grocy/middleware/AuthMiddleware.php

<?php

namespace Grocy\Middleware;

use Psr\Http\Message\ResponseFactoryInterface;
use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;
use Psr\Http\Server\RequestHandlerInterface as RequestHandler;
use Slim\Routing\RouteContext;

use Grocy\Services\SessionService;

abstract class AuthMiddleware extends BaseMiddleware
{
    public function __construct(\DI\Container $container, ResponseFactoryInterface $responseFactory)
    {
        parent::__construct($container);
        $this->ResponseFactory = $responseFactory;
    }

    protected $ResponseFactory;

    public function __invoke(Request $request, RequestHandler $handler): Response
    {
        $routeContext = RouteContext::fromRequest($request);
        $route = $routeContext->getRoute();
        $routeName = $route->getName();
        $isApiRoute = string_starts_with($request->getUri()->getPath(), '/api/');

        if ($routeName === 'root')
        {
            return $handler->handle($request);
        }
        else if ($routeName === 'login')
        {
            define('GROCY_AUTHENTICATED', false);
            return $handler->handle($request);
        }
        if (GROCY_MODE === 'dev' || GROCY_MODE === 'demo' || GROCY_MODE === 'prerelease' || GROCY_IS_EMBEDDED_INSTALL || GROCY_DISABLE_AUTH)
        {
            $sessionService = SessionService::getInstance();
            $user = $sessionService->GetDefaultUser();

            define('GROCY_AUTHENTICATED', true);
            define('GROCY_USER_USERNAME', $user->username);

            return $handler->handle($request);
        }
        else
        {
            $user = $this->authenticate($request);

            if ($user === null)
            {
                define('GROCY_AUTHENTICATED', false);

                $response = $this->ResponseFactory->createResponse();
                if ($isApiRoute)
                {
                    return $response->withStatus(401);
                }
                else
                {
                    return $response->withHeader('Location', $this->AppContainer->get('UrlManager')->ConstructUrl('/login'));
                }
            }
            else
            {
                define('GROCY_AUTHENTICATED', true);
                define('GROCY_USER_ID', $user->id);
                define('GROCY_USER_USERNAME', $user->username);

                return $response = $handler->handle($request);
            }
        }
    }

    /**
     * @param Request $request
     * @return mixed|null the user row or null if the request is not authenticated
     * @throws \Exception Throws an \Exception if config is invalid.
     */
    protected abstract function authenticate(Request $request);
}