refactor(Messenger): refactoring on get() usage

Author: Guikingone

components/messenger.rst

@@ -284,17 +284,16 @@ do is to write your own CSV receiver::
 
         public function get(): void
         {
-            $ordersFromCsv = $this->serializer->deserialize(file_get_contents($this->filePath), 'csv');
-
-            foreach ($ordersFromCsv as $orderFromCsv) {
-                $order = new NewOrder($orderFromCsv['id'], $orderFromCsv['account_id'], $orderFromCsv['amount']);
-
-                $envelope = new Envelope($order);
-
-                $handler($envelope);
+            // Receive the envelope according to your transport ($yourEnvelope here),
+            // in most case, using a connection is the easiest solution.
+            
+            if (null === $yourEnvelope) {
+                return [];
             }
-
-            return [$envelope];
+            
+            // Reject the message if needed
+            
+            return [$yourEnvelope->with(new CustomStamp($yourEnvelope['id']);
         }
 
         public function ack(Envelope $envelope): void