deleteStoredDeviceData does not wait for files to be deleted

[korzonkiee]

Platform on which you observed the bug:

• Android
• iOS
• Other
• Platform is not relevant for this bug

Device on which you observed the bug:

• Polar OH1
• Polar Verity Sense
• Polar H10
• Polar H9
• Other
• Device is not relevant for this bug

Describe the bug
Looking at the implementation of deleteDataDirectories on Android it looks like the method does not wait for all the underlying operations to complete. Also, in case of any errors they won't be reported, because the metod always returns complete.

Expected behavior
deleteDataDirectories method should complete after all files have been deleted, all errors should be reported to the caller that subscribes to it.

[korzonkiee]

The same thing happens on iOS.

https://github.com/polarofficial/polar-ble-sdk/blob/master/sources/iOS/ios-communications/Sources/PolarBleSdk/sdk/impl/PolarBleApiImpl.swift#L2773

[korzonkiee]

We managed to tweak the deleteListedFilesByType for AUTO_SAMPLE data type in our own fork. It now waits for deleting process to complete. Additionally it has been improved to respect the until date and log more for better visibility. Feel free to check it out, it may be helpful for someone responsible for implementing it into official repo.

korzonkiee@7bfb151

[korzonkiee]

Implemented the same thing for Android.

korzonkiee@6dc58cf

[palmqvisti]

Thank you for helping to solve this. The fix will be released in the next release.

[samulimaa]

This should be fixed in the latest SDK release 5.10.0.

[korzonkiee]

Thank you, @samulimaa. I appreciate you taking the time to investigate this.

If I understand correctly, the current implementation blocks the thread until deleteOpCompleted becomes true (see here). This flag is only set to true once all requested files have been deleted.

While this approach may work in the ideal case, I have concerns about its behavior when errors occur. For example, if a file deletion fails due to a connection interruption, deleteOpCompleted would never be set to true, causing the while loop to run indefinitely.

Given that the SDK relies heavily on the reactive paradigm through RxSwift and RxKotlin, I believe it would be beneficial to offer a solution that aligns with this pattern. While it may require more effort, such a solution would maintain consistency with the architecture and handle error cases more effectively. I am happy to assist with this, as I have already worked on similar improvements.

cc @palmqvisti