Respect\Validation custom Rule with PDO?

Question

I am learning Slim Framework v4 and decided to use Respect\Validation to validate inputted data and have hit a snag where I do not know how to inject the PDO into my custom rule I created.

The idea is to validate some inputs against the database if the provided data exist (or in another instances, if it was inputted correctly). In this specific case, I am tying to validate user's credentials for log in. My idea is this:

AuthController.php:

    v::with('app\\Validators\\');
    $userValidation = v::notBlank()->email()->length(null, 255)->EmailExists()->setName('email');

EmailExists() is my custom rule.

EmailExists.php:

namespace app\Validators;

use PDO;
use Respect\Validation\Rules\AbstractRule;

class EmailExists extends AbstractRule
{
    protected $pdo;

    public function __construct(PDO $pdo)
    {
        $this->pdo = $pdo;
    }

    public function validate($input, $id = null)
    {
    // a PDO query that checks if the email exists in database
    }
}

But I get an error of Too few arguments to function app\Validators\EmailExists::__construct(), 0 passed and exactly 1 expected, which is somewhat expected since the AbstractRule does not have a PDO injected and my class extends it.

So how to inject the PDO interface so that I can use it in my custom rules?

Are you guys using another approach in validating this kind of data? Do note that I am writing an API, so the database validation is somewhat a must and after Googling for past two days, I have no solutions at hand.

I am also using a PHP-DI where I create PDO interface. This is my dependencies.php file:

declare(strict_types=1);

use DI\ContainerBuilder;
use Psr\Container\ContainerInterface;
use app\Handlers\SessionMiddleware;

return function (ContainerBuilder $containerBuilder) {
    $containerBuilder->addDefinitions([
        PDO::class => function (ContainerInterface $c) {
            $settings = $c->get('settings')['db'];

            $db = new PDO("mysql:host={$settings['host']};dbname={$settings['database']};charset={$settings['charset']},{$settings['username']},{$settings['password']}");
            $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            $db->setAttribute(PDO::MYSQL_ATTR_INIT_COMMAND, "SET NAMES 'utf8',time_zone='{$offset}'");
            $db->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);

            return $db;
        },
        'session' => function(ContainerInterface $c) {
            return new SessionMiddleware;
        }
    ]);
};

And (part of) index.php:

declare(strict_types=1);

use DI\ContainerBuilder;
use Slim\Factory\AppFactory;

// Instantiate PHP-DI ContainerBuilder
$containerBuilder = new ContainerBuilder();

// Set up settings
$settings = require __DIR__ . '/../app/settings.php';
$settings($containerBuilder);

// Set up dependencies
$dependencies = require __DIR__ . '/../app/dependencies.php';
$dependencies($containerBuilder);

// Build PHP-DI Container instance
$container = $containerBuilder->build();

// Instantiate the app
AppFactory::setContainer($container);
$app = AppFactory::create();

// Register middleware
$middleware = require __DIR__ . '/../app/middleware.php';
$middleware($app);

// Register routes
$routes = require __DIR__ . '/../app/routes.php';
$routes($app);

// Add Routing Middleware
$app->addRoutingMiddleware();

// Run App & Emit Response
$response = $app->handle($request);
$responseEmitter = new ResponseEmitter();
$responseEmitter->emit($response);

Any help would be appreciated.

score 2 · Answer 1 · answered Oct 25 '19 at 08:58

Use your user model to count the number of rows in the user table where there is a hit. If it is not exactly 0, the check returns false, if it is exactly 0, the check passes. So you don't have to include a PDO at this point. I use Slim 3 and that works quite well.

namespace app\Validators;

use Respect\Validation\Rules\AbstractRule;

class EmailAvailable extends AbstractRule {

        /**
         * @param $input
         *
         * @return bool
         */
        public function validate ($sInput) {
            return User::where('user_email', $sInput)->count() === 0;
        }
    }

score 0 · Answer 2 · answered Oct 24 '19 at 12:37

0

class EmailAvailable extends AbstractRule {

    /**
     * @param $input
     *
     * @return bool
     */
    public function validate ($sInput) {
        return User::where('user_email', $sInput)->count() === 0;
    }
}

answered Oct 24 '19 at 12:37

czk

1

3

Please don't post only code as answer,but include an explanation what your code does and how it solves the problem of the question. Answers with an explanation are generally of higher quality, and are more likely to attract upvotes. – Mark Rotteveel Oct 24 '19 at 15:42

Respect\Validation custom Rule with PDO?

2 Answers2