# inAppPurchase  _macOS_

> In-app purchases on Mac App Store.

Process: [Main](../glossary.md#main-process)

## Events

The `inAppPurchase` module emits the following events:

### Event: 'transaction-updated'

Emitted when a transaction has been updated.

Returns:

* `event` Event
* `transaction` Object
  * `transactionIdentifier` String
  * `transactionDate` String
  * `originalTransactionIdentifier` String
  * `transactionState` String - The transaction sate (`"purchasing"`, `"purchased"`, `"failed"`, `"restored"`, or `"deferred"`)
  * `errorCode` Integer
  * `errorMessage` String
  * `payment` Object
    * `productIdentifier` String
    * `quantity` Integer

## Methods

The `inAppPurchase` module has the following methods:

### `inAppPurchase.purchaseProduct(productID, quantity, callback)`

* `productID` String - The id of the product to purchase. (the id of `com.example.app.product1` is `product1`).
* `quantity` Integer (optional) - The number of items the user wants to purchase.
* `callback` Function (optional) - The callback called when the payment is added to the PaymentQueue. (You should add a listener with `inAppPurchase.addTransactionsListener` to get the transaction status).
  * `isProductValid` Boolean - Determine if the product is valid and added to the payment queue.

### `inAppPurchase.canMakePayments()`

Returns `true` if the user can make a payment and `false` otherwise.

### `inAppPurchase.getReceiptURL()`

Returns `String`, the path to the receipt.