Add JsonRpcNotification and abstract Notification

Author: paulbalandan

src/Message/JsonRpcNotification.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of the Nexus MCP SDK package.
+ *
+ * (c) 2025 John Paul E. Balandan, CPA <[email protected]>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Nexus\Mcp\Message;
+
+/**
+ * A notification which does not expect a response.
+ */
+final readonly class JsonRpcNotification extends Notification
+{
+    public function __construct(string $jsonrpc, string $method, ?array $params = null)
+    {
+        parent::__construct($jsonrpc, $method, $params);
+    }
+
+    /**
+     * @return array{
+     *   jsonrpc: non-empty-string,
+     *   method: non-empty-string,
+     *   params?: null|array<string, mixed>,
+     * }
+     */
+    #[\Override]
+    public function toArray(): array
+    {
+        return array_filter([
+            'jsonrpc' => $this->jsonrpc,
+            'method' => $this->method,
+            'params' => $this->params,
+        ], static fn(mixed $value): bool => null !== $value);
+    }
+}

src/Message/Notification.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of the Nexus MCP SDK package.
+ *
+ * (c) 2025 John Paul E. Balandan, CPA <[email protected]>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Nexus\Mcp\Message;
+
+/**
+ * The base JSON-RPC notification object.
+ */
+abstract readonly class Notification extends Message
+{
+    /**
+     * @param non-empty-string          $jsonrpc
+     * @param non-empty-string          $method
+     * @param null|array<string, mixed> $params
+     */
+    public function __construct(
+        string $jsonrpc,
+        public string $method,
+        public ?array $params = null,
+    ) {
+        parent::__construct($jsonrpc);
+    }
+}

tests/Message/JsonRpcNotificationTest.php

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of the Nexus MCP SDK package.
+ *
+ * (c) 2025 John Paul E. Balandan, CPA <[email protected]>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Nexus\Mcp\Tests\Message;
+
+use Nexus\Mcp\Message\JsonRpcNotification;
+use Nexus\Mcp\Message\Notification;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ */
+#[CoversClass(JsonRpcNotification::class)]
+#[CoversClass(Notification::class)]
+final class JsonRpcNotificationTest extends TestCase
+{
+    public function testNotificationCanBeJsonSerialized(): void
+    {
+        $notification = new JsonRpcNotification('2.0', 'initialized');
+        self::assertSame([
+            'jsonrpc' => '2.0',
+            'method' => 'initialized',
+        ], $notification->toArray());
+        self::assertSame('{"jsonrpc":"2.0","method":"initialized"}', json_encode($notification));
+    }
+
+    public function testNotificationWithParamsCanBeJsonSerialized(): void
+    {
+        $notification = new JsonRpcNotification(
+            '2.0',
+            'initialized',
+            ['param1' => 'value1', 'param2' => 'value2'],
+        );
+        self::assertSame([
+            'jsonrpc' => '2.0',
+            'method' => 'initialized',
+            'params' => ['param1' => 'value1', 'param2' => 'value2'],
+        ], $notification->toArray());
+        self::assertSame(
+            '{"jsonrpc":"2.0","method":"initialized","params":{"param1":"value1","param2":"value2"}}',
+            json_encode($notification),
+        );
+    }
+}