php dependency injection in method not working - php

Question

I am trying to get use dependency injection in methods via type hint. its not working for me. calling $container->get(Name::class); works
if (false === file_exists(__DIR__ . '/../vendor/autoload.php')) {
die('Install the composer dependencies');
}
require __DIR__ . '/../vendor/autoload.php';
//(new Dotenv())->bootEnv(dirname(__DIR__) . '/.env');
/* Load external routes file */
require_once dirname(__DIR__) . '/config/routes.php';
$builder = new DI\ContainerBuilder();
$builder->addDefinitions(dirname(__DIR__) . '/config/Definitions.php');
try {
$builder->useAutowiring(true);
$container = $builder->build();
} catch (Exception $e) {
die($e->getMessage());
}
function test(Cache $cache)
{
dd($cache);
}
test();
die;
The Definitions file
<?php
declare(strict_types = 1);
use Psr\Container\ContainerInterface;
require dirname(__DIR__) . '/config/config.php';
return [
Cache::class => DI\create(Cache::class)->constructor(MEMCACHED_SERVERS),
\Twig\Environment::class => function () {
$loader = new \Twig\Loader\FilesystemLoader(dirname(__DIR__) . '/Views/');
$twig = new \Twig\Environment($loader, [
'cache' => dirname(__DIR__) . '/Cache/'
]);
return $twig;
},
];
The error i am getting :
Fatal error: Uncaught ArgumentCountError: Too few arguments to
function test(), 0 passed

Answer 1

That’s because you made the test function require Cache then when you run test() you don’t inject the Cache object here:
function test(Cache $cache)
{
dd($cache);
}
// here you need to pass instance of Cache
test();
I am not familiar with this code base, but you would either need an auto-injection script based on Reflection, or what-have-you, to do that auto-injection or you need to manually pass the Cache object:
test(new Cache);
If the Cache object uses all static methods or class constants, you don't need to create it injectable, you would just use it where it's required as in the script referenced by Cache::class;
One last possibility is that $cache is available in some include in one of those files somewhere, though I don't see that anywhere, but if that is available, you could make a test() a variable function with use():
$test = function() use ($cache)
{
dd($cache);
};
// No injection needed
$test();