Restoring Purchases

Let users restore their previous non-consumable and subscription purchases on a new device or after reinstalling.

Provide a Restore Purchases button (for example in your settings screen) so users who reinstalled your app or switched devices can regain access to their non-consumable and subscription purchases without paying again.

Trigger a restore

@MainActor func restoreCompletedTransactions(
    completion: ((Result<Void, OnsidePaymentQueueRequestRestoreError>) -> Void)?
)

func restoreTapped() {
    Onside.defaultPaymentQueue().restoreCompletedTransactions { result in
        if case .failure(let error) = result {
            print("Couldn't start restore: \(error)")   // .loginDiscarded
        }
    }
}

The completion argument is required — pass a closure or completion: nil. Like add(_:completion:), the completion only reports the pre-flight outcome (OnsidePaymentQueueRequestRestoreError.loginDiscarded if the user dismisses the login screen). Restored transactions are delivered through your observer.

Receive restored transactions

Restored purchases are delivered to the same onsidePaymentQueue(_:updatedTransactions:) observer method, with a state of .restored. Handle them exactly like a purchase — unlock content and finish the transaction:

case .restored:
    unlockContent(for: transaction.payment.product.productIdentifier)
    queue.finishTransaction(transaction)

(See Making a Purchase for the full switch.)

Know when the restore finishes

After all restored transactions are delivered, OnsideKit calls one of two optional observer methods. Use them to update your UI (e.g. hide a spinner):

func onsidePaymentQueueRestoreCompletedTransactionsFinished(_ queue: OnsidePaymentQueue) {
    // Restore finished successfully.
}

func onsidePaymentQueue(
    _ queue: OnsidePaymentQueue,
    restoreCompletedTransactionsFailedWithError error: OnsideTransactionsRestoreError
) {
    // Restore failed — show an error.
}

Restore errors

OnsideTransactionsRestoreError:

Case	Cause
.cancelled	The restore was cancelled.
.connectionError	Network failure.
.serviceUnavailable	Server returned 5xx.
.appNotRegistered	The app/install isn't recognized by Onside (HTTP 404).
.internalError	Parsing or other unexpected error.

See the full Error Reference.