Problems encountered when developing and setting up lazy loading in Laravel Service Provider

This article mainly introduces you to the problems encountered when developing and setting up lazy loading in Laravel Service Provider. The article introduces it in great detail through sample code. It has certain reference learning value for everyone's study or work. Friends who need it can follow Let’s take a look with the editor. Hope it helps everyone.

Preface

This article mainly introduces some problems encountered when setting up lazy loading in Laravel Service Provider. All this article is due to actual project needs. Recently, I am developing laravel-database- When using the logger package, I found that setting the ServiceProvider defer attribute to true will cause the middleware registered in the register method to be invalid.

class ServiceProvider extends \Illuminate\Support\ServiceProvider
{
 protected $defer = true; 
 public function register()
 {
 $this->mergeConfigFrom(
  __DIR__ . '/../config/config.php', 'ibrand.dblogger'
 );
 $this->app->singleton(DbLogger::class, function ($app) {
  return new DbLogger();
 });
 //当 $defer 设置为 true 时，在路由中引用 databaselogger middleware 会报错，提示 databaselogger class not found.
 $this->app[\Illuminate\Routing\Router::class]->middleware('databaselogger', Middleware::class);

 } 
 public function provides()
 {
 return [DbLogger::class];
 }
}

When the problem occurred, I suspected that it was caused by setting the defer attribute to true. I immediately modified the source code and commented out the protected $defer = true; code. The result was still the prompt databaselogger class not found. . , indicating that Laravel has not registered this ServiceProvder

The next step is how to solve this problem, and I tried the following methods:

1. Verify whether there is a problem with the code itself

Register your own ServiceProvider in the normally registered AppServiceProvider

public function register()
 {
 //
 $this->app->register(\Ibrand\DatabaseLogger\ServiceProvider::class);
 }

After registration, everything is normal.

2. Study the source code

The provider registration in config/app.php is invalid, but the registration in other ServiceProviders is valid, indicating another problem.

Find the registerConfiguredProviders method by studying the Illuminate\Foundation\Application source code:

Laravel reads the providers content in config/app.php in this method and loads it into ProviderRepository.

(new ProviderRepository($this, new Filesystem, $this->getCachedServicesPath()))
     ->load($providers->collapse()->toArray());

The focus is on $this->getCachedServicesPath(). Through the source code, we found that Laravel determines how to register the ServiceProvider based on the bootstrap/cache/services.php file.

At this time, I thought of the reason why the //protected $defer = true; code was still invalid after commenting it before.

So in order to make the commented //protected $defer = true; code effective, you need to execute

php artisan clear-compiled 
php artisan optimize

After that, the problem is solved, and you have a deeper understanding of the principle of ServiceProvider.

So remember: If you plan to use delayed loading of ServiceProvider, it is strictly prohibited to register middleware, route and other series of operations. At the same time, after changing the defer attribute value, you need to execute php artisan clear-compiled and php artisan optimize to update the ServiceProvider cache.

3. Why is registration in AppServiceProvider valid?

It is very simple, because AppServiceProvider does not delay loading, so executing the register method in AppServiceProvider to register a new ServiceProvider will not delay loading.

Summary

Use lazy loading ServiceProvider with caution

After changing the defer attribute value, you need to execute php artisan clear-compiled and php artisan optimize to update the ServiceProvider cache.

It is strictly prohibited to register middleware and route in the delayed-loaded ServiceProvider.

Related recommendations:

Laravel Service Providers problem

Laravel Service Providers binds multiple implementations. When doing dependency injection, what should I do? Determine which class is instantiated?

Laravel Service Provider Solution to problems encountered when setting up lazy loading during development

The above is the detailed content of Problems encountered when developing and setting up lazy loading in Laravel Service Provider. For more information, please follow other related articles on the PHP Chinese website!