RESTful API

Representational State Transfer (REST) is a software architectural style that defines a set of constraints to be used for creating Web services. Web services that conform to the REST architectural style, called RESTful Web services (RWS), provide interoperability between computer systems on the Internet.

from wikipedia

SmartAdmin for PHP has built-in REST API server that you can already use out of the box. Provided that you enabled mod_rewrite in the installation, you can configure your REST API server in minutes!

To play around with this feature, head over to the API Tester page.

Routes

The API routes are basically the endpoints of your API. These routes are configured/defined under public/api folder. To learn more on how to design your API better, follow this tutorial about REST apis.
You can configure these routes in the api/includes/_routes.php file. To learn more about adding routes, visit Slim's Routing documentation.

Example route request:

GET https://smartadmin.lodev09.com/api/v1/users/:id

Response:

Status: 200 OK
{
    "id": 1,
    "username": "lodev09",
    "name": "Jovanni",
    "email": "lodev09@gmail.com",
    "created_at": "2019-07-02T19:34:22Z"
}

Authenticated Routes

Those end-points (resource) that you want to be secured, you would most likely require an authorized user to access it.
The built-in REST API server comes with the Authentication routine which is handled by the \API\Middlewares\AuthMiddleware middleware. The main function of this middleware is to basically check if the request contains Authorization header so the app knows that the request is authorized. It should look something like this:

Authorization Bearer YOUR_TOKEN

To retrieve a token, you will call the POST /authenticate end-point passing the user's username and password.

POST https://smartadmin.lodev09.com/api/v1/authenticate
{"username":"lodev09","password":"smartadmin2021"}

Response:

Status: 200 OK
{
    "id": 250,
    "token": "c111b3ef7a0054126c126035fbbccda1260a8fa605570a5c28369fcbd24b84e6",
    "created_at": "2021-02-08T17:15:16+0000"
}

Middlewares

SmartAdmin PHP includes various middlewares to handle each request. For example, the \API\AuthMiddleware where it validates the user credentials passed through the Authentication header -- basically checking if the request is authenticated or not.

Here are the included middlewares:

Credits

SmartAdmin PHP uses slimphp/Slim package to host the API server. Refer to their documentation on how to create your own routes and customize your REST API server.