Serializer.php

<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace Symfony\Component\Serializer;

use Symfony\Component\Serializer\Encoder\ChainDecoder;
use Symfony\Component\Serializer\Encoder\ChainEncoder;
use Symfony\Component\Serializer\Encoder\EncoderInterface;
use Symfony\Component\Serializer\Encoder\DecoderInterface;
use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
use Symfony\Component\Serializer\Exception\RuntimeException;
use Symfony\Component\Serializer\Exception\LogicException;
use Symfony\Component\Serializer\Exception\UnexpectedValueException;

/**
 * Serializer serializes and deserializes data
 *
 * objects are turned into arrays by normalizers
 * arrays are turned into various output formats by encoders
 *
 * $serializer->serialize($obj, 'xml')
 * $serializer->decode($data, 'xml')
 * $serializer->denormalize($data, 'Class', 'xml')
 *
 * @author Jordi Boggiano <j.boggiano@seld.be>
 * @author Johannes M. Schmitt <schmittjoh@gmail.com>
 * @author Lukas Kahwe Smith <smith@pooteeweet.org>
 */
class Serializer implements SerializerInterface, NormalizerInterface, DenormalizerInterface, EncoderInterface, DecoderInterface {
  protected $encoder;
  protected $decoder;
  protected $normalizers = array();
  protected $normalizerCache = array();
  protected $denormalizerCache = array();
  public function __construct(array $normalizers = array(), array $encoders = array()) {
    foreach ($normalizers as $normalizer) {
      if ($normalizer instanceof SerializerAwareInterface) {
        $normalizer
          ->setSerializer($this);
      }
    }
    $this->normalizers = $normalizers;
    $decoders = array();
    $realEncoders = array();
    foreach ($encoders as $encoder) {
      if ($encoder instanceof SerializerAwareInterface) {
        $encoder
          ->setSerializer($this);
      }
      if ($encoder instanceof DecoderInterface) {
        $decoders[] = $encoder;
      }
      if ($encoder instanceof EncoderInterface) {
        $realEncoders[] = $encoder;
      }
    }
    $this->encoder = new ChainEncoder($realEncoders);
    $this->decoder = new ChainDecoder($decoders);
  }

  /**
   * {@inheritdoc}
   */
  public final function serialize($data, $format) {
    if (!$this
      ->supportsEncoding($format)) {
      throw new UnexpectedValueException('Serialization for the format ' . $format . ' is not supported');
    }
    if ($this->encoder
      ->needsNormalization($format)) {
      $data = $this
        ->normalize($data, $format);
    }
    return $this
      ->encode($data, $format);
  }

  /**
   * {@inheritdoc}
   */
  public final function deserialize($data, $type, $format) {
    if (!$this
      ->supportsDecoding($format)) {
      throw new UnexpectedValueException('Deserialization for the format ' . $format . ' is not supported');
    }
    $data = $this
      ->decode($data, $format);
    return $this
      ->denormalize($data, $type, $format);
  }

  /**
   * {@inheritdoc}
   */
  public function normalize($data, $format = null) {
    if (null === $data || is_scalar($data)) {
      return $data;
    }
    if (is_object($data) && $this
      ->supportsNormalization($data, $format)) {
      return $this
        ->normalizeObject($data, $format);
    }
    if ($data instanceof \Traversable) {
      $normalized = array();
      foreach ($data as $key => $val) {
        $normalized[$key] = $this
          ->normalize($val, $format);
      }
      return $normalized;
    }
    if (is_object($data)) {
      return $this
        ->normalizeObject($data, $format);
    }
    if (is_array($data)) {
      foreach ($data as $key => $val) {
        $data[$key] = $this
          ->normalize($val, $format);
      }
      return $data;
    }
    throw new UnexpectedValueException('An unexpected value could not be normalized: ' . var_export($data, true));
  }

  /**
   * {@inheritdoc}
   */
  public function denormalize($data, $type, $format = null) {
    return $this
      ->denormalizeObject($data, $type, $format);
  }

  /**
   * {@inheritdoc}
   */
  public function supportsNormalization($data, $format = null) {
    try {
      $this
        ->getNormalizer($data, $format);
    } catch (RuntimeException $e) {
      return false;
    }
    return true;
  }

  /**
   * {@inheritdoc}
   */
  public function supportsDenormalization($data, $type, $format = null) {
    try {
      $this
        ->getDenormalizer($data, $type, $format = null);
    } catch (RuntimeException $e) {
      return false;
    }
    return true;
  }

  /**
   * {@inheritdoc}
   */
  private function getNormalizer($data, $format = null) {
    foreach ($this->normalizers as $normalizer) {
      if ($normalizer instanceof NormalizerInterface && $normalizer
        ->supportsNormalization($data, $format)) {
        return $normalizer;
      }
    }
    throw new RuntimeException(sprintf('No normalizer found for format "%s".', $format));
  }

  /**
   * {@inheritdoc}
   */
  private function getDenormalizer($data, $type, $format = null) {
    foreach ($this->normalizers as $normalizer) {
      if ($normalizer instanceof DenormalizerInterface && $normalizer
        ->supportsDenormalization($data, $type, $format)) {
        return $normalizer;
      }
    }
    throw new RuntimeException(sprintf('No denormalizer found for format "%s".', $format));
  }

  /**
   * {@inheritdoc}
   */
  public final function encode($data, $format) {
    return $this->encoder
      ->encode($data, $format);
  }

  /**
   * {@inheritdoc}
   */
  public final function decode($data, $format) {
    return $this->decoder
      ->decode($data, $format);
  }

  /**
   * Normalizes an object into a set of arrays/scalars
   *
   * @param object $object object to normalize
   * @param string $format format name, present to give the option to normalizers to act differently based on formats
   * @return array|scalar
   */
  private function normalizeObject($object, $format = null) {
    if (!$this->normalizers) {
      throw new LogicException('You must register at least one normalizer to be able to normalize objects.');
    }
    $class = get_class($object);
    if (isset($this->normalizerCache[$class][$format])) {
      return $this->normalizerCache[$class][$format]
        ->normalize($object, $format);
    }
    foreach ($this->normalizers as $normalizer) {
      if ($normalizer
        ->supportsNormalization($object, $format)) {
        $this->normalizerCache[$class][$format] = $normalizer;
        return $normalizer
          ->normalize($object, $format);
      }
    }
    throw new UnexpectedValueException('Could not normalize object of type ' . $class . ', no supporting normalizer found.');
  }

  /**
   * Denormalizes data back into an object of the given class
   *
   * @param mixed  $data   data to restore
   * @param string $class  the expected class to instantiate
   * @param string $format format name, present to give the option to normalizers to act differently based on formats
   * @return object
   */
  private function denormalizeObject($data, $class, $format = null) {
    if (!$this->normalizers) {
      throw new LogicException('You must register at least one normalizer to be able to denormalize objects.');
    }
    if (isset($this->denormalizerCache[$class][$format])) {
      return $this->denormalizerCache[$class][$format]
        ->denormalize($data, $class, $format);
    }
    foreach ($this->normalizers as $normalizer) {
      if ($normalizer
        ->supportsDenormalization($data, $class, $format)) {
        $this->denormalizerCache[$class][$format] = $normalizer;
        return $normalizer
          ->denormalize($data, $class, $format);
      }
    }
    throw new UnexpectedValueException('Could not denormalize object of type ' . $class . ', no supporting normalizer found.');
  }

  /**
   * {@inheritdoc}
   */
  public function supportsEncoding($format) {
    return $this->encoder
      ->supportsEncoding($format);
  }

  /**
   * {@inheritdoc}
   */
  public function supportsDecoding($format) {
    return $this->decoder
      ->supportsDecoding($format);
  }

}