7 files changed, 515 insertions, 266 deletions
diff --git a/phpBB/phpbb/di/container_builder.php b/phpBB/phpbb/di/container_builder.php
index 99576f9020..433847b285 100644
--- a/phpBB/phpbb/di/container_builder.php
+++ b/phpBB/phpbb/di/container_builder.php
@@ -13,6 +13,7 @@
 
 namespace phpbb\di;
 
+use phpbb\filesystem\filesystem;
 use Symfony\Component\Config\ConfigCache;
 use Symfony\Component\Config\FileLocator;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
@@ -20,11 +21,18 @@ use Symfony\Component\DependencyInjection\Dumper\PhpDumper;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
 use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
 use Symfony\Component\EventDispatcher\DependencyInjection\RegisterListenersPass;
+use Symfony\Component\Filesystem\Exception\IOException;
+use Symfony\Component\Finder\Finder;
 use Symfony\Component\HttpKernel\DependencyInjection\MergeExtensionConfigurationPass;
 
 class container_builder
 {
 	/**
+	 * @var string The environment to use.
+	 */
+	protected $environment;
+
+	/**
 	 * @var string phpBB Root Path
 	 */
 	protected $phpbb_root_path;
@@ -35,89 +43,58 @@ class container_builder
 	protected $php_ext;
 
 	/**
-	* The container under construction
-	*
-	* @var ContainerBuilder
-	*/
+	 * The container under construction
+	 *
+	 * @var ContainerBuilder
+	 */
 	protected $container;
 
 	/**
-	* @var \phpbb\db\driver\driver_interface
-	*/
-	protected $dbal_connection = null;
-
-	/**
-	* @var array the installed extensions
-	*/
-	protected $installed_exts = null;
-
-	/**
-	* Indicates whether the php config file should be injected into the container (default to true).
-	*
-	* @var bool
-	*/
-	protected $inject_config = true;
-
-	/**
-	* Indicates whether extensions should be used (default to true).
-	*
-	* @var bool
-	*/
+	 * Indicates whether extensions should be used (default to true).
+	 *
+	 * @var bool
+	 */
 	protected $use_extensions = true;
 
 	/**
-	* Defines a custom path to find the configuration of the container (default to $this->phpbb_root_path . 'config')
-	*
-	* @var string
-	*/
+	 * Defines a custom path to find the configuration of the container (default to $this->phpbb_root_path . 'config')
+	 *
+	 * @var string
+	 */
 	protected $config_path = null;
 
 	/**
-	* Indicates whether the phpBB compile pass should be used (default to true).
-	*
-	* @var bool
-	*/
-	protected $use_custom_pass = true;
-
-	/**
-	* Indicates whether the kernel compile pass should be used (default to true).
-	*
-	* @var bool
-	*/
-	protected $use_kernel_pass = true;
-
-	/**
-	* Indicates whether the container should be dumped to the filesystem (default to true).
-	*
-	* If DEBUG_CONTAINER is set this option is ignored and a new container is build.
-	*
-	* @var bool
-	*/
-	protected $dump_container = true;
+	 * Indicates whether the container should be dumped to the filesystem (default to true).
+	 *
+	 * If DEBUG_CONTAINER is set this option is ignored and a new container is build.
+	 *
+	 * @var bool
+	 */
+	protected $use_cache = true;
 
 	/**
-	* Indicates if the container should be compiled automatically (default to true).
-	*
-	* @var bool
-	*/
+	 * Indicates if the container should be compiled automatically (default to true).
+	 *
+	 * @var bool
+	 */
 	protected $compile_container = true;
 
 	/**
-	* Custom parameters to inject into the container.
-	*
-	* Default to true:
-	* 	array(
-	* 		'core.root_path', $this->phpbb_root_path,
-	* 		'core.php_ext', $this->php_ext,
-	* );
-	*
-	* @var array
-	*/
-	protected $custom_parameters = null;
+	 * Custom parameters to inject into the container.
+	 *
+	 * Default to:
+	 * 	array(
+	 * 		'core.root_path', $this->phpbb_root_path,
+	 * 		'core.php_ext', $this->php_ext,
+	 * );
+	 *
+	 * @var array
+	 */
+	protected $custom_parameters = [];
 
 	/**
-	* @var \phpbb\config_php_file
-	*/
+	 * @var \phpbb\config_php_file
+	 */
 	protected $config_php_file;
 
 	/**
@@ -126,199 +103,271 @@ class container_builder
 	protected $cache_dir;
 
 	/**
-	* Constructor
-	*
-	* @param \phpbb\config_php_file $config_php_file
-	* @param string $phpbb_root_path Path to the phpbb includes directory.
-	* @param string $php_ext php file extension
-	*/
-	function __construct(\phpbb\config_php_file $config_php_file, $phpbb_root_path, $php_ext)
+	 * @var array
+	 */
+	private $container_extensions;
+
+	/** @var \Exception */
+	private $build_exception;
+
+	/**
+	 * Constructor
+	 *
+	 * @param string $phpbb_root_path Path to the phpbb includes directory.
+	 * @param string $php_ext php file extension
+	 */
+	public function __construct($phpbb_root_path, $php_ext)
 	{
-		$this->config_php_file = $config_php_file;
 		$this->phpbb_root_path = $phpbb_root_path;
 		$this->php_ext = $php_ext;
 	}
 
 	/**
-	* Build and return a new Container respecting the current configuration
-	*
-	* @return \phpbb_cache_container|ContainerBuilder
-	*/
+	 * Build and return a new Container respecting the current configuration
+	 *
+	 * @return \phpbb_cache_container|ContainerBuilder
+	 */
 	public function get_container()
 	{
-		$container_filename = $this->get_container_filename();
-		$config_cache = new ConfigCache($container_filename, defined('DEBUG'));
-		if ($this->dump_container && $config_cache->isFresh())
+		try
 		{
-			require($config_cache->getPath());
-			$this->container = new \phpbb_cache_container();
-		}
-		else
-		{
-			$container_extensions = array(new \phpbb\di\extension\core($this->get_config_path()));
-
-			if ($this->use_extensions)
+			$container_filename = $this->get_container_filename();
+			$config_cache = new ConfigCache($container_filename, defined('DEBUG'));
+			if ($this->use_cache && $config_cache->isFresh())
 			{
-				$installed_exts = $this->get_installed_extensions();
-				foreach ($installed_exts as $ext_name => $path)
-				{
-					$extension_class = '\\' . str_replace('/', '\\', $ext_name) . '\\di\\extension';
+				require($config_cache->getPath());
+				$this->container = new \phpbb_cache_container();
+			}
+			else
+			{
+				$this->container_extensions = array(new extension\core($this->get_config_path()));
 
-					if (!class_exists($extension_class))
-					{
-						$extension_class = '\phpbb\extension\di\extension_base';
-					}
+				if ($this->use_extensions)
+				{
+					$this->load_extensions();
+				}
 
-					$container_extensions[] = new $extension_class($ext_name, $path);
+				// Inject the config
+				if ($this->config_php_file)
+				{
+					$this->container_extensions[] = new extension\config($this->config_php_file);
 				}
-			}
 
-			if ($this->inject_config)
-			{
-				$container_extensions[] = new \phpbb\di\extension\config($this->config_php_file);
-			}
+				$this->container = $this->create_container($this->container_extensions);
 
-			$this->container = $this->create_container($container_extensions);
+				// Easy collections through tags
+				$this->container->addCompilerPass(new pass\collection_pass());
 
-			if ($this->use_custom_pass)
-			{
-				// Symfony Kernel Listeners
-				$this->container->addCompilerPass(new \phpbb\di\pass\collection_pass());
+				// Event listeners "phpBB style"
 				$this->container->addCompilerPass(new RegisterListenersPass('dispatcher', 'event.listener_listener', 'event.listener'));
 
-				if ($this->use_kernel_pass)
+				// Event listeners "Symfony style"
+				$this->container->addCompilerPass(new RegisterListenersPass('dispatcher'));
+
+				if ($this->use_extensions)
 				{
-					$this->container->addCompilerPass(new RegisterListenersPass('dispatcher'));
+					$this->register_ext_compiler_pass();
 				}
-			}
 
-			$filesystem = new \phpbb\filesystem\filesystem();
-			$loader = new YamlFileLoader($this->container, new FileLocator($filesystem->realpath($this->get_config_path())));
-			$loader->load($this->container->getParameter('core.environment') . '/config.yml');
+				$filesystem = new filesystem();
+				$loader     = new YamlFileLoader($this->container, new FileLocator($filesystem->realpath($this->get_config_path())));
+				$loader->load($this->container->getParameter('core.environment') . '/config.yml');
+
+				$this->inject_custom_parameters();
+
+				if ($this->compile_container)
+				{
+					$this->container->compile();
 
-			$this->inject_custom_parameters();
+					if ($this->use_cache)
+					{
+						$this->dump_container($config_cache);
+					}
+				}
+			}
 
-			if ($this->compile_container)
+			if ($this->compile_container && $this->config_php_file)
 			{
-				$this->container->compile();
+				$this->container->set('config.php', $this->config_php_file);
 			}
 
-			if ($this->dump_container)
+			return $this->container;
+		}
+		catch (\Exception $e)
+		{
+			// Don't try to recover if we are in the development environment
+			if ($this->get_environment() === 'development')
+			{
+				throw $e;
+			}
+
+			if ($this->build_exception === null)
 			{
-				$this->dump_container($config_cache);
+				$this->build_exception = $e;
+
+				return $this
+					->without_extensions()
+					->without_cache()
+					->with_custom_parameters(array_merge($this->custom_parameters, [
+						'container_exception' => $e,
+					]))
+					->get_container();
+			}
+			else
+			{
+				// Rethrow the original exception if it's still failing
+				throw $this->build_exception;
 			}
 		}
+	}
+
+	/**
+	 * Enable the extensions.
+	 *
+	 * @param string $environment The environment to use
+	 * @return $this
+	 */
+	public function with_environment($environment)
+	{
+		$this->environment = $environment;
 
-		$this->container->set('config.php', $this->config_php_file);
+		return $this;
+	}
 
-		if ($this->compile_container)
-		{
-			$this->inject_dbal();
-		}
+	/**
+	 * Enable the extensions.
+	 *
+	 * @return $this
+	 */
+	public function with_extensions()
+	{
+		$this->use_extensions = true;
 
-		return $this->container;
+		return $this;
 	}
 
 	/**
-	* Set if the extensions should be used.
-	*
-	* @param bool $use_extensions
-	*/
-	public function set_use_extensions($use_extensions)
+	 * Disable the extensions.
+	 *
+	 * @return $this
+	 */
+	public function without_extensions()
 	{
-		$this->use_extensions = $use_extensions;
+		$this->use_extensions = false;
+
+		return $this;
 	}
 
 	/**
-	* Set if the phpBB compile pass have to be used.
-	*
-	* @param bool $use_custom_pass
-	*/
-	public function set_use_custom_pass($use_custom_pass)
+	 * Enable the caching of the container.
+	 *
+	 * If DEBUG_CONTAINER is set this option is ignored and a new container is build.
+	 *
+	 * @return $this
+	 */
+	public function with_cache()
 	{
-		$this->use_custom_pass = $use_custom_pass;
+		$this->use_cache = true;
+
+		return $this;
 	}
 
 	/**
-	* Set if the kernel compile pass have to be used.
-	*
-	* @param bool $use_kernel_pass
-	*/
-	public function set_use_kernel_pass($use_kernel_pass)
+	 * Disable the caching of the container.
+	 *
+	 * @return $this
+	 */
+	public function without_cache()
 	{
-		$this->use_kernel_pass = $use_kernel_pass;
+		$this->use_cache = false;
+
+		return $this;
 	}
 
 	/**
-	* Set if the php config file should be injecting into the container.
-	*
-	* @param bool $inject_config
-	*/
-	public function set_inject_config($inject_config)
+	 * Set the cache directory.
+	 *
+	 * @param string $cache_dir The cache directory.
+	 * @return $this
+	 */
+	public function with_cache_dir($cache_dir)
 	{
-		$this->inject_config = $inject_config;
+		$this->cache_dir = $cache_dir;
+
+		return $this;
 	}
 
 	/**
-	* Set if a dump container should be used.
-	*
-	* If DEBUG_CONTAINER is set this option is ignored and a new container is build.
-	*
-	* @var bool $dump_container
-	*/
-	public function set_dump_container($dump_container)
+	 * Enable the compilation of the container.
+	 *
+	 * @return $this
+	 */
+	public function with_compiled_container()
 	{
-		$this->dump_container = $dump_container;
+		$this->compile_container = true;
+
+		return $this;
 	}
 
 	/**
-	* Set if the container should be compiled automatically (default to true).
-	*
-	* @var bool $dump_container
-	*/
-	public function set_compile_container($compile_container)
+	 * Disable the compilation of the container.
+	 *
+	 * @return $this
+	 */
+	public function without_compiled_container()
 	{
-		$this->compile_container = $compile_container;
+		$this->compile_container = false;
+
+		return $this;
 	}
 
 	/**
-	* Set a custom path to find the configuration of the container
-	*
-	* @param string $config_path
-	*/
-	public function set_config_path($config_path)
+	 * Set a custom path to find the configuration of the container.
+	 *
+	 * @param string $config_path
+	 * @return $this
+	 */
+	public function with_config_path($config_path)
 	{
 		$this->config_path = $config_path;
+
+		return $this;
 	}
 
 	/**
-	 * Returns the path to the container configuration (default: root_path/config)
+	 * Set custom parameters to inject into the container.
 	 *
-	 * @return string
+	 * @param array $custom_parameters
+	 * @return $this
 	 */
-	protected function get_config_path()
+	public function with_custom_parameters($custom_parameters)
 	{
-		return $this->config_path ?: $this->phpbb_root_path . 'config';
+		$this->custom_parameters = $custom_parameters;
+
+		return $this;
 	}
 
 	/**
-	* Set custom parameters to inject into the container.
-	*
-	* @param array $custom_parameters
-	*/
-	public function set_custom_parameters($custom_parameters)
+	 * Set custom parameters to inject into the container.
+	 *
+	 * @param \phpbb\config_php_file $config_php_file
+	 * @return $this
+	 */
+	public function with_config(\phpbb\config_php_file $config_php_file)
 	{
-		$this->custom_parameters = $custom_parameters;
+		$this->config_php_file = $config_php_file;
+
+		return $this;
 	}
 
 	/**
-	 * Set the path to the cache directory.
+	 * Returns the path to the container configuration (default: root_path/config)
 	 *
-	 * @param string $cache_dir Path to the cache directory
+	 * @return string
 	 */
-	public function set_cache_dir($cache_dir)
+	protected function get_config_path()
 	{
-		$this->cache_dir = $cache_dir;
+		return $this->config_path ?: $this->phpbb_root_path . 'config';
 	}
 
 	/**
@@ -332,89 +381,86 @@ class container_builder
 	}
 
 	/**
-	* Dump the container to the disk.
-	*
-	* @param ConfigCache $cache The config cache
-	*/
-	protected function dump_container($cache)
+	 * Load the enabled extensions.
+	 */
+	protected function load_extensions()
 	{
-		$dumper = new PhpDumper($this->container);
-		$cached_container_dump = $dumper->dump(array(
-			'class'         => 'phpbb_cache_container',
-			'base_class'    => 'Symfony\\Component\\DependencyInjection\\ContainerBuilder',
-		));
+		if ($this->config_php_file !== null)
+		{
+			// Build an intermediate container to load the ext list from the database
+			$container_builder = new container_builder($this->phpbb_root_path, $this->php_ext);
+			$ext_container = $container_builder
+				->without_cache()
+				->without_extensions()
+				->with_config($this->config_php_file)
+				->with_config_path($this->get_config_path())
+				->with_environment('production')
+				->without_compiled_container()
+				->get_container()
+			;
+
+			$ext_container->register('cache.driver', '\\phpbb\\cache\\driver\\dummy');
+			$ext_container->compile();
+
+			$extensions = $ext_container->get('ext.manager')->all_enabled();
+
+			// Load each extension found
+			foreach ($extensions as $ext_name => $path)
+			{
+				$extension_class = '\\' . str_replace('/', '\\', $ext_name) . '\\di\\extension';
 
-		$cache->write($cached_container_dump, $this->container->getResources());
-	}
+				if (!class_exists($extension_class))
+				{
+					$extension_class = '\\phpbb\\extension\\di\\extension_base';
+				}
 
-	/**
-	* Inject the connection into the container if one was opened.
-	*/
-	protected function inject_dbal()
-	{
-		if ($this->dbal_connection !== null)
-		{
-			$this->container->get('dbal.conn')->set_driver($this->dbal_connection);
-		}
-	}
+				$this->container_extensions[] = new $extension_class($ext_name, $path);
 
-	/**
-	* Get DB connection.
-	*
-	* @return \phpbb\db\driver\driver_interface
-	*/
-	protected function get_dbal_connection()
-	{
-		if ($this->dbal_connection === null)
+				// Load extension autoloader
+				$filename = $path . 'vendor/autoload.php';
+				if (file_exists($filename))
+				{
+					require $filename;
+				}
+			}
+		}
+		else
 		{
-			$dbal_driver_class = $this->config_php_file->convert_30_dbms_to_31($this->config_php_file->get('dbms'));
-			$this->dbal_connection = new $dbal_driver_class();
-			$this->dbal_connection->sql_connect(
-				$this->config_php_file->get('dbhost'),
-				$this->config_php_file->get('dbuser'),
-				$this->config_php_file->get('dbpasswd'),
-				$this->config_php_file->get('dbname'),
-				$this->config_php_file->get('dbport'),
-				defined('PHPBB_DB_NEW_LINK') && PHPBB_DB_NEW_LINK
-			);
+			// To load the extensions we need the database credentials.
+			// Automatically disable the extensions if we don't have them.
+			$this->use_extensions = false;
 		}
-
-		return $this->dbal_connection;
 	}
 
 	/**
-	* Get enabled extensions.
-	*
-	* @return array enabled extensions
-	*/
-	protected function get_installed_extensions()
+	 * Dump the container to the disk.
+	 *
+	 * @param ConfigCache $cache The config cache
+	 */
+	protected function dump_container($cache)
 	{
-		$db = $this->get_dbal_connection();
-		$extension_table = $this->config_php_file->get('table_prefix') . 'ext';
-
-		$sql = 'SELECT *
-			FROM ' . $extension_table . '
-			WHERE ext_active = 1';
-
-		$result = $db->sql_query($sql);
-		$rows = $db->sql_fetchrowset($result);
-		$db->sql_freeresult($result);
+		try
+		{
+			$dumper                = new PhpDumper($this->container);
+			$cached_container_dump = $dumper->dump(array(
+				'class'      => 'phpbb_cache_container',
+				'base_class' => 'Symfony\\Component\\DependencyInjection\\ContainerBuilder',
+			));
 
-		$exts = array();
-		foreach ($rows as $row)
+			$cache->write($cached_container_dump, $this->container->getResources());
+		}
+		catch (IOException $e)
 		{
-			$exts[$row['ext_name']] = $this->phpbb_root_path . 'ext/' . $row['ext_name'] . '/';
+			// Don't fail if the cache isn't writeable
 		}
-
-		return $exts;
 	}
 
 	/**
-	* Create the ContainerBuilder object
-	*
-	* @param array $extensions Array of Container extension objects
-	* @return ContainerBuilder object
-	*/
+	 * Create the ContainerBuilder object
+	 *
+	 * @param array $extensions Array of Container extension objects
+	 * @return ContainerBuilder object
+	 */
 	protected function create_container(array $extensions)
 	{
 		$container = new ContainerBuilder(new ParameterBag($this->get_core_parameters()));
@@ -425,7 +471,6 @@ class container_builder
 		{
 			$container->registerExtension($extension);
 			$extensions_alias[] = $extension->getAlias();
-			//$container->loadFromExtension($extension->getAlias());
 		}
 
 		$container->getCompilerPassConfig()->setMergePass(new MergeExtensionConfigurationPass($extensions_alias));
@@ -438,13 +483,11 @@ class container_builder
 	 */
 	protected function inject_custom_parameters()
 	{
-		if ($this->custom_parameters !== null)
+		foreach ($this->custom_parameters as $key => $value)
 		{
-			foreach ($this->custom_parameters as $key => $value)
-			{
-				$this->container->setParameter($key, $value);
-			}
+			$this->container->setParameter($key, $value);
 		}
+
 	}
 
 	/**
@@ -459,7 +502,7 @@ class container_builder
 				'core.root_path'     => $this->phpbb_root_path,
 				'core.php_ext'       => $this->php_ext,
 				'core.environment'   => $this->get_environment(),
-				'core.debug'         => DEBUG,
+				'core.debug'         => defined('DEBUG') ? DEBUG : false,
 			),
 			$this->get_env_parameters()
 		);
@@ -487,14 +530,13 @@ class container_builder
 	}
 
 	/**
-	* Get the filename under which the dumped container will be stored.
-	*
-	* @return string Path for dumped container
-	*/
+	 * Get the filename under which the dumped container will be stored.
+	 *
+	 * @return string Path for dumped container
+	 */
 	protected function get_container_filename()
 	{
-		$filename = str_replace(array('/', '.'), array('slash', 'dot'), $this->phpbb_root_path);
-		return $this->get_cache_dir() . 'container_' . $filename . '.' . $this->php_ext;
+		return $this->get_cache_dir() . 'container_' . md5($this->phpbb_root_path) . '.' . $this->php_ext;
 	}
 
 	/**
@@ -504,6 +546,36 @@ class container_builder
 	 */
 	protected function get_environment()
 	{
-		return PHPBB_ENVIRONMENT;
+		return $this->environment ?: PHPBB_ENVIRONMENT;
+	}
+
+	private function register_ext_compiler_pass()
+	{
+		$finder = new Finder();
+		$finder
+			->name('*_pass.php')
+			->path('di/pass')
+			->files()
+			->ignoreDotFiles(true)
+			->ignoreUnreadableDirs(true)
+			->ignoreVCS(true)
+			->followLinks()
+			->in($this->phpbb_root_path . 'ext/')
+		;
+
+		/** @var \SplFileInfo $pass */
+		foreach ($finder as $pass)
+		{
+			$filename = $pass->getPathname();
+			$filename = substr($filename, 0, -strlen('.' . $pass->getExtension()));
+			$filename = str_replace(DIRECTORY_SEPARATOR, '/', $filename);
+			$className = preg_replace('#^.*ext/#', '', $filename);
+			$className = '\\' . str_replace('/', '\\', $className);
+
+			if (class_exists($className) && in_array('Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface', class_implements($className), true))
+			{
+				$this->container->addCompilerPass(new $className());
+			}
+		}
 	}
 }
diff --git a/phpBB/phpbb/di/extension/container_configuration.php b/phpBB/phpbb/di/extension/container_configuration.php
index 4cc7c7c0d1..4585d6509e 100644
--- a/phpBB/phpbb/di/extension/container_configuration.php
+++ b/phpBB/phpbb/di/extension/container_configuration.php
@@ -31,6 +31,12 @@ class container_configuration implements ConfigurationInterface
 		$rootNode
 			->children()
 				->booleanNode('require_dev_dependencies')->defaultValue(false)->end()
+				->arrayNode('debug')
+					->addDefaultsIfNotSet()
+					->children()
+						->booleanNode('exceptions')->defaultValue(false)->end()
+					->end()
+				->end()
 				->arrayNode('twig')
 					->addDefaultsIfNotSet()
 					->children()
diff --git a/phpBB/phpbb/di/extension/core.php b/phpBB/phpbb/di/extension/core.php
index 91b321a684..c48a80a558 100644
--- a/phpBB/phpbb/di/extension/core.php
+++ b/phpBB/phpbb/di/extension/core.php
@@ -80,6 +80,7 @@ class core extends Extension
 		{
 			$twig_environment_options['auto_reload'] = true;
 		}
+
 		// Replace the 8th argument, the options passed to the environment
 		$definition->replaceArgument(7, $twig_environment_options);
 
@@ -88,6 +89,12 @@ class core extends Extension
 			$definition = $container->getDefinition('template.twig.extensions.debug');
 			$definition->addTag('twig.extension');
 		}
+
+		// Set the debug options
+		foreach ($config['debug'] as $name => $value)
+		{
+			$container->setParameter('debug.' . $name, $value);
+		}
 	}
 
 	/**
diff --git a/phpBB/phpbb/di/ordered_service_collection.php b/phpBB/phpbb/di/ordered_service_collection.php
new file mode 100644
index 0000000000..046012ae5b
--- /dev/null
+++ b/phpBB/phpbb/di/ordered_service_collection.php
@@ -0,0 +1,117 @@
+<?php
+/**
+ *
+ * This file is part of the phpBB Forum Software package.
+ *
+ * @copyright (c) phpBB Limited <https://www.phpbb.com>
+ * @license GNU General Public License, version 2 (GPL-2.0)
+ *
+ * For full copyright and license information, please see
+ * the docs/CREDITS.txt file.
+ *
+ */
+
+namespace phpbb\di;
+
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Collection of services in a specified order
+ */
+class ordered_service_collection extends service_collection
+{
+	/**
+	 * @var bool
+	 */
+	protected $is_ordered;
+
+	/**
+	 * @var array
+	 */
+	protected $service_ids;
+
+	/**
+	 * Constructor
+	 *
+	 * @param ContainerInterface $container Container object
+	 */
+	public function __construct(ContainerInterface $container)
+	{
+		$this->is_ordered = false;
+		$this->service_ids = array();
+
+		parent::__construct($container);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function getIterator()
+	{
+		if (!$this->is_ordered)
+		{
+			$this->sort_services();
+		}
+
+		return new service_collection_iterator($this);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function offsetExists($index)
+	{
+		if (!$this->is_ordered)
+		{
+			$this->sort_services();
+		}
+
+		return parent::offsetExists($index);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function offsetGet($index)
+	{
+		if (!$this->is_ordered)
+		{
+			$this->sort_services();
+		}
+
+		return parent::offsetGet($index);
+	}
+
+	/**
+	 * Adds a service ID to the collection
+	 *
+	 * @param string	$service_id
+	 * @param int		$order
+	 */
+	public function add($service_id, $order = 0)
+	{
+		$order = (int) $order;
+		$this->service_ids[$order][] = $service_id;
+		$this->is_ordered = false;
+	}
+
+	protected function sort_services()
+	{
+		if ($this->is_ordered)
+		{
+			return;
+		}
+
+		$this->exchangeArray(array());
+		ksort($this->service_ids);
+		foreach ($this->service_ids as $service_order_group)
+		{
+			foreach ($service_order_group as $service_id)
+			{
+				$this->offsetSet($service_id, null);
+			}
+		}
+
+		$this->is_ordered = true;
+	}
+}
diff --git a/phpBB/phpbb/di/pass/collection_pass.php b/phpBB/phpbb/di/pass/collection_pass.php
index a5c054674e..341f88518d 100644
--- a/phpBB/phpbb/di/pass/collection_pass.php
+++ b/phpBB/phpbb/di/pass/collection_pass.php
@@ -34,10 +34,30 @@ class collection_pass implements CompilerPassInterface
 		foreach ($container->findTaggedServiceIds('service_collection') as $id => $data)
 		{
 			$definition = $container->getDefinition($id);
+			$is_ordered_collection = (substr($definition->getClass(), -strlen('ordered_service_collection')) === 'ordered_service_collection');
+			$is_class_name_aware = (isset($data[0]['class_name_aware']) && $data[0]['class_name_aware']);
 
 			foreach ($container->findTaggedServiceIds($data[0]['tag']) as $service_id => $service_data)
 			{
-				$definition->addMethodCall('add', array($service_id));
+				if ($is_ordered_collection)
+				{
+					$arguments = array($service_id, $service_data[0]['order']);
+				}
+				else
+				{
+					$arguments = array($service_id);
+				}
+
+				if ($is_class_name_aware)
+				{
+					$service_definition = $container->getDefinition($service_id);
+					$definition->addMethodCall('add_service_class', array(
+						$service_id,
+						$service_definition->getClass()
+					));
+				}
+
+				$definition->addMethodCall('add', $arguments);
 			}
 		}
 	}
diff --git a/phpBB/phpbb/di/service_collection.php b/phpBB/phpbb/di/service_collection.php
index 82ca9bf679..8e9175e204 100644
--- a/phpBB/phpbb/di/service_collection.php
+++ b/phpBB/phpbb/di/service_collection.php
@@ -26,6 +26,11 @@ class service_collection extends \ArrayObject
 	protected $container;
 
 	/**
+	* @var array
+	*/
+	protected $service_classes;
+
+	/**
 	* Constructor
 	*
 	* @param ContainerInterface $container Container object
@@ -33,6 +38,7 @@ class service_collection extends \ArrayObject
 	public function __construct(ContainerInterface $container)
 	{
 		$this->container = $container;
+		$this->service_classes = array();
 	}
 
 	/**
@@ -76,4 +82,25 @@ class service_collection extends \ArrayObject
 	{
 		$this->offsetSet($name, null);
 	}
+
+	/**
+	* Add a service's class to the collection
+	*
+	* @param string	$service_id
+	* @param string	$class
+	*/
+	public function add_service_class($service_id, $class)
+	{
+		$this->service_classes[$service_id] = $class;
+	}
+
+	/**
+	* Get services' classes
+	*
+	* @return array
+	*/
+	public function get_service_classes()
+	{
+		return $this->service_classes;
+	}
 }
diff --git a/phpBB/phpbb/di/service_collection_iterator.php b/phpBB/phpbb/di/service_collection_iterator.php
index 0d031ab52d..31bc156e99 100644
--- a/phpBB/phpbb/di/service_collection_iterator.php
+++ b/phpBB/phpbb/di/service_collection_iterator.php
@@ -32,7 +32,7 @@ class service_collection_iterator extends \ArrayIterator
 	*/
 	public function __construct(service_collection $collection, $flags = 0)
 	{
-		parent::__construct($collection, $flags);
+		parent::__construct($collection->getArrayCopy(), $flags);
 		$this->collection = $collection;
 	}