controller.php

<?php

namespace ActivismBe\Controllers;

use Silex\Application;
use ActivismBe\Models\User;
use Silex\Api\ControllerProviderInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Validator\Constraints as Assert;

class AuthController implements ControllerProviderInterface
{
    /**
     * Variable used to put the app instance in.
     *
     * @var mixed
     */
    private $app;

    /**
     * IndexController instance.
     *
     * @param  \Silex\Application $app
     * @return void.
     */
    public function __construct($app)
    {
        $this->app = $app;
    }

    /**
     * Factory routing instance.
     *
     * @param  Application $app
     * @return mixed
     */
    public function connect(Application $app)
    {
        $factory = $app['controllers_factory'];

        $factory->get('/login',     [$this, 'loginView'])->bind('login.view');
        $factory->get('/register',  [$this, 'registerView'])->bind('register.view');
        $factory->post('/login',    [$this, 'authenticate'])->bind('login.authenticate');
        $factory->post('/register', [$this, 'registerMethod'])->bind('register.method');

        return $factory;
    }

    /**
     *
     */
    public function loginView()
    {
        $data['errors'] = [];
        return $this->app['twig']->render('auth\login.html.twig', $data);
    }

    /**
     * Authencation controller with the given user input.
     *
     * @see    POST: http://www.domain.tld/auth/login
     * @param  Request $input
     * @return Redirect
     */
    public function authenticate(Request $input)
    {
        $constraints['email']    = [ new Assert\NotBlank(), new Assert\Email() ];
        $constraints['password'] = [ new Assert\NotBlank() ];

        $errors['validation'] = $this->app['validator']->validate($input->request->all(), new Assert\Collection($constraints));
        $MySQL['credentials'] = User::where('email', $input->get('email'))
            ->with(['permissions'])
            ->where('password', md5($input->get('password')))
            ->where('blocked', 'N');

        if (count($errors['validation']) > 0 || $MySQL['credentials']->count() === 0) { // There are errors
            $data['errors'] = $errors;
            return $this->app['twig']->render('auth\login.html.twig', $data);
        }

        // No errors so we can move on with the auth method.
        $authencation = [];
        $permissions  = [];

        foreach ($MySQL['credentials']->get() as $user) { // Define the data to the session array's.
            // Building up the session.
            foreach ($user->permissions as $perm) {
                array_push($permissions, $perm->role); // Push every key invidual to the permissions array.
            }

            $authencation['id']             = $user->id;
            $authencation['name']           = $user->name;
            $authencation['email']          = $user->email;
            $authencation['permissions']    = $permissions;
        }

        $this->app['session']->set('logged_in', $authencation);
        return $this->app->redirect('backend');
    }

    /**
     * Register view for a new user.
     *
     * @see    GET|HEAD: http://www.domain.tld/auth/register
     * @return Twig view.
     */
    public function registerView()
    {
        $data['title'] = 'Register';
        return $this->app['twig']->render('auth\register', $data);
    }

    /**
     *
     */
    public function registerMethod()
    {

    }
}

view.html.twig

{% if errors %}
<ul>
{% for error in errors %}
<li>{{ error }}</li>
{% endfor %}
</ul>
{% endif %}

<form class="http://localhost:8000/auth/login" method="post">
    <input type="text" name="email" placeholder="email">
    <input type="text" name="password" value="password">
    <button type="submit">Submmit</button>
</form>