Quick Start

Create the Container

use Solo\Container\Container;

$container = new Container();

Register Services

A factory builds a service. It receives the container, to fetch what the service needs:

$container->set(Config::class, fn() => new Config(__DIR__ . '/config.php'));
$container->set(Database::class, fn($c) => new Database($c->get(Config::class)->dsn));

An id is a string: usually a class or interface name, or a name of your own for a value no type stands for:

$container->set('app.name', fn() => 'Shop');

Bind Interfaces

$container->bind(LoggerInterface::class, FileLogger::class);

get(LoggerInterface::class) now resolves FileLogger.

Resolve Services

$users = $container->get(UserRepository::class);

UserRepository has no registration, so the container builds it from its constructor:

final class UserRepository
{
    public function __construct(
        private Database $database,      // from the Database factory
        private LoggerInterface $logger, // a FileLogger, through the binding
    ) {
    }
}

Each id is built once; later calls return the same instance:

$container->get(UserRepository::class) === $container->get(UserRepository::class); // true

Service Providers

An application often groups its registrations in service providers. Typing them against WritableContainerInterface, which adds set() to PSR-11, keeps them independent of this implementation:

use Solo\Contracts\Container\WritableContainerInterface;

final class DatabaseServiceProvider
{
    public function register(WritableContainerInterface $container): void
    {
        $container->set(Connection::class, fn($c) => new Connection(
            $c->get(Config::class)->dsn,
        ));
    }
}

PHPStan infers the untyped $c as the container and $c->get(Config::class) as a Config — see Static Analysis.

Handle Errors

use Psr\Container\NotFoundExceptionInterface;

try {
    $mailer = $container->get('mailer');
} catch (NotFoundExceptionInterface $e) {
    // Service 'mailer' not found in container.
}

NotFoundException means the container does not know the id; ContainerException means it knows the id but cannot build it. See Exceptions.

Next Steps

• Services & Factories — Registering, replacing and resetting services
• Auto-wiring — How constructor parameters are resolved
• Lazy Services — Deferred construction with native proxies