iPhone inApp Purchase Queue won't clear out - iphone

Question

I have InApp purchasing setup in my app. I am having some weird behavior though. Each time I start up the app I call
[[SKPaymentQueue defaultQueue] addTransactionObserver:self];
to setup the initial observer. However this immediately triggers
- (void)paymentQueue:(SKPaymentQueue *)queue updatedTransactions:(NSArray *)transactions
with a full array of every transaction. I have tried just calling
[[SKPaymentQueue defaultQueue] finishTransaction: transaction];
on each of these transaction then restarting the app again but paymentQueue is still trigger as soon as I call addTransactionObserver. My main goal right now is just to flush the transaction queue and start clean. I don't know how I got into this state, nor how to get out of it.

Answer 1

Make sure you have implemented this method:
-(void)paymentQueue:(SKPaymentQueue *)queue removedTransactions:(NSArray *)transactions;

Answer 2

From SKPaymentTransactionObserver:PaymentQueue.. call:
SKPaymentQueue.default().finishTransaction(transaction)
Note that you can not call for all types. Calling finishTransaction for .purchasing will crash with error. So a for through all transactions is not a complete solution.
When you Call finishTransaction for .purchasing:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Cannot finish a purchasing transaction'

Answer 3

Put this somewhere to flush the queue (possibly your load method, but remove it in your final app):
for (SKPaymentTransaction* transaction in [[SKPaymentQueue defaultQueue] transactions]) {
[[SKPaymentQueue defaultQueue] finishTransaction:transaction];
}
When finishTransaction is called, the observer's removeTransaction method will be called when each one is moved.
I had 30 in my queue and I ended up getting 30 calls to that method.

Answer 4

I think your issue has to do with the Sandbox User accounts in iTunes Connect. If you don't have any sandbox users, this guide was really helpful getting them setup:
https://support.magplus.com/hc/en-us/articles/203809008-iOS-How-to-Test-In-App-Purchases-in-Your-App
If you have Sandbox Users:
You can try calling finishTransaction: however, you need to make sure the SKPaymentTransactionState of the transaction is acceptable.
Per the documentation on finishTransaction :
// Asynchronous.
// Remove a finished (i.e. failed or completed) transaction from the queue.
// Attempting to finish a purchasing transaction will throw an exception.
So to safely remove completed transactions:
for transaction in SKPaymentQueue.default().transactions {
guard
transaction.transactionState != .purchasing,
transaction.transactionState != .deferred
else {
//Optionally provide user feedback for pending or processing transactions
return
}
//Transaction can now be safely finished
SKPaymentQueue.default().finishTransaction(transaction)
}
The documentation on .purchasing and .deferred is fairly vague:
case purchasing // Transaction is being added to the server queue.
case deferred // The transaction is in the queue, but its final status is pending external action.
From what I understand, handling pending and/or processing transactions should be fairly passive. The app has done everything it has needed to and is waiting on a response from the iTunes Store server, or some other dependency(i.e. payment authorization).
paymentQueue: updatedTransactions: will get called on the queue's SKPaymentTransactionObserver when the transaction is updated.
As far as how your transaction queue got stuck in limbo, I'm willing to bet all the transactions in your queue are in state .purchasing. This is most likely a bug within iTunes Connect/Sandbox users/Production iTunes Accounts. Others, including myself, have had this issue as well. There is a bug report filed for it. Try recreating/changing the password of your sandbox user, or create a new Sandbox User for testing.
More info here:
https://forums.developer.apple.com/thread/70418

Answer 5

You have to be sure you finish the transaction every time you make a purchase or you restore a product. If you run into this problem, you should clean up your queue and then develop the logic appropriately. A quick clean up could be obtained by running something like this in swift 3. (which is the same as the previous answer). But it is not supposed to be in your real app.
func cleanUp() {
for transaction in SKPaymentQueue.default().transactions {
SKPaymentQueue.default().finishTransaction(transaction)
}
}
Also you have to add and remove your observer in appDelegate. That is the recommendation and the best to avoid problems.