chadicus / slim-oauth2-middleware

src/Authorization.php

<?php
namespace Chadicus\Slim\OAuth2\Middleware;

use ArrayAccess;
use Chadicus\Slim\OAuth2\Http\RequestBridge;
use Chadicus\Slim\OAuth2\Http\ResponseBridge;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface;
use Interop\Container\ContainerInterface;
use OAuth2;

/**
 * Slim Middleware to handle OAuth2 Authorization.
 */
class Authorization implements MiddlewareInterface
{
    /**
     * OAuth2 Server
     *
     * @var OAuth2\Server
     */
    private $server;

    /**
     * Array of scopes required for authorization.
     *
     * @var array
     */
    private $scopes;

    /**
     * Container for token.
     *
     * @var ArrayAccess|ContainerInterface
     */
    private $container;

    /**
     * Create a new instance of the Authroization middleware.
     *
     * @param OAuth2\Server                  $server    The configured OAuth2 server.
     * @param ArrayAccess|ContainerInterface $container A container object in which to store the token from the
     *                                                  request.
     * @param array                          $scopes    Scopes required for authorization. $scopes can be given as an
     *                                                  array of arrays. OR logic will use with each grouping.
     *                                                  Example:
     *                                                  Given ['superUser', ['basicUser', 'aPermission']], the request
     *                                                  will be verified if the request token has 'superUser' scope
     *                                                  OR 'basicUser' and 'aPermission' as its scope.
     *
     * @throws \InvalidArgumentException Thrown if $container is not an instance of ArrayAccess or ContainerInterface.
     */
    public function __construct(OAuth2\Server $server, $container, array $scopes = [])
    {
        $this->server = $server;
        if (!is_a($container, '\\ArrayAccess') && !is_a($container, '\\Interop\\Container\\ContainerInterface')) {
            throw new \InvalidArgumentException(
                '$container does not implement \\ArrayAccess or \\Interop\\Container\\ContainerInterface'
            );
        }

        $this->container = $container;
        $this->scopes = $this->formatScopes($scopes);
    }

    /**
     * Execute this middleware as a function.
     *
     * @param  ServerRequestInterface $request  The PSR7 request.
     * @param  ResponseInterface      $response The PSR7 response.
     * @param  callable               $next     The Next middleware.
     *
     * @return ResponseInterface
     */
    public function __invoke(ServerRequestInterface $request, ResponseInterface $response, callable $next)
    {
        $handler = new class implements RequestHandlerInterface

This class is not in CamelCase format.

        {
            public $next;
            public $response;

            /**
             * Handle the request and return a response.
             *
             * @param ServerRequestInterface $request The request to handle.
             *
             * @return ResponseInterface
             */
            public function handle(ServerRequestInterface $request): ResponseInterface
            {
                return call_user_func_array($this->next, [$request, $this->response]);
            }
        };

        $handler->next = $next;
        $handler->response = $response;

        return $this->process($request, $handler);
    }

    /**
     * Execute this middleware.
     *
     * @param ServerRequestInterface  $request The PSR-7 request.
     * @param RequestHandlerInterface $handler The PSR-15 request handler.
     *
     * @return ResponseInterface
     */
    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler) : ResponseInterface
    {
        $oauth2Request = RequestBridge::toOAuth2($request);
        foreach ($this->scopes as $scope) {
            if ($this->server->verifyResourceRequest($oauth2Request, null, $scope)) {
                $this->setToken($this->server->getResourceController()->getToken());
                return $handler->handle($request);
            }
        }

        $response = ResponseBridge::fromOauth2($this->server->getResponse());

        if ($response->hasHeader('Content-Type')) {
            return $response;
        }

        return $response->withHeader('Content-Type', 'application/json');
    }

    /**
     * Helper method to set the token value in the container instance.
     *
     * @param array $token The token from the incoming request.
     *
     * @return void
     */
    private function setToken(array $token)
    {
        if (is_a($this->container, '\\ArrayAccess')) {
            $this->container['token'] = $token;
            return;
        }

        $this->container->set('token', $token);
    }

    /**
     * Returns a callable function to be used as a authorization middleware with a specified scope.
     *
     * @param array $scopes Scopes require for authorization.
     *
     * @return Authorization
     */
    public function withRequiredScope(array $scopes)
    {
        $clone = clone $this;
        $clone->scopes = $clone->formatScopes($scopes);
        return $clone;
    }

    /**
     * Helper method to ensure given scopes are formatted properly.
     *
     * @param array $scopes Scopes required for authorization.
     *
     * @return array The formatted scopes array.
     */
    private function formatScopes(array $scopes)
    {
        if (empty($scopes)) {
            return [null]; //use at least 1 null scope
        }

        array_walk(
            $scopes,
            function (&$scope) {
                if (is_array($scope)) {
                    $scope = implode(' ', $scope);
                }
            }
        );

        return $scopes;
    }
}