Apple Pay integration - Swift

I am integrating apple pay. I am following applepay documentation. Here is my code.

import UIKit
import PassKit

class ApplePayViewController: UIViewController {

@IBOutlet var lblLoading : UILabel!
@IBOutlet var loader : UIActivityIndicatorView!

var totalAmount = "100.0"
let paymentRequest = PKPaymentRequest()
override func viewDidLoad() {
    super.viewDidLoad()
    // Set up the payment request
    paymentRequest.merchantIdentifier = "merchant.com.apple.example"
    paymentRequest.supportedNetworks = [.visa, .masterCard, .amex, .discover]
    paymentRequest.merchantCapabilities = .capability3DS
    paymentRequest.countryCode = "US"
    paymentRequest.currencyCode = "USD"
    
    // Add a payment item
    let item = PKPaymentSummaryItem(label: "Total", amount: NSDecimalNumber(string: totalAmount))
    paymentRequest.paymentSummaryItems = [item]
    
    // Check if the device is capable of making payments
    if PKPaymentAuthorizationViewController.canMakePayments() {
        let authorizationViewController = PKPaymentAuthorizationViewController(paymentRequest: paymentRequest)
        authorizationViewController?.delegate = self
        present(authorizationViewController!, animated: true, completion: nil)
    } else {
        SharedManager.showAlertWithMessage(title: NSLocalizedString("Sorry", comment: ""), alertMessage: "This device is not capable of making payments.", viewController: self)
    }
}}

extension ApplePayViewController: PKPaymentAuthorizationViewControllerDelegate {

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

func paymentAuthorizationViewController(_ controller: PKPaymentAuthorizationViewController, didAuthorizePayment payment: PKPayment, handler completion: @escaping (PKPaymentAuthorizationResult) -> Void) {
    // Verify the payment with your server
    // ...
    
    completion(PKPaymentAuthorizationResult(status: .success, errors: nil))
}}

In didAuthorizePayment delegate i dont know how to verify the payment with server. I cannot find any function or post data related to this in document. Can you help me with this.

Thank you

You need to have a payment processor (like Stripe) to actually do the transaction.

See this tutorial: https://www.kodeco.com/2113-apple-pay-tutorial-getting-started

It explains how to do this with Stripe.

In this function, if Stripe is successful, you will also have to tell your own backend all of the information it needs to actually send the product or whatever the user ordered.