Norvica [Container]

Getting Started

Requires PHP 8.2+.

Use the container for configuring service instantiation and dependency injection. It’s designed as a service container, not a factory, meaning it will instantiate a service only once and return the same instance for all subsequent requests (singleton pattern). If you need to create multiple instances of an object, consider creating a factory service and registering it within the container.

Install

This library is installed using Composer. If you don’t have Composer, you can get it from getcomposer.org.

In your project’s root directory, run the following command:

composer require norvica/container

Create a Configuration

Define your services in a PHP file (e.g., container.php):

// container.php

use Norvica\Container\Definition\Env;
use function Norvica\Container\obj;

return [
    'logger' => obj(Logger::class),
    'mailer' => obj(Mailer::class, to: '[email protected]'),
    'api_client' => static fn(#[Env('API_KEY')] $apiKey) => new ApiClient($apiKey),
];

Instantiate the Container

Use the Configurator class to load your configuration and build the container instance:

use Norvica\Container\Configurator;

$configurator = new Configurator();
$configurator->load(__DIR__ . '/container.php');

$container = $configurator->container();

Resolve Dependencies

You can now request services from the container using the get() method:

$logger = $container->get('logger');
$mailer = $container->get('mailer');

Putting It All Together

Example:

// index.php
require 'vendor/autoload.php';

use Norvica\Container\Configurator;
use Monolog\Logger;

// ... container.php (as defined above)

$configurator = new Configurator();
$configurator->load(__DIR__ . '/container.php');
$container = $configurator->container();

$logger = $container->get('logger');
$logger->info('This is a log message.');

In this example:

  • We require Composer’s autoloader.
  • We define a Logger service in container.php.
  • We instantiate the Configurator, load the configuration file, and build the container.
  • We get the logger service from the container and use it to log a message.

Key Points to Remember:

  • Service IDs: Use descriptive names for your service IDs to make your configuration readable.
  • Dependency Resolution: The container automatically resolves dependencies between your services based on type hints and the configuration you provide.
  • Singleton Scope: Services are created as singletons, meaning the container will return the same instance each time you request it.
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Container Configuration