03. ServiceProvider Register 解析

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ServiceProvider Register 解析

前面 《02. Kernel Handle解析》 结尾，我们留下了 注册服务提供者 和 启动服务提供者 是两个比较重要的步骤的悬念，接下来两篇文章，我们来分别解析这两大流程。

代码

laravel/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/RegisterProviders.php

Lines 1 to 19 in d081c91

	<?php
	namespace Illuminate\Foundation\Bootstrap;
	use Illuminate\Contracts\Foundation\Application;
	class RegisterProviders
	{
	/**
	* Bootstrap the given application.
	*
	* @param \Illuminate\Contracts\Foundation\Application $app
	* @return void
	*/
	public function bootstrap(Application $app)
	{
	$app->registerConfiguredProviders();
	}
	}

解析

整个 RegisterProviders 都是粮衣，其没有任何功能功能代码，而是调用到了 Illuminate\Foundation\ Application 的 registerConfiguredProviders

注意运行时实际并没有调用 Illuminate\Contracts\Foundation\Application 的 registerConfiguredProviders，而是调用了其具体实现类 Illuminate\Foundation\ Application 的 registerConfiguredProviders。不要被上面代码中的注解表象所迷惑

laravel/vendor/laravel/framework/src/Illuminate/Foundation/Application.php

Lines 533 to 549 in d081c91

	/**
	* Register all of the configured providers.
	*
	* @return void
	*/
	public function registerConfiguredProviders()
	{
	$providers = Collection::make($this->config['app.providers'])
	->partition(function ($provider) {
	return Str::startsWith($provider, 'Illuminate\\');
	});
	$providers->splice(1, 0, [$this->make(PackageManifest::class)->providers()]);
	(new ProviderRepository($this, new Filesystem, $this->getCachedServicesPath()))
	->load($providers->collapse()->toArray());
	}

上面第 540-543 行是将 config/app.php 中配置的 providers

laravel/config/app.php

Lines 122 to 163 in d081c91

	'providers' => [
	/*
	* Laravel Framework Service Providers...
	*/
	Illuminate\Auth\AuthServiceProvider::class,
	Illuminate\Broadcasting\BroadcastServiceProvider::class,
	Illuminate\Bus\BusServiceProvider::class,
	Illuminate\Cache\CacheServiceProvider::class,
	Illuminate\Foundation\Providers\ConsoleSupportServiceProvider::class,
	Illuminate\Cookie\CookieServiceProvider::class,
	Illuminate\Database\DatabaseServiceProvider::class,
	Illuminate\Encryption\EncryptionServiceProvider::class,
	Illuminate\Filesystem\FilesystemServiceProvider::class,
	Illuminate\Foundation\Providers\FoundationServiceProvider::class,
	Illuminate\Hashing\HashServiceProvider::class,
	Illuminate\Mail\MailServiceProvider::class,
	Illuminate\Notifications\NotificationServiceProvider::class,
	Illuminate\Pagination\PaginationServiceProvider::class,
	Illuminate\Pipeline\PipelineServiceProvider::class,
	Illuminate\Queue\QueueServiceProvider::class,
	Illuminate\Redis\RedisServiceProvider::class,
	Illuminate\Auth\Passwords\PasswordResetServiceProvider::class,
	Illuminate\Session\SessionServiceProvider::class,
	Illuminate\Translation\TranslationServiceProvider::class,
	Illuminate\Validation\ValidationServiceProvider::class,
	Illuminate\View\ViewServiceProvider::class,
	/*
	* Package Service Providers...
	*/
	/*
	* Application Service Providers...
	*/
	App\Providers\AppServiceProvider::class,
	App\Providers\AuthServiceProvider::class,
	// App\Providers\BroadcastServiceProvider::class,
	App\Providers\EventServiceProvider::class,
	App\Providers\RouteServiceProvider::class,
	],

读取出来，判断是否为 Illuminate\ 开头，归为两组：

Illuminate\Support\Collection {#2825
     all: [
       Illuminate\Support\Collection {#2822
         all: [
            "Illuminate\Auth\AuthServiceProvider",
            "Illuminate\Broadcasting\BroadcastServiceProvider",
            "Illuminate\Bus\BusServiceProvider",
            "Illuminate\Cache\CacheServiceProvider",
            "Illuminate\Foundation\Providers\ConsoleSupportServiceProvider",
            "Illuminate\Cookie\CookieServiceProvider",
            "Illuminate\Database\DatabaseServiceProvider",
            "Illuminate\Encryption\EncryptionServiceProvider",
            "Illuminate\Filesystem\FilesystemServiceProvider",
            "Illuminate\Foundation\Providers\FoundationServiceProvider",
            "Illuminate\Hashing\HashServiceProvider",
            "Illuminate\Mail\MailServiceProvider",
            "Illuminate\Notifications\NotificationServiceProvider",
            "Illuminate\Pagination\PaginationServiceProvider",
            "Illuminate\Pipeline\PipelineServiceProvider",
            "Illuminate\Queue\QueueServiceProvider",
            "Illuminate\Redis\RedisServiceProvider",
            "Illuminate\Auth\Passwords\PasswordResetServiceProvider",
            "Illuminate\Session\SessionServiceProvider",
            "Illuminate\Translation\TranslationServiceProvider",
            "Illuminate\Validation\ValidationServiceProvider",
            "Illuminate\View\ViewServiceProvider",
         ],
       },
       Illuminate\Support\Collection {#2823
         all: [
            "22" => "App\Providers\AppServiceProvider",
            "22" => "App\Providers\AuthServiceProvider",
            "22" => "App\Providers\EventServiceProvider",
            "22" => "App\Providers\RouteServiceProvider",
         ],
       },
     ],
   }

接着 $providers->splice(1, 0, [$this->make(PackageManifest::class)->providers()]) 这一行会得到如下结果

Illuminate\Support\Collection {#33
  #items: array:3 [
    0 => Illuminate\Support\Collection {#21
      #items: array:22 [
        0 => "Illuminate\Auth\AuthServiceProvider"
        1 => "Illuminate\Broadcasting\BroadcastServiceProvider"
        2 => "Illuminate\Bus\BusServiceProvider"
        3 => "Illuminate\Cache\CacheServiceProvider"
        4 => "Illuminate\Foundation\Providers\ConsoleSupportServiceProvider"
        5 => "Illuminate\Cookie\CookieServiceProvider"
        6 => "Illuminate\Database\DatabaseServiceProvider"
        7 => "Illuminate\Encryption\EncryptionServiceProvider"
        8 => "Illuminate\Filesystem\FilesystemServiceProvider"
        9 => "Illuminate\Foundation\Providers\FoundationServiceProvider"
        10 => "Illuminate\Hashing\HashServiceProvider"
        11 => "Illuminate\Mail\MailServiceProvider"
        12 => "Illuminate\Notifications\NotificationServiceProvider"
        13 => "Illuminate\Pagination\PaginationServiceProvider"
        14 => "Illuminate\Pipeline\PipelineServiceProvider"
        15 => "Illuminate\Queue\QueueServiceProvider"
        16 => "Illuminate\Redis\RedisServiceProvider"
        17 => "Illuminate\Auth\Passwords\PasswordResetServiceProvider"
        18 => "Illuminate\Session\SessionServiceProvider"
        19 => "Illuminate\Translation\TranslationServiceProvider"
        20 => "Illuminate\Validation\ValidationServiceProvider"
        21 => "Illuminate\View\ViewServiceProvider"
      ]
    }
    1 => array:5 [
      0 => "BeyondCode\DumpServer\DumpServerServiceProvider"
      1 => "Fideloper\Proxy\TrustedProxyServiceProvider"
      2 => "Laravel\Tinker\TinkerServiceProvider"
      3 => "Carbon\Laravel\ServiceProvider"
      4 => "NunoMaduro\Collision\Adapters\Laravel\CollisionServiceProvider"
    ]
    2 => Illuminate\Support\Collection {#31
      #items: array:4 [
        22 => "App\Providers\AppServiceProvider"
        23 => "App\Providers\AuthServiceProvider"
        24 => "App\Providers\EventServiceProvider"
        25 => "App\Providers\RouteServiceProvider"
      ]
    }
  ]
}

最后一句代码

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

第一步是将加载缓存好的 bootstrap/cache/services.php

laravel/vendor/laravel/framework/src/Illuminate/Foundation/Application.php

Lines 855 to 863 in d081c91

	/**
	* Get the path to the cached services.php file.
	*
	* @return string
	*/
	public function getCachedServicesPath()
	{
	return $this->bootstrapPath().'/cache/services.php';
	}

其实就是执行 ProviderRepository::load() $providers-> collapse() 得到的数组 (这个数组是前面 splice 拆分后再并入的)。

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 47 to 79 in d081c91

	/**
	* Register the application service providers.
	*
	* @param array $providers
	* @return void
	*/
	public function load(array $providers)
	{
	$manifest = $this->loadManifest();
	// First we will load the service manifest, which contains information on all
	// service providers registered with the application and which services it
	// provides. This is used to know which services are "deferred" loaders.
	if ($this->shouldRecompile($manifest, $providers)) {
	$manifest = $this->compileManifest($providers);
	}
	// Next, we will register events to load the providers for each of the events
	// that it has requested. This allows the service provider to defer itself
	// while still getting automatically loaded when a certain event occurs.
	foreach ($manifest['when'] as $provider => $events) {
	$this->registerLoadEvents($provider, $events);
	}
	// We will go ahead and register all of the eagerly loaded providers with the
	// application so their services can be registered with the application as
	// a provided service. Then we will set the deferred service list on it.
	foreach ($manifest['eager'] as $provider) {
	$this->app->register($provider);
	}
	$this->app->addDeferredServices($manifest['deferred']);
	}

这句 loadManifest 即为加载前面传入的 bootstrap/cache/services.php

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 81 to 98 in d081c91

	/**
	* Load the service provider manifest JSON file.
	*
	* @return array|null
	*/
	public function loadManifest()
	{
	// The service manifest is a file containing a JSON representation of every
	// service provided by the application and whether its provider is using
	// deferred loading or should be eagerly loaded on each request to us.
	if ($this->files->exists($this->manifestPath)) {
	$manifest = $this->files->getRequire($this->manifestPath);
	if ($manifest) {
	return array_merge(['when' => []], $manifest);
	}
	}
	}

第60行调用到的的 shouldRecompile 逻辑为判断是否 provider 不符合，代码

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 100 to 110 in d081c91

	/**
	* Determine if the manifest should be compiled.
	*
	* @param array $manifest
	* @param array $providers
	* @return bool
	*/
	public function shouldRecompile($manifest, $providers)
	{
	return is_null($manifest) || $manifest['providers'] != $providers;
	}

如果需要重新编译此服务提供者缓存的 bootstrap/cache/services.php ，把数据 $manifest 提取到 bootstrap/cache/services.php ，具体过程为：

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 130 to 166 in d081c91

	/**
	* Compile the application service manifest file.
	*
	* @param array $providers
	* @return array
	*/
	protected function compileManifest($providers)
	{
	// The service manifest should contain a list of all of the providers for
	// the application so we can compare it on each request to the service
	// and determine if the manifest should be recompiled or is current.
	$manifest = $this->freshManifest($providers);
	foreach ($providers as $provider) {
	$instance = $this->createProvider($provider);
	// When recompiling the service manifest, we will spin through each of the
	// providers and check if it's a deferred provider or not. If so we'll
	// add it's provided services to the manifest and note the provider.
	if ($instance->isDeferred()) {
	foreach ($instance->provides() as $service) {
	$manifest['deferred'][$service] = $provider;
	}
	$manifest['when'][$provider] = $instance->when();
	}
	// If the service providers are not deferred, we will simply add it to an
	// array of eagerly loaded providers that will get registered on every
	// request to this application instead of "lazy" loading every time.
	else {
	$manifest['eager'][] = $provider;
	}
	}
	return $this->writeManifest($manifest);
	}

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 179 to 198 in d081c91

	/**
	* Write the service manifest file to disk.
	*
	* @param array $manifest
	* @return array
	*
	* @throws \Exception
	*/
	public function writeManifest($manifest)
	{
	if (! is_writable(dirname($this->manifestPath))) {
	throw new Exception('The bootstrap/cache directory must be present and writable.');
	}
	$this->files->put(
	$this->manifestPath, '<?php return '.var_export($manifest, true).';'
	);
	return array_merge(['when' => []], $manifest);
	}

到这时，ProviderRepository::load() 的服务提供者缓存的判断和执行流程就结束了。我们回到 ProviderRepository::load() 的后面流程，接下来就是

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 64 to 69 in d081c91

	// Next, we will register events to load the providers for each of the events
	// that it has requested. This allows the service provider to defer itself
	// while still getting automatically loaded when a certain event occurs.
	foreach ($manifest['when'] as $provider => $events) {
	$this->registerLoadEvents($provider, $events);
	}

没错，触发 registerLoadEvents 方法了。感谢 laravel 代码做到了足够语义化，我们猜到了这里就是触发服务提供者注册事件的。具体流程为：

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 112 to 128 in d081c91

	/**
	* Register the load events for the given provider.
	*
	* @param string $provider
	* @param array $events
	* @return void
	*/
	protected function registerLoadEvents($provider, array $events)
	{
	if (count($events) < 1) {
	return;
	}
	$this->app->make('events')->listen($events, function () use ($provider) {
	$this->app->register($provider);
	});
	}

• 若需关注更多关于 Laravel 事件触发机制，请关注 [TODO]

再继续后面，就是 ProviderRepository::load() 触发容器的 register 的流程了

laravel/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php

Lines 71 to 76 in d081c91

	// We will go ahead and register all of the eagerly loaded providers with the
	// application so their services can be registered with the application as
	// a provided service. Then we will set the deferred service list on it.
	foreach ($manifest['eager'] as $provider) {
	$this->app->register($provider);
	}

Illuminate\Foundation\Container\Appplication 容器的 register 方法代码为

laravel/vendor/laravel/framework/src/Illuminate/Foundation/Application.php

Lines 551 to 600 in d081c91

	/**
	* Register a service provider with the application.
	*
	* @param \Illuminate\Support\ServiceProvider|string $provider
	* @param bool $force
	* @return \Illuminate\Support\ServiceProvider
	*/
	public function register($provider, $force = false)
	{
	if (($registered = $this->getProvider($provider)) && ! $force) {
	return $registered;
	}
	// If the given "provider" is a string, we will resolve it, passing in the
	// application instance automatically for the developer. This is simply
	// a more convenient way of specifying your service provider classes.
	if (is_string($provider)) {
	$provider = $this->resolveProvider($provider);
	}
	if (method_exists($provider, 'register')) {
	$provider->register();
	}
	// If there are bindings / singletons set as properties on the provider we
	// will spin through them and register them with the application, which
	// serves as a convenience layer while registering a lot of bindings.
	if (property_exists($provider, 'bindings')) {
	foreach ($provider->bindings as $key => $value) {
	$this->bind($key, $value);
	}
	}
	if (property_exists($provider, 'singletons')) {
	foreach ($provider->singletons as $key => $value) {
	$this->singleton($key, $value);
	}
	}
	$this->markAsRegistered($provider);
	// If the application has already booted, we will call this boot method on
	// the provider class so it has an opportunity to do its boot logic and
	// will be ready for any usage by this developer's application logic.
	if ($this->booted) {
	$this->bootProvider($provider);
	}
	return $provider;
	}

步骤

1. 先尝试取 getProvider 这个服务，如果能取到证明注册过了，除非要求强硬方式 $force 就不再注册
2. 解析出 $provier 为具体的 ServiceProvider 对象
3. 判断 $provider 有无 register 方法，有则运行
4. 判断 $provider有无定义 $bindings 属性，若有，则依次 $key，$value 为参，进入 Illuminate\Foundation\Container\Appplication::bind($key, $value) 执行
5. 判断 $provider 有无定义 $singletons 属性，若有，则依次 $key，$value 为参，进入 Illuminate\Foundation\Container\Appplication::singleton($key, $value) 执行
6. 标记这个服务提供者已被注册过了 Illuminate\Foundation\Container\Appplication::$loadedProviders[ServiceProvider::class] = true
7. 如果服务提供者已经被启动过了 ($booted == true), 调用 bootProvider($provider)