服务中的 Symfony 4 会话

Question

I'm trying to use session variables in my custom service.

I already set add the following lines to services.yaml

MySession:
    class: App\Services\SessionTest
    arguments: ['@session', '@service_container']

And my SessionTest looks like this

namespace App\Services;

use Symfony\Component\HttpFoundation\Session\SessionInterface;
use Symfony\Component\HttpFoundation\Request;

class SessionTest
{
    public $session;

    public function __construct()
    {

    }
    public function index()
    {
        echo "<pre>";
        var_dump($this->session);
        echo "</pre>";
    }
}

And receive this error: Too few arguments to function App\Services\SessionTest::__construct(), 0 passed in /var/www/app.dev/src/Controller/OrdersController.php on line 33 and exactly 1 expected

Answer 1

You are using constructor injection in your config, but it looks like you're trying to accept property injection in TestSession .

The container will be generated with code like approximately this:

new SessionTest(SessionInterface $session, ContainterInterface $container)

So you either need to change TestSession to accept '@session' and '@service_container' as constructor arguments:

protected $session;
protected $serviceContainer;

public function __construct(SessionInterface $session, ContainterInterface $serviceContainer)
{
    $this->sessions = $session;
    $this->serviceContainer = $container;
}

Or you need to change your config to something like this:

MySession:
    class: App\Services\SessionTest
    properties:
        session: '@session'
        serviceContainer: '@service_container'

You will also need to add

   public $serviceContainer;

to TestSession if you want to inject the service container as a property.