RMStore

A lightweight iOS framework for In-App Purchases.

RMStore adds blocks and notifications to StoreKit, plus receipt verification and purchase management. All in one class without external dependencies. Purchasing a product is as simple as:

[[RMStore defaultStore
 
] addPayment:productID success:^(SKPaymentTransaction *transaction) {
    NSLog(@"Purchased!", @"");
} failure:^(SKPaymentTransaction *transaction, NSError *error) {
    NSLog(@"Something went wrong", @"");
}];

Add RMStore to your project

1. Link StoreKit.framework
2. Profit!

StoreKit with blocks

RMStore adds blocks to all asynchronous StoreKit operations.

Requesting products

NSSet *products = [NSSet setWithArray:@[@"fabulousIdol", @"rootBeer", @"rubberChicken"]];
[[RMStore defaultStore] requestProducts:products success:^(NSArray *products, NSArray *invalidProductIdentifiers) {
    NSLog(@"Products loaded", @"");
} failure:^(NSError *error) {
    NSLog
 
(@"Something went wrong", @"");
}];

Add payment

[[RMStore defaultStore] addPayment:@"waxLips" success:^(SKPaymentTransaction *transaction) {
    NSLog(@"Product purchased", @"");
} failure:^(SKPaymentTransaction *transaction, NSError *error) {
    NSLog(@"Something went wrong", @"");
}];

Restore transactions

[[RMStore defaultStore] restoreTransactionsOnSuccess:^{
    NSLog(@"Transactions restored", @"");
} failure:^(NSError *error) {
    NSLog(@"Something went wrong", @"");
}];

Notifications

RMStore sends notifications of StoreKit related events and extends NSNotification to provide relevant information. To receive them, implement the desired methods of the RMStoreObserver protocol and add the observer to RMStore.

Adding and removing the observer

[[RMStore defaultStore] addStoreObserver:self];
...
[[RMStore defaultStore] removeStoreObserver:self];

Products request notifications

- (void)storeProductsRequestFailed:(NSNotification*)notification
{
    NSError *error = notification.storeError;
}

- (void)storeProductsRequestFinished:(NSNotification*)notification 
{
    NSArray *products = notification.products;
    NSArray *invalidProductIdentifiers = notification.invalidProductIdentififers;
}

Payment transaction notifications

Payment transaction notifications are sent after a payment has been requested or for each restored transaction.

- (void)storePaymentTransactionFailed:(NSNotification*)notification
{
    NSError *error = notification.storeError;
    NSString *productIdentifier = notification.productIdentifier;
    SKPaymentTransaction *transaction = notification.transaction;
}

- (void)storePaymentTransactionFinished:(NSNotification*)notification
{
    NSString *productIdentifier = notification.productIdentifier;
    SKPaymentTransaction *transaction = notification.transaction;
}

Restore transactions notifications

- (void)storeRestoreTransactionsFailed:(NSNotification*)notification;
{
    NSError *error = notification.storeError;
}

- (void)storeRestoreTransactionsFinished:(NSNotification*)notification { }

Receipt verification

While RMStore doesn't perform receipt verification by default, you can provide your own custom verification or use the app-side verification provided by the framework.

App-side verification

RMStore provides optional app-side receipt verification via RMStoreLocalReceiptVerificator. To use it, addRMStoreLocalReceiptVerificator.h and RMStoreLocalReceiptVerificator.m to your project and set the verification delegate (receiptVerificator) at startup. For example:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    _receiptVerificator = [[RMStoreLocalReceiptVerificator alloc] init]; // Keep a reference to the verificator as the below property is weak
    [RMStore defaultStore].receiptVerificator = _receiptVerificator;
    // Your code
    return YES;
}

Custom verification

Apple strongly recommends to use your own server-side verification. To do this, implement theRMStoreReceiptVerificator protocol:

- (void)verifyReceiptOfTransaction:(SKPaymentTransaction*)transaction
                           success:(void (^)())successBlock
                           failure:(void (^)(NSError *error))failureBlock;

In most cases you will call a web service that performs the same logic than RMStoreLocalReceiptVerificator, but on your server. Call successBlock if the receipt passes verification, and failureBlock in any other case.

You will also need to set the receiptVerificator delegate at startup, as indicated above.

Purchase management

RMStore stores transactions in NSUserDefaults with weak obfuscation and allows you to implement your own. It also offers various methods to query and manage purchases.

Below are the most common use cases related to purchases.

Working with non-consumables

Non-consumables can only be purchased once. To know if a non-consumable has been purchased:

BOOL purchased = [[RMStore defaultStore] isPurchasedForIdentifier:@"fabulousIdol"];

Working with consumables

Consumables can be purchased more than once and tipically will be consumed at most once per purchase. Here is how you would normally operate with a non-consumable:

NSInteger purchaseCount = [[RMStore defaultStore] countPurchasesForIdentifier:@"banana"];
if (purchaseCount > 0)
{
    BOOL success = [[RMStore defaultStore] consumeProductForIdentifier:@"banana"];
}

Managing purchases manually

In some cases you might want to bypass payment with StoreKit and mark a product as purchased manually (e.g., for promotional purposes). You can do this with:

[[RMStore defaultStore] addPurchaseForProductIdentifier:@"breathMints"];

Obfuscation

By default RMStore stores transactions in NSUserDefaults as objects using NSCoding, as a form of weak obfuscation. It is recommended to provide your own custom obfuscation by implementing theRMStoreTransactionObfuscator protocol and setting the transactionObfuscator delegate at startup.

You will be obfuscating RMStoreTransaction instances, an analogue of SKPaymentTransaction which supports NSCopying, unlike the original.

Requirements

RMStore requires iOS 5.0 or above and ARC.

If you are using RMStore in your non-ARC project, you will need to set a -fobjc-arc compiler flag on all of the RMStore source files.

For iOS 5.x

There is a known vulnerability in iOS 5.1 or lower related to app-side receipt verification. RMStore does not address this vulnerability. If you are using RMStoreLocalReceiptVerificator in iOS 5.x, please read thistechnical note.

Roadmap

RMStore is in early stage and currently supports consumables and non-consumables only. Future enhancements will include:

• Content download support
• Subcriptions support
• OS X support

If you are looking for something more mature, check out CargoBay or MKStoreKit.

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.