In-app purchase verification

Inspired by the iap_verifier CoffeeScript module written by Paul Crawford, I wanted a pure JavaScript implementation of in-app purchase verification. I also wanted to add support for other app stores, and not just limit this to Apple. The iap module is exactly that. Pull requests to add support for other platforms are very welcome!

Installation

npm install iap

Usage

Initialisation

var iap = require('iap');

var platform = 'apple';
var payment = {
    receipt: 'receipt data', // always required
    productId: 'abc',
    packageName: 'my.app',
    secret: 'password',
    subscription: true, // optional, if google play subscription
    keyObject: {}, // required, if google
    userId: 'user id', // required, if amazon
    devToken: 'developer id' // required, if roku
};

Purchase verification ( all platforms )

A method is exposed to verify purchase receipts:

iap.verifyPayment(platform, payment, function (error, response) {
    /* your code */
});

Or, if you prefer a promise-based alternative:

iap.verifyPayment(platform, payment)
.then(
    response => {   
        /* your code */ 
    },
    error => {
        /* your code */ 
    }
)

The receipt you pass must conform to the requirements of the backend you are verifying with. Read the next chapter for more information on the format.

Subscription cancellation ( Google Play only )

Google exposes an API for server side cancellation of recurring suscriptions. This might be be used to enable users to easily cancel subscriptions from within the app ( without going to Play Store ), or to allow subscriptions to be canceled by support people when users request it ( when for some reason the users are unable or unwilling to do so themselves).

iap.cancelSubscription("google", payment, function (error, response) {
    /* your code */
});

Or, if you prefer a promise-based alternative:

iap.cancelSubscription(platform, payment)
.then(
    response => {    
        /* your code */ 
    },
    error => {
        /* your code */ 
    }
)

Supported platforms

Amazon

The payment object

The receipt string represents the transaction returned from a channel or product purchase.

A Shared secret and user ID is required.

The response

The response passed back to your callback will also be Amazon specific. The entire parsed receipt will be in the result object:

{
    "receipt": {
        "betaProduct": false,
        "cancelDate": null,
        "parentProductId": null,
        "productId": "com.amazon.iapsamplev2.gold_medal",
        "productType": "CONSUMABLE",
        "purchaseDate": 1399070221749,
        "quantity": 1,
        "receiptId": "wE1EG1gsEZI9q9UnI5YoZ2OxeoVKPdR5bvPMqyKQq5Y=:1:11",
        "renewalDate": null,
        "term": null,
        "termSku": null,
        "testTransaction": false
    },
    "transactionId": "wE1EG1gsEZI9q9UnI5YoZ2OxeoVKPdR5bvPMqyKQq5Y=:1:11",
    "productId": "com.amazon.iapsamplev2.gold_medal",
    "platform": "amazon"
}

Apple

The payment object

The receipt string passed may be either the base64 string that Apple really wants, or the decoded receipt as returned by the iOS SDK (in which case it will be automatically base64 serialized).

Both productId and packageName (bundle ID) are optional, but when provided will be tested against. If the receipt does not match the provided values, an error will be returned.

To verify auto-renewable subscriptions you need to provide secret field that contains your In-App Purchase Shared Secret

Apple supports returning only the most recent transaction for auto-renewable subscriptions via their exclude-old-transactions option. This can greatly save on bandwidth for users that have more than one transaction. To enable this, pass excludeOldTransactions on the payment object:

let payment = {
  ...
  excludeOldTransactions: true
}

The response

The response passed back to your callback will also be Apple specific. The entire parsed receipt will be in the result object. Applications that support monthly and yearly subscription access will represent auto-renewable terms in either the in_app or latestReceiptInfo property.

{
    "receipt": {
        "original_purchase_date_pst": "2016-10-29 15:46:57 America/Los_Angeles",
        "purchase_date_ms": "1477802802000",
        "unique_identifier": "78abf2209323434771637ee22f0ee8b8341f14b4",
        "original_transaction_id": "120000257973875",
        "bvrs": "0.0.1",
        "transaction_id": "120000265421254",
        "quantity": "1",
        "unique_vendor_identifier": "206FED24-2EAB-4FC6-B946-4AF61086DF21",
        "item_id": "820817285",
        "product_id": "abc",
        "purchase_date": "2016-10-29 22:46:57 Etc/GMT",
        "original_purchase_date": "2016-10-29 22:46:57 Etc/GMT",
        "purchase_date_pst": "2016-10-29 15:46:57 America/Los_Angeles",
        "bid": "test.myapp",
        "original_purchase_date_ms": "1477781217000",
        "in_app": [
            {
                "quantity": "1",
                "product_id": "abc",
                "transaction_id": "120000265421254",
                "original_transaction_id": "120000257973875",
                "purchase_date": "2016-10-30 04:46:42 Etc/GMT",
                "purchase_date_ms": "1477802802000",
                "purchase_date_pst": "2016-10-29 21:46:42 America/Los_Angeles",
                "original_purchase_date": "2016-10-29 22:46:57 Etc/GMT",
                "original_purchase_date_ms": "1477781217000",
                "original_purchase_date_pst": "2016-10-29 15:46:57 America/Los_Angeles",
                "expires_date": "2016-11-30 05:46:42 Etc/GMT",
                "expires_date_ms": "1480484802000",
                "expires_date_pst": "2016-11-29 21:46:42 America/Los_Angeles",
                "web_order_line_item_id": "820817285",
                "is_trial_period": "false"
            },
        ]
    },
    "latestReceiptInfo": [
        {
            "quantity": "1",
            "product_id": "abc",
            "transaction_id": "120000233230473",
            "original_transaction_id": "120000233230473",
            "purchase_date": "2016-06-12 22:36:58 Etc/GMT",
            "purchase_date_ms": "1465771018000",
            "purchase_date_pst": "2016-06-12 15:36:58 America/Los_Angeles",
            "original_purchase_date": "2016-06-12 22:36:58 Etc/GMT",
            "original_purchase_date_ms": "1465771018000",
            "original_purchase_date_pst": "2016-06-12 15:36:58 America/Los_Angeles",
            "expires_date": "2016-07-12 22:36:58 Etc/GMT",
            "expires_date_ms": "1468363018000",
            "expires_date_pst": "2016-07-12 15:36:58 America/Los_Angeles",
            "web_order_line_item_id": "120000034778618",
            "is_trial_period": "true"
        },
    ],
    "pendingRenewalInfo": [
        {
          "expiration_intent": "1",
            "auto_renew_product_id": "abc",
            "original_transaction_id": "120000233230473",
            "is_in_billing_retry_period": "0",
            "product_id": "abc",
            "auto_renew_status": "0"
        }
    ],
    "transactionId": "120000233230473",
    "productId": "abc",
    "platform": "apple",
    "environment": "production"
}

Google Play

The payment object

The receipt string is the purchase token that Google Play returns to the mobile application when a purchase is made.

Both packageName and productId are compulsory.

Lastly you must provide keyObject which is the Google API Service Account JSON key file linked to your Google Play account for authentication. This property can be either a string, file buffer or an object. If provided a string or file buffer, the call will automatically parse it into an object for use.

The response

The response passed back to your callback will also be Google Play specific. The entire parsed response will be in the receipt sub-object.

{
        "receipt": {
                "kind": "androidpublisher#productPurchase",
                "purchaseTimeMillis": "1410835105408",
                "purchaseState": 0,
                "consumptionState": 1,
                "developerPayload": ""
        },
        "transactionId": "ghbbkjheodjokkipdmlkjajn.AO-J1OwfrtpJd2fkzzZqv7i107yPmaUD9Vauf9g5evoqbIVzdOGYyJTSEMhSTGFkCOzGtWccxe17dtbS1c16M2OryJZPJ3z-eYhEJYiSLHxEZLnUJ8yfBmI",
        "productId": "abc",
        "platform": "google"
}

Roku

The receiept string represents the transaction returned from a channel or product purchase.

A developer ID is required.

The response

The response passed back to your callback will also be Roku specific. The entire parsed receipt will be in the result object:

{
    "receipt": {
        "errorCode": null,
        "errorDetails": null,
        "errorMessage": "",
        "status": 0,
        "amount": 4.99,
        "cancelled": false,
        "channelId": 70391,
        "channelName": "abc",
        "couponCode": null,
        "currency": "usd",
        "expirationDate": 1488337344000,
        "originalPurchaseDate": 1483153344000,
        "partnerReferenceId": null,
        "productId": "5KAZUPGB.0RF0",
        "productName": "BASIC - US MONTHLY",
        "purchaseDate": 1483153344000,
        "quantity": 1,
        "rokuCustomerId": "5e56c4c4d7d1504f813c630c2790e54a",
        "tax": 0,
        "total": 0,
        "transactionId": "380e9932-ed9a-48e8-bd66-a6ec00b5efd1"
    },
    "transactionId": "380e9932-ed9a-48e8-bd66-a6ec00b5efd1",
    "productId": "abc",
    "platform": "roku"
}

All Platforms

Regardless of the platform used, besides the platform-specific receipt, the following properties will be included:

Property	Type	Description
receipt	object	Data returned by platforms
platform	string	One of: 'apple', 'google', 'amazon', 'roku'
productId	string	Id of the product
transactionId	string	Id to uniquely identify transaction
purchaseDate	int	Date of purchase in millis
expirationDate	int	Date of expiration in millis

License

MIT

References

Amazon References

Code Inspiration

• https://github.com/may215/amazon_iap

API Reference

• https://developer.amazon.com/public/apis/earn/in-app-purchasing/docs-v2/verifying-receipts-in-iap

Apple References

Code Inspiration

• https://github.com/pcrawfor/iap_verifier

API Reference

• https://developer.apple.com/library/ios/releasenotes/General/ValidateAppStoreReceipt/Chapters/ValidateRemotely.html

Google Play References

Code Inspiration

• https://www.npmjs.com/package/google-play-purchase-validator
• https://github.com/machadogj/node-google-bigquery
• https://github.com/extrabacon/google-oauth-jwt/blob/master/lib/request-jwt.js

API Reference

• https://developer.android.com/google/play/billing/gp-purchase-status-api.html
• https://developers.google.com/android-publisher/
• https://developers.google.com/android-publisher/getting_started
• https://developers.google.com/android-publisher/authorization
• https://developers.google.com/accounts/docs/OAuth2ServiceAccount
• https://developers.google.com/android-publisher/api-ref/purchases/products
• https://developers.google.com/android-publisher/api-ref/purchases/products/get
• http://developer.android.com/google/play/billing/billing_testing.html
• http://stackoverflow.com/questions/24323207/use-service-account-to-verify-google-inapppurchase

Receipt Generation

• http://developer.android.com/training/in-app-billing/preparing-iab-app.html
• http://developer.android.com/tools/publishing/app-signing.html
• http://developer.android.com/google/play/billing/api.html#managed

Roku References

API Reference

• https://sdkdocs.roku.com/display/sdkdoc/Web+Service+API#WebServiceAPI-/listen/transaction-service.svc/validate-transaction/{devtoken}/{transactionid}