[Messenger] [Redis] Fixed problem where worker stops handling messages on first empty message

rafal-tobola · nicolas-grekas · commit ce103f1d2cb7 · 2023-04-18T11:57:16.000+02:00
diff --git a/src/Symfony/Component/Messenger/Bridge/Redis/Tests/Transport/RedisExtIntegrationTest.php b/src/Symfony/Component/Messenger/Bridge/Redis/Tests/Transport/RedisExtIntegrationTest.php
@@ -14,10 +14,14 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Messenger\Bridge\Redis\Tests\Fixtures\DummyMessage;
 use Symfony\Component\Messenger\Bridge\Redis\Transport\Connection;
+use Symfony\Component\Messenger\Bridge\Redis\Transport\RedisReceiver;
+use Symfony\Component\Messenger\Envelope;
 use Symfony\Component\Messenger\Exception\TransportException;
+use Symfony\Component\Messenger\Transport\Serialization\Serializer;
 
 /**
  * @requires extension redis
+ *
  * @group time-sensitive
  * @group integration
  */
@@ -318,6 +322,30 @@ public function testGetAfterReject()
         $redis->del('messenger-rejectthenget');
     }
 
+    public function testItProperlyHandlesEmptyMessages()
+    {
+        $redisReceiver = new RedisReceiver($this->connection, new Serializer());
+
+        $this->connection->add('{"message": "Hi1"}', ['type' => DummyMessage::class]);
+        $this->connection->add('{"message": "Hi2"}', ['type' => DummyMessage::class]);
+
+        $redisReceiver->get();
+        $this->redis->xtrim('messages', 1);
+
+        // The consumer died during handling a message while performing xtrim in parallel process
+        $this->redis = new \Redis();
+        $this->connection = Connection::fromDsn(getenv('MESSENGER_REDIS_DSN'), ['delete_after_ack' => true], $this->redis);
+        $redisReceiver = new RedisReceiver($this->connection, new Serializer());
+
+        /** @var Envelope[] $envelope */
+        $envelope = $redisReceiver->get();
+        $this->assertCount(1, $envelope);
+
+        $message = $envelope[0]->getMessage();
+        $this->assertInstanceOf(DummyMessage::class, $message);
+        $this->assertEquals('Hi2', $message->getMessage());
+    }
+
     private function getConnectionGroup(Connection $connection): string
     {
         $property = (new \ReflectionClass(Connection::class))->getProperty('group');
diff --git a/src/Symfony/Component/Messenger/Bridge/Redis/Transport/RedisReceiver.php b/src/Symfony/Component/Messenger/Bridge/Redis/Transport/RedisReceiver.php
@@ -14,6 +14,7 @@
 use Symfony\Component\Messenger\Envelope;
 use Symfony\Component\Messenger\Exception\LogicException;
 use Symfony\Component\Messenger\Exception\MessageDecodingFailedException;
+use Symfony\Component\Messenger\Exception\TransportException;
 use Symfony\Component\Messenger\Transport\Receiver\ReceiverInterface;
 use Symfony\Component\Messenger\Transport\Serialization\PhpSerializer;
 use Symfony\Component\Messenger\Transport\Serialization\SerializerInterface;
@@ -44,6 +45,18 @@ public function get(): iterable
             return [];
         }
 
+        if (null === $message['data']) {
+            try {
+                $this->connection->reject($message['id']);
+            } catch (TransportException $e) {
+                if ($e->getPrevious()) {
+                    throw $e;
+                }
+            }
+
+            return $this->get();
+        }
+
         $redisEnvelope = json_decode($message['data']['message'] ?? '', true);
 
         if (null === $redisEnvelope) {
