Add Message interfaces for messages

Author: WyriHaximus

src/Message.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ReactParallel\ObjectProxy;
+
+interface Message
+{
+    public function hash(): string;
+
+    public function objectHash(): string;
+}

src/Message/Call.php

@@ -5,8 +5,9 @@
 namespace ReactParallel\ObjectProxy\Message;
 
 use parallel\Channel;
+use ReactParallel\ObjectProxy\Message;
 
-final class Call
+final class Call implements Message
 {
     private Channel $channel;
 

src/Message/Destruct.php

@@ -4,7 +4,9 @@
 
 namespace ReactParallel\ObjectProxy\Message;
 
-final class Destruct
+use ReactParallel\ObjectProxy\Message;
+
+final class Destruct implements Message
 {
     private string $hash;
     private string $objectHash;

src/Proxy.php

@@ -102,7 +102,7 @@ public function __destruct()
 
     private function setUpHandlers(): void
     {
-        $this->factory->streams()->channel($this->in)->subscribe(function (object $message): void {
+        $this->factory->streams()->channel($this->in)->subscribe(function (Message $message): void {
             if ($message instanceof Call) {
                 $this->handleCall($message);
             }