Setting up a custom REST backend with Supersonic Data

Using a custom REST backend requires a bit more setup compared to the other Data Providers. As an example, we'll use JSONPlaceholder, which provides a free REST service for development purposes.

A list of posts can be fetched by making a HTTP GET request to the URL, and that an post is accessed by adding the identifier of the post to the URL, e.g. with We need to configure these actions in order for Supersonic Data to access the API.


After initializing data for your app, select the Custom REST API from the list of available providers.

All the URLs of the API are prefixed with the base URL: This is the Base URL we should set up when defining the custom data provider.

In the Config dialog we could also define the authentication scheme and add some default request headers for the requests Supersonic Data makes.

Since authentication and header definitions are not needed for JSONPlaceholder, we can skip those.

Adding Resources

Next step is to add resources for the provider. The dialog asks for the resource name and URL path. Enter those:

Note that for the path you should specify only the part of the path that is shared by all the resource operations, i.e. just posts, not posts/1. After creating the resource, the data will be pulled from JSONPlaceholder and the resource model will be automatically configured.

Not all resource providers will be automatically configured. For more specialized use cases, you have the option to provide additional configuration via the "Customize actions" button.

Customizing actions for a resource

One of the most common stumbling blocks for automatic data configuration is the scenario where the response is an object that has some metadata as well as an array of result objects. For Supersonic Data to access the actual results, you would need to index the response with the root key. For example, let's say the data returned by JSONPlaceholder looked something like the following:

  page: 1,
  pages: 15,
  posts: [
      userId: 1,
      id: 1,
      title: "sunt aut facere repellat provident occaecati excepturi optio reprehenderit",
      body: "quia et suscipit suscipit recusandae consequuntur expedita et cum reprehenderit molestiae ut ut quas totam nostrum rerum est autem sunt rem eveniet architecto"
      userId: 1,
      id: 2,
      title: "qui est esse",
      body: "est rerum tempore vitae sequi sint nihil reprehenderit dolor beatae ea dolores neque fugiat blanditiis voluptate porro vel nihil molestiae ut reiciendis qui aperiam non debitis possimus qui neque nisi nulla"

In this scenario, you would need to set the root key posts for the resource to be properly loaded.

Going forward

The custom data is now all set up. JSONPlaceholder supports all HTTP verbs, so feel free to experiment with different Supersonic Data requests. Now you can also browse the data in API on the Data Browser tab, or scaffold a CRUD application using your resource from the Generate Scaffolds tab.

Refer to the Setting Up AppGyver Database and Accessing Data from Device guides for more information on Supersonic Data.