feat: Allow any normalizable result from a tool

src/Chain/Toolbox/ToolResultConverter.php

@@ -4,32 +4,33 @@
 
 namespace PhpLlm\LlmChain\Chain\Toolbox;
 
+use Symfony\Component\Serializer\Encoder\JsonEncoder;
+use Symfony\Component\Serializer\Normalizer\DateTimeNormalizer;
+use Symfony\Component\Serializer\Normalizer\JsonSerializableNormalizer;
+use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
+use Symfony\Component\Serializer\Serializer;
+use Symfony\Component\Serializer\SerializerInterface;
+
 /**
  * @author Christopher Hertel <mail@christopher-hertel.de>
  */
 final readonly class ToolResultConverter
 {
-    /**
-     * @param \JsonSerializable|\Stringable|array<int|string, mixed>|float|string|null $result
-     */
-    public function convert(\JsonSerializable|\Stringable|array|float|string|\DateTimeInterface|null $result): ?string
-    {
-        if (null === $result) {
-            return null;
-        }
+    public function __construct(
+        private SerializerInterface $serializer = new Serializer([new JsonSerializableNormalizer(), new DateTimeNormalizer(), new ObjectNormalizer()], [new JsonEncoder()]),
+    ) {
+    }
 
-        if ($result instanceof \JsonSerializable || \is_array($result)) {
-            return json_encode($result, flags: \JSON_THROW_ON_ERROR);
+    public function convert(mixed $result): ?string
+    {
+        if (null === $result || \is_string($result)) {
+            return $result;
         }
 
-        if (\is_float($result) || $result instanceof \Stringable) {
+        if ($result instanceof \Stringable) {
             return (string) $result;
         }
 
-        if ($result instanceof \DateTimeInterface) {
-            return $result->format(\DATE_ATOM);
-        }
-
-        return $result;
+        return $this->serializer->serialize($result, 'json');
     }
 }

tests/Chain/Toolbox/ToolResultConverterTest.php

@@ -5,6 +5,7 @@
 namespace PhpLlm\LlmChain\Tests\Chain\Toolbox;
 
 use PhpLlm\LlmChain\Chain\Toolbox\ToolResultConverter;
+use PhpLlm\LlmChain\Tests\Fixture\StructuredOutput\UserWithConstructor;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Test;
@@ -34,7 +35,7 @@ public static function provideResults(): \Generator
 
         yield 'string' => ['plain string', 'plain string'];
 
-        yield 'datetime' => [new \DateTimeImmutable('2021-07-31 12:34:56'), '2021-07-31T12:34:56+00:00'];
+        yield 'datetime' => [new \DateTimeImmutable('2021-07-31 12:34:56'), '"2021-07-31T12:34:56+00:00"'];
 
         yield 'stringable' => [
             new class implements \Stringable {
@@ -55,5 +56,16 @@ public function jsonSerialize(): array
             },
             '{"key":"value"}',
         ];
+
+        yield 'object' => [
+            new UserWithConstructor(
+                id: 123,
+                name: 'John Doe',
+                createdAt: new \DateTimeImmutable('2021-07-31 12:34:56'),
+                isActive: true,
+                age: 18,
+            ),
+            '{"id":123,"name":"John Doe","createdAt":"2021-07-31T12:34:56+00:00","isActive":true,"age":18}',
+        ];
     }
 }