symfony · ogizanagi · Nov 8, 2019
diff --git a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
@@ -4,6 +4,7 @@ CHANGELOG
 5.1.0
 -----
 
+ * Wired the `send_mail_after_current_bus` middleware by default in message buses, so mails are sent only after the main message succeeded
  * Added the `framework.router.context` configuration node to configure the `RequestContext`
  * Made `MicroKernelTrait::configureContainer()` compatible with `ContainerConfigurator`
  * Added a new `mailer.message_bus` option to configure or disable the message bus to use to send mails.

diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
@@ -81,6 +81,7 @@
 use Symfony\Component\Mailer\Bridge\Postmark\Transport\PostmarkTransportFactory;
 use Symfony\Component\Mailer\Bridge\Sendgrid\Transport\SendgridTransportFactory;
 use Symfony\Component\Mailer\Mailer;
+use Symfony\Component\Mailer\Messenger\Middleware\SendMailAfterCurrentBusMiddleware;
 use Symfony\Component\Messenger\Handler\MessageHandlerInterface;
 use Symfony\Component\Messenger\MessageBus;
 use Symfony\Component\Messenger\MessageBusInterface;
@@ -1581,6 +1582,7 @@ private function registerMessengerConfiguration(array $config, ContainerBuilder
             'before' => [
                 ['id' => 'add_bus_name_stamp_middleware'],
                 ['id' => 'reject_redelivered_message_middleware'],
+                ['id' => 'send_mail_after_current_bus'],
                 ['id' => 'dispatch_after_current_bus'],
                 ['id' => 'failed_message_processing_middleware'],
             ],
@@ -1589,6 +1591,13 @@ private function registerMessengerConfiguration(array $config, ContainerBuilder
                 ['id' => 'handle_message'],
             ],
         ];
+
+        if (!class_exists(SendMailAfterCurrentBusMiddleware::class)) {
+            $container->removeDefinition('messenger.middleware.send_mail_after_current_bus');
+            $beforeMiddleware = &$defaultMiddleware['before'];
+            array_splice($beforeMiddleware, 2, 1);
+        }
+
         foreach ($config['buses'] as $busId => $bus) {
             $middleware = $bus['middleware'];
 

diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/messenger.xml b/src/Symfony/Bundle/FrameworkBundle/Resources/config/messenger.xml
@@ -44,6 +44,8 @@
 
         <service id="messenger.middleware.dispatch_after_current_bus" class="Symfony\Component\Messenger\Middleware\DispatchAfterCurrentBusMiddleware" />
 
+        <service id="messenger.middleware.send_mail_after_current_bus" class="Symfony\Component\Mailer\Messenger\Middleware\SendMailAfterCurrentBusMiddleware" />
+
         <service id="messenger.middleware.validation" class="Symfony\Component\Messenger\Middleware\ValidationMiddleware">
             <argument type="service" id="validator" />
         </service>

diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php
@@ -39,6 +39,7 @@
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpClient\ScopingHttpClient;
 use Symfony\Component\HttpKernel\DependencyInjection\LoggerPass;
+use Symfony\Component\Mailer\Messenger\Middleware\SendMailAfterCurrentBusMiddleware;
 use Symfony\Component\Messenger\Transport\TransportFactory;
 use Symfony\Component\PropertyAccess\PropertyAccessor;
 use Symfony\Component\Serializer\Mapping\Loader\AnnotationLoader;
@@ -638,25 +639,41 @@ public function testMessengerWithMultipleBuses()
 
         $this->assertTrue($container->has('messenger.bus.commands'));
         $this->assertSame([], $container->getDefinition('messenger.bus.commands')->getArgument(0));
-        $this->assertEquals([
+
+        $expectedMiddleware = [
             ['id' => 'add_bus_name_stamp_middleware', 'arguments' => ['messenger.bus.commands']],
             ['id' => 'reject_redelivered_message_middleware'],
+            ['id' => 'send_mail_after_current_bus'],
             ['id' => 'dispatch_after_current_bus'],
             ['id' => 'failed_message_processing_middleware'],
             ['id' => 'send_message'],
             ['id' => 'handle_message'],
-        ], $container->getParameter('messenger.bus.commands.middleware'));
+        ];
+
+        if (!class_exists(SendMailAfterCurrentBusMiddleware::class)) {
+            array_splice($expectedMiddleware, 2, 1);
+        }
+        $this->assertEquals($expectedMiddleware, $container->getParameter('messenger.bus.commands.middleware'));
+
         $this->assertTrue($container->has('messenger.bus.events'));
         $this->assertSame([], $container->getDefinition('messenger.bus.events')->getArgument(0));
-        $this->assertEquals([
+
+        $expectedMiddleware = [
             ['id' => 'add_bus_name_stamp_middleware', 'arguments' => ['messenger.bus.events']],
             ['id' => 'reject_redelivered_message_middleware'],
+            ['id' => 'send_mail_after_current_bus'],
             ['id' => 'dispatch_after_current_bus'],
             ['id' => 'failed_message_processing_middleware'],
             ['id' => 'with_factory', 'arguments' => ['foo', true, ['bar' => 'baz']]],
             ['id' => 'send_message'],
             ['id' => 'handle_message'],
-        ], $container->getParameter('messenger.bus.events.middleware'));
+        ];
+
+        if (!class_exists(SendMailAfterCurrentBusMiddleware::class)) {
+            array_splice($expectedMiddleware, 2, 1);
+        }
+        $this->assertEquals($expectedMiddleware, $container->getParameter('messenger.bus.events.middleware'));
+
         $this->assertTrue($container->has('messenger.bus.queries'));
         $this->assertSame([], $container->getDefinition('messenger.bus.queries')->getArgument(0));
         $this->assertEquals([

diff --git a/src/Symfony/Component/Mailer/CHANGELOG.md b/src/Symfony/Component/Mailer/CHANGELOG.md
@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+5.1.0
+-----
+
+ * Added `SendMailAfterCurrentBusMiddleware` to send mails from message buses only after the main message succeeded
+
 4.4.0
 -----
 

diff --git a/src/Symfony/Component/Mailer/Messenger/Middleware/SendMailAfterCurrentBusMiddleware.php b/src/Symfony/Component/Mailer/Messenger/Middleware/SendMailAfterCurrentBusMiddleware.php
@@ -0,0 +1,52 @@
+<?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\Mailer\Messenger\Middleware;
+
+use Symfony\Component\Mailer\Messenger\SendEmailMessage;
+use Symfony\Component\Messenger\Envelope;
+use Symfony\Component\Messenger\Middleware\MiddlewareInterface;
+use Symfony\Component\Messenger\Middleware\StackInterface;
+use Symfony\Component\Messenger\Stamp\DispatchAfterCurrentBusStamp;
+
+/**
+ * Automatically adds a stamp to mail messages, so these are only dispatched once the main message handler(s) succeeded.
+ * It prevents sending mails despite the main process failed.
+ * MUST be registered before the dispatch_after_current_bus middleware so the stamp is taken into account.
+ *
+ * @see \Symfony\Component\Messenger\Middleware\DispatchAfterCurrentBusMiddleware
+ *
+ * @author Maxime Steinhausser <maxime.steinhausser@gmail.com>
+ */
+class SendMailAfterCurrentBusMiddleware implements MiddlewareInterface
+{
+    /**
+     * @var bool this property is used to signal if we are inside a the first/root call to
+     *           MessageBusInterface::dispatch() or if dispatch has been called inside a message handler
+     */
+    private $isRootDispatchCallRunning = false;
+
+    public function handle(Envelope $envelope, StackInterface $stack): Envelope
+    {
+        try {
+            if ($this->isRootDispatchCallRunning && $envelope->getMessage() instanceof SendEmailMessage) {
+                $envelope = $envelope->with(new DispatchAfterCurrentBusStamp());
+            }
+
+            // First time we get here, mark as inside a "root dispatch" call:
+            $this->isRootDispatchCallRunning = true;
+
+            return $stack->next()->handle($envelope, $stack);
+        } finally {
+            $this->isRootDispatchCallRunning = false;
+        }
+    }
+}
diff --git a/...ony/Component/Mailer/Tests/Messenger/Middleware/SendMailAfterCurrentBusMiddlewareTest.php b/...ony/Component/Mailer/Tests/Messenger/Middleware/SendMailAfterCurrentBusMiddlewareTest.php
@@ -0,0 +1,87 @@
+<?php
+
+namespace Symfony\Component\Mailer\Tests\Messenger\Middleware;
+
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Mailer\Messenger\Middleware\SendMailAfterCurrentBusMiddleware;
+use Symfony\Component\Mailer\Messenger\SendEmailMessage;
+use Symfony\Component\Messenger\Envelope;
+use Symfony\Component\Messenger\MessageBus;
+use Symfony\Component\Messenger\MessageBusInterface;
+use Symfony\Component\Messenger\Middleware\DispatchAfterCurrentBusMiddleware;
+use Symfony\Component\Messenger\Middleware\MiddlewareInterface;
+use Symfony\Component\Messenger\Middleware\StackInterface;
+use Symfony\Component\Mime\RawMessage;
+
+class SendMailAfterCurrentBusMiddlewareTest extends TestCase
+{
+    public function testMailSentAfterMainMessage()
+    {
+        $message = new DummyMessage();
+        $sendMail = new SendEmailMessage(new RawMessage('foo'));
+
+        $middleware = new SendMailAfterCurrentBusMiddleware();
+        $handlingMiddleware = $this->createMock(MiddlewareInterface::class);
+
+        $bus = new MessageBus([
+            $middleware,
+            new DispatchAfterCurrentBusMiddleware(),
+            $dispatchingMiddleware = new DispatchingMiddleware([
+                $sendMail,
+            ]),
+            $handlingMiddleware,
+        ]);
+
+        $dispatchingMiddleware->setBus($bus);
+
+        // Expect main dispatched message to be handled first:
+        $this->expectHandledMessage($handlingMiddleware, 0, $message);
+        // Then, expect mail to be sent:
+        $this->expectHandledMessage($handlingMiddleware, 1, $sendMail);
+
+        $bus->dispatch($message);
+    }
+
+    /**
+     * @param MiddlewareInterface|MockObject $handlingMiddleware
+     */
+    private function expectHandledMessage(MiddlewareInterface $handlingMiddleware, int $at, $message): void
+    {
+        $handlingMiddleware->expects($this->at($at))->method('handle')->with($this->callback(function (Envelope $envelope) use ($message) {
+            return $envelope->getMessage() === $message;
+        }))->willReturnCallback(function ($envelope, StackInterface $stack) {
+            return $stack->next()->handle($envelope, $stack);
+        });
+    }
+}
+
+class DummyMessage
+{
+}
+
+class DispatchingMiddleware implements MiddlewareInterface
+{
+    /** @var MessageBusInterface */
+    private $bus;
+    private $messages;
+
+    public function __construct(array $messages)
+    {
+        $this->messages = $messages;
+    }
+
+    public function setBus(MessageBusInterface $bus): void
+    {
+        $this->bus = $bus;
+    }
+
+    public function handle(Envelope $envelope, StackInterface $stack): Envelope
+    {
+        while ($message = array_shift($this->messages)) {
+            $this->bus->dispatch($message);
+        }
+
+        return $stack->next()->handle($envelope, $stack);
+    }
+}