Secure Inputs SDK for Tokenization

Note: The secure inputs SDK for tokenization is a more customizable checkout solution. For a simpler, drop-in solution, use the Checkout SDK.

Highnote's secure inputs SDK can be used to tokenize payment method details so you can process payments in your application or website. This prevents PCI-scoped data from flowing through your servers or being accessible to scripts running on your page.

This guide provides an overview of requirements, installation steps, and usage guidelines for the secure inputs SDK.

1. A Highnote account
2. A server-side integration using an API key
3. Payment card ID

You can install the secure inputs SDK using Javascript package managers or CDN. For more installation information, see the SDK Installation guide.

To render secure input fields in your UI, you must configure elements to hold each field. This involves the following steps:

1. Prepare your HTML.
2. Fetch a client token.
3. Initialize secure inputs.

To use the secure inputs SDK, you must provide elements for the payment details fields.

The following fields are supported for the secure inputs SDK for tokenization:

• cardNumber
• expirationDate or expirationMonth and expirationYear
• securityCode

To obtain a client token from your server for the secure inputs SDK, use the generatePaymentMethodTokenizationClientToken mutation.

Refer to the following guidelines when generating a payment method tokenization client token:

• The client token is only valid for 10 minutes but can be used multiple times.
• Once a token expires, you must generate a new one.

Use the following mutation to generate a payment method tokenization client token:

The secure inputs library works by injecting an iframe into the payment element to render the appropriate data. You can style the content inside each iframe by passing any combination of styling options.

You can initialize the card viewer by using a renderFieldsForTokenization function. This returns a Promise that contains a reference to the secureInputs instance. This is useful for lifecycle management and interactions such as field submission.

The following example shows how to initialize the secure inputs SDK for tokenization:

Note: The secure inputs SDK doesn’t render error messages or update your UI inside iframes when errors occur. You must introspect and handle errors accordingly.

You can pass an onError handler to the renderFieldsForTokenization call. This callback will be invoked whenever an error is raised from the integration.

The following error types are supported for the secure inputs SDK for tokenization:

The following code samples provides examples of secure inputs errors:

The following styling options are available for use in elements for your secure inputs fields:

Highnote injects card viewer iframes with the following defaults. Your CSS styling can override each of these:

• border: none
• width: 300px (browser default)
• height: 150px (browser default)

The document and body inside the frame will have transparent backgrounds and default to margin: 0, padding: 0

The secure inputs SDK only supports system fonts.

The layout of payment card fields in the card viewer is customizable. Highnote injects iframes into the provided container elements, which will inherit the width of the container. You can customize the width and height of the container to accommodate your UI as needed.

The following code sample provides an example of custom layout styling:

By default, the card viewer library will make requests against the test environment. When you are ready to switch to the live environment, set the environment configuration option using the following function call:

The secure inputs SDK's lifecycle consists of unmounting fields.

If you need to unmount payment card fields, use the unmount method on the returned reference. This is useful when you need to “restart” the integration, or navigate to a new view client-side. Using this will ensure the cleanup of any DOM and event handlers.

The following code sample provides an example function to unmount fields:

If your application enforces a content security policy, you must set the frame-src header to allow iframes from the Highnote domain: