This topic provides an integration guide and an example of the wireframe document you need to complete as part of your submission to list your application on the Square App Marketplace.
A wireframe document requests the following information about your application:
- A high-level summary of what your application does and what it will do with a seller's Square account data.
- A diagram (such as a UML, a swimlane, or another robust diagram) for each way a seller can access their Square account information through your application.
- A UML diagram of your OAuth flow that shows you've properly implemented OAuth and you're following the best practices for handling sensitive Square user data.
- API-specific questions in Partner Team-provided questionnaires.
The summary can be a short paragraph that describes the intended market for your application and how the application should be used. An application called Dogfood POS might be summarized as follows:
Dogfood POS is a point of sale management system for restaurants that serves canines of all kinds. We leverage Square's Terminal API to help restaurants take Card Present Swipe, Chip and PIN, and Contactless transactions. The application uses the Devices API to create device codes and the Terminal API to create and manage checkout sessions on the Square Terminal.
The following diagram is an example of how you might create a UML diagram for the Square API call flow in your application. You can provide cURL examples for the Square API request and a JSON object that represents the response that you will parse. If you're handling webhook events resulting from the call flow, be sure to note the events that you handle and the application component that is handling them.
In this wireframe example, Dogfood POS has a working business logic and data access layer. The UI layer is not complete so the developer mocked it using balsamiq. You can also capture application screens if your application prototype has a running UI. High-fidelity or low-fidelity screens are fine in your wireframe—Square needs to understand how your application uses the Square APIs and platform to provide the best feedback possible.
The Partner team uses the UML diagrams to verify the sequence of API calls that you make, how you're forming API requests, and whether you're using webhooks to make your application reactive to asynchronous events from Square.
This diagram captures only one of the Square API call flows that Dogfood POS makes. A complete wireframe includes the OAuth call flow and any other Terminal API calls as documented in the Square Terminal API Overview. Be sure to diagram all Square API calls and webhook events that your application uses.
The App Marketplace requirements questionnaire gives you the opportunity to learn about what is required for your application to be approved for publication in the App Marketplace. Each Square API has its own set of requirements and a questionnaire that can be downloaded. You can answer all relevant questions and download the questionnaires with your answers for distribution to your development team. Use the documents to track your progress towards meeting all requirements.