SoFunction
Updated on 2025-04-04

Introduction to the service provider and facade model in Laravel

Preface

In laravel, when we need to use the classes we added, we can create a folder to store class files specifically, or we can use the service provider of laravel.

The two are actually not very different. The main reason is that if the former is used, it will generate dependencies with the business code. Imagine that if a controller refers to many custom class files, then you can imagine how many dependencies will be generated. Therefore, we can use the service provider to register classes in the laravel container. In this way, we can manage dependencies in a separate configuration file, and logic and post-maintenance will be much more convenient.

The main thing to use the storefront is that you don’t need to instantiate the class. You can use static methods to access the class methods, which is more convenient to use. However, this actually has disadvantages. For example, you cannot jump directly to the corresponding method, and you cannot intuitively understand the usage of this method. Personal development may not have much impact, but if developed by the team, it may actually make people a little dizzy when used.

Taking Laravel's own file system as an example, a service provider is registered in the providers array of the configuration file of config/:

Illuminate\Filesystem\FilesystemServiceProvider::class,

A facade is defined in the alias array:

‘File' => Illuminate\Support\Facades\File::class,

Through these two steps, we can use the file system-related operations provided by Laravel very conveniently, and the call form is very simple, such as:

  • File::exist($path), determine whether the file exists.
  • File::get($path, $lock = false), get the contents of a file.
  • File::append($path, $data), append the content to the end of a file.
  • File::files($directory), get all files in a directory.

So how did this be done? Let’s talk about Laravel’s service provider and storefront model respectively.

Service Provider

Let's take a look at the definition first:

The service provider is the center of all Laravel applications launch. Including your own applications, as well as all Laravel core services, are launched through the service provider.

In the file system service provider, you can see that a singleton is bound to the /vendor/laravel/framework/src/Illuminate/Filesystem/ register method:

protected function registerNativeFilesystem()
{
 $this->app->singleton('files', function () {
  return new Filesystem;
 });
}

This singleton is the singleton pattern of the Filesystem class. Of course, this service provider can also bind other singletons or do more. We're only studying hereFile::exist() The principle of this calling method.

Then in this way there is a singleton of files, which is actually an instance of the Filesystem class.

At this time, if there is no Facade, the method of the Filesystem instance can also be called, then this is called:

app(‘files')->exist($path)

OK, let’s start talking about Facade now.

Facade facade mode

Let's take a look at the introduction:

Facades /fəˈsäd/ provides a "static" interface for classes available in the application's service container. Laravel comes with many facades that can be used to access almost all of its services. Laravel facades are the "static proxy" of the base classes in the service container. Compared with traditional static method calls, facades provide a more concise and rich syntax, while also providing better testability and scalability.

At the beginning of this article, alias array defines a File, and the specific class is

Illuminate\Support\Facades\File::class,

Its content is:

class File extends Facade
{
 /**
  * Get the registered name of the component.
  *
  * @return string
  */
 protected static function getFacadeAccessor()
 {
  return 'files';
 }
}

It actually returns a name. Note that this name files is not the name of the singleton pattern that just bound? That's right.

In this way, you can use the alias File or facade to call the methods in this Filesystem instance.

Through this article, I hope you can understand the relationship between the service provider, Facade, and the instance of the actually called class.

Summarize

The above is the entire content of this article. I hope that the content of this article has a certain reference value for everyone's study or work. If you have any questions, you can leave a message to communicate. Thank you for your support.