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But, what do we mean by “bootstrapped”? In general, we mean registering things, including registering service container bindings, event listeners, middleware, and even routes. Service providers are the central place to configure your application.
If you open the config/app.php file included with Laravel, you will see a providers array. These are all of the service provider classes that will be loaded for your application. By default, a set of Laravel core service providers are listed in this array. These providers bootstrap the core Laravel components, such as the mailer, queue, cache, and others. Many of these providers are “deferred” providers, meaning they will not be loaded on every request, but only when the services they provide are actually needed.
In this overview, you will learn how to write your own service providers and register them with your Laravel application.
All service providers extend the Illuminate\Support\ServiceProvider class. Most service providers contain a register and a boot method. Within the register method, you should only bind things into the . You should never attempt to register any event listeners, routes, or any other piece of functionality within the register method.
As mentioned previously, within the register method, you should only bind things into the . You should never attempt to register any event listeners, routes, or any other piece of functionality within the register method. Otherwise, you may accidentally use a service that is provided by a service provider which has not loaded yet.
Let’s take a look at a basic service provider. Within any of your service provider methods, you always have access to the $app property which provides access to the service container:
<?php namespace App\Providers; use App\Services\Riak\Connection;use Illuminate\Contracts\Foundation\Application;use Illuminate\Support\ServiceProvider; class RiakServiceProvider extends ServiceProvider{ /** * Register any application services. */ public function register(): void { $this->app->singleton(Connection::class, function (Application $app) { return new Connection(config('riak')); }); }}
This service provider only defines a register method, and uses that method to define an implementation of App\Services\Riak\Connection in the service container. If you’re not yet familiar with Laravel’s service container, check out its documentation.
The bindings And singletons Properties
If your service provider registers many simple bindings, you may wish to use the and singletons properties instead of manually registering each container binding. When the service provider is loaded by the framework, it will automatically check for these properties and register their bindings:
The Boot Method
So, what if we need to register a within our service provider? This should be done within the boot method. This method is called after all other service providers have been registered, meaning you have access to all other services that have been registered by the framework:
<?php namespace App\Providers; use Illuminate\Support\Facades\View;use Illuminate\Support\ServiceProvider; class ComposerServiceProvider extends ServiceProvider{ /** * Bootstrap any application services. */ public function boot(): void { View::composer('view', function () { // ... }); }}
Boot Method Dependency Injection
All service providers are registered in the config/app.php configuration file. This file contains a providers array where you can list the class names of your service providers. By default, a set of Laravel core service providers are listed in this array. These providers bootstrap the core Laravel components, such as the mailer, queue, cache, and others.
To register your provider, add it to the array:
'providers' => [ // Other Service Providers App\Providers\ComposerServiceProvider::class,],
If your provider is only registering bindings in the , you may choose to defer its registration until one of the registered bindings is actually needed. Deferring the loading of such a provider will improve the performance of your application, since it is not loaded from the filesystem on every request.
Laravel compiles and stores a list of all of the services supplied by deferred service providers, along with the name of its service provider class. Then, only when you attempt to resolve one of these services does Laravel load the service provider.
To defer the loading of a provider, implement the \Illuminate\Contracts\Support\DeferrableProvider interface and define a method. The provides method should return the service container bindings registered by the provider:
