Difference between Service Container and Service Provider in Laravel

Let us first understand how we generally use service containers and service providers.

The recommended and most organized way to register services (bindings) in Laravel is via service providers, you're not strictly bound to this method. The service container can be used directly without involving service providers.

Let's go through two examples to understand this:

1. Using Service Providers (The Common Way):

Assuming you want to bind an interface PaymentGatewayInterface to a concrete class StripePaymentGateway, the common way is to use a service provider.

In a service provider, such as AppServiceProvider, you might have:

use App\Interfaces\PaymentGatewayInterface;
use App\Services\StripePaymentGateway;

public function register()
{
    $this->app->bind(PaymentGatewayInterface::class, StripePaymentGateway::class);
}

When you bootstrap your application, Laravel loads all service providers, and during this process, your binding gets registered in the service container.

2. Using Service Container Directly:

Now, let's say you're within a controller or some route closure and decide to bind the same interface to the concrete class. This is not the most organized way, but it's possible.

In a route or a controller:

use Illuminate\Support\Facades\App;
use App\Interfaces\PaymentGatewayInterface;
use App\Services\StripePaymentGateway;

// Directly using the service container
App::bind(PaymentGatewayInterface::class, StripePaymentGateway::class);

In this example, you bypassed the service provider altogether and used the service container directly to bind the interface to its implementation.
Why is the Service Provider method preferred?

• Organization: Grouping related IoC registrations in specific service providers helps keep the codebase organized and maintainable.
• Laziness: Using service providers, you can defer the loading of some services until they are actually needed.
• Bootstrapping: The boot method in service providers allows you to perform actions after all bindings have been registered which lets us know if dependencies are available.

Key Difference:

While both can be used for bindings, the main distinction is "binding vs. bootstrapping." The service container's main job is to manage bindings and resolve dependencies. In contrast, the service provider's role is broader, bootstrapping and configuring various parts of the application.
Conclusion:
In essence, while there's overlap in their roles, especially regarding bindings, they operate at different levels and stages of the application's lifecycle.