Overview

Google Pay™ is a secure digital wallet that simplifies checkout. Learn how it works with Curbstone and what merchants must comply with.

Google Pay™ is a secure digital wallet that simplifies checkout by eliminating the need to manually enter payment information. Google securely stores all payment credentials, enabling seamless transactions across any device, browser, or operating system.

Curbstone is the payment processor for Google Pay. Your website requests payment details from Google, and Google returns an encrypted payment token that is addressed to the Curbstone gateway.

Merchant requirements#

Merchants integrating Google Pay must comply with the guidelines and regulations published by Google, including the Google Pay API terms of service for sellers.

Web integration

Integrate Google Pay on your website and configure the Curbstone gateway parameters.

For website integration with the Google Pay™ method, follow these steps.

Google resources#

Use Google's documentation for the client-side integration, and complete these items before launch.

Production accessRequest production access for your integration.Integration checklistVerify your integration against Google's checklist.API documentationThe Google Pay API for web reference.Brand guidelinesDisplay the Google Pay button and brand correctly.

Gateway configuration#

The gateway parameter in the script must have the constant value curbstone, as shown in this example.

tokenizationSpecification

const tokenizationSpecification = {
  type: "PAYMENT_GATEWAY",
  parameters: {
    gateway: "curbstone",
    gatewayMerchantId: "CurbstoneMerchantId"
  }
}

tokenizationSpecification

const tokenizationSpecification: google.payments.api.PaymentMethodTokenizationSpecification = {
  type: "PAYMENT_GATEWAY",
  parameters: {
    gateway: "curbstone",
    gatewayMerchantId: "CurbstoneMerchantId"
  }
}

tokenizationSpecification

<?php
$tokenizationSpecification = [
    'type' => 'PAYMENT_GATEWAY',
    'parameters' => [
        'gateway' => 'curbstone',
        'gatewayMerchantId' => 'CurbstoneMerchantId',
    ],
];
$flags = JSON_HEX_TAG | JSON_HEX_AMP | JSON_HEX_APOS | JSON_HEX_QUOT;
?>
<script>
  const tokenizationSpecification = <?= json_encode($tokenizationSpecification, $flags) ?>;
</script>

Parameters#

Parameter	Value	Description
`type`	`PAYMENT_GATEWAY`	Tokenization type used when a payment gateway processes the payment.
`gateway`	`curbstone`	Constant value. Do not change it.
`gatewayMerchantId`	Your Curbstone Merchant ID	The unique Merchant ID provided by Curbstone.

Networks and methods

Card networks and authentication methods that Curbstone supports for Google Pay.

As the payment processor for Google Pay™, Curbstone supports AMEX, DISCOVER, INTERAC, JCB, MASTERCARD, and VISA.

Supported card networks#

Network	Value
American Express	`AMEX`
Discover	`DISCOVER`
Interac	`INTERAC`
JCB	`JCB`
Mastercard	`MASTERCARD`
Visa	`VISA`

Authentication methods#

Method	Description
`PAN_ONLY`	Cards stored in the customer's Google Account. Returns the card number (PAN) and expiration date.
`CRYPTOGRAM_3DS`	Device-tokenized cards. Returns a device token with a 3-D Secure cryptogram.

Script configuration#

Configure the Google Pay script using the following parameter settings.

Card parameters

const allowedCardNetworks = ["AMEX", "DISCOVER", "INTERAC", "JCB", "MASTERCARD", "VISA"]
const allowedCardAuthMethods = ["PAN_ONLY", "CRYPTOGRAM_3DS"]

Card parameters

const allowedCardNetworks: google.payments.api.CardNetwork[] = ["AMEX", "DISCOVER", "INTERAC", "JCB", "MASTERCARD", "VISA"]
const allowedCardAuthMethods: google.payments.api.CardAuthMethod[] = ["PAN_ONLY", "CRYPTOGRAM_3DS"]

Card parameters

<?php
$allowedCardNetworks = ['AMEX', 'DISCOVER', 'INTERAC', 'JCB', 'MASTERCARD', 'VISA'];
$allowedCardAuthMethods = ['PAN_ONLY', 'CRYPTOGRAM_3DS'];
$flags = JSON_HEX_TAG | JSON_HEX_AMP | JSON_HEX_APOS | JSON_HEX_QUOT;
?>
<script>
  const allowedCardNetworks = <?= json_encode($allowedCardNetworks, $flags) ?>;
  const allowedCardAuthMethods = <?= json_encode($allowedCardAuthMethods, $flags) ?>;
</script>

Payment token

Where Google returns the encrypted payment token and what the payload looks like.

Upon successful authentication, Google returns the PaymentData payload. The encrypted Google Pay token is located in the paymentMethodData.tokenizationData.token field.

Read the token#

The token is a JSON string at paymentMethodData.tokenizationData.token. In the browser, read it from the PaymentData object that Google returns. If your page posts PaymentData to your server as JSON, you can read the same field there.

Read the token

const token = paymentData.paymentMethodData.tokenizationData.token

Read the token

const token: string = paymentData.paymentMethodData.tokenizationData.token

Read the token

<?php
$paymentData = json_decode(file_get_contents('php://input'), true);
$token = $paymentData['paymentMethodData']['tokenizationData']['token'];

Sample Google Pay token#

paymentMethodData.tokenizationData.token

{
  "signature": "MEUCIQDY3wBQyHB4sZcktRoJXKxm+OLcjHzCvdDeGn23oX0kkwIgKznRFZZL+sDMv1b5cuD+YurXMZraYBsr9hbravVY5Ro\u003d",
  "protocolVersion": "ECv1",
  "signedMessage": "{\"encryptedMessage\":\"cI87tLqzqTGyCFnMMCVWcTHw3xhYIK+CEnuQ74K+nlLpCgOlfpScib9jds4sxDtN6CunCqCSMfd/3yHeeRy6aCx1yyqcT4ey6NueeBznprJpkmVVgI1JHWLQt4hzAXMUAcYASYLOabKP9fUZvHkOBDytD531jpzNXa+Spc/zrpGzFKx2C4VU9sC95q9i+ey+kr7ZMNVCOFJPWXu7lKZ105IOOqozJ6/70MKmxP3jM89eeq+/19QnyHjQLXfnQPvQjiUJKGCcRKDLlrb3XoY5ZUUzGfN5eZCLzCVg0hWEbwU+6J7KWYJyW+Wr1r8bagN9zWsrMKhDpsQbHfyzb+yBzFUoxeUgL4a7FeVvEllIcHtqsvTCf6FENV20aF5VLDv5qzUkV+PzTAIbFEuabA0God9UbVCVVv7nM8QFzvRPhzYYFVFTn4JHvL2qZ4pAR9lE+w\\u003d\\u003d\",\"ephemeralPublicKey\":\"BPHLC4sBHpenY1M0ixmiDMuWJTaTJOqggRUwtgBJMcBp28VsxHD7zPI7985x4F5EjMP5y8j/cuUzbe/cGPjOKGk\\u003d\",\"tag\":\"RaXrPOUuc5iw3oxDa0C2MOjaKxgxIRQvwOspmtFV0zU\\u003d\"}"
}

Token fields#

Field	Description
`signature`	Signature that Google generates over the signed message.
`protocolVersion`	Version of the token protocol. The sample above uses `ECv1`.
`signedMessage`	A JSON string containing the encrypted payment data: `encryptedMessage`, `ephemeralPublicKey`, and `tag`.

Testing (sandbox)

Use the TEST environment while you build and verify your Google Pay integration.

During integration and testing, explicitly set the environment property to 'TEST' when initializing the Google Pay client.

Initialize the client (TEST)

var paymentsClient = new google.payments.api.PaymentsClient({
  environment: 'TEST'
})

Initialize the client (TEST)

const paymentsClient = new google.payments.api.PaymentsClient({
  environment: 'TEST'
})

Initialize the client (TEST)

<?php $environment = 'TEST'; ?>
<script>
  var paymentsClient = new google.payments.api.PaymentsClient({
    environment: <?= json_encode($environment) ?>
  })
</script>

Go live

Switch to the production environment and complete the launch checklist before processing live Google Pay transactions.

When you are ready to process live transactions, switch the environment property to 'PRODUCTION'.

Environment#

Testing#

TEST environment

var paymentsClient = new google.payments.api.PaymentsClient({
  environment: 'TEST'
})

TEST environment

const paymentsClient = new google.payments.api.PaymentsClient({
  environment: 'TEST'
})

TEST environment

<?php $environment = 'TEST'; ?>
<script>
  var paymentsClient = new google.payments.api.PaymentsClient({
    environment: <?= json_encode($environment) ?>
  })
</script>

Production#

Production environment

var paymentsClient = new google.payments.api.PaymentsClient({
  environment: 'PROD'
})

Production environment

const paymentsClient = new google.payments.api.PaymentsClient({
  environment: 'PROD'
})

Production environment

<?php $environment = 'PROD'; ?>
<script>
  var paymentsClient = new google.payments.api.PaymentsClient({
    environment: <?= json_encode($environment) ?>
  })
</script>

Launch checklist#

Work through these items before you process live transactions. Your progress is saved in this browser.

0 of 9 complete

Accept the Google Pay seller termsReview the Google Pay API Terms of Service for sellers.
Follow Google Pay brand guidelinesMake sure the Google Pay button and branding meet Google's requirements.
Set the gateway to curbstoneThe gateway parameter must have the constant value curbstone.
Use your Curbstone Merchant IDSet gatewayMerchantId to the unique Merchant ID provided by Curbstone.
Configure supported networks and methodsAMEX, DISCOVER, INTERAC, JCB, MASTERCARD, VISA with PAN_ONLY and CRYPTOGRAM_3DS.
Test in the TEST environmentVerify a full checkout flow with environment set to TEST.
Complete Google's integration checklistConfirm each item on Google's integration checklist.
Request production access from GoogleSubmit your integration through Google's publish process.
Switch the environment for live transactionsUpdate the environment property as shown above.

Request production accessGoogle's guide to publishing your integration.Google integration checklistThe official checklist for web integrations.

Error codes

Standard errors returned by Google Pay and where to find troubleshooting guidance.

The list of standard errors returned by Google Pay is maintained by Google. See the Google Pay API troubleshooting guide.

Support

Contact Curbstone for help with your Google Pay integration.

Open a ticket#

Open a ticket at curb911.com for integration questions, Merchant ID requests, and processing issues.

Urgent issues#

For urgent issues, call our 24/7 urgent support line at 888-844-8533.