laravel-cart/src/CartServiceProvider.php

<?php

namespace Pixeldigital\Cart;

use Illuminate\Support\ServiceProvider;

class CartServiceProvider extends ServiceProvider
{
    /**
     * Indicates if loading of the provider is deferred.
     *
     * @var bool
     */
    protected $defer = false;

    /**
     * Boot the service provider.
     */
    public function boot()
    {
        if ($this->app->runningInConsole()) {
            $this->publishes([
                __DIR__ . '/../config/config.php' => config_path('cart.php'),
            ], 'config');
        }
    }

    /**
     * Register the service provider.
     *
     * @return void
     */
    public function register()
    {
        $this->mergeConfigFrom(__DIR__ . '/../config/config.php', 'cart');

        $this->app->singleton('cart', function ($app) {
            $storageClass = config('cart.storage');
            $eventsClass = config('cart.events');

            $storage = $storageClass ? new $storageClass : $app['session'];
            $events = $eventsClass ? new $eventsClass : $app['events'];
            $instanceName = 'cart';

            // default session or cart identifier. This will be overridden when calling Cart::session($sessionKey)->add() etc..
            // like when adding a cart for a specific user name. Session Key can be string or maybe a unique identifier to bind a cart
            // to a specific user, this can also be a user ID
            $session_key = '4yTlTDKu3oJOfzD';

            return new Cart(
                $storage,
                $events,
                $instanceName,
                $session_key,
                config('cart')
            );
        });
    }

    /**
     * Get the services provided by the provider.
     *
     * @return array
     */
    public function provides()
    {
        return [];
    }
}