Associate a static seq variable with a link handle instead of an RPC …

…static variable

src/RPC/RPC.php

@@ -30,11 +30,6 @@ class RPC implements RPCInterface
      */
     private ?string $service = null;
 
-    /**
-     * @var positive-int
-     */
-    private static int $seq = 1;
-
     /**
      * @param RelayInterface $relay
      * @param CodecInterface|null $codec
@@ -76,7 +71,9 @@ public function withCodec(CodecInterface $codec): RPCInterface
      */
     public function call(string $method, $payload, $options = null)
     {
-        $this->relay->send($this->packFrame($method, $payload));
+        $seq = $this->relay->getNextSeq();
+
+        $this->relay->send($this->packFrame($method, $payload, $seq));
 
         // wait for the frame confirmation
         $frame = $this->relay->waitFrame();
@@ -85,12 +82,10 @@ public function call(string $method, $payload, $options = null)
             throw new RPCException('Invalid RPC frame, options missing');
         }
 
-        if ($frame->options[0] !== self::$seq) {
+        if ($frame->options[0] !== $seq) {
             throw new RPCException('Invalid RPC frame, sequence mismatch');
         }
 
-        self::$seq++;
-
         return $this->decodeResponse($frame, $options);
     }
 
@@ -163,13 +158,13 @@ private function decodeResponse(Frame $frame, $options = null)
      * @param mixed $payload
      * @return Frame
      */
-    private function packFrame(string $method, $payload): Frame
+    private function packFrame(string $method, $payload, int $seq): Frame
     {
         if ($this->service !== null) {
             $method = $this->service . '.' . \ucfirst($method);
         }
 
         $body = $method . $this->codec->encode($payload);
-        return new Frame($body, [self::$seq, \strlen($method)], $this->codec->getIndex());
+        return new Frame($body, [$seq, \strlen($method)], $this->codec->getIndex());
     }
 }

src/Relay.php

@@ -13,6 +13,11 @@ abstract class Relay implements RelayInterface
     public const PIPES = 'pipes';
     protected const CONNECTION_EXP = '/(?P<protocol>[^:\/]+):\/\/(?P<arg1>[^:]+)(:(?P<arg2>[^:]+))?/';
 
+    /**
+     * @var int
+     */
+    private int $seq = 1;
+
     /**
      * Create relay using string address.
      *
@@ -93,4 +98,12 @@ private static function openOut(string $output)
 
         return $resource;
     }
+
+    /**
+     * @return int
+     */
+    public function getNextSeq(): int
+    {
+        return $this->seq++;
+    }
 }