Verification for non-subscription product

Please help me with understanding verifying purchased product.

I need to use it with Google Play Store, but it would be great if you add something about another platforms, also. if it's different.

Product does not consumes in game, it should be purchased once. And it's not a subscription because it should not be paid more than once.

I need to verify that product was purchased. I've found something about verifying in custom server, but I need to verify it without my server. I don't want to save data about is it purchased just in device.

How I tried to do it:
IStoreListener.ProcessPurchase with return PurchaseProcessingResult.Pending. Check it by IStoreController.products.WithID("product_id").hasReceipt. But it always returns false.

I also tried PurchaseProcessingResult.Complete but with same result.

What I'm doing wrong?

 

@ViacheslavRud Yes, you will want to save data about the purchase in the device, we don't currently offer inventory management. You could consider using PlayerPrefs to store purchase history, that is what many developers use. Or as you mentioned you could save purchases to the cloud, but is a bit more work.

 

Thanks. I found something about it in FAQ, but it's not clear
My game should propose disable ads for payment, and I don't want to lose data about this payment when user reinstall game or switch to another device.

There are no Non-Consumable product type now. Google Play Store provide 2 types: Managed and Subscription. I use Managed(because I want one-time payment) in Play Store and Non-Consumable type in Unity (But it does not matter, I guess, I used both variants). And after restart app controller.products.WithID("my_id").hasReceipt returns false.
I will provide logs a bit later.

 

Non-consumables will fire a ProcessPurchase upon reinstall. If the user switches to another device and is something you want to handle, this would be a good opportunity to save purchases to the cloud. Inventory management is under discussion as a feature for a future release, however there are no definite plans at this time.

 

Yes, I have just checked logs and I found that managed product fires ProcessPurchase after initializing IStoreListener.
But I set up my product as Consumable for testing purposes, it also works.
And it works even after reinstall. Maybe it because I return PurchaseProcessingResult.Pending? Is it right way?