<script>
/**
* Define the version of the Google Pay API referenced when creating your
* configuration
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#PaymentDataRequest|apiVersion in PaymentDataRequest}
*/
const baseRequest = {
apiVersion: 2,
apiVersionMinor: 0
};
/**
* Card networks supported by your site and your gateway
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#CardParameters|CardParameters}
* @todo confirm card networks supported by your site and gateway
*/
const allowedCardNetworks = ["AMEX", "DISCOVER", "INTERAC", "JCB", "MASTERCARD", "VISA"];
/**
* Card authentication methods supported by your site and your gateway
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#CardParameters|CardParameters}
* @todo confirm your processor supports Android device tokens for your
* supported card networks
*/
const allowedCardAuthMethods = ["PAN_ONLY", "CRYPTOGRAM_3DS"];
/**
* Identify your gateway and your site's gateway merchant identifier
*
* The Google Pay API response will return an encrypted payment method capable
* of being charged by a supported gateway after payer authorization
*
* @todo check with your gateway on the parameters to pass
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#gateway|PaymentMethodTokenizationSpecification}
*/
const tokenizationSpecification = {
type: 'PAYMENT_GATEWAY',
parameters: {
'gateway': 'example',
'gatewayMerchantId': 'exampleGatewayMerchantId'
}
};
/**
* Describe your site's support for the CARD payment method and its required
* fields
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#CardParameters|CardParameters}
*/
const baseCardPaymentMethod = {
type: 'CARD',
parameters: {
allowedAuthMethods: allowedCardAuthMethods,
allowedCardNetworks: allowedCardNetworks
}
};
/**
* Describe your site's support for the CARD payment method including optional
* fields
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#CardParameters|CardParameters}
*/
const cardPaymentMethod = Object.assign(
{},
baseCardPaymentMethod,
{
tokenizationSpecification: tokenizationSpecification
}
);
/**
* An initialized google.payments.api.PaymentsClient object or null if not yet set
*
* @see {@link getGooglePaymentsClient}
*/
let paymentsClient = null;
/**
* Configure your site's support for payment methods supported by the Google Pay
* API.
*
* Each member of allowedPaymentMethods should contain only the required fields,
* allowing reuse of this base request when determining a viewer's ability
* to pay and later requesting a supported payment method
*
* @returns {object} Google Pay API version, payment methods supported by the site
*/
function getGoogleIsReadyToPayRequest() {
return Object.assign(
{},
baseRequest,
{
allowedPaymentMethods: [baseCardPaymentMethod]
}
);
}
/**
* Configure support for the Google Pay API
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#PaymentDataRequest|PaymentDataRequest}
* @returns {object} PaymentDataRequest fields
*/
function getGooglePaymentDataRequest() {
const paymentDataRequest = Object.assign({}, baseRequest);
paymentDataRequest.allowedPaymentMethods = [cardPaymentMethod];
paymentDataRequest.transactionInfo = getGoogleTransactionInfo();
paymentDataRequest.merchantInfo = {
// @todo a merchant ID is available for a production environment after approval by Google
// See {@link https://developers.google.com/pay/api/web/guides/test-and-deploy/integration-checklist|Integration checklist}
// merchantId: '01234567890123456789',
merchantName: 'Example Merchant'
};
paymentDataRequest.callbackIntents = ["PAYMENT_AUTHORIZATION"];
return paymentDataRequest;
}
/**
* Return an active PaymentsClient or initialize
*
* @see {@link https://developers.google.com/pay/api/web/reference/client#PaymentsClient|PaymentsClient constructor}
* @returns {google.payments.api.PaymentsClient} Google Pay API client
*/
function getGooglePaymentsClient() {
if ( paymentsClient === null ) {
paymentsClient = new google.payments.api.PaymentsClient({
environment: 'TEST',
paymentDataCallbacks: {
onPaymentAuthorized: onPaymentAuthorized
}
});
}
return paymentsClient;
}
/**
* Handles authorize payments callback intents.
*
* @param {object} paymentData response from Google Pay API after a payer approves payment through user gesture.
* @see {@link https://developers.google.com/pay/api/web/reference/response-objects#PaymentData object reference}
*
* @see {@link https://developers.google.com/pay/api/web/reference/response-objects#PaymentAuthorizationResult}
* @returns Promise<{object}> Promise of PaymentAuthorizationResult object to acknowledge the payment authorization status.
*/
function onPaymentAuthorized(paymentData) {
return new Promise(function(resolve, reject){
// handle the response
processPayment(paymentData)
.then(function() {
resolve({transactionState: 'SUCCESS'});
})
.catch(function() {
resolve({
transactionState: 'ERROR',
error: {
intent: 'PAYMENT_AUTHORIZATION',
message: 'Insufficient funds, try again. Next attempt should work.',
reason: 'PAYMENT_DATA_INVALID'
}
});
});
});
}
/**
* Initialize Google PaymentsClient after Google-hosted JavaScript has loaded
*
* Display a Google Pay payment button after confirmation of the viewer's
* ability to pay.
*/
function onGooglePayLoaded() {
const paymentsClient = getGooglePaymentsClient();
paymentsClient.isReadyToPay(getGoogleIsReadyToPayRequest())
.then(function(response) {
if (response.result) {
addGooglePayButton();
}
})
.catch(function(err) {
// show error in developer console for debugging
console.error(err);
});
}
/**
* Add a Google Pay purchase button alongside an existing checkout button
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#ButtonOptions|Button options}
* @see {@link https://developers.google.com/pay/api/web/guides/brand-guidelines|Google Pay brand guidelines}
*/
function addGooglePayButton() {
const paymentsClient = getGooglePaymentsClient();
const button =
paymentsClient.createButton({onClick: onGooglePaymentButtonClicked});
document.getElementById('container').appendChild(button);
}
/**
* Provide Google Pay API with a payment amount, currency, and amount status
*
* @see {@link https://developers.google.com/pay/api/web/reference/request-objects#TransactionInfo|TransactionInfo}
* @returns {object} transaction info, suitable for use as transactionInfo property of PaymentDataRequest
*/
function getGoogleTransactionInfo() {
return {
displayItems: [
{
label: "Subtotal",
type: "SUBTOTAL",
price: "11.00",
},
{
label: "Tax",
type: "TAX",
price: "1.00",
}
],
countryCode: 'US',
currencyCode: "USD",
totalPriceStatus: "FINAL",
totalPrice: "12.00",
totalPriceLabel: "Total"
};
}
/**
* Show Google Pay payment sheet when Google Pay payment button is clicked
*/
function onGooglePaymentButtonClicked() {
const paymentDataRequest = getGooglePaymentDataRequest();
paymentDataRequest.transactionInfo = getGoogleTransactionInfo();
const paymentsClient = getGooglePaymentsClient();
paymentsClient.loadPaymentData(paymentDataRequest);
}
let attempts = 0;
/**
* Process payment data returned by the Google Pay API
*
* @param {object} paymentData response from Google Pay API after user approves payment
* @see {@link https://developers.google.com/pay/api/web/reference/response-objects#PaymentData|PaymentData object reference}
*/
function processPayment(paymentData) {
return new Promise(function(resolve, reject) {
setTimeout(function() {
// @todo pass payment token to your gateway to process payment
paymentToken = paymentData.paymentMethodData.tokenizationData.token;
if (attempts++ % 2 == 0) {
reject(new Error('Every other attempt fails, next one should succeed'));
} else {
resolve({});
}
}, 500);
});
}
</script>
