[Config] Delegate creation of ConfigCache instances to a factory.

UPGRADE-2.7.md

@@ -16,6 +16,12 @@ Router
    but in 2.7 you would get an error if `bar` parameter
    doesn't exist or unexpected result otherwise.
 
+ * The `getMatcherDumperInstance()` and `getGeneratorDumperInstance()` methods in the
+   `Symfony\Component\Routing\Router` have been changed from `protected` to `public`.
+   If you override these methods in a subclass, you will need to change your 
+   methods to `public` as well. Note however that this is a temporary change needed for
+   PHP 5.3 compatibility only. It will be reverted in Symfony 3.0.
+ 
 Form
 ----
 
@@ -515,3 +521,10 @@ PropertyAccess
 
         new UnexpectedTypeException($value, $path, $pathIndex);
    ```
+
+Config
+------
+
+ * The `__toString()` method of the `\Symfony\Component\Config\ConfigCache` is marked as 
+   deprecated in favor of the new `getPath()` method.
+   

src/Symfony/Component/Config/CHANGELOG.md

@@ -1,6 +1,12 @@
 CHANGELOG
 =========
 
+2.7.0
+-----
+
+ * added `ConfigCacheInterface`, `ConfigCacheFactoryInterface` and a basic `ConfigCacheFactory`
+   implementation to delegate creation of ConfigCache instances
+   
 2.2.0
 -----
 

src/Symfony/Component/Config/ConfigCache.php

@@ -23,14 +23,12 @@ use Symfony\Component\Filesystem\Filesystem;
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class ConfigCache
+class ConfigCache implements ConfigCacheInterface
 {
     private $debug;
     private $file;
 
     /**
-     * Constructor.
-     *
      * @param string $file  The absolute cache path
      * @param bool   $debug Whether debugging is enabled or not
      */
@@ -44,8 +42,21 @@ class ConfigCache
      * Gets the cache file path.
      *
      * @return string The cache file path
+     * @deprecated since 2.7, to be removed in 3.0. Use getPath() instead.
      */
     public function __toString()
+    {
+        trigger_error('ConfigCache::__toString() is deprecated since version 2.7 and will be removed in 3.0. Use the getPath() method instead.', E_USER_DEPRECATED);
+
+        return $this->file;
+    }
+
+    /**
+     * Gets the cache file path.
+     *
+     * @return string The cache file path
+     */
+    public function getPath()
     {
         return $this->file;
     }

src/Symfony/Component/Config/ConfigCacheFactory.php

@@ -0,0 +1,48 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Config;
+
+/**
+ * Basic implementation for ConfigCacheFactoryInterface
+ * that will simply create an instance of ConfigCache.
+ *
+ * @author Matthias Pigulla <mp@webfactory.de>
+ */
+class ConfigCacheFactory implements ConfigCacheFactoryInterface
+{
+    /**
+     * @var bool Debug flag passed to the ConfigCache
+     */
+    private $debug;
+
+    /**
+     * @param bool $debug The debug flag to pass to ConfigCache
+     */
+    public function __construct($debug)
+    {
+        $this->debug = $debug;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function cache($file, $callback)
+    {
+        $cache = new ConfigCache($file, $this->debug);
+
+        if (!$cache->isFresh()) {
+            call_user_func($callback, $cache);
+        }
+
+        return $cache;
+    }
+}

src/Symfony/Component/Config/ConfigCacheFactoryInterface.php

@@ -0,0 +1,32 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Config;
+
+/**
+ * Interface for a ConfigCache factory. This factory creates
+ * an instance of ConfigCacheInterface and initializes the
+ * cache if necessary.
+ *
+ * @author Matthias Pigulla <mp@webfactory.de>
+ */
+interface ConfigCacheFactoryInterface
+{
+    /**
+     * Creates a cache instance and (re-)initializes it if necessary.
+     *
+     * @param  string               $file        The absolute cache file path
+     * @param  callable             $callable    The callable to be executed when the cache needs to be filled (i. e. is not fresh). The cache will be passed as the only parameter to this callback
+     *
+     * @return ConfigCacheInterface $configCache The cache instance
+     */
+    public function cache($file, $callable);
+}

src/Symfony/Component/Config/ConfigCacheInterface.php

@@ -0,0 +1,49 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Config;
+
+use Symfony\Component\Config\Resource\ResourceInterface;
+
+/**
+ * Interface for ConfigCache
+ *
+ * @author Matthias Pigulla <mp@webfactory.de>
+ */
+interface ConfigCacheInterface
+{
+    /**
+     * Gets the cache file path.
+     *
+     * @return string The cache file path
+     */
+    public function getPath();
+
+    /**
+     * Checks if the cache is still fresh.
+     *
+     * This check should take the metadata passed to the write() method into consideration.
+     *
+     * @return bool Whether the cache is still fresh.
+     */
+    public function isFresh();
+
+    /**
+     * Writes the given content into the cache file. Metadata will be stored
+     * independently and can be used to check cache freshness at a later time.
+     *
+     * @param string                   $content  The content to write into the cache
+     * @param ResourceInterface[]|null $metadata An array of ResourceInterface instances
+     *
+     * @throws \RuntimeException When the cache file cannot be written
+     */
+    public function write($content, array $metadata = null);
+}

src/Symfony/Component/Config/Tests/ConfigCacheTest.php

@@ -47,7 +47,7 @@ class ConfigCacheTest extends \PHPUnit_Framework_TestCase
     {
         $cache = new ConfigCache($this->cacheFile, true);
 
-        $this->assertSame($this->cacheFile, (string) $cache);
+        $this->assertSame($this->cacheFile, $cache->getPath());
     }
 
     public function testCacheIsNotFreshIfFileDoesNotExist()

src/Symfony/Component/HttpKernel/Kernel.php

@@ -252,7 +252,7 @@ abstract class Kernel implements KernelInterface, TerminableInterface
     }
 
     /**
-     * {@inheritDoc}
+     * {@inheritdoc}
      *
      * @throws \RuntimeException if a custom resource is hidden by a resource in a derived bundle
      */
@@ -546,7 +546,7 @@ abstract class Kernel implements KernelInterface, TerminableInterface
             $fresh = false;
         }
 
-        require_once $cache;
+        require_once $cache->getPath();
 
         $this->container = new $class();
         $this->container->set('kernel', $this);
@@ -695,7 +695,7 @@ abstract class Kernel implements KernelInterface, TerminableInterface
             $dumper->setProxyDumper(new ProxyDumper());
         }
 
-        $content = $dumper->dump(array('class' => $class, 'base_class' => $baseClass, 'file' => (string) $cache));
+        $content = $dumper->dump(array('class' => $class, 'base_class' => $baseClass, 'file' => $cache->getPath()));
         if (!$this->debug) {
             $content = static::stripComments($content);
         }

src/Symfony/Component/HttpKernel/composer.json

@@ -26,7 +26,7 @@
         "symfony/phpunit-bridge": "~2.7|~3.0.0",
         "symfony/browser-kit": "~2.3|~3.0.0",
         "symfony/class-loader": "~2.1|~3.0.0",
-        "symfony/config": "~2.0,>=2.0.5|~3.0.0",
+        "symfony/config": "~2.7",
         "symfony/console": "~2.3|~3.0.0",
         "symfony/css-selector": "~2.0,>=2.0.5|~3.0.0",
         "symfony/dependency-injection": "~2.2|~3.0.0",
@@ -40,6 +40,9 @@
         "symfony/translation": "~2.0,>=2.0.5|~3.0.0",
         "symfony/var-dumper": "~2.6|~3.0.0"
     },
+    "conflict": {
+        "symfony/config": "<2.7"
+    },
     "suggest": {
         "symfony/browser-kit": "",
         "symfony/class-loader": "",

src/Symfony/Component/Routing/Router.php

@@ -12,7 +12,9 @@
 namespace Symfony\Component\Routing;
 
 use Symfony\Component\Config\Loader\LoaderInterface;
-use Symfony\Component\Config\ConfigCache;
+use Symfony\Component\Config\ConfigCacheInterface;
+use Symfony\Component\Config\ConfigCacheFactoryInterface;
+use Symfony\Component\Config\ConfigCacheFactory;
 use Psr\Log\LoggerInterface;
 use Symfony\Component\Routing\Generator\ConfigurableRequirementsInterface;
 use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
@@ -71,6 +73,11 @@ class Router implements RouterInterface, RequestMatcherInterface
      */
     protected $logger;
 
+    /**
+     * @var ConfigCacheFactoryInterface|null
+     */
+    private $configCacheFactory;
+
     /**
      * @var ExpressionFunctionProviderInterface[]
      */
@@ -209,6 +216,16 @@ class Router implements RouterInterface, RequestMatcherInterface
         return $this->context;
     }
 
+    /**
+     * Sets the ConfigCache factory to use.
+     *
+     * @param ConfigCacheFactoryInterface $configCacheFactory The factory to use.
+     */
+    public function setConfigCacheFactory(ConfigCacheFactoryInterface $configCacheFactory)
+    {
+        $this->configCacheFactory = $configCacheFactory;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -262,24 +279,29 @@ class Router implements RouterInterface, RequestMatcherInterface
         }
 
         $class = $this->options['matcher_cache_class'];
-        $cache = new ConfigCache($this->options['cache_dir'].'/'.$class.'.php', $this->options['debug']);
+        $baseClass = $this->options['matcher_base_class'];
-        if (!$cache->isFresh()) {
+        $expressionLanguageProviders = $this->expressionLanguageProviders;
-            $dumper = $this->getMatcherDumperInstance();
+        $that = $this; // required for PHP 5.3 where "$this" cannot be use()d in anonymous functions. Change in Symfony 3.0.
-            if (method_exists($dumper, 'addExpressionLanguageProvider')) {
+
-                foreach ($this->expressionLanguageProviders as $provider) {
+        $cache = $this->getConfigCacheFactory()->cache($this->options['cache_dir'].'/'.$class.'.php',
-                    $dumper->addExpressionLanguageProvider($provider);
+            function (ConfigCacheInterface $cache) use ($that, $class, $baseClass, $expressionLanguageProviders) {
+                $dumper = $that->getMatcherDumperInstance();
+                if (method_exists($dumper, 'addExpressionLanguageProvider')) {
+                    foreach ($expressionLanguageProviders as $provider) {
+                        $dumper->addExpressionLanguageProvider($provider);
+                    }
                 }
+
+                $options = array(
+                    'class' => $class,
+                    'base_class' => $baseClass,
+                );
+
+                $cache->write($dumper->dump($options), $that->getRouteCollection()->getResources());
             }
+        );
 
-            $options = array(
+        require_once $cache->getPath();
-                'class' => $class,
-                'base_class' => $this->options['matcher_base_class'],
-            );
-
-            $cache->write($dumper->dump($options), $this->getRouteCollection()->getResources());
-        }
-
-        require_once $cache;
 
         return $this->matcher = new $class($this->context);
     }
@@ -299,19 +321,22 @@ class Router implements RouterInterface, RequestMatcherInterface
             $this->generator = new $this->options['generator_class']($this->getRouteCollection(), $this->context, $this->logger);
         } else {
             $class = $this->options['generator_cache_class'];
-            $cache = new ConfigCache($this->options['cache_dir'].'/'.$class.'.php', $this->options['debug']);
+            $baseClass = $this->options['generator_base_class'];
-            if (!$cache->isFresh()) {
+            $that = $this; // required for PHP 5.3 where "$this" cannot be use()d in anonymous functions. Change in Symfony 3.0.
-                $dumper = $this->getGeneratorDumperInstance();
+            $cache = $this->getConfigCacheFactory()->cache($this->options['cache_dir'].'/'.$class.'.php',
+                function (ConfigCacheInterface $cache) use ($that, $class, $baseClass) {
+                    $dumper = $that->getGeneratorDumperInstance();
 
-                $options = array(
+                    $options = array(
-                    'class' => $class,
+                        'class' => $class,
-                    'base_class' => $this->options['generator_base_class'],
+                        'base_class' => $baseClass,
-                );
+                    );
 
-                $cache->write($dumper->dump($options), $this->getRouteCollection()->getResources());
+                    $cache->write($dumper->dump($options), $that->getRouteCollection()->getResources());
-            }
+                }
+            );
 
-            require_once $cache;
+            require_once $cache->getPath();
 
             $this->generator = new $class($this->context, $this->logger);
         }
@@ -329,18 +354,37 @@ class Router implements RouterInterface, RequestMatcherInterface
     }
 
     /**
+     * This method is public because it needs to be callable from a closure in PHP 5.3. It should be converted back to protected in 3.0.
+     * @internal
      * @return GeneratorDumperInterface
      */
-    protected function getGeneratorDumperInstance()
+    public function getGeneratorDumperInstance()
     {
         return new $this->options['generator_dumper_class']($this->getRouteCollection());
     }
 
     /**
+     * This method is public because it needs to be callable from a closure in PHP 5.3. It should be converted back to protected in 3.0.
+     * @internal
      * @return MatcherDumperInterface
      */
-    protected function getMatcherDumperInstance()
+    public function getMatcherDumperInstance()
     {
         return new $this->options['matcher_dumper_class']($this->getRouteCollection());
     }
+
+    /**
+     * Provides the ConfigCache factory implementation, falling back to a
+     * default implementation if necessary.
+     *
+     * @return ConfigCacheFactoryInterface $configCacheFactory
+     */
+    private function getConfigCacheFactory()
+    {
+        if (null === $this->configCacheFactory) {
+            $this->configCacheFactory = new ConfigCacheFactory($this->options['debug']);
+        }
+
+        return $this->configCacheFactory;
+    }
 }

src/Symfony/Component/Routing/composer.json

@@ -20,7 +20,7 @@
     },
     "require-dev": {
         "symfony/phpunit-bridge": "~2.7|~3.0.0",
-        "symfony/config": "~2.2|~3.0.0",
+        "symfony/config": "~2.7|~3.0.0",
         "symfony/http-foundation": "~2.3|~3.0.0",
         "symfony/yaml": "~2.0,>=2.0.5|~3.0.0",
         "symfony/expression-language": "~2.4|~3.0.0",
@@ -28,6 +28,9 @@
         "doctrine/common": "~2.2",
         "psr/log": "~1.0"
     },
+    "conflict": {
+        "symfony/config": "<2.7"
+    },
     "suggest": {
         "symfony/config": "For using the all-in-one router or any loader",
         "symfony/yaml": "For using the YAML loader",

src/Symfony/Component/Translation/Translator.php

@@ -13,7 +13,9 @@ namespace Symfony\Component\Translation;
 
 use Symfony\Component\Translation\Loader\LoaderInterface;
 use Symfony\Component\Translation\Exception\NotFoundResourceException;
-use Symfony\Component\Config\ConfigCache;
+use Symfony\Component\Config\ConfigCacheInterface;
+use Symfony\Component\Config\ConfigCacheFactoryInterface;
+use Symfony\Component\Config\ConfigCacheFactory;
 
 /**
  * Translator.
@@ -64,6 +66,11 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
      */
     private $debug;
 
+    /**
+     * @var ConfigCacheFactoryInterface|null
+     */
+    private $configCacheFactory;
+
     /**
      * Constructor.
      *
@@ -84,6 +91,16 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
         $this->debug = $debug;
     }
 
+    /**
+     * Sets the ConfigCache factory to use.
+     *
+     * @param ConfigCacheFactoryInterface $configCacheFactory
+     */
+    public function setConfigCacheFactory(ConfigCacheFactoryInterface $configCacheFactory)
+    {
+        $this->configCacheFactory = $configCacheFactory;
+    }
+
     /**
      * Adds a Loader.
      *
@@ -315,7 +332,7 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
         return $messages;
     }
 
-    /*
+    /**
      * @param string $locale
      */
     protected function loadCatalogue($locale)
@@ -346,21 +363,71 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
 
     /**
      * @param string $locale
-     * @param bool   $forceRefresh
      */
-    private function initializeCacheCatalogue($locale, $forceRefresh = false)
+    private function initializeCacheCatalogue($locale)
     {
         if (isset($this->catalogues[$locale])) {
+            /* Catalogue already initialized. */
             return;
         }
 
         $this->assertValidLocale($locale);
-        $cache = new ConfigCache($this->cacheDir.'/catalogue.'.$locale.'.php', $this->debug);
+        $cacheFile = $this->cacheDir.'/catalogue.'.$locale.'.php';
-        if ($forceRefresh || !$cache->isFresh()) {
+        $self = $this; // required for PHP 5.3 where "$this" cannot be use()d in anonymous functions. Change in Symfony 3.0.
-            $this->initializeCatalogue($locale);
+        $cache = $this->getConfigCacheFactory()->cache($cacheFile,
-            $fallbackContent = $this->getFallbackContent($this->catalogues[$locale]);
+            function (ConfigCacheInterface $cache) use ($self, $locale) {
+                $self->dumpCatalogue($locale, $cache);
+            }
+        );
 
-            $content = sprintf(<<<EOF
+        if (isset($this->catalogues[$locale])) {
+            /* Catalogue has been initialized as it was written out to cache. */
+            return;
+        }
+
+        /* Read catalogue from cache. */
+        $catalogue = include $cache->getPath();
+
+        /*
+         * Gracefully handle the case when the cached catalogue is in an "old" format, without a resourcesHash
+         */
+        $resourcesHash = null;
+        if (is_array($catalogue)) {
+            list($catalogue, $resourcesHash) = $catalogue;
+        }
+
+        if ($this->debug && $resourcesHash !== $this->getResourcesHash($locale)) {
+            /*
+             * This approach of resource checking has the disadvantage that a second
+             * type of freshness check happens based on content *inside* the cache, while
+             * the idea of ConfigCache is to make this check transparent to the client (and keeps
+             * the resources in a .meta file).
+             *
+             * Thus, we might run into the unfortunate situation that we just thought (a few lines above)
+             * that the cache is fresh -- and now that we look into it, we figure it's not.
+             *
+             * For now, just unlink the cache and try again. See
+             * https://github.com/symfony/symfony/pull/11862#issuecomment-54634631 and/or
+             * https://github.com/symfony/symfony/issues/7176 for possible better approaches.
+             */
+            unlink($cacheFile);
+            $this->initializeCacheCatalogue($locale);
+        } else {
+            /* Initialize with catalogue from cache. */
+            $this->catalogues[$locale] = $catalogue;
+        }
+    }
+
+    /**
+     * This method is public because it needs to be callable from a closure in PHP 5.3. It should be made protected (or even private, if possible) in 3.0.
+     * @internal
+     */
+    public function dumpCatalogue($locale, ConfigCacheInterface $cache)
+    {
+        $this->initializeCatalogue($locale);
+        $fallbackContent = $this->getFallbackContent($this->catalogues[$locale]);
+
+        $content = sprintf(<<<EOF
 <?php
 
 use Symfony\Component\Translation\MessageCatalogue;
@@ -372,33 +439,14 @@ use Symfony\Component\Translation\MessageCatalogue;
 return array(\$catalogue, \$resourcesHash);
 
 EOF
-                ,
+            ,
-                $this->getResourcesHash($locale),
+            $this->getResourcesHash($locale),
-                $locale,
+            $locale,
-                var_export($this->catalogues[$locale]->all(), true),
+            var_export($this->catalogues[$locale]->all(), true),
-                $fallbackContent
+            $fallbackContent
-            );
+        );
 
-            $cache->write($content, $this->catalogues[$locale]->getResources());
+        $cache->write($content, $this->catalogues[$locale]->getResources());
-
-            return;
-        }
-
-        $catalogue = include $cache;
-
-        /*
-         * Old cache returns only the catalogue, without resourcesHash
-         */
-        $resourcesHash = null;
-        if (is_array($catalogue)) {
-            list($catalogue, $resourcesHash) = $catalogue;
-        }
-
-        if ($this->debug && $resourcesHash !== $this->getResourcesHash($locale)) {
-            return $this->initializeCacheCatalogue($locale, true);
-        }
-
-        $this->catalogues[$locale] = $catalogue;
     }
 
     private function getFallbackContent(MessageCatalogue $catalogue)
@@ -514,4 +562,19 @@ EOF
             throw new \InvalidArgumentException(sprintf('Invalid "%s" locale.', $locale));
         }
     }
+
+    /**
+     * Provides the ConfigCache factory implementation, falling back to a
+     * default implementation if necessary.
+     *
+     * @return ConfigCacheFactoryInterface $configCacheFactory
+     */
+    private function getConfigCacheFactory()
+    {
+        if (!$this->configCacheFactory) {
+            $this->configCacheFactory = new ConfigCacheFactory($this->debug);
+        }
+
+        return $this->configCacheFactory;
+    }
 }

src/Symfony/Component/Translation/composer.json

@@ -20,11 +20,14 @@
     },
     "require-dev": {
         "symfony/phpunit-bridge": "~2.7|~3.0.0",
-        "symfony/config": "~2.3,>=2.3.12|~3.0.0",
+        "symfony/config": "~2.7",
         "symfony/intl": "~2.3|~3.0.0",
         "symfony/yaml": "~2.2|~3.0.0",
         "psr/log": "~1.0"
     },
+    "conflict": {
+        "symfony/config": "<2.7"
+    },
     "suggest": {
         "symfony/config": "",
         "symfony/yaml": "",