StoreKit on Andrew Bancroft

StoreKit Testing Swift Start

Thu, 25 Jun 2020 00:00:00 +0000

Manually Testing StoreKit Code

Development Workflow Changes

The previous workflow for setting up in-app purchases was a bit disjointed.

You’d have to create your app in Xcode… then jump out to App Store Connect to define your app there… set up your digital products there (in App Store Connect)… and then jump back to Xcode to write your StoreKit code.

Now, you can get started in Xcode, and stay in Xcode. Here’s how:

Go to the File menu
Click New ➡️ File
Type “storekit” into the filter
Click Next to add a StoreKit Configuration File ✅

From there, you get to add the digital products you intend to offer in your app, all without leaving Xcode!

Xcode offers support for configuring all three product types:

Consumable
Non-Consumable
Auto-Renewable Subscription

‼️Note: It appears that Non-Renewing Subscriptions are no longer encouraged

Once you have all of your products configured and your Store view written, you’ll want to use your configuration for testing.

To do it, you need to edit your app’s scheme:

Click your app target in the toolbar
Click Edit Scheme…
Click Options
Find StoreKit Configuration, and select the configuration you’ve added for your project in the dropdown ✅

Making Test Purchases

Now to actually test things!

To test things locally, you don’t need to create a sandbox tester account first (something else you used to have to do before testing in-app purchases).

Everything happens locally.

All of your code that would be communicating with the App Store itself in Production, is “taken care of” by Xcode.

So you may be wondering…

❓"Do my SKPaymentTransactionObserver functions get executed when they’re supposed to?"

👉Yes.

❓"Do I get a receipt for the purchase?"

👉Yes.

❓"Can I use that receipt to validate successfully?"

👉Kinda. Receipts from the local Xcode environment are not signed with the same signature as the Sandbox and Production environments are, so they cannot be used if you’re implementing server-side receipt validation.

Development Workflow Enhancements

StoreKit Transaction Manager

How often does your implementation work perfectly the first time?

Rarely?

Yeah… I’m with you.

With the new StoreKit Transaction Manager, it’s easy to “clear things out” so that previous test purchases that didn’t go so well can be tried again fresh, as if a purchase never happened.

Note: If you don’t see the StoreKit Transaction Manager icon in the debug console, make sure you’ve added the In-App Purchasing capability to your app. Then try again.

Test Edge Cases

To support testing out what could be considered “edge cases” in the in-app purchasing experience, Xcode 12 also has the ability to simulate things like:

Time Rate for Auto-Renewable Subscription expiration
Interrupted purchases
Failed transactions
Ask To Buy

Auto-Renewable Subscription Testing Enhancements

Testing subscription expiration is important for preserving the revenue you intend to generate from auto-renewable subscriptions.

The challenge is that you and I don’t have time to wait!

Previously, you could update your product in App Store Connect to have a shorter duration, and the Sandbox environment would interpret, say, a six month subscription to be “30 minutes” worth of time.

But that’s still a long time to wait between making a subscription purchase, and trying out expiration logic, isn’t it?

Problem. Solved. Now you can select even shorter durations for testing subscription expiration using the Time Rate menu option in Xcode’s editor menu when you’re on the StoreKit configuration page.

Remember: To see this editor menu, you have to be in the StoreKit configuration file of your app.

If a second equals a day, and there’s 30ish days in a month, a six month subscription should expire and auto-renew in three-ish minutes now.

A huge help for impatient types like myself!

Automated Testing for StoreKit Code

Tired of launching your app and clicking around manually to test things out?

Not only is that tedious, you and I are bound to either miss something, or test inconsistently, leading to a potentially sub-par end-user experience.

Apple has given us a new StoreKitTest framework that you can use within XCTest!

Everything that you can point-and-click on is fully testable with unit and UI tests with zero human interaction.

To get started using this new framework, it’s import StoreKitTest.

Is the Sandbox Environment Still Useful?

Super useful.

Testing things out locally is amazingly powerful for getting you started, but before you deploy your app to the App Store and send it into review, you still have to…

Set up your products in App Store Connect … right now the Xcode configuration doesn’t get “pushed up” to App Store Connect, so it’s a double-entry world right now.
Set up a Sandbox tester account in App Store Connect so that you can…
Test out your in-app purchasing workflow and receipt validation logic with receipts signed by a “real” App Store environment (just like your TestFlight testers and your App Reviewer will use)

And if you’re using App Store server notifications to detect changes to auto-renewable subscriptions, you need to test those out as well.

So for all of these reasons, the Sandbox environment is still there, and is still useful.

Alas, some manual testing is still required, but can you imagine some of the possibilities for getting started with implementing in-app purchases, right in Xcode, on day zero of your project?

Implementing In-App Purchases on iOS

Tue, 09 Jun 2020 10:03:33 +0000

Monetizing apps is challenging. In this course, Implementing In-App Purchases on iOS, you’ll learn to offer digital products and services directly within your app as in-app purchases.

Resources

Implementing In-App Purchases on iOS

Course Outline

First, you’ll explore how to translate business requirements into digital products and configure them in App Store Connect and Xcode.

Next, you’ll discover how to build and test a store within your app using StoreKit.

Finally, you’ll learn how to make sure purchases made within your app are authentic, and unlock content that’s been purchased by your users.

When you’re finished with this course, you’ll have the skills and knowledge needed to implement in-app purchases on iOS!

1 – Preparing to Implement In-App Purchases

Prepare to implement in-app purchases by understanding what’s involved from a big picture standpoint.

You will learn to configure digital products in App Store Connect and Xcode to kick off your in-app purchase learning adventure.

Topics in this module include…

The Perks (And the Work) Ahead of You
First Things First - Checking off the Prerequisites
Matching Product Types to Business Requirements
Setting Up Products in App Store Connect
Setting Up an Auto-Renewable Subscription
Configuring an Xcode Project for In-App Purchases

2 – Building In-App Purchase Functionality with StoreKit

The focus of this module is on the StoreKit APIs for working with digital products and App Store Connect.

You will learn to build and test a fully-working store view that will support in-app purchases.

Topics in this module include…

Using StoreKit to Build In-App Purchase Functionality: A Roadmap
Retrieving a Set of Products for Purchase from the App Store
Displaying Products in a User Interface
Implementing a “Buy” Button
Preparing to Test Purchases by Setting up a Sandbox Tester Account
Making Test Purchases
Implementing a “Restore Purchases” Button

3 – Protecting Your Revenue by Verifying Purchase Authenticity

After all your hard work to implement in-app purchases, how awful would it be if malicious users stole the content you’ve labored to create?

In this module, you will learn to implement measures to protect revenue generated through in-app purchases by validating App Store receipts.

Receipt validation is a notoriously burdensome hassle. But it doesn’t have to be!

I will teach you how to implement server-side receipt validation from end-to-end with no third-party libraries, no complicated server setup, and no platform-specific proprietary tools.

Here’s the roadmap of topics incluced:

Verifying Purchase Authenticity by Validating App Store Receipts
Weighing Strategies for Receipt Validation
Charting the Course for Server-side Receipt Validation
Sending the Receipt from Your App to Your Server
Writing Server-side Code to Forward the Receipt to the App Store for Validation
Handling the Response from the App Store on Your Server
Accounting for the Sandbox Environment on Your Server
Handling the Response from Your Server in Your App
The Case of the Missing Receipt: Requesting a Refresh

4 – Unlocking Purchased Content

After a user makes a valid purchase, you’ve got to unlock the content they legitimately bought!

Each product type has its own nuances for how to unlock and provide the associated content though.

What do you need to think about, and what code do you need to write to make it happen?

To find out, you will explore these topics:

Analyzing Content-providing Logic by Product Type
Persisting Purchased Products Securely
Using the iOS Keychain
Keeping Track of Consumable Product Inventory
Managing Non-Renewing Subscriptions
Synchronizing Purchases Across Devices
Handling Auto-Renewable Subscriptions
Saving Non-Consumable Transactions
Preparing for App Store Review

Feedback Welcome!

From the beginning I set out to make the course I wish I had when I started learning to implement in-app purchases for my apps. My unwavering goal is to help you filter the noise and learn as efficiently as possible. My hope is that this course benefits you in your iOS development career!

I welcome feedback on this course, and on other iOS development courses you might be interested in seeing in the Pluralsight library. Happy learning!