<?php
namespace Illuminate\Foundation;
use Exception;
use Illuminate\Contracts\Foundation\Application as ApplicationContract;
use Illuminate\Filesystem\Filesystem;
class ProviderRepository
{
/**
* The application implementation.
*
* @var \Illuminate\Contracts\Foundation\Application
*/
protected $app;
/**
* The filesystem instance.
*
* @var \Illuminate\Filesystem\Filesystem
*/
protected $files;
/**
* The path to the manifest file.
*
* @var string
*/
protected $manifestPath;
/**
* Create a new service repository instance.
*
* @param \Illuminate\Contracts\Foundation\Application $app
* @param \Illuminate\Filesystem\Filesystem $files
* @param string $manifestPath
* @return void
*/
public function __construct(ApplicationContract $app, Filesystem $files, $manifestPath)
{
$this->app = $app;
$this->files = $files;
$this->manifestPath = $manifestPath;
}
/**
* 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']);
}
/**
* 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);
}
}
}
/**
* 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;
}
/**
* 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);
});
}
/**
* 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);
}
/**
* Create a fresh service manifest data structure.
*
* @param array $providers
* @return array
*/
protected function freshManifest(array $providers)
{
return ['providers' => $providers, 'eager' => [], 'deferred' => []];
}
/**
* Write the service manifest file to disk.
*
* @param array $manifest
* @return array
*
* @throws \Exception
*/
public function writeManifest($manifest)
{
if (! is_writable($dirname = dirname($this->manifestPath))) {
throw new Exception("The {$dirname} directory must be present and writable.");
}
$this->files->replace(
$this->manifestPath, '<?php return '.var_export($manifest, true).';'
);
return array_merge(['when' => []], $manifest);
}
/**
* Create a new provider instance.
*
* @param string $provider
* @return \Illuminate\Support\ServiceProvider
*/
public function createProvider($provider)
{
return new $provider($this->app);
}
}