Google Pay

Overview

Google Pay is a digital wallet that allows customers to make online payments using payment cards stored in their Google Account.

Through Lemonway's integration, partners can offer Google Pay directly on their checkout page. Customers select Google Pay, choose an available payment card and confirm the payment through Google's payment interface.

Lemonway acts as the payment gateway, receiving and processing the payment information returned by Google Pay.

This integration supports desktop and mobile web browsers. Native Android application integration is not covered by this guide.

For the technical implementation, see the Google Pay API Reference.

How does the payment work?

The Google Pay integration involves three parties:

Partner platform: Displays the Google Pay button and initiates the payment.
Google Pay: Provides the payment interface and returns the payment data after customer confirmation.
Lemonway: Creates the payment session, receives the Google Pay payment data and processes the transaction.

Payment journey

The customer selects Google Pay on the partner's checkout page.
The partner initiates a card payment session with Lemonway using POST /moneyins/card/webinit.
Lemonway returns a webkitToken to identify the payment session.
The customer confirms the payment through the Google Pay interface.
Google Pay returns a PaymentData object containing the payment information.
The partner sends this information, together with the webkitToken, to Lemonway using POST /direct-payments/xpay/google/.
Lemonway processes the payment and handles the required authentication.
The partner retrieves or receives the final transaction status through its configured payment-status handling process.

The partner must use the final transaction status to determine whether the payment was successful.

Prerequisites

Before integrating Google Pay, the partner must complete the following steps:

Activate Google Pay with Lemonway

Contact your Lemonway account manager to activate Google Pay for your solution. Lemonway will provide the solution name required for the integration.

Register with Google

Create a business profile in the Google Pay & Wallet Console and submit your website domain for approval. Google will provide a Google Merchant ID once the registration process is complete.

Configure the checkout page

Add the Google Pay button to your checkout page and configure the payment request using the Google Pay JavaScript API.

The integration must include the Lemonway gateway configuration and the merchant information provided during onboarding.

Payment processing and authentication

Google Pay can return different types of payment credentials. Lemonway handles 3D Secure (3DS) according to the credential type received.

CRYPTOGRAM_3DS: Authentication has already been performed by Google. Lemonway processes the payment without an additional 3DS challenge.
PAN_ONLY: Lemonway automatically triggers additional 3DS authentication before processing the payment. The customer may be asked to complete a 3DS challenge.

No additional 3DS configuration is required specifically for Google Pay.

Important information

Google Pay must be activated on your Lemonway account before transactions can be processed.
Your website domain must be registered and approved by Google for production use.
The Google Merchant ID and Lemonway solution name are two different identifiers. Make sure you use each in the correct configuration field.
Billing address information is not required by Lemonway by default. It can be requested through the Google Pay payment request if needed.
If your website uses a Content Security Policy (CSP), it must allow the Google Pay script and frame sources.
This integration covers web and mobile web checkout, not native Android applications.

Technical documentation

For the complete technical implementation, including request parameters, configuration examples and API calls, refer to: