Accept a PayPal payment

First, you need a Stripe account. Register now.

Server-side

This integration requires endpoints on your server that talk to the Stripe API. Use the official libraries for access to the Stripe API from your server:

# Available as a gem
sudo gem install stripe

# If you use bundler, you can add this line to your Gemfile
gem 'stripe'

Client-side

The Stripe iOS SDK is open source, fully documented, and compatible with apps supporting iOS 13 or above.

Configure the SDK with your Stripe publishable key on app start. This enables your app to make requests to the Stripe API.

import UIKit
import StripePaymentsUI

@main
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        StripeAPI.defaultPublishableKey = 
"pk_test_TYooMQauvdEDq54NiTphI7jx"
        // do any other necessary launch configuration
        return true
    }
}

Server-side

Stripe uses a payment object, called a PaymentIntent, to track and handle all the states of the payment until it’s completed. Create a PaymentIntent on your server, specifying the amount to collect and the currency. If you already have an integration using the Payment Intents API, add paypal to the list of payment method types for your PaymentIntent.

curl https://api.stripe.com/v1/payment_intents \
  -u "
sk_test_BQokikJOvBiI2HlWgH4olfQ2
:" \
  -d amount=1099 \
  -d currency=eur \
  -d "payment_method_types[]"=paypal

Included in the returned PaymentIntent is a client secret, which is used to securely complete the payment process instead of passing the entire PaymentIntent object. Send the client secret back to the client so you can use it in later steps.

Include a custom description

By default, the order details on the PayPal users purchase activity page displays the order amount. You can change this by providing a custom description in the description property.

curl https://api.stripe.com/v1/payment_intents \
  -u "
sk_test_BQokikJOvBiI2HlWgH4olfQ2
:" \
  -d amount=1099 \
  -d currency=eur \
  -d description="A sample description" \
  -d "payment_method_types[]"=paypal

Customize the preferred locale

By default, the PayPal authorization page is localized based on variables such as the merchant’s country. You can set this to your customer’s preferred locale using the preferred_locale property. The value must be a two-character lowercased language code, followed by a hyphen (-), followed by a two-character uppercased country code. For example, the value for a French-language user in Belgium would be fr-BE. See supported locales for more information.

curl https://api.stripe.com/v1/payment_intents \
  -u "
sk_test_BQokikJOvBiI2HlWgH4olfQ2
:" \
  -d amount=1099 \
  -d currency=eur \
  -d "payment_method_types[]"=paypal \
  -d "payment_method_options[paypal][preferred_locale]"=fr-BE

Statement descriptors with PayPal

The descriptor that appears on the buyer’s bank statement is set by PayPal, and by default is PAYPAL *YOUR_BUSINESS_NAME. If you set the statement_descriptor field when creating the PaymentIntent, its value is appended to the one set by PayPal, up to a total limit of 22 characters.

For example, if your business name in PayPal is BUSINESS and you set statement_descriptor to order_id_1234, buyers see PAYPAL *BUSINESS order on their bank account statement.

Client-side

On the client, request a PaymentIntent from your server and store its client secret.

class CheckoutViewController: UIViewController {
    var paymentIntentClientSecret: String?

    // ...continued from previous step

    override func viewDidLoad() {
        // ...continued from previous step
        startCheckout()
    }

    func startCheckout() {
        // Request a PaymentIntent from your server and store its client secret
        // Click View full sample to see a complete implementation
    }
}

When a customer taps to pay with PayPal, confirm the PaymentIntent to complete the payment. Configure an STPPaymentIntentParams object with the PaymentIntent client secret.

The client secret is different from your API keys that authenticate Stripe API requests. Handle this carefully as it can complete the charge. Don’t log it, embed it in URLs, or expose it to anyone but the customer.

Set up a return URL

The iOS SDK presents a webview in your app to complete the PayPal payment. When authentication is finished, the webview can automatically dismiss itself instead of having your customer close it. To enable this behavior, configure a custom URL scheme or universal link and set up your app delegate to forward the URL to the SDK.

// This method handles opening custom URL schemes (for example, "your-app://stripe-redirect")
func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
    let stripeHandled = StripeAPI.handleURLCallback(with: url)
    if (stripeHandled) {
        return true
    } else {
        // This was not a Stripe url – handle the URL normally as you would
    }
    return false
}

// This method handles opening universal link URLs (for example, "https://example.com/stripe_ios_callback")
func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void) -> Bool {
    if userActivity.activityType == NSUserActivityTypeBrowsingWeb {
        if let url = userActivity.webpageURL {
            let stripeHandled = StripeAPI.handleURLCallback(with: url)
            if (stripeHandled) {
                return true
            } else {
                // This was not a Stripe url – handle the URL normally as you would
            }
        }
    }
    return false
}

Pass the URL as the return_url when you confirm the PaymentIntent. After webview-based authentication is finished, Stripe redirects the user to the return_url.

Confirm PayPal payment

Complete the payment by calling STPPaymentHandler confirmPayment. This presents a webview where the customer can complete the payment with PayPal. Upon completion, the completion block is called with the result of the payment.

let paymentIntentParams = STPPaymentIntentParams(clientSecret: paymentIntentClientSecret)

// PayPal does not require additional parameters so we only need to pass the initialized
// STPPaymentMethodPayPalParams instance to STPPaymentMethodParams
let payPal = STPPaymentMethodPayPalParams()
let paymentMethodParams = STPPaymentMethodParams(payPal: payPal, billingDetails: nil, metadata: nil)

paymentIntentParams.paymentMethodParams = paymentMethodParams

STPPaymentHandler.shared().confirmPayment(paymentIntentParams,
                                          with: self)
{ (handlerStatus, paymentIntent, error) in
    switch handlerStatus {
    case .succeeded:
        // Payment succeeded
        // ...

    case .canceled:
        // Payment canceled
        // ...

    case .failed:
        // Payment failed
        // ...

    @unknown default:
        fatalError()
    }
}

You can find the payment owner’s name, email, payer ID, and transaction ID in the payment_method_details property.

{
  "charges": {
    "data": [
      {
        "payment_method_details": {
          "paypal": {
            "payer_id": "H54KFE9XXVVYJ",
            "payer_email": "jenny@example.com",
            "payer_name": "Jenny Rosen",
            "transaction_id": "89W40396MK104212M"
          },
          "type": "paypal"
        },
        "id": "src_16xhynE8WzK49JbAs9M21jaR",
        "object": "source",
        "amount": 1099,
        "client_secret": "src_client_secret_UfwvW2WHpZ0s3QEn9g5x7waU",
        "created": 1445277809,
        "currency": "eur",
        "flow": "redirect",