📄️ Getting Started
At SumUp accepting online payments is possible through a number of different approaches, to cater every merchants' use case. With the SumUp APIs you are able to build a complete and custom payments flow. Your app can communicate with SumUp via HTTP requests, all defined in our API Reference.
📄️ Register application
In order to integrate an external application with SumUp's ecosystem, you have to register an OAuth application and generate the client credentials which are used to make OAuth-authenticated requests on behalf of your application. You can see more on OAuth2 authorization flows, which explain how to request an access token that is used to obtain permission to protected resources within SumUp's API.
SumUp supports two kinds of authorization. One is via API keys allowing you to authorize on your behalf and access the SumUp API, as if you were logged in.
📄️ Response Handling
Once an API call is submitted to SumUp, you will receive a response informing you if your request has been successful or not. In most cases the HTTP codes are accompanied by a response body in JSON format.
Webhooks are a convenient approach to notify an application about relevant events that have taken place within another application.