A solution to resolve #983 (bad comportment of Translator)

src/Silex/Provider/Translation/Translator.php

-<?php
-
-/*
- * This file is part of the Silex framework.
- *
- * (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 Silex\Provider\Translation;
-
-use Pimple\Container;
-use Symfony\Component\Translation\Translator as BaseTranslator;
-use Symfony\Component\Translation\MessageSelector;
-
-/**
- * Translator that gets the current locale from the container.
- *
- * @author Fabien Potencier <fabien@symfony.com>
- */
-class Translator extends BaseTranslator
-{
-    protected $app;
-
-    public function __construct(Container $app, MessageSelector $selector)
-    {
-        $this->app = $app;
-
-        parent::__construct(null, $selector);
-    }
-
-    public function getLocale()
-    {
-        return $this->app['locale'];
-    }
-
-    public function setLocale($locale)
-    {
-        $this->app['locale'] = $locale;
-
-        parent::setLocale($locale);
-    }
-}

src/Silex/Provider/Translation/TranslatorListener.php

+<?php
+
+/*
+ * This file is part of the Silex framework.
+ *
+ * (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 Silex\Provider\Translation;
+
+use Symfony\Component\HttpKernel\KernelEvents;
+use Symfony\Component\HttpKernel\Event\GetResponseEvent;
+use Symfony\Component\HttpKernel\Event\FinishRequestEvent;
+use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+use Symfony\Component\Translation\TranslatorInterface;
+
+/**
+ * Initializes the Translator locale based on the Request locale.
+ *
+ * This listener works in 2 modes:
+ *
+ *  * 2.3 compatibility mode where you must call setRequest whenever the Request changes.
+ *  * 2.4+ mode where you must pass a RequestStack instance in the constructor.
+ *
+ * @author Mathieu Poisbeau <freepius44@gmail.com>
+ */
+class TranslatorListener implements EventSubscriberInterface
+{
+    protected $translator;
+    protected $requestStack;
+
+    /**
+     * RequestStack will become required in 3.0.
+     */
+    public function __construct(TranslatorInterface $translator, RequestStack $requestStack = null)
+    {
+        $this->translator = $translator;
+        $this->requestStack = $requestStack;
+    }
+
+    /**
+     * Sets the current Request.
+     *
+     * This method was used to synchronize the Request, but as the HttpKernel
+     * is doing that automatically now, you should never call it directly.
+     * It is kept public for BC with the 2.3 version.
+     *
+     * @param Request|null $request A Request instance
+     *
+     * @deprecated Deprecated since version 2.4, to be removed in 3.0.
+     */
+    public function setRequest(Request $request = null)
+    {
+        if (null === $request) {
+            return;
+        }
+
+        $this->translator->setLocale($request->getLocale());
+    }
+
+    public function onKernelRequest(GetResponseEvent $event)
+    {
+        $this->translator->setLocale($event->getRequest()->getLocale());
+    }
+
+    public function onKernelFinishRequest(FinishRequestEvent $event)
+    {
+        if (null === $this->requestStack) {
+            return; // removed when requestStack is required
+        }
+
+        if (null !== $parentRequest = $this->requestStack->getParentRequest()) {
+            $this->translator->setLocale($parentRequest->getLocale());
+        }
+    }
+
+    public static function getSubscribedEvents()
+    {
+        return array(
+            KernelEvents::REQUEST => array(array('onKernelRequest', 0)),
+            KernelEvents::FINISH_REQUEST => array(array('onKernelFinishRequest', 0)),
+        );
+    }
+}

src/Silex/Provider/TranslationServiceProvider.php

@@ -13,26 +13,29 @@ namespace Silex\Provider;
 
 use Pimple\Container;
 use Pimple\ServiceProviderInterface;
-use Silex\Provider\Translation\Translator;
+use Symfony\Component\Translation\Translator;
 use Symfony\Component\Translation\MessageSelector;
 use Symfony\Component\Translation\Loader\ArrayLoader;
 use Symfony\Component\Translation\Loader\XliffFileLoader;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Silex\Api\EventListenerProviderInterface;
+use Silex\Provider\Translation\TranslatorListener;
 
 /**
  * Symfony Translation component Provider.
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class TranslationServiceProvider implements ServiceProviderInterface
+class TranslationServiceProvider implements ServiceProviderInterface, EventListenerProviderInterface
 {
     public function register(Container $app)
     {
         $app['translator'] = function ($app) {
             if (!isset($app['locale'])) {
-                throw new \LogicException('You must register the LocaleServiceProvider to use the TranslationServiceProvider');
+                throw new \LogicException('You must define \'locale\' parameter or register the LocaleServiceProvider to use the TranslationServiceProvider');
             }
 
-            $translator = new Translator($app, $app['translator.message_selector']);
+            $translator = new Translator($app['locale'], $app['translator.message_selector']);
             $translator->setFallbackLocales($app['locale_fallbacks']);
             $translator->addLoader('array', new ArrayLoader());
             $translator->addLoader('xliff', new XliffFileLoader());
@@ -46,6 +49,10 @@ class TranslationServiceProvider implements ServiceProviderInterface
             return $translator;
         };
 
+        $app['translator.listener'] = function ($app) {
+            return new TranslatorListener($app['translator'], $app['request_stack']);
+        };
+
         $app['translator.message_selector'] = function () {
             return new MessageSelector();
         };
@@ -53,4 +60,10 @@ class TranslationServiceProvider implements ServiceProviderInterface
         $app['translator.domains'] = array();
         $app['locale_fallbacks'] = array('en');
     }
+
+
+    public function subscribe(Container $app, EventDispatcherInterface $dispatcher)
+    {
+        $dispatcher->addSubscriber($app['translator.listener']);
+    }
 }

tests/Silex/Tests/Provider/TranslationServiceProviderTest.php

@@ -14,6 +14,8 @@ namespace Silex\Tests\Provider;
 use Silex\Application;
 use Silex\Provider\TranslationServiceProvider;
 use Silex\Provider\LocaleServiceProvider;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
 
 /**
  * TranslationProvider test cases.
@@ -118,26 +120,62 @@ class TranslationServiceProviderTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals('The german translation', $result);
     }
 
-    public function testChangingLocale()
+    public function testLocale()
     {
         $app = $this->getPreparedApp();
+        $app->get('/', function () use ($app) { return $app['translator']->getLocale(); });
+        $response = $app->handle(Request::create('/'));
+        $this->assertEquals('en', $response->getContent());
 
-        $this->assertEquals('The translation', $app['translator']->trans('key1'));
-
-        $app['locale'] = 'de';
+        $app = $this->getPreparedApp();
+        $app->get('/', function () use ($app) { return $app['translator']->getLocale(); });
+        $request = Request::create('/');
+        $request->setLocale('fr');
+        $response = $app->handle($request);
+        $this->assertEquals('fr', $response->getContent());
 
-        $this->assertEquals('The german translation', $app['translator']->trans('key1'));
+        $app = $this->getPreparedApp();
+        $app->get('/{_locale}', function () use ($app) { return $app['translator']->getLocale(); });
+        $response = $app->handle(Request::create('/es'));
+        $this->assertEquals('es', $response->getContent());
     }
 
-    public function testChangingLocaleViaTranslator()
+    public function testLocaleInSubRequests()
     {
         $app = $this->getPreparedApp();
+        $app->get('/embed/{_locale}', function () use ($app) { return $app['translator']->getLocale(); });
+        $app->get('/{_locale}', function () use ($app) {
+            return $app['translator']->getLocale().
+                   $app->handle(Request::create('/embed/es'), HttpKernelInterface::SUB_REQUEST)->getContent().
+                   $app['translator']->getLocale();
+        });
+        $response = $app->handle(Request::create('/fr'));
+        $this->assertEquals('fresfr', $response->getContent());
 
-        $this->assertEquals('The translation', $app['translator']->trans('key1'));
-
-        $app['translator']->setLocale('de');
+        $app = $this->getPreparedApp();
+        $app->get('/embed', function () use ($app) { return $app['translator']->getLocale(); });
+        $app->get('/{_locale}', function () use ($app) {
+            return $app['translator']->getLocale().
+                   $app->handle(Request::create('/embed'), HttpKernelInterface::SUB_REQUEST)->getContent().
+                   $app['translator']->getLocale();
+        });
+        $response = $app->handle(Request::create('/fr'));
+        // locale in sub-request must be "en" as this is the value if the sub-request is converted to an ESI
+        $this->assertEquals('frenfr', $response->getContent());
+    }
 
-        $this->assertEquals('The german translation', $app['translator']->trans('key1'));
-        $this->assertEquals('de', $app['locale']);
+    public function testLocaleWithBefore()
+    {
+        $app = $this->getPreparedApp();
+        $app->before(function (Request $request) { $request->setLocale('fr'); });
+        $app->get('/embed', function () use ($app) { return $app['translator']->getLocale(); });
+        $app->get('/', function () use ($app) {
+            return $app['translator']->getLocale().
+                $app->handle(Request::create('/embed'), HttpKernelInterface::SUB_REQUEST)->getContent().
+                $app['translator']->getLocale();
+        });
+        $response = $app->handle(Request::create('/'));
+        // locale in sub-request is "en" as the before filter is only executed for the main request
+        $this->assertEquals('frenfr', $response->getContent());
     }
 }