Add envelope stack

src/Message/EnvelopeInterface.php

@@ -9,6 +9,8 @@
  */
 interface EnvelopeInterface extends MessageInterface
 {
+    public const ENVELOPE_STACK_KEY = 'envelopes';
+
     public function getMessage(): MessageInterface;
 
     public function withMessage(MessageInterface $message): self;

src/Message/EnvelopeTrait.php

@@ -33,6 +33,17 @@ public function getData(): mixed
 
     public function getMetadata(): array
     {
-        return $this->message->getMetadata();
+        return array_merge($this->message->getMetadata(), [
+            self::ENVELOPE_STACK_KEY => array_merge(
+                $this->message->getMetadata()[self::ENVELOPE_STACK_KEY] ?? [],
+                [self::class],
+            ),
+            ...$this->getEnvelopeMetadata(),
+        ]);
+    }
+
+    public function getEnvelopeMetadata(): array
+    {
+        return [];
     }
 }

src/Message/IdEnvelope.php

@@ -29,10 +29,8 @@ public function getId(): string|int|null
         return $this->id ?? $this->message->getMetadata()[self::MESSAGE_ID_KEY] ?? null;
     }
 
-    public function getMetadata(): array
+    public function getEnvelopeMetadata(): array
     {
-        return array_merge($this->message->getMetadata(), [
-            self::MESSAGE_ID_KEY => $this->getId(),
-        ]);
+        return [self::MESSAGE_ID_KEY => $this->getId()];
     }
 }

tests/Unit/EnvelopeTest.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Unit;
+
+use PHPUnit\Framework\TestCase;
+use Yiisoft\Queue\Message\EnvelopeInterface;
+use Yiisoft\Queue\Message\IdEnvelope;
+use Yiisoft\Queue\Message\Message;
+
+final class EnvelopeTest extends TestCase
+{
+    public function testEnvelopeStack(): void
+    {
+        $message = new Message('handler', 'test');
+        $message = new IdEnvelope($message, 'test-id');
+
+        $this->assertEquals('test', $message->getMessage()->getData());
+
+        $stack = $message->getMetadata()[EnvelopeInterface::ENVELOPE_STACK_KEY];
+        $this->assertIsArray($stack);
+
+        $this->assertEquals([
+            IdEnvelope::class,
+        ], $stack);
+    }
+
+    public function testEnvelopeDuplicates(): void
+    {
+        $message = new Message('handler', 'test');
+        $message = new IdEnvelope($message, 'test-id');
+        $message = new IdEnvelope($message, 'test-id');
+        $message = new IdEnvelope($message, 'test-id');
+
+        $this->assertEquals('test', $message->getMessage()->getData());
+
+        $stack = $message->getMetadata()[EnvelopeInterface::ENVELOPE_STACK_KEY];
+        $this->assertIsArray($stack);
+
+        $this->assertEquals([
+            IdEnvelope::class,
+            IdEnvelope::class,
+            IdEnvelope::class,
+        ], $stack);
+    }
+}