denormalize and normalize statement timestamps

This finishes pull request #9 by adding a normalizer that is able to
deal with ISO 8601 formatted dates.

Author: xabbuh

CHANGELOG.md

@@ -1,10 +1,11 @@
 CHANGELOG
 =========
 
-0.2.x (next version)
+0.2.2
 -----
 
-* Added support for (de)serializing 'created' and 'stored' Statement properties.
+* Added support for (de)serializing a statement's `timestamp` and `stored`
+  properties.
 
 0.2.1
 -----

composer.json

@@ -17,8 +17,8 @@
         "symfony/serializer": "~2.8|~3.0"
     },
     "require-dev": {
-        "php-xapi/json-test-fixtures": "^0.2.0",
-        "php-xapi/test-fixtures": "^0.3.0",
+        "php-xapi/json-test-fixtures": "^0.2.2",
+        "php-xapi/test-fixtures": "^0.4.0",
         "phpspec/phpspec": "~2.0"
     },
     "conflict": {

spec/Normalizer/TimestampNormalizerSpec.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace spec\Xabbuh\XApi\Serializer\Normalizer;
+
+use PhpSpec\ObjectBehavior;
+
+class TimestampNormalizerSpec extends ObjectBehavior
+{
+    function it_is_a_normalizer()
+    {
+        $this->shouldHaveType('Symfony\Component\Serializer\Normalizer\NormalizerInterface');
+    }
+
+    function it_can_normalize_datetime_objects()
+    {
+        $this->supportsNormalization(new \DateTime())->shouldBe(true);
+    }
+
+    function it_cannot_normalize_datetime_like_string()
+    {
+        $this->supportsNormalization('2004-02-12T15:19:21+00:00')->shouldBe(false);
+    }
+
+    function it_normalizes_datetime_objects_as_iso_8601_formatted_strings()
+    {
+        $date = new \DateTime();
+        $date->setTimezone(new \DateTimeZone('UTC'));
+        $date->setDate(2004, 2, 12);
+        $date->setTime(15, 19, 21);
+
+        $this->normalize($date)->shouldReturn('2004-02-12T15:19:21+00:00');
+    }
+
+    function it_throws_an_exception_when_data_other_than_datetime_objects_are_passed()
+    {
+        $this->shouldThrow('Symfony\Component\Serializer\Exception\InvalidArgumentException')->during('normalize', array('2004-02-12T15:19:21+00:00'));
+    }
+
+    function it_is_a_denormalizer()
+    {
+        $this->shouldHaveType('Symfony\Component\Serializer\Normalizer\DenormalizerInterface');
+    }
+
+    function it_can_denormalize_to_datetime_objects()
+    {
+        $this->supportsDenormalization('2004-02-12T15:19:21+00:00', 'DateTime')->shouldBe(true);
+    }
+
+    function it_denormalizes_iso_8601_formatted_strings_to_datetime_objects()
+    {
+        $date = $this->denormalize('2004-02-12T15:19:21+00:00', 'DateTime');
+
+        $date->getTimezone()->shouldBeLike(new \DateTimeZone('UTC'));
+        $date->format('Y-m-d H:i:s')->shouldReturn('2004-02-12 15:19:21');
+    }
+}

src/Normalizer/TimestampNormalizer.php

@@ -0,0 +1,60 @@
+<?php
+
+/*
+ * This file is part of the xAPI package.
+ *
+ * (c) Christian Flothmann <christian.flothmann@xabbuh.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Xabbuh\XApi\Serializer\Normalizer;
+
+use Symfony\Component\Serializer\Exception\InvalidArgumentException;
+use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
+use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
+
+/**
+ * Normalizes and denormalizes xAPI statement timestamps.
+ *
+ * @author Christian Flothmann <christian.flothmann@xabbuh.de>
+ */
+final class TimestampNormalizer implements DenormalizerInterface, NormalizerInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function denormalize($data, $class, $format = null, array $context = array())
+    {
+        return new \DateTime($data);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function supportsDenormalization($data, $type, $format = null)
+    {
+        return 'DateTime' === $type;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function normalize($object, $format = null, array $context = array())
+    {
+        if (!($object instanceof \DateTime || $object instanceof \DateTimeInterface)) {
+            throw new InvalidArgumentException(sprintf('Expected \DateTime object or object implementing \DateTimeInterface (got "%s").', is_object($object) ? get_class($object) : gettype($object)));
+        }
+
+        return $object->format('c');
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function supportsNormalization($data, $format = null)
+    {
+        return $data instanceof \DateTime || $data instanceof \DateTimeInterface;
+    }
+}

src/Serializer.php

@@ -13,7 +13,6 @@
 
 use Symfony\Component\Serializer\Encoder\JsonEncoder;
 use Symfony\Component\Serializer\Normalizer\ArrayDenormalizer;
-use Symfony\Component\Serializer\Normalizer\DateTimeNormalizer;
 use Symfony\Component\Serializer\Normalizer\PropertyNormalizer;
 use Symfony\Component\Serializer\SerializerInterface;
 use Symfony\Component\Serializer\Serializer as SymfonySerializer;
@@ -24,6 +23,7 @@
 use Xabbuh\XApi\Serializer\Normalizer\ResultNormalizer;
 use Xabbuh\XApi\Serializer\Normalizer\StatementNormalizer;
 use Xabbuh\XApi\Serializer\Normalizer\StatementResultNormalizer;
+use Xabbuh\XApi\Serializer\Normalizer\TimestampNormalizer;
 
 /**
  * Entry point to set up the {@link \Symfony\Component\Serializer\Serializer Symfony Serializer component}
@@ -47,10 +47,10 @@ public static function createSerializer()
             new ResultNormalizer(),
             new StatementNormalizer(),
             new StatementResultNormalizer(),
+            new TimestampNormalizer(),
             new ArrayDenormalizer(),
             new FilterNullValueNormalizer(new PropertyNormalizer()),
             new PropertyNormalizer(),
-            new DateTimeNormalizer()
         );
         $encoders = array(
             new JsonEncoder(),

tests/StatementSerializerTest.php

@@ -65,6 +65,10 @@ public function statementProvider()
                 StatementJsonFixtures::getMinimalStatement(),
                 StatementFixtures::getMinimalStatement(),
             ),
+            'typical-statement' => array(
+                StatementJsonFixtures::getTypicalStatement(),
+                StatementFixtures::getTypicalStatement(),
+            ),
             'statement-reference' => array(
                 StatementJsonFixtures::getStatementWithStatementRef(),
                 StatementFixtures::getStatementWithStatementRef(),