available": 1} never works on ios13 and but does on ios12. Also didReceiveRemoteNotification:fetchCompletionHandler never gets called on ios13 but does on ios12. Our intent with silent notifications with (i.e. with content-available:1) is to refresh the details from our service when changes occur when the app is in foreground or background.

Any help would be appreciated.

whawhat
  • 175
  • 2
  • 7
  • https://stackoverflow.com/a/58525437/341994 – matt Apr 20 '20 at 21:11
  • @matt: Thank you for sharing the link but I don't think it is relevant here mainly because silent notifications are not arriving or handled correctly (simple print statements don't show anything at all) on ios13 but they are working with the same code on ios12. – whawhat Apr 20 '20 at 21:24
  • Well the link tells you how to watch the notification arrive at system level. – matt Apr 20 '20 at 21:51

1 Answers1

0

I was able to resolve this issue. Before I get into the solution, however, I want to mention that I ran into this problem only on iOS13 and with silent notifications. The same code was working with iOS12 with same feature.

Our app has a separate screen for requesting notification permissions when the app is launched first time. At this stage we register the device for notifications. Next time when the app is launched, we don't show this screen anymore. To get it to work on ios13, we had to re-register with APNS in AppDelegate's didFinishLaunchingWithOptions every single time. Again, on iOS12 silent notifications were working without re-registering with APNS but on iOS13 we have to re-register every single time.

I hope this helps anyone else running into this problem.

whawhat
  • 175
  • 2
  • 7