Fix #5: Add XML serializer

composer.json

@@ -16,7 +16,9 @@
         "source": "https://github.com/yiisoft/serializer"
     },
     "require": {
-        "php": "^7.4|^8.0"
+        "php": "^7.4|^8.0",
+        "symfony/serializer": "^5.1.8",
+        "symfony/property-access": "^5.1.8"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.4",

src/XmlSerializer.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Yiisoft\Serializer;
+
+use Symfony\Component\Serializer\Encoder\XmlEncoder;
+use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
+use Symfony\Component\Serializer\Serializer;
+
+/**
+ * XmlSerializer serializes data in XML format.
+ */
+final class XmlSerializer implements SerializerInterface
+{
+    private Serializer $serializer;
+
+    /**
+     * @param string $rootTag The name of the root element.
+     * @param string $version The XML version.
+     * @param string $encoding The XML encoding.
+     */
+    public function __construct(string $rootTag = 'response', string $version = '1.0', string $encoding = 'UTF-8')
+    {
+        $this->serializer = new Serializer([new ObjectNormalizer()], [new XmlEncoder([
+            XmlEncoder::ROOT_NODE_NAME => $rootTag,
+            XmlEncoder::VERSION => $version,
+            XmlEncoder::ENCODING => $encoding,
+        ])]);
+    }
+
+    public function serialize($value): string
+    {
+        return $this->serializer->serialize($value, XmlEncoder::FORMAT);
+    }
+
+    public function unserialize(string $value)
+    {
+        return $this->serializer->decode($value, XmlEncoder::FORMAT);
+    }
+}

tests/TestAsset/DummyData.php

@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Yiisoft\Serializer\Tests\TestAsset;
+
+final class DummyData
+{
+    private string $string;
+    private int $int;
+    private float $float;
+    private array $array;
+    private bool $bool;
+
+    public function __construct(string $string, int $int, float $float, array $array, bool $bool)
+    {
+        $this->string = $string;
+        $this->int = $int;
+        $this->float = $float;
+        $this->array = $array;
+        $this->bool = $bool;
+    }
+
+    public function getString(): string
+    {
+        return $this->string;
+    }
+
+    public function getInt(): int
+    {
+        return $this->int;
+    }
+
+    public function getFloat(): float
+    {
+        return $this->float;
+    }
+
+    public function getArray(): array
+    {
+        return $this->array;
+    }
+
+    /**
+     * @param bool $asInt
+     * @return bool|int
+     */
+    public function isBool(bool $asInt = false)
+    {
+        return $asInt ? (int) $this->bool : $this->bool;
+    }
+}

tests/TestAsset/DummyDataHelper.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Yiisoft\Serializer\Tests\TestAsset;
+
+use function preg_replace;
+use function sprintf;
+
+final class DummyDataHelper
+{
+    public static function xml(string $data, string $version = '1.0', string $encoding = 'UTF-8'): string
+    {
+        $startLine = sprintf('<?xml version="%s" encoding="%s"?>', $version, $encoding);
+        return $startLine . "\n" . preg_replace('/(?!item)\s(?!key)/', '', $data) . "\n";
+    }
+}

tests/XmlSerializerTest.php

@@ -0,0 +1,125 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Yiisoft\Serializer\Tests;
+
+use stdClass;
+use Yiisoft\Serializer\SerializerInterface;
+use Yiisoft\Serializer\Tests\TestAsset\DummyData;
+use Yiisoft\Serializer\Tests\TestAsset\DummyDataHelper;
+use Yiisoft\Serializer\XmlSerializer;
+
+final class XmlSerializerTest extends SerializerTest
+{
+    public function getSerializer(): SerializerInterface
+    {
+        return new XmlSerializer();
+    }
+
+    public function serializeProvider(): array
+    {
+        return $this->dataProvider();
+    }
+
+    public function unserializeProvider(): array
+    {
+        return $this->dataProvider();
+    }
+
+    public function dataProvider(): array
+    {
+        $data = [
+            'int' => [1, '<response>1</response>',],
+            'float' => [1.1, '<response>1.1</response>',],
+            'string' => ['a', '<response>a</response>',],
+            'null' => [null, '<response/>',],
+            'array' => [
+                [
+                    'int' => 1,
+                    'float' => 1.1,
+                    'string' => 'a',
+                    'null' => null,
+                    'without-key-1',
+                    'without-key-2',
+                    'nested' => [
+                        'int' => 1,
+                        'float' => 1.1,
+                        'string' => 'a',
+                        'null' => null,
+                        'without-key-1',
+                        'without-key-2',
+                    ]
+                ],
+                <<<EOF
+                    <response>
+                        <int>1</int>
+                        <float>1.1</float>
+                        <string>a</string>
+                        <null/>
+                        <item key="0">without-key-1</item>
+                        <item key="1">without-key-2</item>
+                        <nested>
+                            <int>1</int>
+                            <float>1.1</float>
+                            <string>a</string>
+                            <null/>
+                            <item key="0">without-key-1</item>
+                            <item key="1">without-key-2</item>
+                        </nested>
+                    </response>
+                EOF,
+            ],
+        ];
+
+        foreach ($data as $key => $value) {
+            $value[1] = DummyDataHelper::xml($value[1]);
+            $data[$key] = $value;
+        }
+
+        return $data;
+    }
+
+    public function testConstructorWithPassedArguments(): void
+    {
+        $serializer = new XmlSerializer($rootTag = 'foo', $version = '2.0', $encoding = 'Windows-1252');
+        $this->assertSame(
+            DummyDataHelper::xml("<{$rootTag}/>", $version, $encoding),
+            $serializer->serialize([])
+        );
+    }
+
+    public function testSerializeEmptyObject(): void
+    {
+        $serializer = new XmlSerializer();
+        $this->assertSame(DummyDataHelper::xml('<response/>'), $serializer->serialize(new stdClass()));
+    }
+
+    public function testSerializeAndUnserialize(): void
+    {
+        $serializer = new XmlSerializer();
+        $object = new DummyData('foo', 99, 1.1, [1, 'foo' => 'bar'], false);
+        $xml = <<<EOF
+            <response>
+                <string>{$object->getString()}</string>
+                <int>{$object->getInt()}</int>
+                <float>{$object->getFloat()}</float>
+                <array>
+                    <item key="0">1</item>
+                    <foo>bar</foo>
+                </array>
+                <bool>{$object->isBool(true)}</bool>
+            </response>
+        EOF;
+        $array = [
+            'string' => $object->getString(),
+            'int' => $object->getInt(),
+            'float' => $object->getFloat(),
+            'array' => $object->getArray(),
+            'bool' => (string) $object->isBool(true),
+        ];
+
+        $this->assertSame(DummyDataHelper::xml($xml), $serializer->serialize($object));
+        $this->assertEquals($array, $serializer->unserialize($xml));
+    }
+}