How it works
When a user taps the Google Pay payment button, they see a payment sheet. It displays the payment methods they've saved to their Google Account and optional fields such as a shipping address. Users can then select a payment method quickly and provide a shipping address if required, or they can add new information.
Notice: For further information about the button solution for Google Pay, please see https://support.computop.com/hc/en-gb/articles/4559076653970-Apple-Pay-und-Google-Pay-button-solution-PaySSL-aspx?source=search.
In-app payment
The Google Pay API enables fast, simple checkout within your app, giving you convenient access to hundreds of millions of cards saved to Google Accounts worldwide.
These above screens represent a recommended Google Pay buy flow for a shopping cart experience.
These guidelines will help you implement Google Pay within your apps: https://developers.google.com/pay/api/android/guides/brand-guidelines.
Web payment
The Google Pay API enables fast, simple checkout on your website. This provides convenient access to hundreds of millions of cards that are saved to Google Accounts worldwide.
The above screens represent a recommended Google Pay buy flow for a shopping cart experience.
These guidelines will help you reference the Google Pay brand within your websites: https://developers.google.com/pay/api/web/guides/brand-guidelines.
Step by Step Set-Up Guide
Once you have decided to support Google Pay, there is a set of steps that need to be done. This guide is applicable for both, in-app and also web payments.
1. Verify if your Acquirer supports Google Pay, for the card networks supported and support for Android device tokens.
This information will be provided by Computop support team: Computop Helpdesk.
2. If you already do not have one, request creation of Computop Merchant ID, unique identifier that represents a merchant in Computop Paygate platform. You need to use Computop Merchant ID also in Google Pay API.
Please contact Computop support team: Computop Helpdesk.
3. Integrate Google Pay API: https://developers.google.com/pay/api/.
Apps: https://developers.google.com/pay/api/android/overview
Web: https://developers.google.com/pay/api/web/overview
a. For payment tokenization method, choose “GATEWAY”, with following values:
const tokenizationSpecification = {
type: “PAYMENT_GATEWAY”,
parameters: {
'gateway': 'computop',
'gatewayMerchantId': 'yourComputopMerchantID'
}
b. For supported payment card networks, choose the ones your acquirer is supporting:
const allowedCardNetworks = ["AMEX", "DISCOVER", "JCB", "MASTERCARD", "VISA"];
c. The Google Pay API may return cards on file on Google.com (PAN_ONLY) and/or a device token on an Android device authenticated with a 3-D Secure cryptogram (CRYPTOGRAM_3DS).
Please make sure that you define CRYPTOGRAM_3DS only if your acquirer is supporting this functionality. Please contact Computop Helpdesk to verify this point if needed.
const allowedCardAuthMethods = ["PAN_ONLY", "CRYPTOGRAM_3DS"];
If you are operating in EEA region, please define CRYPTOGRAM_3DS only, as these payments are already Strong Customer Authenticated in Google Pay wallet and therefore compliant with PSD2 SCA regulation.
Note: If you receive Soft Decline in Response, you need to restart the payment with 3-D Secure authentication.
d. In response from Google Pay API, you should receive Token similar to this:
{
"signature": "MEQCIC4z/QHSrzekRkkuk3vGYxBTBdNgEQl5XFHx0Wk5fFLIUAiB3+q227havAJdagfGZaMXbefhatdJE7Df2qrIoKDv1Og==",
"protocolVersion": "ECv1",
"signedMessage": "{\"encryptedMessage\":\"bOYRmExGeCsBrFqESt7kd9O1FN+vQZf2KG0UNYC8jNA+VVf9nQeK7lDvU8k37cH+LOziJQkHNL2OxDHIk6GoRV1BrXprwBnAJR0O2VnCUH8lsqq0ELwemeqW364Ir8cU/hDFzWNp+38H25JVDAMExZBKodMMTzUXXgyO+s5jOyAl8jUhnAw3fTRPkefuYsE8NFK5tvcs4L29h87Zo7ot0/8XrUhXt9b/Fld1LEthkuPSN+K1eEFP7bseB6jjRdHnwYAdqiE3iOmh71pcDmNIyrlWRj74UJaszeerZW7DoZNx11oN7fouq/8fe1vklsr/e+y/RSG2nQMWg5yR/fMTfqCyabTDhJMvMM1Zhe91+dQ0/xi/zKRgsIhiongJUjYtoSNIjUHnMLRuVTKdjX50CCI1QOiBtr9h0bOLePhxw9cLYeU1KwCfYJyt28DBKCvaWFSbCl+dzNcZ9B83kv\",\"ephemeralPublicKey\":\"BFUju73/IT/KqnB/nc0W3BaL3BXFybrbYaPiMCKXIcg78PbslwV7MRUq3SpWEDEJT6pakLCvf34412HbDGCpsa4\\u003d\",\"tag\":\"xIuCUWB2U6yWEfidsJpQaa+leU/kqS522JLOnrnk42g\\u003d\"}"
}
You need to Base64 encode the whole token string and include it in Paygate parameter TokenExt.
Process flow chart
Google Pay process flow
Paygate interface
Format Description a alphabetical as alphabetical with special characters n numeric an alphanumeric ans alphanumeric with special characters ns numeric with special characters bool boolean expression (true or false) 3 fixed length with 3 digits/characters ..3 variable length with maximum 3 digits/characters enum enumeration of allowed values dttm ISODateTime (YYYY-MM-DDThh:mm:ss) Abbreviation Description CND condition M mandatory O optional C conditional Notice: Please note that the names of parameters can be returned in upper or lower case.Definitions
Data formats
Abbreviations
Comment If a parameter is mandatory, then it must be present If a parameter is optional, then it can be present, but it is not required If a parameter is conditional, then there is a conditional rule which specifies whether it is mandatory or optional
Calling the interface
Two transactions are created when making a credit card payment via Google Pay. In the Google Pay transaction the required credit card data are determined first and the actual credit card transaction is then carried out automatically. This takes place via a server-to-server connection and supports all usual credit card transaction options. The difference here, however, is that you don't transmit the credit card information, which you don't know. Instead, you transmit the Token generated by Google Pay, which contains the required credit card data in encrypted form.
In order to make a credit card payment with Google Pay, please use the following URL:
https://www.computop-paygate.com/googlepay.aspx |
Notice: For security reasons, Computop Paygate rejects all payment requests with formatting errors. Therefore, please use the correct data type for each parameter. The following table describes the encrypted payment request parameters:
In addition you can submit any parameters that are applicable or required for a credit card payment (without credit card data). More information about this you can find within Card processing.
Parameters for Google Pay
The following table describes the result parameters with which the Computop Paygate responds to your system
pls. be prepared to receive additional parameters at any time and do not check the order of parameters the key (e.g. MerchantId, RefNr) should not be checked case-sentive
Result parameters for Google Pay
Capture / Credit / Reversal
Captures, credits and reversals do not refer to the Google Pay transaction but directly to the credit card transaction. More information about this you can find within Card processing.
Batch processing via the interface
Captures, credits and reversals via batch do not refer to the Google Pay transaction but directly to the credit card transaction. More information about this you can find within the document Card processing.