Here is the code that I used and site url https://1usda.technology/rest.php
<?php
use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;
use Slim\Factory\AppFactory;
require __DIR__ . '/../vendor/autoload.php';
$app = AppFactory::create();
$app->get('/', function (Request $request, Response $response, $args) {
$response->getBody()->write("Hello world!");
return $response;
});
$app->run()
?>