Enable Apple Pay

Use the following step-by-step instructions to integrate Apple Pay with the In-App Payments SDK on an iOS device. It also shows how to integrate and test the Apple Pay digital wallet in the Square Sandbox and how to move the integration into production. Digital wallet payments with Apple Pay are available in all regions in which Square operates.

• You've followed the instructions in Build on iOS. This topic doesn't cover the general setup of the In-App Payments SDK.
• You've added your Apple developer account to Xcode.
• The deployment target for your application is iOS 10.0 or later.
• Testing requires a physical iOS device with a valid card registered in your Apple Pay wallet. The iOS Simulator is not supported.

To add an Apple Pay payment processing certificate in the Apple Developer Portal, you must first obtain a Certificate Signing Request (CSR) from Square. The Square Developer Console provides a CSR file that can be submitted to Apple:

1. Choose the application you created for your In-App Payments SDK application.
2. At the top of the page, choose Sandbox mode.
3. In the left pane, choose Apple Pay.
4. Choose Add Sandbox Certificate and follow the instructions to generate an Apple Pay certificate.

A single In-App Payments SDK application associated with a Payment Processing Certificate and Apple Pay merchant ID might be listed multiple times in the Apple Store.

1. Open your project in Xcode.
2. In the Navigator Area, choose your project file, and then choose the SDK integration target in the editor area.
3. Choose the Capabilities tab, and then enable Apple Pay by sliding the capability toggle to ON.
4. Select the box adjacent to the merchant ID you added to trigger an automatic Xcode process that completes the three Apple Pay configuration steps.

Update REPLACE_ME in the following code with your Square application ID. If you don't set your Square application ID before initializing SQIPCardEntryViewController, your application terminates with an uncaught exception.

import SquareInAppPaymentsSDK

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    func application(_: UIApplication,
                     didFinishLaunchingWithOptions _:
                     [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        // Set your Square Application ID
        SQIPInAppPaymentsSDK.squareApplicationID = "<# REPLACE_ME #>"
        return true
    }
}

Replace <# REPLACE_ME #> with your application ID. For example, the application ID sq0ids-KHbh5gEaJuH7GEi1lgGMBQ replaces the placeholder as shown in the following code:

SQIPInAppPaymentsSDK.squareApplicationID = "sq0ids-KHbh5gEaJuH7GEi1lgGMBQ"

1. Add the following extension (@implementation for Objective C) to your view controller.
2. Paste the merchant ID associated with the Apple Pay certificate from step 1 into the PKPaymentRequest constructor to replace <#REPLACE_ME#>.

import PassKit
import SquareInAppPaymentsSDK

extension<#YourViewController#> {
    func requestApplePayAuthorization() {
        guard SQIPInAppPaymentsSDK.canUseApplePay else {
            return
        }
        let paymentRequest = PKPaymentRequest.squarePaymentRequest(
            // Set to your Apple merchant ID
            merchantIdentifier: <#REPLACE_ME#>,
            countryCode: "US",
            currencyCode: "USD"
        )

        // Payment summary information will be displayed on the Apple Pay sheet.
        paymentRequest.paymentSummaryItems = [
            PKPaymentSummaryItem(label: "Testing Apple Pay", amount: 1.00),
        ]

        let paymentAuthorizationViewController =
            PKPaymentAuthorizationViewController(paymentRequest: paymentRequest)

        paymentAuthorizationViewController!.delegate = self

        present(paymentAuthorizationViewController!, animated: true, completion: nil)
    }
}

Extend your view controller by adding two delegate methods. The two delegate methods that you implement let you handle the following events:

• didAuthorizePayment - A buyer-submitted payment card and the payment authorization sheet created a PKPpayment object. This method is invoked by the PassKit framework while the payment authorization sheet is still open.
• didFinish - This method is invoked after the didAuthorizePayment completion handler is invoked by your code and the result is displayed to the buyer, or after the buyer cancels payment authorization.

If the buyer authorizes payment, a PKPayment object is returned and can be used in step 6 to get a Square payment token.

import PassKit

extension<#YourViewController#>: PKPaymentAuthorizationViewControllerDelegate {
    func paymentAuthorizationViewController(
        _: PKPaymentAuthorizationViewController,
        didAuthorizePayment _: PKPayment,
        handler _: @escaping (
            PKPaymentAuthorizationResult) -> Void
    ) {
        // TODO: Add payment->nonce exchange logic. See Step 5: Request a Square
        // nonce
    }

    func paymentAuthorizationViewControllerDidFinish(
        _: PKPaymentAuthorizationViewController
    ) {
        dismiss(animated: true, completion: nil)
    }
}

If the buyer authorizes payment, the PassKit framework calls your paymentAuthorizationViewController(_:didAuthorizePayment:handler:) delegate method.

1. Create a SQIPApplePayNonceRequest object with the supplied PKPayment object to request a payment token.
2. Call the SQIPApplePayNonceRequest performWithCompletionHandler method to request a payment token.

After a payment token is received, send it to your backend to charge or store the card through Square.

You can indicate a success or failure by invoking the handler provided to the paymentAuthorizationViewController(_:didAuthorizePayment:handler:) method with the appropriate parameters. This allows the Apple Pay payment sheet to display the appropriate UI to the buyer to notify them of the result.

func paymentAuthorizationViewController(
    _: PKPaymentAuthorizationViewController,
    didAuthorizePayment payment: PKPayment,
    handler completion: @escaping (
        PKPaymentAuthorizationResult) -> Void
) {
    // Exchange the authorized PKPayment for a nonce.
    let nonceRequest = SQIPApplePayNonceRequest(payment: payment)
    nonceRequest.perform { cardDetails, error in
        if let cardDetails = cardDetails {
            // Send the card nonce to your server to charge the card or store
            // the card on file.

            /*
             MyAPIClient.shared.chargeCard(withNonce: cardDetails.nonce) {
                 transaction, chargeEerror in

                 if let chargeError = chargeError {
                     completion(PKPaymentAuthorizationResult(status: .failure,
                     errors: [chargeError]))
                 }
                 else {
                     completion(PKPaymentAuthorizationResult(status: .success,
                     errors: nil))
                 }
             }
             */

            completion(PKPaymentAuthorizationResult(status: .success, errors: nil))
        } else if let error = error {
            print(error)
            completion(PKPaymentAuthorizationResult(status: .failure, errors: [error]))
        }
    }
}

To test your Apple Pay integration, you must register a valid credit card in your Apple Pay wallet.

Testing your Apple Pay integration involves the following steps:

1. Choose the Apple Pay button and complete the payment sheet that opens.
2. Verify that you're receiving a payment token in the didObtainCardDetails callback.

The payment token generated for Apple Pay can be used to take a payment with the Payments API in the Square Sandbox.

When your application is ready for production, do the following:

1. Register a production certificate for Apple Pay in iOS:
   1. Open the Developer Console.
   2. Choose the application associated with your In-App Payments SDK implementation.
   3. Set the Developer Console to Production mode.
   4. In the left pane, choose Apple Pay for the selected application.
   5. Create a new Apple Pay merchant ID to be used in the next step.
   6. Choose Add Certificate under iOS and follow the instructions.
2. Replace the Sandbox application ID in your application with the production application ID.
3. Replace the Sandbox merchant ID set in step 4 with the new production merchant ID.