Processing a card payment (other languages)
SqPaymentForm generates a card nonce and you submit
it to your server, you finish processing the payment by sending a request
endpoint with the details of the transaction.
Square provides client libraries in several languages for communicating with eCommerce API endpoints.
Learn about OAuth
Your personal access token gives you full access to your own business' data. If you are developing an application for other businesses to use as well, you use the OAuth API to generate access tokens for those businesses.
Important: In order for your app to process
payments on behalf of another merchant, the merchant must authorize your
application with the
PAYMENTS_WRITE OAuth permission.