Definitive approach for retrieving transaction id

Hello!

I’m trying to find the definitive approach for retrieving a (non-consumable) purchase transaction id (that remains static for the lifetime of the purchase) using Unity IAP.

I need this for both Google & Apple at point of sale (in the same session) and in a different session (either online or offline)

From what I can tell, the following is available…

  1. Product.transactionID >> The documentation implies current session only

  2. Product.appleOriginalTransactionID >> The documentation implies current session only

  3. Product.receipt >> But I am trying to avoid platform specific receipt parsing as it makes future maintenance harder (should the platform receipt format change)

  4. GooglePlayReceipt.transactionID >> But there are no API calls to create\retrieve such an object from what I can see

  5. AppleInAppPurchaseReceipt.originalTransactionIdentifier >> But there are no API calls to create\retrieve such an object from what I can see

Is anyone from Unity able to offer any advice here please?

Short of spending many days putting together some test code & products etc, it’s difficult to know how to achieve this with the documentation available.

Any help would be much appreciated.