[TwigBundle] Fix error page preview for custom twig.exception_controller

src/Symfony/Bundle/TwigBundle/Controller/ExceptionController.php

@@ -19,14 +19,19 @@
 use Symfony\Component\Templating\TemplateReferenceInterface;
 
 /**
- * ExceptionController.
+ * ExceptionController renders error or exception pages for a given
+ * FlattenException.
  *
  * @author Fabien Potencier <fabien@symfony.com>
  * @author Matthias Pigulla <mp@webfactory.de>
  */
 class ExceptionController
 {
     protected $twig;
+
+    /**
+     * @var bool Show error (false) or exception (true) pages by default.
+     */
     protected $debug;
 
     public function __construct(\Twig_Environment $twig, $debug)
@@ -38,6 +43,10 @@ public function __construct(\Twig_Environment $twig, $debug)
     /**
      * Converts an Exception to a Response.
      *
+     * A "showException" request parameter can be used to force display of an error page (when set to false) or
+     * the exception page (when true). If it is not present, the "debug" value passed into the constructor will
+     * be used.
+     *
      * @param Request              $request   The request
      * @param FlattenException     $exception A FlattenException instance
      * @param DebugLoggerInterface $logger    A DebugLoggerInterface instance
@@ -49,25 +58,20 @@ public function __construct(\Twig_Environment $twig, $debug)
     public function showAction(Request $request, FlattenException $exception, DebugLoggerInterface $logger = null)
     {
         $currentContent = $this->getAndCleanOutputBuffering($request->headers->get('X-Php-Ob-Level', -1));
+        $showException = $request->get('showException', $this->debug); // As opposed to an additional parameter, this maintains BC
 
-        return $this->createResponse($request, $exception, $this->debug, $logger, $currentContent);
-    }
-
-    /**
-     * Displays the error page for arbitrary status codes and formats.
-     *
-     * @param Request   $request The request
-     * @param int       $code    The HTTP status code to show the error page for.
-     *
-     * @return Response
-     *
-     * @throws \InvalidArgumentException When the error template does not exist
-     */
-    public function testErrorPageAction(Request $request, $code)
-    {
-        $exception = FlattenException::create(new \Exception("Something has intentionally gone wrong."), $code);
+        $code = $exception->getStatusCode();
 
-        return $this->createResponse($request, $exception, false);
+        return new Response($this->twig->render(
+            $this->findTemplate($request, $request->getRequestFormat(), $code, $showException),
+            array(
+                'status_code' => $code,
+                'status_text' => isset(Response::$statusTexts[$code]) ? Response::$statusTexts[$code] : '',
+                'exception' => $exception,
+                'logger' => $logger,
+                'currentContent' => $currentContent,
+            )
+        ));
     }
 
     /**
@@ -90,19 +94,19 @@ protected function getAndCleanOutputBuffering($startObLevel)
      * @param Request $request
      * @param string  $format
      * @param int     $code       An HTTP response status code
-     * @param bool    $debug
+     * @param bool    $showException
      *
      * @return TemplateReferenceInterface
      */
-    protected function findTemplate(Request $request, $format, $code, $debug)
+    protected function findTemplate(Request $request, $format, $code, $showException)
     {
-        $name = $debug ? 'exception' : 'error';
-        if ($debug && 'html' == $format) {
+        $name = $showException ? 'exception' : 'error';
+        if ($showException && 'html' == $format) {
             $name = 'exception_full';
         }
 
-        // when not in debug, try to find a template for the specific HTTP status code and format
-        if (!$debug) {
+        // For error pages, try to find a template for the specific HTTP status code and format
+        if (!$showException) {
             $template = new TemplateReference('TwigBundle', 'Exception', $name.$code, $format, 'twig');
             if ($this->templateExists($template)) {
                 return $template;
@@ -138,29 +142,4 @@ protected function templateExists($template)
 
         return false;
     }
-
-    /**
-     * @param Request              $request
-     * @param FlattenException     $exception
-     * @param bool                 $debug
-     * @param DebugLoggerInterface $logger
-     * @param string               $currentContent
-     *
-     * @return Response
-     */
-    protected function createResponse(Request $request, FlattenException $exception, $debug, DebugLoggerInterface $logger = null, $currentContent = '')
-    {
-        $code = $exception->getStatusCode();
-
-        return new Response($this->twig->render(
-            (string) $this->findTemplate($request, $request->getRequestFormat(), $code, $debug),
-            array(
-                'status_code' => $code,
-                'status_text' => isset(Response::$statusTexts[$code]) ? Response::$statusTexts[$code] : '',
-                'exception' => $exception,
-                'logger' => $logger,
-                'currentContent' => $currentContent,
-            )
-        ));
-    }
 }

src/Symfony/Bundle/TwigBundle/Controller/PreviewErrorController.php

@@ -0,0 +1,56 @@
+<?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\Bundle\TwigBundle\Controller;
+
+use Symfony\Component\HttpKernel\Exception\FlattenException;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * PreviewErrorController can be used to test error pages.
+ *
+ * It will create a test exception and forward it to another controller.
+ *
+ * @author Matthias Pigulla <mp@webfactory.de>
+ */
+class PreviewErrorController
+{
+    protected $kernel;
+    protected $controller;
+
+    public function __construct(HttpKernelInterface $kernel, $controller)
+    {
+        $this->kernel = $kernel;
+        $this->controller = $controller;
+    }
+
+    public function previewErrorPageAction(Request $request, $code)
+    {
+        $exception = FlattenException::create(new \Exception("Something has intentionally gone wrong."), $code);
+
+        /*
+         * This Request mimics the parameters set by
+         * \Symfony\Component\HttpKernel\EventListener\ExceptionListener::duplicateRequest, with
+         * the additional "showException" flag.
+         */
+
+        $subRequest = $request->duplicate(null, null, array(
+            '_controller' => $this->controller,
+            'exception' => $exception,
+            'logger' => null,
+            'format' => $request->getRequestFormat(),
+            'showException' => false,
+        ));
+
+        return $this->kernel->handle($subRequest, HttpKernelInterface::SUB_REQUEST);
+    }
+}

src/Symfony/Bundle/TwigBundle/Resources/config/routing/errors.xml

@@ -5,7 +5,7 @@
     xsi:schemaLocation="http://symfony.com/schema/routing http://symfony.com/schema/routing/routing-1.0.xsd">
 
     <route id="_twig_error_test" path="/{code}.{_format}">
-        <default key="_controller">twig.controller.exception:testErrorPageAction</default>
+        <default key="_controller">twig.controller.preview_error:previewErrorPageAction</default>
         <default key="_format">html</default>
         <requirement key="code">\d+</requirement>
     </route>

src/Symfony/Bundle/TwigBundle/Resources/config/twig.xml

@@ -25,6 +25,7 @@
         <parameter key="twig.translation.extractor.class">Symfony\Bridge\Twig\Translation\TwigExtractor</parameter>
         <parameter key="twig.exception_listener.class">Symfony\Component\HttpKernel\EventListener\ExceptionListener</parameter>
         <parameter key="twig.controller.exception.class">Symfony\Bundle\TwigBundle\Controller\ExceptionController</parameter>
+        <parameter key="twig.controller.preview_error.class">Symfony\Bundle\TwigBundle\Controller\PreviewErrorController</parameter>
     </parameters>
 
     <services>
@@ -133,5 +134,10 @@
             <argument type="service" id="twig" />
             <argument>%kernel.debug%</argument>
         </service>
+
+        <service id="twig.controller.preview_error" class="%twig.controller.preview_error.class%">
+            <argument type="service" id="http_kernel" />
+            <argument>%twig.exception_listener.controller%</argument>
+        </service>
     </services>
 </container>

src/Symfony/Bundle/TwigBundle/Tests/Controller/ExceptionControllerTest.php

@@ -13,6 +13,7 @@
 
 use Symfony\Bundle\TwigBundle\Tests\TestCase;
 use Symfony\Bundle\TwigBundle\Controller\ExceptionController;
+use Symfony\Component\HttpKernel\Exception\FlattenException;
 use Symfony\Component\HttpFoundation\Request;
 
 class ExceptionControllerTest extends TestCase
@@ -42,27 +43,22 @@ public function testOnlyClearOwnOutputBuffers()
         $controller->showAction($request, $flatten);
     }
 
-    public function testErrorPagesInDebugMode()
+    public function testShowActionCanBeForcedToShowErrorPage()
     {
         $twig = new \Twig_Environment(
             new \Twig_Loader_Array(array(
-                'TwigBundle:Exception:error404.html.twig' => '
-                    {%- if exception is defined and status_text is defined and status_code is defined -%}
-                        OK
-                    {%- else -%}
-                        "exception" variable is missing
-                    {%- endif -%}
-                ',
+                'TwigBundle:Exception:error404.html.twig' => 'ok',
             ))
         );
 
-        $request = Request::create('whatever');
+        $request = Request::create('whatever', 'GET', array('showException' => false));
+        $exception = FlattenException::create(new \Exception(), 404);
+        $controller = new ExceptionController($twig, /* "showException" defaults to --> */ true);
 
-        $controller = new ExceptionController($twig, /* "debug" set to --> */ true);
-        $response = $controller->testErrorPageAction($request, 404);
+        $response = $controller->showAction($request, $exception, null);
 
         $this->assertEquals(200, $response->getStatusCode()); // successful request
-        $this->assertEquals('OK', $response->getContent());  // content of the error404.html template
+        $this->assertEquals('ok', $response->getContent());  // content of the error404.html template
     }
 
     public function testFallbackToHtmlIfNoTemplateForRequestedFormat()
@@ -75,9 +71,10 @@ public function testFallbackToHtmlIfNoTemplateForRequestedFormat()
 
         $request = Request::create('whatever');
         $request->setRequestFormat('txt');
-
+        $exception = FlattenException::create(new \Exception());
         $controller = new ExceptionController($twig, false);
-        $response = $controller->testErrorPageAction($request, 42);
+
+        $response = $controller->showAction($request, $exception);
 
         $this->assertEquals('html', $request->getRequestFormat());
     }

src/Symfony/Bundle/TwigBundle/Tests/Controller/PreviewErrorControllerTest.php

@@ -0,0 +1,56 @@
+<?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\Bundle\TwigBundle\Tests\Controller;
+
+use Symfony\Bundle\TwigBundle\Controller\PreviewErrorController;
+use Symfony\Bundle\TwigBundle\Tests\TestCase;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
+
+class PreviewErrorControllerTest extends TestCase
+{
+    public function testForwardRequestToConfiguredController()
+    {
+        $self = $this;
+
+        $request = Request::create('whatever');
+        $response = new Response("");
+        $code = 123;
+        $logicalControllerName = 'foo:bar:baz';
+
+        $kernel = $this->getMock('\Symfony\Component\HttpKernel\HttpKernelInterface');
+        $kernel
+            ->expects($this->once())
+            ->method('handle')
+            ->with(
+                $this->callback(function (Request $request) use ($self, $logicalControllerName, $code) {
+
+                    $self->assertEquals($logicalControllerName, $request->attributes->get('_controller'));
+
+                    $exception = $request->attributes->get('exception');
+                    $self->assertInstanceOf('Symfony\Component\HttpKernel\Exception\FlattenException', $exception);
+                    $self->assertEquals($code, $exception->getStatusCode());
+
+                    $self->assertFalse($request->attributes->get('showException'));
+
+                    return true;
+                }),
+                $this->equalTo(HttpKernelInterface::SUB_REQUEST)
+            )
+            ->will($this->returnValue($response));
+
+        $controller = new PreviewErrorController($kernel, $logicalControllerName);
+
+        $this->assertSame($response, $controller->previewErrorPageAction($request, $code));
+    }
+}