Partner Quick Start Payment Initiation

Quick Start - Let's make an Open Banking payment!

Overview

This section gives partners an overview of the API calls required for the three integration models:

REDIRECT
SELF-HOSTED
CHECKOUT [to be phased out]

Tip: The CHECKOUT integration can be problematic in the mobile flow on some devices. For that reason we recommend that clients who want to use the Nuapay User Interface select the REDIRECT option. For users who currently use CHECKOUT, your integration will continue to be supported but we recommend that you consider moving to the REDIRECT flow. Please contact your Account Manager if you require assistance with this.

See Implementation Options for more on these options.

Depending on the setup that best suits your business needs, the API calls that you need to make and how you process the responses vary.

Postman Collection

We highly recommend that you use Postman to test our Payment Initiation APIs on the Sandbox environment. Download it for free from www.postman.com/downloads.

Tip: Unlike the Swagger specification, the Postman Collection we’ve created allows you to work with the APIs directly in our Sandbox environment. While our Swagger file is a formal definition of our Payment Initiation service, which you can use to generate client libraries, the Postman Collection logically groups the services together so that you can see the business logic of why (and when) to call the various Payment Initiation endpoints.

You will need to download:

A Collection .JSON file.
An Environment .JSON file.

Download the files from Github here: Postman Collections on Github

If you are new to Postman and are unsure how to import the collection, please see the README.

Once you have downloaded the Collection and the Environment files:

Open Postman.
Import the collection files.
Specify your API Key.

Tip: If you don’t already have one, contact our Support Team to request an API Key: api.support@nuapay.com.

Redirect Mode

Note: CHECKOUT and REDIRECT is only available for merchants who want to process GBP payments; if you want to process EUR transactions then use the SELF-HOSTED integration.

As a partner, you will need to interact with the Nuapay Open Banking services on behalf of your merchants. In this example we will assume that you want to set up a payment for Merchant X but do not have the merchant identifier and need to query the GET /organisations service to retrieve it as a first step.

Call the following services in this order

GET	Organisations	(Optional) Use this service to retrieve the list of organisations/merchants under you as the Partner entity. Use your Partner-level API Key and store the required merchant identifier.
POST	Access Token	Use this service to retrieve an OAuth token for the required merchant. Pass your API Key and merchantId with scope = `openbanking_pisp`.
POST	Create Payment	Call this service with the merchant access token. The `integrationType` must be set to REDIRECT and the `merchantPostAuthUrl` must be provided. The Create Payment service generates an Open Banking payment object, returning a unique `userInterfacePaymentId` with the payment object having an (initial) status of `PENDING`. The URI must be passed to the PSU; once the user click the link the Bank Selection screen is launched in a new browser window/tab.
-	-	The PSU selects a bank and is redirected to authenticate and approve the payment on that ASPSP’s online banking portal.
GET	Retrieve Payment Status	Retrieve the status of the payment.

For more details on this see the Partner-level Redirect Setup.

Self-Hosted

Call the following services in this order:

GET	Organisations	(Optional) Use this service to retrieve the list or organisations/merchants under you as the Partner entity. Use your Partner-level API Key and store the required merchant identifier.
POST	Access Token	Use this service to retrieve an OAuth token for the required merchant. Pass your API Key and merchantId with scope = `openbanking_pisp`.
GET	Retrieve Banks	Use this service to give your PSU a list of banks from which to choose
-	-	The PSU selects a bank (also referred to as the ASPSP).
POST	Create Payment	Once the user selects an ASPSP, pass its `bankId` in the payment request.
-	-	The PSU is redirected to authenticate and approve the payment on that ASPSP’s online banking portal. Once the user approves or declines the payment he/she is redirected to the `merchantPostAuthUrl` (as referenced in the Create Payment call).
GET	Retrieve Payment Status	Retrieve the status of the payment.

For more details on this see the Partner-Level Self-Hosted Setup

Self-Hosted Callback

Tip: The Self-Hosted-Callback integration is only available for merchant integrations. For more details on this, see the [Merchant section[(ob_selfcallbackmerch.html)].

Checkout Mode

Tip: The CHECKOUT integration can be problematic in the mobile flow on some devices. If you want to use the Nuapay UI, we recommend that you use the REDIRECT integration to avoid any issues.

Note: CHECKOUT and REDIRECT are only available for merchants who want to process GBP payments; if you want to process EUR transactions then use the SELF-HOSTED integration.

Call the following services in this order:

GET	Organisations	(Optional) Use this service to retrieve the list of organisations/merchants under you as the Partner entity. Use your Partner-level API Key and store the required merchant identifier.
POST	Access Token	Use this service to retrieve an OAuth token for the required merchant. Pass your API Key and merchantId with scope = `openbanking_pisp`.
POST	Create Payment	Call this service with the merchant access token; the Create Payment service generates an Open Banking payment object, returning a unique `userInterfacePaymentId` with an (initial) status of `PENDING`. Apply the Nuapay-provided JS and CSS on your page to render the Bank Selection screen for your merchant’s payers.
-	-	The PSU selects a bank (also referred to as the ASPSP) and is redirected to authenticate and approve the payment on that ASPSP’s online banking portal.
GET	Retrieve Payment Status	Retrieve the status of the payment.

For more details on this see the Partner-level Checkout Setup.